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					Wednesday, August 31st, 2005 : Collegium Stomatologicum of Poznan University of
Medical Sciences

Time Main Hall Room A Room B Room C
10.00
Implantoprosthetics Workshop (Professors: G. Zarb, Z. Bereznowski, Z. Sokalski)
14.00
14.30
Trustee Meeting
15.15
15.30
Council Meeting
16.30
National Committee Meeting
19.00
Speakers' Dinner (only by personal invitation)

Thursday, September 1st, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
10.00
Opening of the Conference
10.15
Poster set-up

Session G1
Oxford lecture
K01: Implications for Contemporary Prosthodontics Rehabilitation
Eugeniusz Spiechowicz
11.00
K02: The Impact of Osseointegration on the Management of partial Edentulism
George Zarb
11.45
Discussion
12.00
Coffee break
12.30

Session G2
K03: The development, structure, and remodeling of the maxilla and the mandible
Witold Wozniak

Session 1
O01: The reconstruction of edentulous maxilla and mandible with fixed prosthesis supported by
immediatelly implants
Zdzislaw Bereznowski*, Maciej Dijakiewicz, Violetta Szycik

Session 2
O07: A joint clinicostatistical study on the prevalence of Denture Stomatitis
Alcibiades Zissis, Stavros Yannikakis*, Alan Harisson
12.45
O02: Systematic reviews of survival of tooth and implant-supported FPDs
Bjarni E. Pjetursson*, Ken Tan, Niklaus P. Lang, Urs Bragger, Matthias Egger, Marcel Zwahlen
O08: Denture stomatitis in type II diabetes mellitus - clinical and microbiological study
Barbara Dorocka-Bobkowska*, Ejvind Budtz-Jorgensen, Bogna Wierusz-Wysocka, Wieslaw
Hedzelek
13.00
O03: Longterm observation of mandibular overdenture supported by implants
Rolf Rosch*, Pawel Pazera, Regina Mericske-Stern
O09: Helicobacter pylori infection and stomatitis prothetica hyperplastica
Bartlomiej W. Loster*, Wladyslaw Bielanski, Stanislaw Majewski, Stanislaw J. Konturek, Witold
Ziemniak
13.15
K04: Current Status of Overdenture and Complete Denture Construction
Toshio Hosoi
O04: Immediate occlusal loading in mandibular fully edentulous patients
Piotr Majewski*, Krzysztof Gronkiewicz
O10: The comparison of the condition of mandible between postmenopausal women with
different mineral status of organism
Maria Golebiewska*, Ewa Kulikowska-Bielaczyc

Thursday, September 1st, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
13.30
O05: Overdentures supported on implants – evaluation of a treatment results
Piotr Okonski*, Elzbieta Mierzwinska-Nastalska, Jerzy Gladkowski, Ewa Adamczyk-Sosinska,
Eugeniusz Spiechowicz
O11: The influence of masticatory deficiency on gastric emptying in patients with dyspepsia
Teresa Sierpinska*, Jan Dlugosz, Maria Golebiewska, Adam Chwiesko
13.45
O06: Influence of angled abutments on stress distribution in various bone types
Volkan Asar*, Hande Ataman, Yavuz Burgaz, Celil Dincer
O12: The influence of the active viral infection, chronic inflammation on the mucosal overgrowth
Dorota Szubinska, Andrzej Wojtowicz*, Piotr Fiedor
14.00
Discussion
14.15
Lunch break Poster Session
14.45
15.45

Session G3
K05: Canine guided full dentures - clinical procedure and long term results
Ingrid Grunert

Session 3
O13: Remote symptoms in patients with compound temporomandibular joint disc displacement
Maria Kleinrok*, Przemyslaw Kleinrok, Beata Piorkowska-Skrabucha, Janusz Kleinrok,
Malgorzata Kostrzewa, Marzena Janczarek

Session 4
O19: Pressure variations under complete upper dentures with a palatal relief lined with silicone
elastomer
Pawel Piotrowski*, Zdzislaw Krysinski
16.00
O14: The initial management of the temporomandibular disorders
Jolanta Kostrzewa-Janicka*, Elzbieta Mierzwinska-Nastalska, Artur Anulewicz, Marek Pratnicki,
Hubert Wanyura, Zygmunt Stopa
O20: Multidisciplinary therapy of cleft patients
Marie Bartonova*, Tatjana Dostalova, Hana Hubalkova
16.15
O15: Prevalence of oromandibular dysfunction (OMD) in adolescents in Lodz
Lukasz Pawlak, Monika Sajewicz-Rosiak*, Anita Wierzbicka-Ferszt, Katarzyna Romanczuk-Split,
Wojciech Split
O21: Estimation of adsorption of calcium phosphate to modified titanium surfaces
Barbara Sikorska*, Wieslaw Hedzelek, Ludwik Domka, Leszek Kubisz

Thursday, September 1st, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
16.30
K06: Assessment of selected border contours of the working impressions of edentulous jaws:
criterion of reproducibility
Zdzislaw Krysinski
O16: Psychical characteristics of functional-morphological disorders of the stomatognatic system
Eliza Sobczyk*, Halina Tejchman, Zofia Majdanska, Irena Leszczynska
O22: The influence of sulphur reducing bacteria on the dental alloys surface
Justyna Otulakowska-Skrzynska*, Anna Kedzia, John W. Nicholson
16.45
O17: The Treatment of pathological disorders in the facial nerve with electrostimulation and
kinesiotherapy - two case studies
Anna Sojka*, Juliusz Huber, Agnieszka Wiertel-Krawczuk, Wieslaw Hedzelek, Alicja Witkowska
O23: Infrared spectrophotometric identification of dental material released during mastication
Agnieszka Marcinkowska*, Roman Wachowiak, Wieslaw Hedzelek
17.00
O18: Prevalance of muscle disorders in multiple sclerosis patients
Zoran Kovac*, Ivone Uhac, Daniela Kovacevic, Natasa Blecic, Renata Grzic, Miranda Muhvic-
Urek
O24: Acute phase reaction after complex treatment in refractory periodontitis
Anna Kurhanska-Flisykowska*, Magdalena Sobieska, Agnieszka Wasiewicz
17.15
Discussion
17.30
19.00
Sightseeing of Collegium Stomatologicum
20.00
Collegium Stomatologicum of Poznan University of Medical Sciences
Opening Ceremony - Cocktail Reception
The "MoCarta" Group Concert

Friday, September 2nd, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
09.30

Session G4
K07: Dental Implantology - materials, designs and education. The Toronto Inheritance
John Hobkirk
09.45
10.00
10.15
K08: Is it not necessary to know where the occlusal position is?
Shunji Fukushima*, Yuko Shigeta, Takumi Ogawa
10.30
10.45
11.00
Discussion
11.15
Coffee break Poster Session
11.45

Session G5
K09: Modern removable partial denture indication, construction and design
Bengt Owall

Session 5
O25: Facial prosthesis with dental implants support
Jiri Holakovsky*, Tatjana Dostalova, Jiri Mazanek, Hana Hubalkova, Zdenek Nathansky

Session 6
O31: Multi-center research for shortened dental arch treatment in Japan
Yoshimasa Igarashi*, Yusuke Maruyama, Shuichiro Yamashita, Hideyuki Koike, Yuki Matsuyama
12.00
O26: The prosthetic rehabilitation following malignant tumor surgery in maxillofacial region
Krystyna Rusiniak-Kubik*, Dariusz Rolski, Elzbieta Mierzwinska-Nastalska
O32: Shape and size of dental arch - healthy, orthodontic and cleft patients
Tatjana Dostalova*, Radek Hippmann, Marie Bartonova, Vladimir Smutny, Miroslav Peterka
12.15
O27: Options of prosthetic treatment – classical methods versus implants - case reports
Jindrich Charvat*, Hana Hubalkova, Tatjana Dostalova, Marie Bartonova
O33: Relative analgesia and the prosthetic management of the "gagging" patient
Mark Packer*, Barry Lall, Camilla Joarder
12.30
K10: Indication classes of modern dental implantology
Manfred Lang
O28: The influence of variable, low frequency magnetic fields on the bone tissue structure after
dental implantation procedure
Paulina Klapcinska*, Rajmund Orlicki, Olga Tos
O34: Prevalence of Combination Syndrome among geriatric denture patients
Honorata Krawczykowska*, Halina Panek, Ewa Kalecinska

Friday, September 2nd, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
12.45
O29: Titanium in Magnetic Resonance Imaging of Head and Neck Area
Hana Hubalkova*, Zenon Starcuk, Igor Linetskiy, Jiri Mazanek, Tatjana Dostalova
O35: Effect of crown material and cement type on heat transfer
Nesrin Anil, Canan Hekimoglu, Umut Cakan*
13.00
O30: Possibilities of restoring teeth in epileptic patients with mixed dental losses
Slawomir Pasiek*, Maciej Szwankowski
O36: Modeling and contact simulation of prosthetic restoration with tissues of stomatognathic
system
Anna Ryniewicz*, Wojciech Ryniewicz
13.15
Discussion
13.30
Lunch break Poster Session
14.00
14.30
EPA Business Assembly Meeting
15.30
Session G6
K11: Prosthodontic considerations in geriatric dentistry
Jaime Pietrokovski

Session 7
O37: Preparation for testing psychometric properties of Hungarian version of OHIP
Gyula Szabo

Session 8
O43: Evaluation of the utility of anthropometric parameters in predicting the width of maxillary
anterior teeth
Gloria Staka*, Agron Rexhepi, Dugagjin Sokoli
15.45
O38: The evaluation of the muscles' relaxation influenced of the occlusal splint
Malgorzata Pihut*, Grazyna Wisniewska
O44: Morphometric analysis of mandible head morphometry
Jurand Mackiewicz*, Maria Prosba-Mackiewicz
16.00
O39: The assessment of mandibular movements in edentulous patients after exercises of
efficiency
Maciej Romanowicz*, Maciej Split
O45: Metallic and acrylic dentures base plate and phonetics
Florije Asllani-Hoxha*, Agim Islami, Enis Ahmedi, Kujtim Shala
16.15
K12: The quality of rehabilitation of patients following maxillectomy Peter Likeman
O40: Assessment of mandibular movements in edentulous patients
Maciej Split*, Agnieszka Homa, Wojciech Split
O46: Inlay-onlay bridges in the prosthetic treatment of single missing teeth
Tomasz Kondracki*, Maria Golebiewska

Friday, September 2nd, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
16.30
O41: Assessment of mandibular movements in edentulous patients undertaking prosthetic
treatment
Agnieszka Homa*, Maciej Split, Wojciech Split
O47: Evaluation of the effect of local anaesthesia on blood flow in the dental pulp of vital teeth
Slawomir Pasiek
16.45
O42: Cooperation between prosthetic and psychologist in curing "difficult patients"
Halina Tejchman, Zofia Majdanska, Eliza Sobczyk, Irena Leszczynska*
O48: Chewing forces and methods of measurement in stomatognathic system
Bartlomiej Pawlus*, Rajmund Orlicki, Janusz Juraszek
17.00
Discussion
17.15
20.00
Banquet - Live Music
The Recital of Jacek Wojcicki & The "Akt" Band Concert

Saturday, September 3rd, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
09.30
Session G7
K13: Integrating evidence-based medicine in prosthodontic practice
Asbjorn Jokstad

Session 9
O49: The comparative analysis of the fit of gold, chromium alloy and precision laser welding cast
titanium frameworks
Dagmar Kudrnova*, Marie Bartonova, T. Chlubna Tatjana Dostalova

Session 10
O55: Evaluation of the mechanical properties of different all-ceramic systems
Handan Yilmaz, Cemal Aydin, Esma Basak Gul*
09.45
O50: Effect of Post-Core Materials on Final Color of In-Ceram, IPS Empress
Gulay Uzun, Gurel Pekkan*, Sema Altunsoy, Filiz Keyf
O56: Effect of Pontic Type and Occlusal Form on the Fracture Strength of Fiber-reinforced Inlay-
retained FPDs
Mutlu Ozcan*, Marijn Breuklander
10.00
O51: A long term study on residual monomer release from denture materials
Alcibiades Zissis*, Stavros Yannikakis, Gregory Polyzois, Alan Harisson
O57: Modification of the surface of aramid fibres as reinforcement acrylic resins
Przemyslaw Gajdus*, Wieslaw Hedzelek, Ludwik Domka, Adrianna Malicka
10.15
K14: Cemented versus screw-retained implant restorations: Which is better?
Matthias Kern
O52: The influence of CO2 laser beam on chosen dental materials
Piotr Andrysiak*, Zdzislaw Blaszczak, Wieslaw Hedzelek
O58: Coupled fields analysis /CFA/ of the Cr-Ni alloy-ceramics system
Janusz Juraszek*, Rajmund Orlicki, Grzegorz Wycisk
10.30
O53: An investigation of the accuracy (inaccuracy) of refixing broken teeth to stone casts
Peter Likeman*, George Paolinelis
O59: Structure of ceramics bonds
Maria Richert*, Rajmund Orlicki, Beata Leszczynska
10.45
O54: Staining techniques - comparative histological studies on human and bovine enamel
Bogdan Miskowiak, Teresa Matthews-Brzozowska, Katarzyna Mehr*
O60: Sol - gel bioceramic materials for dentistry
Michal Posturzynski*, Rajmund Orlicki, Jozef Gluszek, Bartlomiej Pawlus
11.00
Discussion
11.15
Coffee break Poster Session
11.45

Session G8
K15: Specialty in Prosthetic Dentistry in Europe. Status and need for harmonisation
Bengt Owall

Session 11
O61: Long-term retentive forces of double crowns with additional attachment
Hans-Jurgen Wenz*, Frank Emde, Djamila Appelt

Session 12
O66: Tooth and soft tissue preparation for achieving esthetic results in fixed prosthodontics
Daniel Ziskind

Poster tear-down

Saturday, September 3rd, 2005 : Conference Centre of Poznan University of Technology

Time Main Hall Room A Room B Room C
12.00
O62: The wear of precision attachments under occlusal load - in vitro study
Szymon Rzatowski*, Wieslaw Hedzelek, Boguslaw Mroz, Piotr Biskupski
O67: Aesthetic correction of anterior teeth in periodontally compromised dentition
Dagmar Vahalova
12.15
K16: The impression in fixed prosthodontics: from the tradition to the new horizons
Enrico Gherlone*, Francesco Sanfilippo
O63: Mathematical modeling of stress distribution in a lower jaw with a partial removable denture
Sonia Bartakova*, Z Florian, J Suchanek, Jiri Vanek
O68: Examination of the colour durability of selected prosthetic materials
Kamila Linkowska-Swidzinska*, Ryszard Koczorowski, Teodor Swidzinski
12.30
O64: Tribological studies of dental materials used in prosthetic reconstructions
Anna Ryniewicz, Andrzej Gala*, Wojciech Ryniewicz Tomasz Madej
O69: Processing of surface layer of cromium-cobalt alloy and its application in dental
implantology
Sonia Bartakova*, P Prachar, V Brezina, Jiri Vanek
12.45
O65: Electropolishing of cobalt-based dental alloys
Malgorzata Ponto
O70: Multidisciplinary treatment of a woman with Papillon-Lefevre Syndrome - case study
Aneta Wieczorek*, Witold Jurczynski, Laura Czyzewska-Anyszek
13.00
Discussion
13.15
Closing Ceremony
13.30
14.00
Polish Prosthetics Association Annual Meeting
16.00

Collegium Stomatologicum of Poznan University of Medical Sciences
Workshops - 16.00-19.00


K01
KEYNOTE LECTURE
Implications for Contemporary Prosthodontics Rehabilitation
Eugeniusz Spiechowicz
Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
The contemporary prosthodontics rehabilitation is characterized by an enormous progress made
in materials, treatment and restorative methods but at the same time it faces new challenges and
hazards. Following personal professional experience of over 50 years issues concerning
prosthodontics will be discussed and some questions will be put forward. Why complete denture
treatment is sometimes called "the forgotten specialty"? Should all new methods of
implantological oral rehabilitation exclude earlier ones? Why the dental education of patients and
the use of simplest methods are so important in the prevention of denture stomatitis? Can
persistent roots be used instead of implants as a longitudinal retention for overdenture? Is the
chrome-cobalt RPD an absolute therapy in 21st century? Is it really true that patients with allergy
to nickel cannot wear crowns and bridges made of alloys containing this metal? The lecture
presents the author's views on these and other issues on contemporary prosthodontics
rehabilitation.

K02
KEYNOTE LECTURE
The Impact of Osseointegration on the Management of partial Edentulism
George Zarb
Department of Prosthetic Dentistry, University of Toronto, Canada
Brannemark's original research in Implant Prosthodontic management of Edentulism expanded
the envelope of routine edentulous patient care. The extrapolation of that information to the
partially edentulous predicament has now expanded the modern paradigm of dental patient care
even further. The challenge for Prosthodontic Educators now appears to be a reconciliation of
traditional interventions and their inherent ecological risks, with the promise of a less intrusive
management strategy.

K03
KEYNOTE LECTURE
The development, structure, and remodeling of the maxilla and the mandible
Witold Wozniak
Department of Anatomy, Poznan University of Medical Sciences, Poland
The bones of the face develop by intramembranous ossification around the nasal and otic
capsules. The maxilla and mandible develop from the first pharyngeal arch in which the maxillary
and mandibular swellings, and then processes are formed. This takes place during the fourth
embryonic week. The neural crest's cells contribute to the formation of facial bones. The human
maxilla is homologous to the maxilla proper and the premaxilla. This is indicated by the incisive
fissure. The mandible is formed on the lateral side of Meckel`s cartilage and it presents five units,
viz., basal, alveolar, coronoid, condyloid, and angular regions. During the growth of the maxilla
and the mandible, bone is deposited on the surfaces of the cortical plate and the reconstruction is
correlated to the functional and nutritional demands of the bone. These alterations in the structure
are of great importance for remodeling of the bones during ontogenesis, and in adaptation to
function.

K04
KEYNOTE LECTURE
Current Status of Overdenture and Complete Denture Construction
Toshio Hosoi
Tsurumi University, Yokohama, Japan
The elderly population over the age of 65 account for approximately 20% of the total population in
Japan. In contrast to the long life expectancy, the life of teeth is short. In this paper, the author
described the current situation in Japan regarding functional recovery and improvement of QOL in
patients who have lost almost or all of their teeth from the aspect of overdenture and complete
denture. 1. Overdenture 1) Retainer: Magnetic attachments were used as retainers to reduce the
lateral force on an abutment. 2) Reinforcement of the denture base: The overdenture base was
reinforced with metal to prevent cracking due to the stress concentration around the abutment
teeth. The author introduced the metal structure denture used in the laboratory. 3) Implant-
supported overdenture: Implants were placed in the jaw of edentulous patients to support the
overdenture. 2. Complete Denture- Mandibular residual ridge resorption was frequently observed
in old edentulous patients. Therefore, the author presented views on complete dentures in this
paper. 1) The application of soft lining material: Patients often experienced pain and decubitus
ulceration in the mandibular residual ridge due to a low threshold of pain in the residual ridge.
Silicone and acrylic soft lining materials were used for those cases to alleviate pain. 2) The
application of the flange technique: The flange technique was applied on the polished surface of
the denture base to retain the denture by balancing the forces exerted by muscles surrounding
the denture. 3) Lingualized occlusion: The occlusal contacts of artificial teeth follow the guidelines
of lingualized occlusion to prevent movement and rotation of the denture base. 3. Evaluation of
treatment and outcome- The treatment effect was evaluated by functional assessment based on
the dynamic occlusal force calculated from an electromyogram, and patients' assessment by
Visual Analogue Scale (VAS).

K05
KEYNOTE LECTURE
Canine guided full dentures - clinical procedure and long term results
Ingrid Grunert
Department of Preventive and Restorative Dentistry, School of Medicine, University of Innsbruck, Austria
Although the number of full denture treatments is decreasing, it will still be required in future,
because people are getting older and an implant isn't always a practical solution. There are many
different concepts in the treatment of the edentulous patient and various questions are still
unanswered. The way edentulous patients are treated is usually based on the education trends at
dental school. So many dogmas in full denture treatment, e.g. balanced occlusion, are
uncritically overtaken for generations. Starting in 1976 the occlusal concept of full dentures was
changed to a canine guided occlusion at the University of Innsbruck. It seems that through
reducing the elevator muscle activity, following the canine guidance, the alveolar ridges are
preserved, leading over the years to a stable vertical dimension of the dentures. The benefits in
the canine guided set up of the dentures, as well as long term results will be presented.

K06
KEYNOTE LECTURE
Assessment of selected border contours of the working impressions of edentulous jaws:
criterion of
reproducibility
Zdzislaw Krysinski
Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
Before the patient develops an effective muscular control of his new complete denture, it is the
task of the physical factors of retention to withstand the dislodging forces arising in function. The
readiness for action of the physical retentive forces immediately after the first fitting of the finished
dentures in the patient's mouth is their essential advantage. Generally, the atmospheric pressure
is regarded as the most effective physical retentive force. It, however, requires a pressure
differential between the oral cavity and the space between the denture and the underlying
tissues. To attain the required negative pressure beneath the denture when it is displaced in
function, a border seal which prevents saliva and air ingress under the denture is necessary. To
ensure the saliva and/or air-tight border seal of denture, an adequate working impression is a
prerequisite. The border of the impression has to be moulded by the anatomic structures
neighboring the periphery of the subsequent denture during their average most common
functional displacements. For this purpose, the prosthodontist may employ a number of
impression techniques as well as impression materials. Their usefulness is mainly estimated by
the dentist basing on his clinical subjective experience. The speaker tried to objectively assess
the methods and materials used in the impression border moulding by applying the criterion of
repeatability. Impression of edentulous maxilla or mandible were always performed several times
I) using either the open mouth or closed mouth technique, II) making use of the chair side
application of the simulated functional movements of the tissues neighboring the border of the
custom tray or leaving the border of a ready denture to be corrected in the mouth during the
round-the-clock routine physiological oral functions, III) using several impression materials with
different workability characteristics in terms of medium or prolonged plasticity. Greater
reproducibility has been interpreted as a feature of a given method or impression material which
makes it possible to ensure border moulding in conditions closer to physiological ones, thus
enabling the attainment of an effective border seal.

K07
KEYNOTE LECTURE
Dental Implantology - materials, designs and education. The Toronto Inheritance
John Hobkirk
University College London, University of London, United Kingdom
The evolution of dental implantology from alchemy to mainstream therapy is a European
achievement, associated with major scientific advances and the world's largest implant market. It
is an achievement shared globally, and particularly with the New World. This paper explores the
issues of dental implant materials, designs and education as articulated via the 'Toronto Summit'
of 2002, and the work which it stimulated. This addressed a series of key questions and set out
our areas of knowledge and more significantly, of ignorance. With over 200 implant systems on
the market and anatomical and practical considerations imposing significant design constraints,
manufacturers have expended considerable effort in product differentiation. This has occurred
particularly in the areas of material and design, and the results are often marketed in advance of
long-term clinical trials. The many systems which have disappeared from the market, if not our
patients' mouths, bear testament to the process. The Toronto Summit explored the role of
titanium for fabricating dental implants, and highlighted our ignorance of such factors as the
significance of deviation from the ideal Ti surface, organic and inorganic surface modification and
their cost effectiveness. Consideration was also given to implant surfaces and the issues of
macro and micro finishes, and lack of data on their clinical validity, and their interrelationships
with chemical modification. Key recommendations for implant education were the need to include
the subject in undergraduate and postgraduate curricula, to place implant therapy in context as a
treatment modality, not a treatment objective, and to emphasize the science base of the subject.
At a time when new is a synonym for better, and technology offers apparently limitless horizons,
dentistry is struggling to come to terms with the success of implantology. It is a challenge equal to
that of initially establishing its credibility.

K08
KEYNOTE LECTURE
Is it not necessary to know where the occlusal position is?
Shunji Fukushima*, Yuko Shigeta, Takumi Ogawa
Tsurumi University, Yokohama, Japan
Temporomandibular joints (TMJ) are not so stable as previously supposed. Both condyle and
glenoid fossa change their configuration, resulting in various deformities such as osteophyte,
flattening, erosion and so on. Furthermore, articular disc displace from the original position
between condyle and fossa, very often changing the figure. These occurrences can affect the
mandibular position, namely the occlusal contacts between upper and lower dentitions. In this
presentation, I want to discuss the meaning of the above-mentioned occurrence in relation to the
occlusal position. I'll show new images concerning the condyle-fossa relationship during mouth
opening and lateral excursion with four-dimensional analysis of mandibular movements. This
method of analysis was recently developed and can depict movements of any points of the
mandible with anatomical structure. The method combines reconstructed three-dimensional
images from computed tomography with mandibular movement data. Probably there are many
people with unstable condition of TMJ, even though most of them are asymptomatic. However,
we should know how unstable their condylar positions are, as otherwise, we cannot respond
appropriately to patients when they need some dental treatments that possibly change the
condylar position in the fossa. Therefore, it is necessary to diagnose TMJ condition
morphologically and then to evaluate the occlusal position functionally. I want to emphasize the
diagnostic importance of habitual opening and closing movements. I will propose evaluation
criteria and classification of the movements. My presentation will cover the significance of the
occlusal position not theoretically but with clinical cases.

K09
KEYNOTE LECTURE
Modern removable partial denture indication, construction and design
Bengt Owall
University of Copenhagen, Denmark
Even though many textbooks about RPDs still turn up, most of them are based on the well
established but on weak evidence founded principles for handling the mechanical aspects of RPD
design. A slow increase in aspects at risk for tissue damage and side effects can be noted.
Indications in a deeper sense are almost completely missing. The term .partial denture equation'
has been established meaning a balance between the good and the bad that can arise from
RPDs. Basically the indication for RPD treatment is the need for tooth replacement, often also
based on weak evidence, and the choice between the different methods available. With the
increasing use of implants the traditional indication for RPDs, lack of strategically placed
abutment teeth is vanishing. The patients´ subjective preference of fixed contra removable
replacement and economy seems to be the most important basic considerations for the choice of
RPD. So far only vague methods have been developed to evaluate the patient preferences. From
a professional viewpoint there are few, if any, direct indications for RPD treatment. The weighting
that has to be made deals with practical. aspects of burden of the alternative treatments on the
patient, general health and age aspects that may restrict a free choice, available resources and
treatment culture. From a professional viewpoint, side effects as well as technical and biological
prognosis may be the few important domains where evidence is available.

K10
KEYNOTE LECTURE
Indication classes of modern dental implantology
Manfred Lang
Department of Implant Dentistry, New York University, United States
The future of dental implantology lies in applying the maxim of: Putting the least strain on the
patient while achieving the best possible results. "Least strain" means minimising the trauma of
the operation, the length of treatment and the number of sessions treatment takes. At the same
time, this cuts the cost of treatment for the patient. "Best possible results" refers to full restoration
of the masticatory function, optimal aesthetics and long-term success, that is, the implant
reconstruction should function for the rest of the patient's life, if at all possible. In addition to
sound, professional training in implant surgery, it is vital to use the most suitable instruments,
materials (bone substitute materials and membrane technology) and, of course, the ideal implant
system in order to achieve this goal. I will go into all these points in detail in my lecture on classes
of indication in modern dental implantology - from the single tooth implant to the treatment of fully
edentulous patients using fixed or removable reconstructions, both with and without sinus lift. I
will conclude my lecture by presenting the implantation simulator - the "missing link in implant
surgical training", as it were. This dummy gives the dentist hands-on practice in performing the
surgical steps under "real" conditions; from making the incision, preparing the implant bed,
placing the implants, the suturing technique to the sinus lift. At the end of training the dentist
should be able to perform freehand maxillary and mandibular implantation without the need for
navigation or a drilling template.

K11
KEYNOTE LECTURE
Prosthodontic considerations in geriatric dentistry
Jaime Pietrokovski
School of Dental Medicine, Hadassah-Hebrew University of Jerusalem, Israel
There is an urgent need for dental services for the elderly population all over the world. The most
common oral diseases affecting elderly patients are root caries, tooth loss, chronic resorption of
the residual ridges and denture stomatitis. These maladies are related to each other and shall be
dealt by the dental team at the preventive, curative and maintenance treatment levels. Surveys of
1240 residents in seven elderly homes in four countries showed that: a. Medical as well as
administrative authorities did not regard the dental needs of the geriatric population among their
highest priorities. b. In 38% of the examinees soft tissue lesions were detected. c. Precancerous
or cancerous lesions were found in 2.7% of the examinees. d. Tooth decay and gingival
inflammation were present in 74% of the patients. e. Fifty-four % of the examined patients were
fully edentulous. f. One third of the removable dentures were of poor quality. g. More than half of
the patients did not clean properly their prosthesis. h. The majority of the old age home surveyed
did not posses intramural dental services. The reasons were high maintenance costs and low
priority given to orodental problems.

K12
KEYNOTE LECTURE
The quality of rehabilitation of patients following maxillectomy
Peter Likeman
GKT Dental Institute, King's College London, University of London, United Kingdom
The face is the part of our body which we most commonly present to the world. Through it we eat
and breathe and see, and we communicate by speech and facial expression and eye contact. Of
the organs of the face the mouth is the one from which we derive comfort. The infant suckles and
explores new objects with its mouth; the organ of taste is in the mouth and there is comfort in
eating especially in company; it is the organ of speech and we use our mouth to kiss. All dentistry
is potentially an invasion of this sacred space but the assault of major surgery, frequently for the
treatment of life threatening disease is an assault on the essence of ourselves. Rehabilitation of
the patient following maxillectomy is not limited to making an appliance to obturate the opening
between the mouth and nasal cavities but is in many ways a rehabilitation of the whole patient. In
Britain there are organizations to help patients whose faces have been altered by surgery or
accidents to come to terms and live with their acquired features without prejudice. Many patients
are affected psychologically however the prosthodontist, by virtue of the many hours he/she will
spend with the patient, often for the remainder of the patient's life, is in a superb position to use
his counseling skills. The core of this paper is a follow up of maxillectomy patients I have treated,
still living, and I have been able to contact in a setting outside the dental surgery. By removing the
dentist/ patient relationship altogether I was able to discover much more of how their surgery had
affected them and this I would like to share with you.

K13
KEYNOTE LECTURE
Integrating evidence-based medicine in prosthodontic practice
Asbjorn Jokstad
Department of Dental Prosthetics and Oral Function, University of Oslo, Norway
Prosthodontists and the discipline of prosthetic dentistry have been characterized as perplexed in
part by the ruthless demands of accuracy in technical performances and obsessed with
micromeasurements and the severe standards of a handicraft approach to problem solving.
(George Zarb,1994). We need to shift our image of seemingly thriving with the role of being
recognized as the dental technicians of the oral cavity. We should rather aim to become
acknowledged by our peers as the expert diagnostician of our patients' stomatognathic problems,
as well as an insightful colleague and compassionate therapist when considering complex
rehabilitation. This has to be reflected both in our scientific literature and by a patient
management reflecting an evidence-based practice. The lecture aims to describe basic principles
of evidence-based medicine applied to dentistry. The author will also highlight the state of the
scientific evidence in prosthodontics, the prerequisite for a valid informed consent.

K14
KEYNOTE LECTURE
Cemented versus screw-retained implant restorations: Which is better?
Matthias Kern
Christian-Albrechts University at Kiel, Germany
Over the years fixed partial dentures (FPDs) on implants have been retained by occlusal screws
with the advantage of predictable and easy retrievability. However, screw retention has significant
disadvantages, e.g. occlusal screw access holes compromise esthetics and function and often a
passive fit is difficult to achieve. Lateral set screws in the restorations improve esthetics and
occlusal function but the lingual access openings might irritate sensible patients. In addition,
enlarged gaps and hollow spaces between the restoration and the mesostructure might lead to
malodor and irritation of taste. Because of the excellent reliability of today's implant therapy and
the improved mechanic stability of the implant-abutment connection of many implant systems, the
cementation of implant restorations seems to be more and more reasonable. The cementation of
implant restorations eliminates unaesthetic screw access holes. In addition, cemented
restorations have the potential to compensate for any minor dimensional discrepancies in the fit
of restorations to abutments, which can contribute to lack of passivity. Minor dimensional
discrepancies may be compensated for by using cement and cement space. Finally, the
elimination of screws and mesostructures reduces the overall costs of implant therapy.
Depending on the kind and dimension of the implant restoration temporary or definitive cements
can be used, both offering unique advantages. Advantages and disadvantages of the different
options for the fixation of implant restorations are discussed and guidelines for the decision are
presented.

K15
KEYNOTE LECTURE
Specialty in Prosthetic Dentistry in Europe. Status and need for harmonisation
Bengt Owall
University of Copenhagen, Denmark
About 50 countries in the world, and 19 in Europe, in January 2005, had a formally recognized
specialty. There seems to be a unanimous background for the establishment of a specialty;
address a clear health need; that it is best developed through a collaboration between regulatory,
professional and educational bodies; that it shall be regulated via legal, statutory or professional
authority; that there shall be a formal program of education; and that the specialty shall not limit
the right of the general practitioner to practice the full range of clinical dentistry. The frame for the
specialty within the 19 European countries seems rather homogenous regarding length, content
and examination. Details, however, vary considerably as well as the number of specialists related
to population and number of dentists. The specialty seems to have been more easily introduced
in countries with a well established public dental care system than in countries with mostly
privately organized dental care. Prosthetic dental care and oral rehabilitation has developed to be
a very important dental discipline involving high influence of quality of life, advanced
biotechnological techniques, much health related aspects, esthetic demands of the patients, great
variations between available methods for tooth replacement, high costs and thus great influence
on public as well as private investments. The time has come to enhance the specialty and EPA
needs to discuss if a European standard for specialist education and examination can be a ission
for the association, as it is for example within periodontology and orthodontics.

K16
KEYNOTE LECTURE
The impression in fixed prosthodontics: from the tradition to the new horizons
Enrico Gherlone*, Francesco Sanfilippo
University Vita Salute San Raffaele, Milan, Italy
The state of the art of recording anatomical information for fixed prosthodontics is considered in
this lecture. As a starting point, the traditional procedures for gingival sulcus conditioning before
impression taking are considered, followed by the evaluation of the most modern approaches
such as the use of non-invasive laser technology and new expansive impression materials.
Impression taking protocols, techniques (i.e. monophase-biphase impressions) and materials (i.e.
last generation polivinylsiloxanes), are reported in a simple way, but always with consideration for
the optimization of results. Finally, the outcomes of the San Raffaele Hospital prosthodontic team-
work experience are compared to those emerging from international scientific literature.

O01 - session: 1
ORAL
The reconstruction of edentulous maxilla and mandible with fixed prosthesis supported by
immediatelly
implants
Zdzislaw Bereznowski*, Maciej Dijakiewicz, Violetta Szycik
Department of Implantoprosthetics, Medical University of Gdansk, Poland
Immediate implant loading with fixed or removable complete dentures is more comfortable for the
patient in comparison to 2-stage surgical protocol. Discomfort, inconvenience and anxiety, which
characterize the period remaining to the second stage treatment were the incentives for patient
and dentist to apply the immediate loading procedure, accepted recently among clinicians.
Moreover, clinical experiences proved that immediate loading procedure can be the method
of choice. Our study aimed to present two methods of the immediate implant loading procedures.
In the first method one piece Nobel Direct implants were used. The implants were inserted
without the direct exposure of bone. The immediate temporary rehabilitation with fixed acrylic
bridge was implemented. The second method covered the immediate implant loading "All on 4'
system by Nobel Biocare. After three months of temporary rehabilitation, acrylic dentures were
exchanged for metallic-ceramic and acrylic bridges with metal reinforce, respectively. In both
cases we attained satisfactory results in function and esthetics.

O02 - session: 1
ORAL
Systematic reviews of survival of tooth and implant-supported FPDs
Bjarni E. Pjetursson1*, Ken Tan2, Niklaus P. Lang1, Urs Bragger1, Matthias Egger1, Marcel
Zwahlen1
1University  of Berne, Switzerland
2National   Dental Center, Singapore, Singapore
Objectives of this series of systematic reviews was to assess and compare survival of tooth and
implant supported fixed partial dentures (FPDs) and to describe the incidence of biological and
technical complications. An electronic Medline search complemented by manual searching was
conducted, to identify prospective and retrospective cohort studies on FPDs with a mean follow-
up time of at least 5 years. Patients had to have been examined clinically at the follow-up visit.
Failure and complication rates were analyzed using random-effects Poisson regression models.
The search provided 3658 titles, 211 abstracts and 81 full-text articles on tooth supported and
3844 titles, 560 abstracts and 176 full-text articles on implant supported FPDs. For tooth
supported FPDs 26 studies and for implant supported FPDs 21 studies met the inclusion criteria.
Meta-analysis of these studies indicated an estimated survival of conventional FPDs of 93.8%
(95% CI: 89.8%-96.3%) after 5 and 89.1% (95% CI: 81.0%-93.8%) after 10 years. The survival of
cantilever FPDs was 94.7% (95% CI: 91.2%-97.7%) after 5 and 81.8% (95% CI: 78.2%-84.9%)
after 10 years. The survival rate of implant supported FPDs was 95.0% (95% CI: 92.2%-96.8%)
after 5 and 86.7% (95% CI: 82.8%-89.8%) after 10 years. The survival rate of combined tooth-
implant FPDs was 94.1% (95 % C.I.: 90.2%-96.5%) after 5 and 77.8% (95 % C.I.: 66.4%-85.7%)
after 10 years in function. After 5-years, there was no significant difference in survival rates of
conventional, cantilever, solely implant supported and combined tooth-implant supported FPDs.
However, after 10 years the highest survival rate was found for the conventional FPDs (89.1%),
followed by implant supported FPDs (86.7%). Lower survival rates were found for cantilever
FPDs (81.8%) and for combined tooth-implant supported FPDs (77.8%) after 10-years of
function. Despite of a high survival of FPDs, biological and technical complications are frequent.

O03 - session: 1
ORAL
Longterm observation of mandibular overdenture supported by implants
Rolf Rosch*, Pawel Pazera, Regina Mericske-Stern
University of Berne, Switzerland
It was claimed recently, that two-implant mandibular overdentures were the standard of care for
edentulous patients (Feine et al. 2003). A variety of clinical studies reported on various treatment
outcomes with overdentures. The object of this study was to evaluate long-term (>10 years)
results of mandibular implant overdentures in elderly patients and to detect possible age related
problems. From 1984 to 1994 elderly edentulous patients received mandibular overdentures
supported by mostly 2 implants, according to the same treatment protocol. All of them closely
abided the maintenance care program and underwent at least one dental examination per year.
Annual records comprised systemic and oral health, medications, periimplant tissue conditions,
complications with implants and prosthesis, interventions and maintenance service. All data were
recorded and processed on computer. 151 patients with a mean age of 64.3 years at the time of
the implant treatment and a total of 130 implants were followed over 10 years. In 2004, the mean
observation period was 14.8 years and 44 patients were no longer available for clinical
examinations as they passed away (29), moved away (10) or dropped out for unknown reasons
(5). Altogether 13 implants were removed during the observation period; 9 implants were
replaced by new-ones. Biomechanical failures (loss of osseointegration) were more frequent
than periimplant infections. Distinct deterioration of general health was found in some patients
over time. Prosthetic complications decreased over time, with an increase towards the end of the
reported period. More problems were encountered with a resilient retention mechanism (clip bar
and ball anchors) than with a rigid bar. Implants may be stable over a prolonged time in elderly
patients. The reason for failures was mostly unclear, but one may speculate about some age
related etiology.

O04 - session: 1
ORAL
Immediate occlusal loading in mandibular fully edentulous patients
Piotr Majewski*, Krzysztof Gronkiewicz
Institute of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
In recent years dental implantology has become more predictable due to new implants, surfaces,
surgical techniques, new prosthetic components and solutions. Many authors report favorable
results of immediate loading of dental implants with success rate of 98% which corresponds with
standard protocol of 3 to 6 months of osseointegration. Dental implants that are immediately
loaded should have good primary stability and should be rigidly splinted after insertion.
Temporary acrylic bridge should be made within 48 hours of insertion. The authors presented
new surgical and prosthetic procedure of immediate occlusal loading of implants on the basis of
3i system. They described indications and contraindications for this technique and benefits of
offering patients immediate loading of dental implants.

O05 - session: 1
ORAL
Overdentures supported on implants - evaluation of a treatment results
Piotr Okonski*, Elzbieta Mierzwinska-Nastalska, Jerzy Gladkowski, Ewa Adamczyk-Sosinska,
Eugeniusz Spiechowicz
Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
Estimation of treatment results in the group of edentulous patients with complete lower
overdentures supported on implants. Surveyed group of 38 edentulous patients were observed
for five years. Implant stability was measured with Priotest. Chewing efficiency was evaluated
with Optocal test. Each subject was asked to chew the substitute of natural food for 60 cycles of
chewing and then all material was collected, dried and sewed in specially designed column of
sews. According to Rosin-Ramller's mathematic model the parameter d50 (mathematic
description of chewing abilities) was calculated. During each control visit, patients responded to a
questionnaire about comfort of chewing, speaking, denture stabilization, hygiene maintenance
and they also estimated the aesthetic results. Implant stability increased every year and after five
years the mean PTV value was -5,38. Chewing efficiency estimated once a year decreased
and at the end of a study was 40 % lower than it was at the beginning of the study. Surprisingly,
patients evaluated their comfort of wearing the dentures as very good, even five years after the
implant treatment. Comparison of the two types of overdenture retention (single ball attachment
and Dolder bar) revealed that surveyed patients from both groups similarly estimated the
treatment results and there were no statistically important differences in patients' chewing
efficiency and in implant stability. Prosthetic treatment with implant supported complete
overdentures markedly improved function of the dentures and increased comfort of life in the
group of edentulous patients.

O06 - session: 1
ORAL
Influence of angled abutments on stress distribution in various bone types
Volkan Asar*, Hande Ataman, Yavuz Burgaz, Celil Dincer
Faculty of Dentistry, Gazi University, Ankara, Turkey
Implant supported prosthetic considerations are routinely used treatment modalities to replace
missing teeth and related tissues. Although high success rates for a period of 5 to 10 years have
been demonstrated, bacterial infections and excessive stresses can lead to subsequent loss of
marginal bone and osseointegration. Bacterial infections can be minimized by placing implants in
aseptic conditions and providing sufficient oral hygiene. Abutment design and bone quality
around implants are very important factors that affect stress distribution around implants. Angled
abutments are generally used to overcome mechanical and esthetical problems due to improper
position of implants because of anatomical limitations. It has been indicated that angled
abutments can create higher stress values around implants than non-angled abutments. In the
literature that examines the influence of angled abutments on stress distribution, it is seen
that no one has taken into account the importance of bone quality around the implants. But bone
quality and quantity are very important success criteria. The objective was to evaluate the
influence of bone quality on the success of angled abutments. A mandibular segment was
studied. It had different bone types, in which implants that have angled abutments were modeled
with a personal computer, using a finite element program. We generated models that involved
four bone types (type 1, 2, 3, 4), each of which had four angled abutments ( 0°, 10°, 20°, 30° ).
Horizontal, vertical and oblique loads were applied to the occlusal surface of the abutments. We
evaluated the stress distribution in the bone around implants and compared the models with each
other. In our study we found greater stress concentrations as the values of the abutment angle
increased. Furthermore, we determined higher stress concentrations in the low-density
bone types. The highest stress values occurred in the cortical bone region of the type 4 bone
around the implant that had 30° angled abutment. Since greater stress concentrations were found
in the cases that had low-density bone type and high-angled abutment, these factors should be
taken into consideration while planning implant therapy.

O07 - session: 2
ORAL
A joint clinicostatistical study on the prevalence of Denture Stomatitis
Alcibiades Zissis1, Stavros Yannikakis2*, Alan Harisson3
1DentalSchool, University of Athens, Greece
2Department of Dental Technology, Technological Educational Institution of Athens, Greece
3Department of Oral and Dental Science, Bristol Dental School and Hospital, United Kingdom
Clinical experience and research have shown that complete denture wearing may result in
histopathological changes of denture bearing mucosa including denture stomatitis. The aim of this
joint clinicostatistical study was to determine any possible relationship between the prevalence of
denture stomatitis and factors involved in complete denture wearing and to compare this
prevalence between two groups. Denture wearers who attended the clinics of Dental School and
Hospital, University of Bristol, U.K. (group A) and the Dental School, University of Athens, Greece
(group B), were examined. The examination included a record with reference to sex, age, years
of complete denture experience, sets of dentures used, duration of last denture's usage, time
period of daily denture wearing and clinical examination of the upper denture bearing mucosa.
Data collected were analyzed using the chi-square test. Denture wearers of group A were older,
presented with greater experience in complete denture wearing, used more sets of dentures, the
majority used dentures exhibiting decreased vertical dimension of occlusion and wore their
dentures only in the day time. The prevalence of denture stomatitis was statistically significantly
different between groups A and B (27% and 39.7% respectively). In both groups the prevalence
of denture stomatitis was greater in females. In group B, the denture stomatitis prevalence was
significantly related to the years of denture wearing experience and the current denture's
usage. In both groups, continuous denture wearing was statistically highly related to prevalence
of denture stomatitis. This joint clinicostatistical study showed that two different population groups
of denture wearers presented similar profiles but their habits in complete denture wearing
differed. Comparisons between them indicate that proper denture wearing habits decreases
prevalence of denture stomatitis.

O08 - session: 2
ORAL
Denture stomatitis in type II diabetes mellitus - clinical and microbiological study
Barbara Dorocka-Bobkowska1*, Ejvind Budtz-Jorgensen2, Bogna Wierusz-Wysocka3, Wieslaw
Hedzelek1
1Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department of Gerodontology and Removable Prosthodontics, Université de Genéve, Switzerland
3Department of Diabetology, Poznan University of Medical Sciences, Poland
It has generally been assumed that denture stomatitis occurs with increased frequency in patients
with diabetes mellitus. The goal of the study was to evaluate the frequency and severity of this
disease in a studied group. 86 patients – acrylic complete denture-wearers suffering from type II
diabetes mellitus (T2DM) were compared with 58 patients with normal glucose metabolism
(control group). The patients with denture stomatitis were categorized according to the
classification of Newton. The prevalence of yeasts in the oral mucosa was estimated by culture
technique. All yeast isolations were identified by germ tube formation and by API 20C AUX
(bioMerieux). In vitro adherence of C. albicans to mucosal epithelial cells was assessed
according to the method of Darwazeh et.al (J Med Microbiol 33, 43-49, 1990). The patients
with T2DM had a significantly higher prevalence of denture stomatitis (60%) compared with
controls (36%), (p<0.01). Type II of denture stomatitis occurred most frequently among diabetic
patients, type I among non - diabetics. Candida albicans were the most frequently isolated yeasts
in both groups. Candida albicans showed a significant increased adherence to palatal epithelial
cells from diabetic patients compared with controls (p<0.001). The results were assessed,
using U-Gauss test and Student's t test, where appropriate. The results of the study suggest that
in T2DM there is a predisposition to Candida - associated denture stomatitis. These findings
should be taken into account during prosthetic treatment in the diabetic patients.

O09 - session: 2
ORAL
Helicobacter pylori infection and stomatitis prothetica hyperplastica
Bartlomiej W. Loster1*, Wladyslaw Bielanski2, Stanislaw Majewski1, Stanislaw J. Konturek2,
Witold Ziemniak3
         of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
1Institute
2Department  of Physiology of Collegium Medicum, Jagiellonian University, Cracow, Poland
3Gastrologic Center, Cracow, Poland
Toothless patients are usually treated with acrylic dentures which may cause inflammation of
mucous membrane of the oral cavity (stomatitis prothetica catarrhalis and stomatitis prothetica
hyperplastica [SPH]). The SPH type alterations may affect the denture bearing area, as well as
tissues adjacent to the denture. Recent literature indicates that the cause of SPH occurrence can
be attributed to inappropriate construction of denture baseplate which due to mechanical irritation
and/or large narrow baseplate causes such pathologies. It is common knowledge that
Helicobacter pylori (Hp) infection always causes inflammations of gastric mucosa resulting in the
development of gastric ulcer. It also creates the risk of gastric cancer. Most studies point to the
fact that pathologic alterations caused by Hp infection are not only limited to extragastroduodenal
manifestations. Hence the aim of this study was to determine possible dependence between
occurrence of chronic inflammations of oral mucous membrane and the Hp infection within the
abdomen. This study was carried out on 215 toothless patients (aged 46 to 89 years) among
them 129 females and 86 males. SPH was recognized in 30 patients using complete dentures.
Another 30 patients from the main group formed the control group. They never used dentures. All
examined patients underwent noninvasive diagnostics of active Hp infections by 13C-UBT
method. A uniform procedure of clinical dental examination was prepared and applied to all
patients. Moreover, endoscopic test of upper sections of the gastrointestinal tract was performed
to evaluate the state of mucous membrane of the esophagus, stomach and the duodenum. In all
patients (100%) with diagnosed SPH who underwent the examination, Hp infection of the
stomach was found. The endoscopic examination confirmed the mucous stomach membrane
inflammation in all patients, and in some also its damages: erosions, peptic ulcers, as well as
ulcer scars. The examination's results permit to state that Hp infection can be added to the list of
causes of SPH. It is recommended, when SPH is recognized, to carry-out the diagnostics of Hp
active infection, and after consultation with gastroenterologist, follow up with control endoscopic
examination.

O10 - session: 2
ORAL
The comparison of the condition of mandible between postmenopausal women with
different mineral status of
organism
Maria Golebiewska*, Ewa Kulikowska-Bielaczyc
Department of Prosthetic Dentistry, Medical University of Bialystok, Poland
The progress of the mandibular bone resorption is different for every individual and depends on
many local and systemic factors. The aims of the study were: to assess the influence of the
mineral status of the organism on the condition of the mandibular bone in partially dentate and
edentulous postmenopausal women, to define the effect of age and time after menopause on the
mandibular bone and the number of teeth present, to assess the interdependence of the
metabolic bone loss and the periodontal condition as well as the number of teeth and to evaluate
the usefulness of pantomography in detecting people with low bone mass. There was no
significant correlation between the metabolic bone loss and the resorption of the mandibular
alveolar ridge (IC/IM index) and the height of the mandibular cortex (PMI index) in both
partially dentate and edentulous groups. The age of the patient and the duration of menopause
did not affect the reduction of the mandibular bone and the number of teeth. The influence of the
generalized decrease in bone mass can be observed on pantomograms as porosity of the
endosteal margin of the lower border of mandibular cortex (MIC index).There was no significant
relationship between the metabolic bone loss and the periodontal status as well as the number of
teeth.

O11 - session: 2
ORAL
The influence of masticatory deficiency on gastric emptying in patients with dyspepsia
Teresa Sierpinska1*, Jan Dlugosz2, Maria Golebiewska1, Adam Chwiesko2
1Department   of Prosthetic Dentistry, Medical University of Bialystok, Poland
2Department   of Gastroenterology, Medical University of Bialystok, Poland
The frequency of dyspeptic complaints in human population is estimated to be 20-40%. The
causative role of Helicobacter pylori infection has not been proved. We are still looking for other
factors responsible for the occurrence of dyspeptic symptoms. The object of the study was to
examine the relationship between masticatory deficiency and gastric emptying in patients
suffering from dyspeptic complaints with respect to Helicobacter pylori infection. The study
was performed in 20 dyspeptic patients who were missing over 50% of their teeth and in 15
healthy completely dentate controls. The masticatory efficiency was measured using Optosil test
for 20 and 80 cycles of chewing. The occlusal plate was analyzed by means of the computerized
T-scan II system which registered the maximal force of pressure during the maximal occlusal
contacts and the time which passed between the first contact and the maximal force of pressure.
Gastric emptying of solids was assessed using the C13 octanoic test and the presence of
Helicobacter Pylori was determined on the basis of the C13 urease breath test. A higher
percentage of people infected with Helicobacter pylori was observed in the group suffering from
the lack of teeth compared with patients with a full dentition (e.g.69% v. c.g.59%) Gastric
emptying of solids was delayed in patients suffering from considerable lack of teeth without
occlusal contact and without the ability of food particles' reduction as compared to the controls
and patients with the lack of teeth but with occlusal contact (GEC I = 1,520, 45, GEC II =
2,170,25, GEC c.g. = 2,260,16). The lack of ability to break food into smaller particles may
affect the process of gastric emptying.

O12 - session: 2
ORAL
The influence of the active viral infection, chronic inflammation on the mucosal
overgrowth
Dorota Szubinska1, Andrzej Wojtowicz1*, Piotr Fiedor2
1Department   of Dental Surgery, Medical University of Warsaw, Poland
2Department   of Surgery and Transplantology, Medical University of Warsaw, Poland
The patients suffering from immunological deficiency have special needs during surgical-
prosthetics treatment. The aim of the work was the evaluation of the influence of chronic viral
infection and mucosal inflammation on overgrowth of oral mucosa in the patients with
immunological deficiency. Forty (40) patients were included and evaluated in this project, on
the base of detailed criteria: a) 20 patients with chronic immunosuppression treated with
Azatioprin-Cyclosporin (A-C) protocol, 5 years after organ transplantation with overgrowth of
gingival oral mucosa, b) 20 healthy control patients without immunosuppression with mucosal
overgrowth plicae. PCR, histological and immunohistochemical (HE, TGF beta, BMP6) study
were done twice with a 12 months interval for confirmation of viral infection. In two (2) patients
with A-C protocol, CMV, HCV infections with accompanying gingival-mucosal overgrowth were
found. Other eight (8) patients had CMV, HCV, HPV (4 patients) and HPV, HSV 1 (4 patients)
with accompanying gingival-mucosal overgrowth. The other ten (10) patients with A-C protocol
had no clinical pathological symptoms in oral mucosa. Six (6) healthy control patients (without C-
A), who used acrylic dentures, were infected with HPV, and clinical gingival-mucosal overgrowth
was observed. Other ten (10) healthy control patients had no pathological mucosal changes, but
they were infected with HPV, while the last four (4) healthy control patients had mucosal
overgrowth, but without viral confirmation. The results of the clinical, PCR and microscopical
study and their statistical correlation suggest, that HPV infection is a risk factor for gingival-
mucosal overgrowth formation. The preliminary observation shows, that immunosuppression and
acrylic irritation stimulate the susceptibility to viral infection (the increased number of infected A-C
group of patients). These factors stimulate connective tissue remodeling and formation of
gingival-mucosal plicae. The patients treated with immunosuppression constitute a special-needs
population. The special care includes interdisciplinary treatment: pathogen-control tests, and
possible advanced (implant) surgical-prosthetic treatment ie. acrylic-replacement therapy.

O13 - session: 3
ORAL
Remote symptoms in patients with compound temporomandibular joint disc displacement
Maria Kleinrok1*, Przemyslaw Kleinrok1, Beata Piorkowska-Skrabucha1, Janusz Kleinrok1,
Malgorzata Kostrzewa2,
Marzena Janczarek3
1Department of Prosthetic Dentistry, Medical University of Lublin, Poland
2Department of Children Radiology, Medical University of Lublin, Poland
3Department of Interventional Radiology and Neuroradiology, Clinical Hospital, Lublin, Poland
The current state of research indicates that signs and symptoms accompanying
temporomandibular joint disc displacement in the intercuspal position can be located not only
within the face and head but also within the entire motor system. Also vegetative and functional
signs and symptoms typical for fibromyalgia can occur in these patients. The aim of this study
was to explain the cause of remote signs and symptoms in patients with compound
temporomandibular joint disc displacement. Clinical investigations, magnetic resonance and
computer tomography imagings were carried out in 38 patients with compound
temporomandibular joint disc displacement. The patients were divided into two groups:
group I with and group II without remote symptoms in the motor system. In the diagnosis of the
condylar position in the intercuspal position on tomograms a method after Kleinrok, allowing a
simultaneous consideration of the condylar position in both joints and in three planes, was used.
Bilateral different condylar position in the intercuspal position, analyzed in three planes, was
significantly more often noted in group I than in group II (p<0,001). Besides, the index of
asymmetrical load of the temporomandibular joints in the intercuspal position after Kleinrok i.e.
the relationship of the number of TMJs pairs with asymmetrical condylar position to the number of
TMJs pairs with bilateral identical condylar displacement was applied in the analysis. The value of
the index was in group I 4,57, in group II 1,25. Local causative treatment of remote symptoms
was effective in 70,6%, in 23,5% an improvement was achieved. An excessive, asymmetrical
overload of the temporomandibular joints can lead to remote signs and symptoms in the entire
motor system in patients with compound temporomandibular joint disc displacement in the
intercuspal position.

O14 - session: 3
ORAL
The initial management of the temporomandibular disorders
Jolanta Kostrzewa-Janicka1*, Elzbieta Mierzwinska-Nastalska1, Artur Anulewicz1, Marek
Pratnicki1, Hubert Wanyura2,
Zygmunt Stopa2
1Department   of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Department   of Maxillofacial Surgery, Medical University of Warsaw, Poland
The masticatory system is important functionally with regard to speech, social interactions,
mastication and other oral function. Pain and dysfunction in this region can be a frightening and
disabling experience for patient, thus great attention must be paid to the initial treatment of
temporomandibular disorders (TMD). The aim of the study was to establish the effective method
of initial conservative treatment for different TMD subtypes. The group for this study
consisted of patients treated at the Department of Prosthetic Dentistry, Medical University of
Warsaw. The patients with underlying systemic or overt joint diseases were excluded. Patients
were divided into five groups with various TMD subtypes: myofascial pain group, myofascial pain
dysfunction group, internal derangement group, and osteoarthritis group. Treatment methods
consisted of: patient education, pharmacotherapy, physical therapy, splint therapy and occlusal
therapy. The management for each TMD type was established on the first visit. The treatment
efficacy evaluation was done after one week. In cases which did not show improvement another
treatment method was applied. It was found that it was necessary to apply a few methods
together to obtain improvement. Also, the differences in treatment methods used in various TMD
types were observed. It is very important to start the treatment with relief of symptoms, as it is
then easier to explain to the patient next treatment steps. It would be useful to establish the
management procedures for initial therapy. The clinical observation must be followed by rigorous
scientific evaluation: long - term study in randomized, controlled group.

O15 - session: 3
ORAL
Prevalence of oromandibular dysfunction (OMD) in adolescents in Lodz
Lukasz Pawlak1, Monika Sajewicz-Rosiak1*, Anita Wierzbicka-Ferszt1, Katarzyna Romanczuk-
Split2, Wojciech Split1
1Department   of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
2Department   of Prosthetic Dentistry, Medical University of Lodz, Poland
While the civilization makes great strides, new diseases are becoming more apparent. One of
these is oromandibular dysfunction (OMD) - a functional disorder in stomatognathic system as a
response to psychosocial stress. The subpopulation of adolescents during pubertal period of
lifetime is the most susceptible to stress. The aim of the study was to evaluate the prevalence of
OMD among adolescents. The participants were 2373 randomly chosen students (1431 girls and
942 boys) aged 13-19 attending one of the secondary schools in Lodz. The methods of
investigations were based on the questionnaire study and the clinical examination. The diagnosis
of OMD was made in accordance with the HIS, IASP and AAOP standards. The results obtained
were statistically analyzed using SPSS/PC system. OMD was diagnosed in 639 patients (26.9%)
including 421 girls ( 29.4%) and 218 boys (23.1%). The increased prevalence of OMD in
correlation with age was found: among girls from 22.5% in 13-year-old to 38.7% in 19-year old;
among boys from 19.6% in 13-year-old to 33.9% in 19-year-old. The most common symptoms of
OMD were: occlusal parafunctions in 35.7%, acoustic sounds in TMJ in 31.2%, limited jaw
opening in 30.8%. Pain on mandibular movements was present in 9.8% of evaluated subjects.
The OMD was present in the majority of the studied population of adolescents, more frequently
among girls than boys. The pain-free type of OMD was predominant. The prevalence of OMD
increased with age.

O16 - session: 3
ORAL
Psychical characteristics of functional-morphological disorders of the stomatognatic
system
Eliza Sobczyk1*, Halina Tejchman1, Zofia Majdanska1, Irena Leszczynska2
1Department      of Prosthetic Dentistry, Medical University of Gdansk, Poland
2Institute   of Maritime and Tropical Medicine in Gdynia, Medical University of Gdansk, Poland
Ones own predispositions; environmental and social conditions, the ability to cope in difficult
situations have a large impact on the etiology of functional- morphological disorders of the
stomatognathic system disorders. A particular influence on the formation of health behavior has
the period until 25 years of age. During this time all psychological elements are formed. It is a
time of emotional sensitivity, as well as susceptibility to positive behavior. The aim of this project
was to compare the results of the dental examination to psychological tests in student population
of AMG during 2003 and 2005. The groups tested were students (35 were picked randomly in
2003 and 2005). Dental examinations were carried out using Detailed Examination Cards.
Psychological testing was carried out using the NEO FFI tests which examined personality; PTS
test which examined nervous system type (temperament); test which measured the level of
mental health and its promotion, with regard to 4 ranges - conviction and expectations; health
behavior; value of health; coping with ailments. The carried out analysis of dental examinations
showed a considerable difference between the results in 2003 and 2005. The most important
difference were- TMJ dysfunctions- in 2003 22% in 2005 4.3%; teeth clenching - in 2003 70% in
2005 34.3%. Psychological tests indicated that individuals with medium to high level of
neuroticism, and higher temperament, more often had functional-morphological disorders of the
stomatognathic system. The tests showed a great individual range in conviction, expectation and
value of health. It is important to enlighten the patient that there is a connection between stress
and occlusional parafunctions, explain that one must control these parafunctions and inform the
patient of this connection. Often conversations between doctors and patients and use of
appropriate counseling skills by the professionals are the most important methods of diagnostics
and therapeutics.

O17 - session: 3
ORAL
The Treatment of pathological disorders in the facial nerve with electrostimulation and
kinesiotherapy - two
case studies
Anna Sojka1*, Juliusz Huber2, Agnieszka Wiertel-Krawczuk2, Wieslaw Hedzelek1, Alicja
Witkowska2
1Department     of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department     of Pathophysiology of Locomotor Organs, Poznan University of Medical Sciences, Poland
Both bruxism and fever infections developing in the mouth are often accompanied by pathological
changes in the efferent transmission of the facial nerve and myoarthropathic pains. The aim of
this study was to assess the improvement in the motor unit activity of the jaw muscles and the
transmission of the efferent fibers in facial nerve following kinesiotherapy and electrostimulation
treatment performed on two patients with the above disorders. Dental and neurophysiological
(electromyography and electroneurography, M-wave) studies were performed before and after
treatment in two patients. Patients suffered from lots of disturbances of dental (bruxizm and
infections) and neurophysiological origin. Ten sessions of regenerative facial nerve stimulation
and face muscles kinesiotherapy (frowning, sniffing and whistling; five times a day) were
performed. Neurophysiological studies showed the advanced unilateral neurogenic changes in
mandibular muscles and axonopathy in facial nerve before therapy. Following the therapy, a
significant improvement was found (together with myoarthropathic pains relief). Combined dental,
kinesiotherapeutic and electrotherapeutic treatment together with a precise and repeated
neurophysiological diagnosis provide good results in the treatment of temporomandibular
disorders.

O18 - session: 3
ORAL
Prevalance of muscle disorders in multiple sclerosis patients
Zoran Kovac*, Ivone Uhac, Daniela Kovacevic, Natasa Blecic, Renata Grzic, Miranda Muhvic-
Urek
Department of Dental Prosthetics, School of Medicine, University of Rijeka, Croatia (Hrvatska)
Multiple sclerosis (MS) is a complex neurological condition affecting sensory and motor nerve
transmission. Its progression and symptoms are unpredictable and vary from person to person as
well as over time. The purpose of this study was to assess the prevalence of muscle disorders
according RDC/TMD in Multiple Sclerosis patients. 50 subjects, 43 women and 7 men, with
definite MS according to McDonald's criteria participated in this study. The control group
consisted of 50 subjects who were matched according to gender and age with multiple sclerosis
patients. Assessment of extraoral and intraoral masticatory muscles was performed by means of
bilateral palpation for pain and tenderness according to the RDC/TMD specifications. According
to RDC/TMD criteria, 16 (32%) of the MS subjects had myofascial pain (MFP) and 1 (2%) in
control group. Result of x2 test show statistically significant difference between two groups
(x=15,95; p<0,001). In both groups none of the participants had diagnosis of myofascial pain with
limited opening. The Multiple Sclerosis group had a high prevalence of muscle diagnoses
compared to the controls.

O19 - session: 4
ORAL
Pressure variations under complete upper dentures with a palatal relief lined with silicone
elastomer
Pawel Piotrowski1*, Zdzislaw Krysinski2
1Department   of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
2Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
Inflammatory papillary hyperplasia (PIPH) is often observed on the mucosa of the palate exactly
in the area of the palatal relief. The authors assumed that the effect of reduced pressure was one
of the main factors predisposing to the development of PIPH and that the use of elastic materials
might help to reduce or eliminate it. The aim of this study was to determine whether there was a
significant difference in hydrodynamic pressure between two measuring points: in the middle of
the relief chamber lined with silicone elastomer and on the alveolar ridge. Sixteen patients took
part in the clinical tests. All of them were edentulous and all had palate inflammatory papillary
hyperplasia (PIPH). Each of them was provided with a new complete upper denture with a metal
base and a relieving chamber lined with silicone elastomer. Complete upper dentures were built
basing on the results of laboratory tensile and shear tests (Rocatec bonding system was applied
to fix silicone elastomer to a metal alloy). The variations in pressure were registered by means of
a special measuring system consisting of a specially prepared denture, a pressure transducer, an
electro manometer and a computer. The tests were carried out during static occlusion and during
the mastication of peanuts. Statistical analysis using the Mann-Whitney test did not show any
significant differences. This indicated that lining relief chambers with an elastic material probably
eliminated the irritating effect of reduced pressure and might eliminate one of the mechanical
causes of palatal inflammatory papillary hyperplasia (PIPH).

O20 - session: 4
ORAL
Multidisciplinary therapy of cleft patients
Marie Bartonova1,2*, Tatjana Dostalova1,2, Hana Hubalkova1
1Department  of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
2DMD,   Prague, Czech Republic
The number of children born with an orofacial cleft mirrors natality. In the Czech Republic the
long-term frequency of orofacial clefts is 2 per 1000 deliveries. The genetic register was
established in 1964 and at present includes more than 4500 families from Bohemia. The goal of
the study was to analyze systematically (case reports) patients with unilateral and bilateral clefts
which were treated orthodontically, surgically (including implant insertion) and prosthodontically.
The study focused on the indication of prosthodontic treatment using new trends and optimal
methods for improvement of esthetics, reconstruction of occlusion, bone reconstruction, therapy
speed, and stability of results. The study presented individual solutions in different cleft types
during the period from insertion up to ten years of function. The case reports demonstrate the
results of therapy. Ceramic materials are compared as a method of choice. Age at which the
patient was treated , esthetics , symmetry or asymmetry of dental arch and its influence on
occlusal shape were observed. Implantation age depended on bone growth termination. This
work reviewed the rationale and principles of treatment. Prosthetic reconstruction needs to be
individualized.

O21 - session: 4
ORAL
Estimation of adsorption of calcium phosphate to modified titanium surfaces
Barbara Sikorska1*, Wieslaw Hedzelek1, Ludwik Domka2, Leszek Kubisz3
1Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Technology Centre of Faculty of Chemistry, Adam Mickiewicz University of Poznan, Poland
3Department of Biophysics, Poznan University of Medical Sciences, Poland
The aim of the study was to evaluate calcium phosphate absorption to mechanically and
chemically modified titanium surface using Auger Electron Spectroscopy and to measure the
temperature dependent on electric conductivity. Medical titanium was the subject of analysis. The
mechanical treatment of subjected titanium pieces was carried out using two methods: sand -
blasting and polishing. Then the probes were subjected to acid - etching. The size of the titanium
implant surface area was estimated using a Scanning Electron Microscope and a profilometer to
measure the Ra parameter. In the further stage of the investigation in order to characterize the
calcium phosphate adsorption all the samples were subjected to incubation in simulated body
fluid (SBF). The calcium phosphate adsorption on modified surface is generally accepted as
giving an indication of biological properties of this surface. In practice, it expresses potential of
bone apposition to this material. After incubation the qualitative analysis with Auger Electron
Spectroscopy was carried out. This analysis showed the presence of calcium and phosphorus on
sand - blasted and acid – etched surfaces. There was no calcium and phosphorus on initially
polished samples independent of acid - etching procedure. The measurements of electric
conductivity were performed for the purposes of quantitative analysis. Both used methods
turned out to be appropriate for quantitative and qualitative measurements of calcium and
phosphorus on titanium surfaces.

O22 - session: 4
ORAL
The influence of sulphur reducing bacteria on the dental alloys surface
Justyna Otulakowska-Skrzynska1*, Anna Kedzia2, John W. Nicholson3
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department   of Oral Microbiology, Medical University of Gdansk, Poland
3University of Greenwich, Kent, United Kingdom
Bacteria are dominant microorganisms in the oral cavity flora and more than 90% of them are
anaerobic. Some of anaerobic bacteria produce hydrogen sulphide. Sulphur reducing bacteria are
also active in the oral cavity environment. The aim of this study was to investigate the in vitro
influence of sulphur reducing bacteria from the oral cavity on the surface of dental alloys. Ten
samples from high-gold, Ag-Pd, Cr-Ni, Cr-Co and Ti dental alloys were investigated. Fine
polished sample plates were individually placed in Scheadler's broth culture media (bioMerieux).
Microbiological material was taken from the bottom of pathological periodontal pockets from
patients suffering from advanced periodontitis. Prevotella intermedia was isolated and tested with
sulphurated hydrogen produce using gas chromatograph (Unicam Pro GC+). The control
samples were placed in the same culture media without bacteria and with inoculated bacteria
species which couldn't produce hydrogen sulphide. All groups of samples were incubated at 37°C
for 15 weeks in anaerobic conditions. The surface of each sample was then analyzed using
scanning electron microscopy and energy dispersive system microanalysis. Secondary electron
image was registered for each sample before and after test. Loss of luster on the surface of
samples was seen on macroscopic examination. Scanning electron microscopy revealed dark
discolorations on the surface of the samples placed in bacterial environment. There was no
difference between the samples placed in sulphur reducing bacteria culture and in bacteria
culture which did not produce hydrogen sulphide. Carbon was the main element found in thin
black spots on the surface of many samples and there was little or no sulphur in the deposit.
These effects were not observed in the control group without bacteria. 1. Bacteria culture media
can influence the loss of luster of the surface of dental alloys. 2. In conditions of this experiment
there was little or no sulphur in the deposits on the surface of the samples. 3. High level of carbon
deposit on the surfaces of the dental alloys samples is an indication of biocorrosion.

O23 - session: 4
ORAL
Infrared spectrophotometric identification of dental material released during mastication
Agnieszka Marcinkowska1*, Roman Wachowiak2, Wieslaw Hedzelek1
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department   of Forensic Medicine, Poznan University of Medical Sciences, Poland
The incidental release of a dental restoration or a spontaneous loss of a tooth structure fragment
during mastication frequently requires the lost fragment to be identified to confirm its origin. The
sequelae of incidental mechanical injuries caused by dangerous solid fragments present in the
mouth become crucial in case of habitual gum chewing. The problem involves identification and
differentiation of a restoration fragment or a tooth structure from incidental contaminations of
chewing gum originating in its production process. The studies were conducted using solid phase
infrared spectrophotometry in the range of 500 to 4000 wave number (cm-1) for quick
identification of commonly employed dental restorations. The data base of infrared transmission
spectra was prepared to provide a systemic reference system, useful in controversial
interpretation cases. The studies were performed on six groups of solid substances of organic
character filled with inorganic restorations (composite materials, compomers, fissure sealants)
and typical inorganic restorations (porcelain, amalgam). Natural chemical structure of permanent
teeth obtained from donors of various age provided the reference material. The measurements
were performed in a solid phase (KBr disk) using JR Bruker JFS 113 spectrophotometer
(Germany). The prepared database of infrared spectra included 30 most frequently employed
dental materials. Application of infrared spectrophotometry allowed for a quick differential
identification of typical dental materials produced from organic compounds for inorganic
restorations (porcelains) and of tooth structure-resembling fluoride apatites (Ca3(PO4)2 CaF2).
Chemical structures of dental restorations exhibit a specific intense infrared spectrum which
allows to identify typical functional groups. IR spectrum of dental structure differs radically from
those of synthetic restorations and is characterized by a scanty, low-intensity absorption, typical
for inorganic compounds resembling porcelain structure. Supported in part by WRIGLEY Poland
Sp. z o.o.

O24 - session: 4
ORAL
Acute phase reaction after complex treatment in refractory periodontitis
Anna Kurhanska-Flisykowska1*, Magdalena Sobieska1, Agnieszka Wasiewicz2
1Department   of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
2Poznan   University of Medical Sciences, Poland
Acute phase proteins may serve as a laboratory marker of cytokine network function: changes in
APP level reflect changes in cytokine balance and are easier to follow analytically. The acute
phase reaction was estimated in 32 patients aged 42-60, suffering from refractory periodontitis.
Among them, 27 had metallic prosthetic restorations. Along with selected clinical parameters (
CPITN, pocket probing depth, clinical attachment level, plaque index (OLeary) and BOP Index )
TAS and ochratoxin A (index of food toxicity) in blood serum, the markers of acute phase reaction
were measured. Concentrations of following proteins were measured using
immunoelectrophoresis acc. to Laurell: C-reactive protein (CRP), alpha1-acid glycoprotein (AGP),
alpha1-antichymotrypsin (ACT), transferrin (Tf), ceruloplasmin (Cp), alpha2-macroglobulin and
glycosylations profiles of AGP, ACT and Tf were estimated using crossed affinity
immunoelectrophoresis acc. to Bog-Hansen with Concanavalin A as a ligand. Results were
analyzed using STATISTICA 6.0 Software. It was shown that along with decreased TAS values
the concentrations of CRP and ACT were increased, showing intensive inflammatory reactions
(correlation coefficients r=-0.66 and -0.37, respectively). Parallel estimation of ochratoxin A
showed no significant correlation with acute phase proteins concentrations, though all values
were negative. This could suggest that external fungal infection and/or fungal toxins have no
influence on the inflammatory reaction occurring in mouth . Metallic applications seem to be
neutral.

O25 - session: 5
ORAL
Facial prosthesis with dental implants support
Jiri Holakovsky1*, Tatjana Dostalova2,3, Jiri Mazanek2, Hana Hubalkova2, Zdenek Nathansky1
   Faculty of Medicine, Charles University, Prague, Czech Republic
11st
2Department of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
3DMD, Prague, Czech Republic
Facial prosthesis with three dental implants is a method of choice in replacement of missing hard
and soft orofacial tissues. Prosthesis form, coloration, and texture must be as indiscernible as
possible from the surrounding natural tissues. Rehabilitation efforts can only be successful when
patients can appear in public without the fear of attracting unwanted attention. Dental implant
support gives the patient confidence in social settings. The goal of the study was to analyze
systematically patients with orbital surgical defects. The multidisciplinary therapy involved the
following disciplines: ophthalmology, maxillofacial surgery, implantology, and prosthodontics. The
case reports described: - orbital surgical defect after oncological process, - 3 dental implants
insertion localized in bone margin, - from 3 to 6 months healing period, - x- ray control and ball
attachments application, - facial prosthesis reconstruction. The position of ball attachments
helped to attain sufficient and stable retention of facial prosthesis. This work reviewed the
rationale and principles of treatment, which require individualized approach.

O26 - session: 5
ORAL
The prosthetic rehabilitation following malignant tumor surgery in maxillofacial region
Krystyna Rusiniak-Kubik*, Dariusz Rolski, Elzbieta Mierzwinska-Nastalska
Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
Recent advances in diagnostics, treatment methods and reconstructive surgery have greatly
expanded the cure rate for malignances of the oral cavity. The stomatognathic system of patients
after maxillofacial tumor resection and radiation resulted in functional disorders and
morphological deficiencies, and often posed unfavorable prognosis for successful prosthetic
rehabilitation. The study presents basic prosthodontic rehabilitation principles in the care of
patients after surgically treated tumors in the maxillofacial region. Special emphasis was placed
on multidisciplinary oral care and temporomandibular disorder therapy. Prosthetic treatment was
performed in several stages: with temporary appliances, occlusal splints, night guards and next
with dentures with inclined planes to create acceptable maxillomandibular relationship.
Myofunctional exercises and physical therapy were introduced in the introductory phase and
during prosthodontic treatment, as well as during the after-care period. Constructed partial or
complete postoperative cast chrome-cobalt dentures, overdentures, crowns and bridges with
precision attachments, provided the patients with the acceptable functioning. Prosthodontic
rehabilitation of the stomatognathic system of patients after maxillofacial tumor operations in
many cases could reduce the patients functional problems.

O27 - session: 5
ORAL
Options of prosthetic treatment - classical methods versus implants - case reports
Jindrich Charvat1*, Hana Hubalkova1, Tatjana Dostalova1,2, Marie Bartonova1,2
1Department  of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
2DMD,   Prague, Czech Republic
Successful rehabilitation of patients is based on optimal and individual treatment plan. The
diagnosis of dental conditions must be made, considering hard and soft tissues. Is then is
correlated with physical and psychological backgrounds and needs. The aim of the study was to
evaluate the therapy options - teeth and/or implant support, focusing on situations where dental
implants were contraindicated. The indication and contraindication of implants insertion is
demonstrated in the presented ten case reports. Based on ADA recommendations, a special card
was prepared which contained relevant information on the patients, including personal and health
history; the type of tooth; the type and location of the restoration; the type of therapy; the patient's
sensations; the material used; and photo documentation. Implants, fixed or classical removable
dentures were a valuable means of improving the appearance. The case reports demonstrated
the results of therapy. Recall examinations took place from 3 to 6 years. During those
visits materials were compared as a method of choice, age of treatment was discussed, esthetic
appearance of smile was evaluated, symmetry or asymmetry of dental arch and its influence on
occlusal shape were observed. Immediate loading was the method of choice. This work reviews
the rationale and principles of implants and classical prosthodontic treatment. Prosthetic
treatment requires individualized approach.

O28 - session: 5
ORAL
The influence of variable, low frequency magnetic fields on the bone tissue structure after
dental implantation
procedure
Paulina Klapcinska1*, Rajmund Orlicki2,3, Olga Tos3
1Medical University of Silesia, Katowice, Poland
2Department  of Stomatology and Biomaterials, Medical University of Silesia, Katowice, Poland
3Higher School of Dental Engineering, Ustron, Poland
The aim of the work was the reconstruction of the bone tissue after dental implantation
procedures and completed osseointegration of the applied implants. The process of bone healing
after these kinds of procedures is determined - among other things - by the patient's general
health and the chosen clinical method of performing the procedure. Both, drilling - which can lead
to overheating the bone, compression of its structure or vertical splitting of the alveolar process
represent a potential risk of complications making the process of healing the wounded tissue
much more difficult. To aid the process of bone tissue regeneration, the slow-variable, low
frequency magnetic field generated in Viofor JPS apparatus was applied before and after the
surgical procedure. The evaluation of the results was based on the DIGORA display system.
Apart from objective visual evaluation of the radiographs, the possibility of bone density
measurement offered by this system was utilized. Digora measures the pixel density value within
the marked area and next to the graphical form /GRAPH/ it shows the numerical values.
Densitometric measurements were performed owing to another program based on digital
radiography analysis. It enabled the evaluation of changes taking place in the investigated
material much earlier than by means of conventional X - ray photographs.

O29 - session: 5
ORAL
Titanium in Magnetic Resonance Imaging of Head and Neck Area
Hana Hubalkova1*, Zenon Starcuk2, Igor Linetskiy1, Jiri Mazanek1, Tatjana Dostalova1,3
1Department of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
        of Scientific Instruments, Academy of Sciences of the Czech Republic, Brno, Czech Republic
2Institute
3DMD, Prague, Czech Republic
In modern implantology, titanium is considered to be a material with optimal properties.
Improvement of strength characteristics of dental implants and surgical splints is provided by
casting pure titanium with other metals e.g. vanadium and aluminum. Commercially pure (c.p.)
titanium (grade 1) does not exhibit artifacts in MR images, but c.p. Ti (grade 4) may contain
traces of undesirable elements with positive magnetic properties. Even a slight amount of iron
present in implant material influences high frequency magnetic field of MRI device and so results
in visible image deformation. Artifact amplitude depends on magnetic properties of the material,
which depend on its composition and its homogeneity, object space orientation, magnetic field
intensity and the MRI protocol applied. The aim of the study was to determine magnetic
susceptibility and MRI compatibility of different titanium implant systems. Two groups of titanium
objects - (1) fabricated different dental implants and (2) individually cast samples of full metal
crowns in a real size and rods (4 mm in diameter, 25 mm in length) were tested both in vitro
experimental MR device (4.7T) and in human MR device (1.5T). Titanium material included c.p. Ti
(grade 1 - 4) and titanium alloys (with Al, V). Methods were based on gradient and spin echo
imaging experiment and results were compared with simulated data. Titanium materials tested
were characterized by different compatibility with MR environment. Based on the comparison
between the experimental and modeled data the values of magnetic susceptibility were
determined. The described artifacts were shown as deformations of examined structures. Non-
homogeneity of the magnetic field may also be associated with loss of image of the examined
anatomic region. Possible artifacts caused by ferromagnetic titanium materials may significantly
affect the quality of MR images with eventual misinterpretation of examination results.

O30 - session: 5
ORAL
Possibilities of restoring teeth in epileptic patients with mixed dental losses
Slawomir Pasiek1*, Maciej Szwankowski2
1Department   of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
2Department   of Prosthetic Dentistry, Medical University of Lodz, Poland
Prosthetic treatment in patients with epilepsy can pose problems connected with the necessity to
make fixed restorations in these persons. In the case of missing teeth, restorations are usually
made in the form of prosthetic bridges. However, in patients with mixed or even residual dental
losses, it is necessary to make fixed restorations, which are in fact strictly contraindicated in this
group of patients. The study presents examples of prosthetic treatment in epileptic patients with
mixed dental losses, using fixed and flexible restorations connected by precise retention
elements.

O31 - session: 6
ORAL
Multi-center research for shortened dental arch treatment in Japan
Yoshimasa Igarashi*, Yusuke Maruyama, Shuichiro Yamashita, Hideyuki Koike, Yuki
Matsuyama
Matsumoto Dental University, Nagano, Japan

O32 - session: 6
ORAL
Shape and size of dental arch - healthy, orthodontic and cleft patients
Tatjana Dostalova1,2*, Radek Hippmann1, Marie Bartonova1,2, Vladimir Smutny3, Miroslav
Peterka4
1Department    of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
2DMD,    Prague, Czech Republic
3Center for Machine Perception, Czech Technical University, Prague, Czech Republic
4Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
A new method of computer imaging and measurement on a dental stone cast is a ubiquitous tool
in dentistry and helps to record precise information. The objective of the study was to describe
the morphological and functional characteristics of each patient using specific guidelines. A
special device captured and geometrically calibrated images permitting comparison of several
different dental casts. Metric analysis of dental arch form was made. 837 sets of study casts were
screened - healthy (control group), orthodontic and cleft adult patients. Measurements of dental
arch width between reference points of canines, first premolars and first molars were made i.e.:
upper jaw: healthy men: 3-3 - 35.1 mm (SE 0.13); 4-4 - 37.5 mm (SE 0.13); 6-6 - 48.1 mm (SE
0.19); healthy women: 3-3 - 33.4 mm (SE 0.13); 4-4 - 35.6 mm (SE 0.15); 6-6 - 46.7 mm (SE
0.19); orthodontic treated men: 3-3 - 35.65 mm (SE 0.79); 4-4 - 37.7 mm (SE 1.07); 6-6 - 44.55
mm (SE 1.22); orthodontic treated women: 3-3 - 34.02 mm (SE 0.33); 4-4 - 35.2 mm (SE 0.50); 6-
6 - 43.4 mm (SE 0.53). Cleft orthodontic treated men: 3-3 - 35.00 mm (SE 1.41); 4-4 - 37.63 mm
(SE 1.90); 6-6 - 47.49 mm (SE 4.99); orthodontic treated women: 3-3 - 31.24 mm (SE 1.80); 4-4 -
35.93mm (SE 2.28); 6-6 - 46.12 mm (SE 0.89). Upper and lower arch compression in first
premolars and molars area were visible before treatment. Analysis of the arches did not
show significant differences between healthy, orthodontic and cleft patients after therapy. The
arch form width in men was larger than in women. Computer image monitoring can be used for
evaluation of dental arch changes. Orthodontic
treatment fully compensates the dental arch shape, size and form before possible prosthodontic
reconstruction including implants insertion.

O33 - session: 6
ORAL
Relative analgesia and the prosthetic management of the "gagging" patient
Mark Packer1*, Barry Lall1,2, Camilla Joarder2
1GKT   Dental Institute, King's College London, University of London, United Kingdom
2Community   Dental Department, Folkestone Health Centre, United Kingdom
Obtaining a stable and retentive denture base is a major factor in achieving a successful outcome
when providing complete or partial removable dentures. This is complicated when the patient
experiences difficulty with the impression phase of treatment due to a hypersensitive gag reflex.
Techniques used to manage this situation aim to encourage relaxation, control anxiety and
prevent panic attacks. Alternatively, the stimulus can be overridden by techniques such as
distraction and acupuncture to enable the performance of dental procedures. Relative Analgesia
(RA, inhalational sedation) may be employed to facilitate these procedures as this both, controls
anxiety and suppresses the gag reflex. To assess the efficacy of the technique in specialist
community dental practice. Three patients, who had previous failed attempts to produce a
satisfactory dental impression, were managed using a relative analgesia apparatus that delivers a
controlled nitrous oxide/oxygen mix. The patients were medically assessed and provided with
detailed pre-operative and post-operative instructions prior to the RA session. Waste gases were
effectively scavenged. The patients were monitored throughout the procedure and spoken to
gently throughout, as RA is fundamentally a semi-hypnotic technique. At the end of the procedure
the patients breathed 100% oxygen for 2-3 minutes, room air for 5 minutes and rested for
30minutes. In all three cases a successful impression was obtained. The maximum concentration
of nitrous oxide used for the procedures was 50%, the minimum 30%. All the patients felt relaxed
and were positive about the experience. Relative Analgesia may be employed to facilitate the
taking of dental impressions in patients with a hypersensitive gag reflex. The concentration of
nitrous oxide required to produce suppression of the gag reflex will vary from patient to patient.
This may be irrespective of size and weight; therefore each subject should be individually
monitored.

O34 - session: 6
ORAL
Prevalence of Combination Syndrome among geriatric denture patients
Honorata Krawczykowska1*, Halina Panek1, Ewa Kalecinska2
1Department   of Prosthodontics, Wroclaw Medical University, Poland
2Department   of Functional Disturbances of the Masticatory System, Wroclaw Medical University, Poland
The term Combination Syndrome (CS) introduced in 1972 by Kelly concerns patients who
simultaneously wear complete upper and partial lower removable dentures and still have their
natural anterior lower teeth. The clinical symptoms of this syndrome are: 1) substantial loss of
alveolar ridge bone in the anterior region of maxillae, 2) overgrowth of the maxillary tuberosities,
3) papillary hyperplasia on the hard palate, 4) loss of alveolar ridge bone under the removable
partial denture, 5) extrusion of the mandibular anterior teeth. The aim of the study was to estimate
the prevalence of Combination Syndrome among geriatric patients. Subjects of the study were 80
geriatric patients, treated in the Department of Prosthodontics, Medical University of Wroclaw,
from 1994 to 2005. The inclusion criteria for those patients were loss of all teeth in the maxillae,
preserved natural anterior lower teeth only and previous use of complete upper dentures. All
patients were examined clinically in order to confirm the presence or absence of CS symptoms
described by Kelly, as well as some additional symptoms introduced to the syndrome later by
Saunders. Thus, the prosthetic foundation was assessed taking into account the presence of ten
pathological symptoms. Moreover, the number and kind of lower anterior teeth left in the
mandible were established as well as the presence or lack of removable partial dentures in the
mandible. All of the Combination Syndrome symptoms described by Kelly were observed only in
six cases. In the majority of the studied patients only three symptoms were noted, some of them
were those introduced by Saunders. These were ubiquitous in different configurations. Among the
treated patients, the accumulation of particular symptoms in a single person was not observed,
regardless of presence or lack of the lower partial dentures.

O35 - session: 6
ORAL
Effect of crown material and cement type on heat transfer
Nesrin Anil, Canan Hekimoglu, Umut Cakan*
Faculty of Dentistry, Hacettepe University, Ankara, Turkey
Heat application to the dental tissues may cause reversible and irreversible necrotic changes.
The selection of restorative material is a major concern for protection of vital dental tissues from
the aspect of heat transfer. The aim of this study was to compare the temperature changes in
pulp chamber and root surface after application of heat to different restorations cemented either
with permanent or provisional cements. Thirty-six freshly extracted mandibular first and second
premolars were embedded in autopolymerized acrylic resin blocks and channels to pulp at
cemento-enamel level, midpoint and apex of the root were prepared. Test samples were
randomly divided into three groups. Full veneer crowns, metal ceramic crowns and all ceramic
crowns for each group were fabricated. Crowns were cemented with eugenol-free, zinc-oxide
eugenol temporary cement and glass ionomer cement. Samples were placed in a 37+/-1 °C water
bath and bath temperature was kept constant during the experiment. 5°C and 60°C water was
applied to the crowns and instant temperature change in the pulp chamber within first second was
measured with thermoelement. Temperature changes at pulp chamber, midpoint and apex of the
root were also consecutively measured one minute after the application of water. ANOVA and
Duncan tests were used for statistical comparisons. When crowns were cemented with temporary
cements, differences between the temperatures measured at pulp, midpoint and apex were non-
significant (p>0.05). Metal ceramic and all ceramic crowns cemented permanently, have similar
heat transfer properties. Full metal crowns were found significantly more conductive (p<0.05).
Restorative material and cement type may have influence on heat transfer to dental tissues.

O36 - session: 6
ORAL
Modeling and contact simulation of prosthetic restoration with tissues of stomatognathic
system
Anna Ryniewicz*, Wojciech Ryniewicz
Institute of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
The three-dimensional modeling and the simulation of function of the stomatognathic system
under the influence of load which were carried out on the stage of prosthetic construction allow
for resistance analysis of such solutions. The analysis was made by the visualization of the
stresses and displacement distribution in created therapeutic structure applied to the patient's
stomatognathic system. The presented procedure opened a possibility to optimize the strength
by the correction of the shape and suitable selection of materials. The computer programs used
in the modeling and analysis were applied in such a way as to allow for the analysis of the
prosthetic restoration's shape with the tissues of the stomatognathic system.

O37 - session: 7
ORAL
Preparation for testing psychometric properties of Hungarian version of OHIP
Gyula Szabo
Dental School, University of Pécs, Hungary
Orofacial health and function are important part of an individual's general health and quality of
life. Development and implementation of an instrument to measure levels of oral-health-related
dysfunction, disability and discomfort was very much in need in Hungary. The new Hungarian
instrument was developed according to general standards (Slade and Spencer 1994). The
original English version with 49 items (Oral Health Impact Profile, OHIP-E49) was translated twice
into Hungarian - first by a native Hungarian dentist and then by an official of the supervising
board. The corrected variant was again retranslated into English twice, under the control of the
supervising board, merged into one single second English variant and matched with the original
English version. The authors used a Hungarian variant with 49 items (OHIP-H49) matching the
English OHIP version (OHIP-E49) and one with 53 items (OHIP-H53) matching the German
variant (OHIP-G53). The short OHIP variant (OHIP-H14) was not translated separately. The
same 14 items as in OHIP-E14 and OHIP-G14 have been considered for OHIP-H14. Patient
groups were selected from clinical practices and regional lung screening stations to test validity,
reliability and responsiveness. From this preliminary study it was concluded that the translated
instrument seemed to meet the standard criteria and the Hungarian translation of the OHIP
-H49 scale could be considered as a scientifically sound tool to measure oral health and quality of
life in local inhabitants.

O38 - session: 7
ORAL
The evaluation of the muscles' relaxation influenced of the occlusal splint
Malgorzata Pihut*, Grazyna Wisniewska
Institute of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
In the course of functional disorder (TMD) an excessive increase of muscle's hyperactivity and
their asymmetry is observed. It causes pain and other dysfunction. One of the most important
goals of prosthodontic treatment is to obtain a physiologic level of muscles activity and their
symmetry. The purpose of this study was to evaluate the relaxation and asymmetry of masseter
and anterior temporalis muscle after treatment with three types of occlusal splint: stabilization,
repositing and NTI. Thirty patients, males and females, aged 18-34, with a clinical diagnosis of
pain dysfunction of the stomatognathic system qualified. They had to present a good general
health state, complete dental arches and limited degree of occlusal disorders. I group of patients -
10 persons with parafunctional activity was treated with flat plane interocclusal appliance, II
group- 10 patients with disc displacement with reduction were treated with repositioning splint
therapy, and III group- 10 subjects with accompanied headache - who were treated with NTI -
anterior guidance appliances. The investigations were made with 8-channel Electromyograph,
(Bio EMG II) which recorded electrical activity from muscle simultaneously. Bipolar, surface
electrodes were placed parallel to the muscle's fibers. The grounding electrode was placed on the
forehead. Microvolt signals were recorded during 4-second contacts in the position of centric
occlusion. The first record was made before the beginning of the treatment, the second- after 12
weeks of splint being in place. The results showed that the relaxation of the investigated muscles
and the decrease in imbalance between left and right muscle activity were different in all three
types of occlusal splints.

O39 - session: 7
ORAL
The assessment of mandibular movements in edentulous patients after exercises of
efficiency
Maciej Romanowicz*, Maciej Split
Department of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
In edentulous patients mandibular movements are disrupted as a result of limited proprioception
and changed force vectors of masticatory muscles. The rising question is: would it be wise to
incorporate the exercises of mandibular efficiency before prosthetic treatment? The aim of the
study was the assessment of mandibular movements in horizontal plane in edentulous patients
after exercises of efficiency. The subjects were twenty-four edentulous patients aged from
41 to 80 (12 females and 12 males) who had never undergone any prosthodontic treatment.
Mandibular movements in horizontal plane (the gothic arch) were drown using the Gerber system.
The mandibular movements were disturbed in every case. Changes in the gothic arch were used
to determine the study group. Three study groups (8 patients in each) were created according to
the tracings of gothic arch: absence of peak, flattened peak and peak displaced anteriorly.
Patients were asked to move the mandible forward, backward, to the left and to the right (in a
mirror),10 times each day for a period of 3 weeks. After first, second and third week of efficiency
exercises the gothic arch was recorded using the Gerber system. The qualitative and quantitative
evaluation of the gothic arch was undertaken. After 3 weeks of exercises the improvement of
forward movement was found in 12 patients (including 3 patients who did not have this movement
before), the improvement of lateral movement to the right was found in 21 patients (including 7
patients who did not have this movement before), the improvement of lateral movement to the left
was found in 20 patients (including 7 patients who did not have this movement before). In 12
cases the right angle and in 13 cases the left angle of the gothic arch increased. The multilinear
path tracing was observed in mandibular forward and lateral movements. Exercises of efficiency
affected mainly the improvement of lateral movements in edentulous patients. The exercises did
not have any influence on distorted neuro-muscular coordination.

O40 - session: 7
ORAL
Assessment of mandibular movements in edentulous patients
Maciej Split*, Agnieszka Homa, Wojciech Split
Department of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
Teeth loss causes deterioration in occlusal stability of stomatognathic system. Morphological and
functional changes have influence on masticatory apparatus function. As a result of
edentulousness, the proprioception from periodontium is disturbed. The clinical findings suggest
that these changes result in malfunction of mandibular movements. The aim of this study was the
assessment of mandibular movements in horizontal plane in edentulous patients. Forty-eight
edentulous patients aged from 41 to 80 years (26 females and 22 males) who had never
undergone any prosthodontic treatment participated in the study. Methods were based on clinical
findings (subjective and objective) and instrumental diagnosis using the Gerber system. Patients
with oromandibular disorders and degenerative changes in TMJ were excluded from this study.
Mandibular movements in horizontal plane (the gothic arch) were drown using the Gerber system.
The qualitative and quantitative evaluation of gothic arch was undertaken. The deteriorations in
mandibular movements in horizontal plane were found in every subject. In 5 patients the
protrusive movement was absent, in 43 patients it had a multilinear path tracing. In 11 patients
the lateral movement was absent. The regular lateral movement to the right was observed only in
2 patients, and to the left in 3 patients. Multilinear path tracing of the lateral movement was
present in the remaining subjects. The regular peak of the gothic arch was found in only 4
subjects. In 10 patients it was flattened and in 22 patients displaced anteriorly. In 12 patients it
was absent. In edentulous patients the mandibular movements in horizontal plane were
deteriorated. The disturbed coordination of these movements was predominant. The absence of
lateral movements and isolated opening movements were observed. The lateral movements are
frequently present from protrusive position of the mandible.

O41 - session: 7
ORAL
Assessment of mandibular movements in edentulous patients undertaking prosthetic
treatment
Agnieszka Homa*, Maciej Split, Wojciech Split
Department of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
As a result of complete teeth loss, the mandibular movements are disrupted. It is due to the lack
of proprioception from the lost periodontium. Since prosthodontic treatment does not provide a
new proprioception, the mandibular movements remain disturbed. The aim of the study was the
assessment of mandibular movements in patients undertaking prosthodontic treatment. Thirty-
three edentulous patients aged from 41 to 80 years (17 females and 16 males) who had gone
through prosthodontic treatment were evaluated. Methods were based on clinical findings
(subjective and objective) and instrumental diagnosis using the Gerber system. Patients with
oromandibular disorders and degenerative changes in TMJ were excluded from this study.
Mandibular movements in horizontal plane (the gothic arch) were drown using the Gerber system.
The qualitative and quantitative evaluation of the gothic arch was undertaken. The deteriorations
in mandibular movements in horizontal plane were found in every subject. The regular peak of the
gothic arch was found in only 4 subjects. In 24 patients the peak of the gothic arch was displaced
anteriorly, flattened in 4 subjects and absent in one case. The multilinear path tracing was
observed in every case. The regular lateral movement to the right was observed only in 2 patients
and remain multilinear for the rest of the evaluated group. The regular lateral movement to the left
was observed only in 4 patients and remained multilinear for the rest of 29 subjects. In dentulous
patients undertaking prosthodontic treatment the mandibular movements in horizontal plane were
deteriorated. The disturbed coordination of protrusive and lateral movements to the left was
predominant. In the majority of subjects, the lateral movements were present from protrusive
position of the mandible.

O42 - session: 7
ORAL
Cooperation between prosthetic and psychologist in curing "difficult patients"
Halina Tejchman1, Zofia Majdanska1, Eliza Sobczyk1, Irena Leszczynska2*
1Department      of Prosthetic Dentistry, Medical University of Gdansk, Poland
2Institute   of Maritime and Tropical Medicine in Gdynia, Medical University of Gdansk, Poland
The knowledge of patient's individual predispositions and psychological features allows for
planning of proper treatment, rehabilitation. One of the diseases, which have a great importance
on planning prosthetic treatment, is epilepsy. This disorder has a risk of traumas and degradation
of patient's general feeling. The other problem that occurs during prosthetic treatment in these
patients is the vomiting reflex, which makes appropriate treatment more difficult or impossible to
perform. It is often connected with excessive anxiety, social situations and patient's sensitivity.
The aim of the study was the evaluation of "difficult patient's" psychological predispositions and
taking this knowledge into consideration in planning therapy, rehabilitation and prophylaxis. On
the strength of selected cases the prosthetic treatment of patients with epilepsy and intensive
vomiting reflex were presented. Psychological test was performed using: test NEO-FFI, which
evaluated basic personality features, test PTS - type of nervous system, tests of measurement in
health promotion and psychology, which related to four ranges - convictions, -health behavior,
health estimating, struggling with disease. Performed prosthetic treatments were accepted by
patients and improved their psychical comfort. Psychological tests indicated that patients with
epilepsy showed increased level of neuroticism and fear, average type of nervous system with
advantage of stimulation processes, strong emotional control, low level of acceptation of the
illness and high sense of self - efficacy. In patients with intensive vomiting reflex the results
evidenced very high level of neuroticism, very weak nervous system with advantage of
stimulation processes and low emotional control. The knowledge of individual psychological
predispositions of evaluated patients allowed to determine their psychological conditions, assign
proper treatment and rehabilitation. Noting the close connection between psychological condition
and illnesses, as well as good cooperation with the dentist allows for better results of curing and
even spontaneous recovery.

O43 - session: 8
ORAL
Evaluation of the utility of anthropometric parameters in predicting the width of maxillary
anterior teeth
Gloria Staka1*, Agron Rexhepi2 Dugagjin Sokoli1,
1Department      of Prosthodontics, Dentistry School, Medical Faculty, University of Prishtina, Kosovo-UNMIK, Yugoslavia
2Institute   of Sports Anthropology, Prishtina, Kosovo UNMIK, Yugoslavia
In the absence of pre-extraction records, various types of parameters, including anthropometric
ones, have been used to predict the width of the maxillary anterior teeth for complete dentures.
This study was undertaken to evaluate the utility of anthropometric parameters for this purpose.
One hundred sixty dentate Kosovar subjects (80 males, 80 females; mean age 23 years) free
from facial and dental deformities were included in this study. The set of 12 anthropometric
variables (sagittal cranial diameter, head breadth, head height, head circumference, facial length,
bizygomatic width, intercanthal width, interalar width, philtrum width, intercommissural width,
interbuccal frenum distance, bigonal breadth) and the width of the maxillary anterior teeth
(WMAT) as a dependent variable were measured according to the International Biological
Program. Basic statistic parameters and multiple regression analysis were calculated. In male
subjects a multiple correlation coefficient was R = 0.521; R 2= 0,272, = 0,02. Prediction of the
width of the maxillary anterior teeth in males can be done through the saggital cranial diameter
(= 0.33, t = 2.20, = 0.03) and the interbuccal frenum distance (= 0.33, t = 2.20, = 0.03). In
female subjects a multiple correlation coefficient was R = 0.501; R2 = 0,251, = 0,03. Prediction
of the width of the maxillary anterior teeth in females can be done through head height (= -0.26,
t = -2.07, = 0.04) and interbuccal frenum distance (= 0.28, t = 2.16, = 0.03). Within the
imitations of this study, these results suggest that for the width of the maxillary anterior teeth in
male subjects the best model of predictor variables was sagittal cranial diameter and interbuccal
frenum distance, while in female subjects the best model was head height and interbuccal frenum
distance.

O44 - session: 8
ORAL
Morphometric analysis of mandible head morphometry
Jurand Mackiewicz*, Maria Prosba-Mackiewicz
Department of Prosthetic Dentistry, Medical University of Gdansk, Poland
Functional disorders of stomatognathic system are currently very common in society. Modern
diagnostic methods are based on the assessment of temporomandibular joint topography . The
aim of the work was to analyze morphometric parameters of the mandible head. The study was
performed on 60 human mandibles, which in relation to maxilla had at least one support area on
both right and left side. Angles of inclination in frontal and saggital planes, as well as long and
short axis were measured. Indirect and direct measuring methods were used. Results were
statistically analyzed As the end conclusion no significant disproportions of analyzed parameters
was observed between the left and the right side. Obtained results allow us to suggest that
symmetrical presence of support areas may be one of the modulating factors of anatomical
structures of temporomandibular joint.

O45 - session: 8
ORAL
Metallic and acrylic dentures base plate and phonetics
Florije Asllani-Hoxha*, Agim Islami, Enis Ahmedi, Kujtim Shala
Department of Prosthodontics, Dentistry School, Medical Faculty, University of Prishtina, Kosovo-UNMIK, Yugoslavia
Speech is a very complicated process, which can be essentially influenced by a small
modification of an individual, shared component. The aim of this study was the assessment of
voice resonance in complete denture wearers, while articulating specific palatal consonants and
vocals, according to constructive material of base plate of complete denture after a known period
of adaptation. Data were collected using a questionnaire as a subjective method completed by
patients, and with objective method-voice recording with a computer assisted frequency analysis.
Sampling criteria: patients with edentulous upper jaw with favorable retentive supportive tissue,
and with voice dependable profession. N=30 divided in two groups. Group 1 with acrylic base
plate; Group 2 with metallic base plate, whereas other potential variables with possible impact in
phonation, were constant. Sound was recorded digitally with software Sound Forge 6.0, Sonic
foundry, Inc. specifically modified for this purpose. Collected data were examined by spectrum
analyses of Frequency(Hz), Decibels(dB) and FFT bin, and statistically analyzed by ANOVA two-
factorial method. Sonogram of the examined group with metallic base plate as alternative to
acrylic, indicated significance in pronouncing of consonants. Higher degree of significance was
found during pronunciation of long vocals as I, U, O, Ë, A, randomly used by Albanian speaking
population. Metallic base plate showed better resonance effect of oral cavity versus acrylic base
plate, based on acoustic quality of metal as material, and due to thin layer of 0.9 mm, which did
not interfere with buccal anatomic resonator. The authors consider that the presented method can
be used routinely in dental practice.

O46 - session: 8
ORAL
Inlay-onlay bridges in the prosthetic treatment of single missing teeth
Tomasz Kondracki1*, Maria Golebiewska2
1Art   Dental, Warszawa, Poland
2Department     of Prosthetic Dentistry, Medical University of Bialystok, Poland
Prosthetic treatment of single missing teeth, especially in anterior sides of dental arch, is one of
the most difficult aspects in prosthetic dentistry. Inlay-onlay bridges as mildly disabling
restorations offer good quality retentions, preserve pulp vitality and provide natural aesthetics of
supporting teeth. The aim of the research was the evaluation of successes, failures and
complications criteria in inlay-onlay bridges as the choice of prosthetic treatment of single missing
teeth. 29 patients (18 F, 11 M), middle age 40,9 years (S14,4) were treated with 33 inlay-onlay
bridges (23 classical and 10 mixed inlay-onlay). 26 single missing teeth were restored in the
maxilla and 9 in the mandible - 16 on the anterior sides and 19 on the posterior sides of dental
arch. Observation period lasted from 6 to 96 months. During a 5-year clinical follow-up period,
cumulative success ratio was 100%. Some complications were noted in clinical evaluations
during the first year after cementation - they concerned supported teeth as temporary pulp
hypersensibility to cold (2 cases), temporary hypersensibility during mastication (1 case),
secondary caries cavity (1 case) and also 1 case of metal framework deformation and 1 loss of
cementation. 25 subjects were very satisfied with the restorations, while 8 patients stated that
they were moderately satisfied. Traditional inlay-onlay bridges as prosthetic treatment of
single missing teeth match up to the requirements of advanced aesthetic and non-invasive
dentistry and do not require lengthy treatments and extensive means as compared to single-
implant restorations.

O47 - session: 8
ORAL
Evaluation of the effect of local anaesthesia on blood flow in the dental pulp of vital teeth
Slawomir Pasiek
Department of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
Local anesthesia allows carrying out dental procedures in pain free conditions. Different
techniques can be used to administer anesthetic agents, thanks to which the area of tissues
under analgesia varies, depending on the extent of the conducted procedures. The commonly
used analgesic solutions, apart from the proper analgesic compounds, contain vasoconstrictors,
conservants, as well as stabilizers. Vasoconstrictors prolong the action of anesthesia, but on the
other hand they can have negative effects on blood supply to the tissue. This temporary
impairment of blood flow can cause reversible and irreversible changes in the pulp of
desensitized teeth. The aim of the study was to assess which type of local anesthesia and which
anesthetic agent caused the biggest changes in blood flow in the dental pulp. The study included
30 patients aged 20-40 who received anesthesia during the conducted dental procedures. They
were divided into three groups, each consisting of 10 persons. In each group anesthetic agents
were administered using one of the following three methods: infiltration-submucosal,
intraperiodontal or infiltration-periductal. Each patient was anesthetized four times with 2%
lidocaine with adrenaline 1:100000, 3% mepivacaine, 4% articaine with adrenaline 1:200000 and
4% articaine with adrenaline 1:100000. Changes in blood flow were measured with a laser
Doppler flowmeter and the degree of depth of anesthesia with an electrical tester evaluating the
vitality of the dental pulp. On the basis of the conducted studies it was discovered that the biggest
disorders in blood flow in dental pulp occurred when the intraperiodontal method was used to
administer anesthesia and smallest in the infiltration-periductal method. Among the four
anesthetic agents the longest lasting changes in blood supply to the dental pulp occurred under
the influence of 2% lidocaine with adrenaline 1:100000.

O48 - session: 8
ORAL
Chewing forces and methods of measurement in stomatognathic system
Bartlomiej Pawlus1*, Rajmund Orlicki1,2, Janusz Juraszek1
1Higher   School of Dental Engineering, Ustron, Poland
2Department   of Stomatology and Biomaterials, Medical University of Silesia, Katowice, Poland
Bite force examination concerns chewing efficiency estimation. It is important in planning
prosthetic, orthodontic and surgical treatment. In prosthetic restoration projects, it allows to obtain
a balanced force distribution on bony base using natural abutments and implants. In the 17th
century, Borelli described bite forces measurement using his own instrument. Measuring methods
were later modified by successive investigators. Nowadays, measurement instruments based on
piezoelectric and tensometric phenomena are used in statical and dynamical system. In
tensometric instruments we use electric resistance change which arises as a result of pressure
on gauge. However, in piezoelectric instruments to measure the applied force a quartz transmitter
is used. It generates a difference of potentials on external surfaces of the crystal. Next, we can
measure this difference. The methods mentioned above are used to estimate chewing forces
before, in the middle and after orthodontic and implantoprosthetic treatment.

O49 - session: 9
ORAL
The comparative analysis of the fit of gold, chromium alloy and precision laser welding
cast titanium
frameworks
Dagmar Kudrnova1*, Marie Bartonova1,2, T. Chlubna1, Tatjana Dostalova1,2
1DMD,   Prague, Czech Republic
2Department  of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
Conventional lost-wax techniques to fabricate implants have been found in vitro to be imprecise
and inaccurate when judged by passive fit requirements. This may be attributed to distortion that
occurs during the cooling phase of the casting or results from the inadequate laboratory
procedure. The aim of this work was to present clinical comparison of passive fit of frameworks to
prevent the stress transfer from bridge to implant-bone interface. Three different techniques
were compared: gold, chromium alloy and precision laser welding cast titanium framework. An
impression and master cast was fabricated. Record jaw relations and make articulator
installations were prepared using conventional techniques. The lost-wax casting method was
used for gold, chromium alloys and titanium (including titanium welding) framework fabrication.
Passive fit was checked in the master cast and human mouth. X-ray image and screwing analysis
were analyzed. Position of implants was compared. Disparallel implants position could only be
reconstructed with cutting construction and laser welding technique.

O50 - session: 9
ORAL
Effect of Post-Core Materials on Final Color of In-Ceram, IPS Empress
Gulay Uzun1, Gurel Pekkan1*, Sema Altunsoy2, Filiz Keyf3
1Hacettepe  University, Ankara, Turkey
2Kavaklydere  Bayyndyr Hospital, Ankara, Turkey
3Faculty of Dentistry, Hacettepe University, Ankara, Turkey
In this study, the effects of ceramic, chromium-nickel (Cr-Ni) and ceramic opaque sinterized on
chromium-nickel (Cr-Ni+opaque) post-core materials and different colored (opaque white, white,
yellow and brown) cements on final color of all-ceramics materials (In-Ceram, IPS Empress and
IPS Empress II) were investigated. Three groups of post-cores (ceramic, Cr-Ni and Cr-
i+opaque), 10 samples per each group, were prepared as discs 140.5 mm in diameter and 1.5
0.05 mm in thickness. Additionally, a total of 40 cement samples, 10 per each group (opaque
white, white, yellow and brown) were prepared as discs 140.05 mm in diameter and 0.10.01
mm in thickness. One sample of three different dental ceramics (In-Ceram, IPS Empress and IPS
Empress II) was prepared as discs in similar dimensions. The effect of post-core materials was
evaluated on the final color. In each group, while one cement color and one all ceramic material
remained constant, 30 post-core specimens which prepared 3 different materials were studied. A
total of 36 groups were established, in which each group contained a post-core, a resin cement
and a ceramic disc. The color configurations were assessed with 396 measures with a
colorimeter per each group. Cow dentin was placed instead of post-core materials for control
samples and measured with a colorimeter. In the evaluation of post-core materials: for the In-
Ceram system, all three post-core materials were found to be within clinically acceptable limits
(EDEDE<2).

O51 - session: 9
ORAL
A long term study on residual monomer release from denture materials
Alcibiades Zissis1*, Stavros Yannikakis2, Gregory Polyzois1, Alan Harisson3
1DentalSchool, University of Athens, Greece
2Department of Dental Technology, Technological Educational Institution of Athens, Greece
3Department of Oral and Dental Science, Bristol Dental School and Hospital, United Kingdom
Heat and auto polymerized acrylic resins are routinely used in every day prosthodontic practice
despite of their shortcomings to ideally meet the physicomechanical and biological requirements.
It has been widely reported that residual monomer levels produce not only negative effects on the
mechanical properties of denture bases but also are associated with mucosal reactions. The aim
of this long-term study was to investigate the release of residual monomer from different denture
materials, for 38 months after curing and storage in water. Specimens made of four denture base
resins (three heat polymerized, one auto polymerized) and one hard liner were subjected to
residual monomer determination using gas liquid chromatography. The residual monomer
estimation was carried out on three occasions: one week, 12 months and 38 months after curing.
The data obtained were analyzed using two-way Anova followed by Scheffe's test for post hoc
multiple comparisons at =0.05. Heat polymerized denture base acrylic resins showed less
residual monomer than auto polymerized ones (p.05), during the 38 months storage time period.
Auto polymerized denture materials, which had higher residual monomer content, released
statistically significant amounts of monomer (p 0.05). Heat polymerized denture base acrylic
resins released insignificant amounts of residual monomer during the storage period; whereas
both the auto polymerized denture base resin and the hard liner released significant amounts of
residual monomer during the initial storage time period but insignificant ones during the rest of the
storage period.

O52 - session: 9
ORAL
The influence of CO2 laser beam on chosen dental materials
Piotr Andrysiak1*, Zdzislaw Blaszczak2, Wieslaw Hedzelek1
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department   of Optics, Faculty of Physics, Adam Mickiewicz University of Poznan, Poland
Carbon dioxide laser is designed mainly for soft tissue surgery. In prosthodontics, this type of
laser is used usually for prosthetic area preparation. Understanding interactions of lasers with
some materials used during dental treatment is necessary because of a possible risk of
accidental contact with adjacent teeth. The aim of the study was to evaluate carbon dioxide laser
potential impact on chosen dental materials. The studies were performed on six groups of
materials: acrylic resin, porcelain fused to metal (PFM), composite materials, bis-acrylic material
for temporary crown and bridges, Cr-Ni alloy and titanium alloy for intraosseous implants. Each
sample was fixed in a focus distance and irradiated for 0.5 s with CO 2 laser beam in continuous
wave work conditions. The power for each material was set to be 0.5; 1.0; 2.0; 4.0 and 8.0 Watts.
Then the structural changes were measured by optical comparator (type 1.00037 Carl Zeiss Jena
-Germany). The observed structural changes were different depending on the material sample.
For non-metallic samples a variety of surface changes were noticed. PFM showed crackings,
mainly, from 0.313 to 0.676mm in diameter. In acrylic resin regular-edged crater formation was
observed. The diameters measured were evaluated to range from 0.741 to 0.906mm. Similar
structural changes, like charring and melting, were observed both in composite and bis-acrylic
materials. The size of the damaged areas varied from 0.587 to 0.871mm. For both Cr-Ni and
titanium alloys no damage was noticed. CO2 laser beam for soft tissue procedures should be
applied with utmost care not to affect adjacent dental materials. Its applications can cause a
variety of structural changes like crater formation, melting, charring, cracking. Laser conditions
applied in this study did not evoke any optical changes in metallic samples, which was probably
due to a large thermal capacity of metal on one hand and to a relatively short time of applications
on the other.

O53 - session: 9
ORAL
An investigation of the accuracy (inaccuracy) of refixing broken teeth to stone casts
Peter Likeman1*, George Paolinelis2
1GKT   Dental Institute, King's College London, University of London, United Kingdom
2Department   of Biomaterials Sciences, GKT Dental Institute, King's College London, University of London, United
Kingdom
A not infrequent accident with casts intended for the construction of partial dentures is the
fracture of a tooth: usually isolated single teeth, often elongated by gingival recession. The
fractured tooth is often repaired with cyanoacrylate adhesive and everything proceeds as if
nothing has happened until the framework does not fit. The purpose of this study was to measure
the error in fracturing and repairing teeth on stone casts. The XYZ coordinates and angulation of
35 teeth on five casts were recorded using the Triclone 90 (Renishaw) contact scanner. The teeth
were then fractured and repaired using cyanoacrylate adhesive and the casts were scanned
again to show differences in the position of the fractured tooth. Results for 35 fractured teeth
showed the mean discrepancy in repositioning the repaired teeth in the XY plane was 0.18 mm
and the mean change in angulation 0.5 degrees. These results confirm that fractured and
repaired casts should never be used for denture construction

O54 - session: 9
ORAL
Staining techniques - comparative histological studies on human and bovine enamel
Bogdan Miskowiak1, Teresa Matthews-Brzozowska2,3, Katarzyna Mehr4*
1Poznan University of Medical Sciences, Poland
2Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
3Department of Dentofacial Orthopedics and Orthodontics, Wroclaw Medical University, Poland
4Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
Human and bovine dental enamel is frequently employed in dental experimental studies. In view
of the composition of enamel, staining techniques used for histological examination should allow
for observation of both its inorganic and organic components. The studies aimed at defining the
optimum staining techniques for tooth sections, which enabled evaluation of the condition of the
enamel and provided the potential for comparing the patterns of human and bovine enamel. The
material consisted of 800 sections of the crowns of human and bovine permanent teeth of various
functional groups, both erupted and unerupted. Tooth sections were examined and stained with
use of various techniques (azane, picric acid, hematoxylin+picric acid, hematoxylin, eosin,
fuchsin, H+E, Mallory). The patterns revealed were analyzed under a Nikon Eclipse E600 optical
microscope, coupled to a computer with MicroImage 4.0 software and the data were subjected to
statistical analysis. The staining techniques employed were variably effective in their
demonstration of inorganic and organic enamel structures. Human and bovine teeth resembled
each other in respect to the manifestation of parazonium and diazonium but comparison of
patterns noted at the same magnification detected differences in prism sizes. However, the
enamel of the two species showed differences in the number, location and size of lamellae, tufts,
spindles, bulbs and spheroids. 1. Staining of enamel in human and bovine teeth demonstrated
both inorganic and organic structures; 2. The histological patterns obtained in this way provided
the potential to detect differences in the structure of occlusal and masticatory surfaces, enamel
width, and the number, location and size of organic structures; 3. It seems that results of
experiments performed on lateral permanent human and bovine teeth may significantly differ
between the two species.

O55 - session: 10
ORAL
Evaluation of the mechanical properties of different all-ceramic systems
Handan Yilmaz, Cemal Aydin, Esma Basak Gul*
Gazi University, Ankara, Turkey
The esthetic all-ceramic crown materials have challenged the traditional porcelain fused to metal
crowns. One of the primary goals of dental ceramic developers and engineers has been
improving the strength characteristics of the materials. Various mechanisms are used for
strengthening dental ceramics in order to improve their clinical instrumentality. Today, new
zirconium ceramic materials are on the market. The mechanical properties of high-performance
zirconium ceramics make them interesting as potential candidates for all-ceramic restorations in
high stress-bearing areas. The purpose of this study was to evaluate and compare the most
significant mechanical properties of 6 different all-ceramic core materials, (in-ceram alumina,
empress II, finesse, cergo, cercon and inceram zirconium) namely the biaxial flexural strength
(according to ISO 6872) and the fracture toughness tests. The materials used in this study were
In-ceram alumina (Vita, Germany), IPS Empress2 (Ivoclar, Vivadent, Switzerland), Finnesse
(Ceramco, Germany), Cergo (Degudent, Germany), Cercon (Degudent, Germany) and Inceram
Zirconia (Vita, Germany). 20 specimens with a diameter of 15 mm and 1.2 +/- 0.2 mm. width were
prepared from each of the materials according to the manufacturers' recommendations. In the
biaxial flexural strength test, the disk specimens were positioned on three balls and loaded only in
the middle. For the indentation fracture toughness test, a greater force must be applied than the
biaxial flexural strength test in order to form cracks with Vickers hardness indenter. The results
were gathered, analyzed and evaluated by statistical analyses.

O56 - session: 10
ORAL
Effect of Pontic Type and Occlusal Form on the Fracture Strength of Fiber-reinforced
Inlay-retained FPDs
Mutlu Ozcan*, Marijn Breuklander
Faculty of Medical Sciences, University of Groningen, Netherlands
Direct fiber reinforced composites could be time consuming due to incremental build up and
polymerization of each layer in clinical conditions. The objectives of this study were to compare
the fracture strength of a) direct inlay retained fixed partial dentures (FPD) built up using 3 types
of prefabricated pontics as well incremental composite build up and b) to compare the effect of
pontics with various occlusal forms on the fracture strength. Direct inlay retained FPDs (N=40,
10/per group), reinforced with E-glass fibers (everStick, Sticktech, Finland) were prepared
between mandibular first premolars and first molars using a resin composite (Clearfil Photo
Posterior, Kuraray). Slots were prepared using conventional inlay burs (Cerinlay), small and large
ultrasonic tips (SONICSYS approx). Pontics were made in 3 ways using a) Natural tooth (Gr1), b)
Acrylic denture tooth (Gr2) c) Porcelain denture tooth (Gr3) d) Composite incremental
built-up (Gr4). Also 3 types of occlusal platforms (N=30, 10/per group) namely, a) Shallow, b)
Deep, c) Elliptic were prepared with the aid of steel balls on fiber reinforced composite bar
specimens. The specimens were kept in water at 37sC for one month prior to fracture test
(universal testing machine, 1mm/min). No significant difference (P>0.05) was found between Gr 1
(543162 N), Gr 2 (539301 N), Gr 3 (509151 N) and Gr 4 (598240 N) in final fracture
strength (ANOVA). The occlusal form however showed significant influence (P<0.001). Deep
occlusal pattern demonstrated significantly lower mean fracture strength (800 N) than those of
shallow (1650 N) and elliptic (1620 N) occlusal patterns of the pontic. Prefabricated pontics could
be used in conjunction with glass fibers however occlusal form plays a more significant role on
the strength of fiber reinforced restorations.

O57 - session: 10
ORAL
Modification of the surface of aramid fibres as reinforcement acrylic resins
Przemyslaw Gajdus1*, Wieslaw Hedzelek1, Ludwik Domka2, Adrianna Malicka1
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Technology   Centre of Faculty of Chemistry, Adam Mickiewicz University of Poznan, Poland
Acrylic resins used in prosthetic dentistry are not free of faults, to which one can include poor
resistance to trauma and mechanical strain of the material. One of the laboratory methods aimed
at increasing the resistance of acrylic is the application of high - resistance synthetic fibers: glass,
carbon, polyethylene or aramid fibers. However, in cases of aramid fibers the problem of durable
bonding of fibers with acrylic resin continues to exist. The authors of this work have developed a
method of adhesion of resin to aramid fibers using many surface - active compounds. In the
study, aramid fibers Kevlar (DuPont) as well as auto-polymerized acrylic resin Villacryl
(Zhermapol) were used. In order to activate the surface of aramid fibers, treatment with
ultrasound waves was applied. Next, the fibers were covered with solutions of selected silane.
Kevlar fibers modified in this way were located in acrylic resin. Cross-sections of the samples
taken were submitted to observation in an electron microscope SEM. Microscope images were to
confirm the existence of a connecting silane layer between the aramid fibers and acrylic and their
proper adherence.

O58 - session: 10
ORAL
Coupled fields analysis /CFA/ of the Cr-Ni alloy-ceramics system
Janusz Juraszek1*, Rajmund Orlicki1,2, Grzegorz Wycisk2
1Higher   School of Dental Engineering, Ustron, Poland
2Department   of Stomatology and Biomaterials, Medical University of Silesia, Katowice, Poland
The increased interest in aesthetics and biocompatibility in prosthetics was caused by the search
for new materials used in fabrication of fixed restorations. Porcelain is commonly considered to
be the best aesthetic material for fixed prosthetic restorations. The aim of the work was to define
the influence of facing the Cr-Ni alloy with ceramics in increased temperature on the stress level
in the created ceramics-alloy system. The analysis of intensity of stress was performed basing on
the integrated MES ANSYS pack. A discrete model of the above problem was built. It enabled a
simultaneous process of thermal and structural analysis /CFA/. As a result of carried out
numerical simulations of the cooling process, the stress and strain patterns in the porcelain-metal
system were obtained. Comparative analysis of the selected sorts of porcelain and alloys
characterized by coefficients of thermal expansion were performed. The experimental verification
of the obtained computer simulations was performed by means of the diffraction method.

O59 - session: 10
ORAL
Structure of ceramics bonds
Maria Richert1,2*, Rajmund Orlicki2,3, Beata Leszczynska1
1Department of Non-Ferrous Metals, University of Science and Technology, Cracow, Poland
2HigherSchool of Dental Engineering, Ustron, Poland
3Department of Stomatology and Biomaterials, Medical University of Silesia, Katowice, Poland
The surface engineering is the most important in prosthetics. Especially the bond ceramics are
intensively investigated. The strength of bonds, their adhesives and thermal barrier coatings are
reported in numerous works. The improvements of coating technique include the broad
development of different investigations, especially connected with the bonds' structure. The
presented investigations concern Wiron and Remanium alloys, used now in prosthetics and the
new alloy Rodent, prepared by High School of Dentistry. Comparison of the quality of joints and
adhesion of porcelain to the investigated alloys was performed. The microhardness of alloys and
heating layers was measured. Using the optical, scanning and transmission electron microscopy
the detailed observations of microstructure were performed, with the investigations of chemical
compound in the investigation areas of samples. The investigations indicated transfer of metal
elements inside the ceramics and also some elements from ceramics into the metal matrix. The
new alloy Rodent showed very good properties, comparable with the presently used Wiron and
Remanium alloys. The bonds between all investigated alloys and ceramics did not show any
separation and other defects.

O60 - session: 10
ORAL
Sol - gel bioceramic materials for dentistry
Michal Posturzynski1*, Rajmund Orlicki1,2, Jozef Gluszek3, Bartlomiej Pawlus1
1Higher School of Dental Engineering, Ustron, Poland
2Department  of Stomatology and Biomaterials, Medical University of Silesia, Katowice, Poland
3Faculty of Chemistry, Wroclaw University of Technology, Poland
The article discusses the types of biomaterials used presently in dentistry with special
consideration being given to the research directed towards synthesis of new materials. From
among many methods of receiving ceramic biomaterials special attention was devoted to the
quickly developing sol-gel method. It has been proved that the sol-gel method can be a good
solution in the case of synthesis of very high purity materials with controlled structure composed
of sub-microscopic crystal grains. The method allowed obtaining inert monolotic ceramics in
relatively low temperatures from powders produced by means of this method as well as coatings.
The latter can have three types of application, namely as bioactive coatings on ceramic or
metallic implants, as coatings with a barrier character reducing the diffusion rate of metallic ions
from metallic foundation, and finally, as intermediate coatings between metallic substructure and
dental porcelain fused on it.

O61 - session: 11
ORAL
Long-term retentive forces of double crowns with additional attachment
Hans-Jurgen Wenz1*, Frank Emde2, Djamila Appelt1
1University   Hospital Schleswig-Holstein, Germany
2Memmingen,     Germany
Problems associated with unsatisfying retention are described in various studies investigating
different double crown systems. Using an additional attachment (TK-Snap, Si-tec, D-
Gevelsberg) was reported to be clinically successful. It was the aim of this study to investigate
long-term changes in retention of double crowns with clearance fit and an additional attachment.
Three different alloys CoCrMo/Wironit(CO), AuAgPt/MaingoldEH (AU) and Titanium/Biotan
(TI) were used to fabricate five double crowns in each group. Insertion/separation forces were
measured continuously using a contact-free inductive method. 10.000 insertion/separation cycles
were performed including artificial saliva in a new testing device. After completion of 10.000
cycles the wear of the titanium ball of the attachment (reduction of diameter) was measured and
the macroscopic surface changes of the inner crowns were evaluated. The double crown that
finished with the lowest retention value in each group was selected for attachment exchange and
subjected to another 10.000 cycles. A significant reduction in mean retention force was measured
for CO from 4.7N respectively for TI from 5.8N after 10 cycles to 1.5N/1.2N after 1000 and further
to 1.1N/0.6N after 10.000 cycles whereas the forces were nearly constant for AU (2.1N/10,
1.8N/1000 and 1.9N/10000). Wear of the titanium ball was highest for TI with 31.4% followed by
CO (24.3%) and AU (11.4%). The smallest surface changes of the inner crown were observed for
CO. After exchanging the attachment, the selected double crown in each group showed almost
identical retention values compared to the first 10.000 cycles with even slightly higher retention
forces at the end of testing. For all investigated alloys, part of the wear could be transferred into
the exchangeable attachment enabling a nearly complete reinstatement of retention which could
be demonstrated exemplarily. CoCrMo-double crowns presented the best combination of
predictable retention and surface resistance.

O62 - session: 11
ORAL
The wear of precision attachments under occlusal load - in vitro study
Szymon Rzatowski1*, Wieslaw Hedzelek1, Boguslaw Mroz2, Piotr Biskupski2
1Department    of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department    of Crystal Physics, Faculty of Physics, Adam Mickiewicz University of Poznan, Poland
The precision attachments provide superior retention and esthetics to the partial denture. The
variance of distribution of occlusal forces to the supporting structures may accelerate an atrophy
of alveolar ridge and be hazardous to periodontal status of abutment teeth. Besides the change of
retention force due to repeated placement and removal of the denture, daily activities such as
chewing, swallowing and other occlusal contacts with opposing teeth may also cause the wear of
attachments. The purpose of this experimental study was to evaluate the fatigue characteristics of
2 precision attachment designs under cantilever test. A total of 14 specimens were made, seven
ones included an attachment with slide, the rest with ball as male element. Both types of
attachments included a shear distributor. Two components of each sample were placed parallel
to each other to obtain complete seating of male part of attachment and predictable force
distribution. The silicone matrices with regular friction were pressed into Co-Cr matrix housings.
Each sample was subjected to repeated cycles of cantilever test in the testing machine (Dynamic
Mechanical Analyser -DMA 242, Netzsch). The force of 8N was applied to the female part of
attachment to simulate occlusal load. The storage modulus and amplitude of each sample were
recorded. The results indicated a significant difference between attachment types with respect to
the variance of amplitude of movable part of sample. Also the resistance to cyclic fatigue changed
in time in both groups. Within the limits of this investigation, it can be concluded that wear of
attachments under occlusal load depends on the type of attachment. Further investigations of
biomechanical aspects of wear of precision attachments are needed.

O63 - session: 11
ORAL
Mathematical modeling of stress distribution in a lower jaw with a partial removable
denture
Sonia Bartakova1*, Z Florian2, J Suchanek2, Jiri Vanek1
1Department      of Stomatology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
2Institute   of Solid Mechanics, Faculty of Mechanical Engineering, University of Technology, Brno, Czech Republic
In recent dental prosthetics, mathematical simulation can be used for the evaluation of stress
distribution in a jaw with different teeth numbers and shapes, as well as for various masticatory
forces. In heavily edentulous jaw, mathematical simulation can be used for the prediction of the
stress imposed on the clasps, retainers, and the sites of contact of a denture and the adjacent
teeth or tissue. In this contribution, we present results of mathematical modeling of stress
distribution in a lower jaw that was fitted with a partial removable denture. For the simulation, we
used finite element method and the ANSYS software. A 3-dimensional geometrical model of a
lower jaw was constructed. As an abutment, the first premolar was chosen and modeled as a 3-
dimensional object inserted in the respective location in the lower jaw. For simulation, the forces
typical for removable denture were chosen. In such a case, typical for treatment of heavily
shortened dental arch, the clasps of a denture are attached at the first premolar at either the
suprabulge or the infrabulge region. The simulation showed that maximum stress (?red) was
found around the abutment tooth on the vestibular side of a jaw. The maximum ?red values
depended on the site of clasps: in infrabulge region, ?red reached 13.7 MPa, while in suprabulge
region it was 18.8 MPa. The finding that the maximum ?red value was found in bone tissue on the
vestibular side of an abutment corresponds well with the evidence from clinical prosthodontic
practice. The above-specified bone region is frequently reported as the site of greatest bone
resorption. This implies that the mathematical modeling of stress distribution in a jaw with a
denture may provide a valuable assistance in the explanation of the bone resorption in this
particular bone region. Generally, mathematical modeling may provide a powerful tool for the
assessment of the response of a jaw to stress imposed by dentures before therapy is
commenced. This is of great importance, particularly in extensive and rare dental defects.

O64 - session: 11
ORAL
Tribological studies of dental materials used in prosthetic reconstructions
Anna Ryniewicz1, Andrzej Gala1*, Wojciech Ryniewicz1, Tomasz Madej2
1Institute   of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
2University    of Science and Technology, Cracow, Poland
Inlays made by indirect technique are a new, esthetic solution compared to amalgam fillings.
Such adhesive reconstructions have to be resistant to wear caused by occlusal loads. The aim of
this study was a tribological estimation of dental materials used to manufacture inlays made by
laboratory technique. Ceramic and composite materials have been chosen to perform present
studies. Samples were made according to manufacturer's directions. The control group consisted
of amalgam samples. The wear resistance was evaluated on tribologic machine Roxana Machine
Works in the environment of artificial saliva. Occlusal loads of molars were applied. The wear
resistance was measured by the amount of wear defects. Surface microgeometry of samples was
also studied. The highest wear resistance was observed in the group of ceramic materials.

O65 - session: 11
ORAL
Electropolishing of cobalt-based dental alloys
Malgorzata Ponto
Department of Preventive Dentistry, Medical University of Warsaw, Poland
Electrochemical polishing of alloys is the final stage of laboratory procedures aiming at
manufacturing of certain prosthetic restorations. Proper finishing of prepared metal surface aims
at reducing both the deposition of plaque on dentures and accumulation of food residues. That, in
turn, favors the longevity of restorations and a better condition of abutment teeth. This study
compared roughness and thickness of cobalt-chromium-molybdenum alloys after electropolishing
procedure. It also defined optimal parameters of electropolishing. Three groups of 27 rectangular
wax patterns (each 63 mm in length, 10 mm in width and 1.5 mm in depth) were prepared. The
wax patterns were cast under the pressure of 4.5 atm of argon. The cast specimens were
electropolished in nine groups, in 25oC, 40oC, 60o C in three different electrolytes. The cast
specimen surfaces were inspected under a microscope before and after electropolishing. The
surface roughness of each specimen was measured with profilometer (Alpha Step 200).
Profilometer and microscope examinations showed that the best results of electropolishing were
attained in 40oC, in the electrolyte of the following volume concentrations: sulphuric acid 8.7%,
ethylene glycol 90.9%, distilled water 0.4%. Surface roughness and loss of cast weight depended
on the electrolyte contents and temperature.

O66 - session: 12
ORAL
Tooth and soft tissue preparation for achieving esthetic results in fixed prosthodontics
Daniel Ziskind
Hadassah-Hebrew University of Jerusalem, Israel
Many factors might influence the end result in fixed prosthodontics. Anterior tooth preparation
presents a special challenge concerning the crucial impact on the patient's smile. In the esthetic
rehabilitation, we spare no effort using the best materials and laboratory techniques. In the
anterior region patient's satisfaction is a very important matter and presents an additional
dimension. Considering the soft tissue, understanding its anatomic characteristics and utilizing
special techniques present the quantum leap in creating the "invisible crown". In this lecture, the
rules of anterior tooth preparation will be presented and the rationale behind the process in
achieving an esthetic outcome will be discussed.

O67 - session: 12
ORAL
Aesthetic correction of anterior teeth in periodontally compromised dentition
Dagmar Vahalova
Department of Dentistry, Faculty of Medicine in Hradec Kralové, Charles University, Prague, Czech Republic
The authors describe a perioprosthetic treatment of a 37- year old female patient, who had been
treated at the Department of Periodontology since 2003. Decision to extract both periodontally
untreatable protruding and overerupting upper lateral incisors was made. It was necessary to
treat prosthetically the upper anterior dental arch segment. During detailed examination of
patient's dentition, the authors found out that there was an old unsatisfactory labially perforated
all-resin crown with visible dark-coloured dentin cervically and malocclusion in the sense of
inverted relationship between upper and lower left canines, what impaired aesthetics.
Furthermore, the teeth neighboring the lower left labially erupted canine were predictably inclined
into the free space making it narrower for the correct mesiodistal width of this tooth. Occlusion
examination showed a canine protected occlusion in, fortunately with low canine rise. The
provisional all-resin bridge replacing the lost upper lateral incisors was manufactured by indirect
immediate technique in cooperation with the laboratory. It was temporarily cemented immediately
after extractions. One week after lateral incisors' extraction we started to form the appropriate
mucosal surface shape of both provisional pontics by adding of LC-composite material to their
mucosal surface, which formed the desired seat for the pontic of the final PFM bridge. This
procedure has been repeated several times until the mucosal pontic seats were sufficiently
formed. Both left canines were endodontically treated and the inverted relationship was tried-on
by means of adapted slightly shortened provisional crowns . The labial inclination of the lower left
canine was solved by angled post and core and slight grinding of the lower lateral canine and
lower first premolar. The inverted canine relationship was satisfactory from aesthetic aspect and
the shortened provisional crowns proved that it was possible to convert the canine protected
occlusion to the bilateral group function. This occlusion type change was only possible after a
thorough analysis of casts mounted on articulator and after diagnostic wax-up of all aesthetic and
functional changes planned in the future.
O68 - session: 12
ORAL
Examination of the colour durability of selected prosthetic materials
Kamila Linkowska-Swidzinska1*, Ryszard Koczorowski1, Teodor Swidzinski2
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department   of Phoniatry and Audiology, Poznan University of Medical Sciences, Poland
Prosthodontic materials used for temporary crowns show a varied tendency to discoloration and
often cause patients to suffer serious esthetic discomfort. The aim of this study was to objectively
evaluate the colour durability of materials placed in various environmental conditions dependent
on the patient's diet. The study examined the following materials used for temporary fixed
dentures: a) Luxatemp (DMG), b) Structur 2 SC (Voco), c) Protemp II (ESPE), d) Zhermacryl
STC (Zhermapol), e) Dentalon Plus (Heraeus Kulzer). The previously prepared samples of
materials were exposed to the influence of experimental solutions of tea, coffee and juice from
dark fruits over different time periods. The colour characteristics of these materials were
evaluated using a light spectrophotometer (Specol-Carl Zeiss) with a special fiber-optic device
designed for photometric measurements. The monochromatic coefficients of light reflecting from
the samples were directly measured. It allowed calculating the colour coordinates in a CIE Lab
colour space. The samples placed in distilled water were established as the trial group.
Calculations were performed for two kinds of illuminations: daylight (D65) and artificial light (A) for
standard CIE 31 observer. The tested materials exhibited different liability to discoloration by
various experimental liquids. Structur 2 proved the most susceptible to discoloration whereas
Zhermacryl STC was the least susceptible. Changes in Lab parameters for one measured
material at three time ranges are shown in the table. The strong tea solution was the greatest
discoloration factor of all the testing liquids which affected all the materials in the physiological pH
range of the oral cavity. The use of certain materials for temporary fixed dentures necessitates
applying a diet that does not cause discoloration.

O69 - session: 12
ORAL
Processing of surface layer of cromium-cobalt alloy and its application in dental
implantology
Sonia Bartakova*, P Prachar, V Brezina, Jiri Vanek
Department of Stomatology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
Technically pure titanium or its alloys are frequently used in recent dental implantology. In spite of
optimal biological features, it is hardy processable. The aim of our study was to create a basic
material that would be processable. We used chromium - cobalt alloy as a basic material. This
material was processed so that the optimal biological characteristics could be reached. The
surface layer was coated with titanium nitride and zirconium nitride. Biological characteristics of
the resulting coated material were tested using a cell growth test with HeLa cells and MEM
cultivation medium with 10% CS added. Mechanic and physical properties of coated material
were investigated and compared to basic material. Results of biological testing provided growth
curves of number of cells. There were no reduction in number of cells with the time of cultivation
in coated material compared to control. Since no growth depression in number of cells was
apparent, it was concluded that the tested material was promising for dental implantology.
However, additional tests should be conducted for the final approval of biocompatibility.
Preliminary results presented in this study indicate high potential of chromium-cobalt alloys
coated with titanium nitride and zirconium nitride in recent dental implantology.

O70 - session: 12
ORAL
Multidisciplinary treatment of a woman with Papillon-Lefevre Syndrome - case study
Aneta Wieczorek*, Witold Jurczynski, Laura Czyzewska-Anyszek
Institute of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
Papillon-Lefevre is a genetic disorder, an autosomal recessive disorder of keratinisation, which
belongs to ectodermal dysplasia. It is characterized by the development of dry scaly patches on
the skins of the palms and the soles, the knees and the elbows and of the osteolisis of the bone
within the dental structure, the result of which is loosening and initially complete falling out of the
deciduous teeth, without resorption of their roots, and then complete shedding of permanent
teeth, as early as at the age of 16. The period of remission of pathological symptoms in the oral
cavity takes place after the complete loss of the deciduous teeth, which ends together with the
eruption of permanent teeth. This paper describes a multidisciplinary treatment of a 24-year-old
woman who underwent treatment in the University Dental Clinic. The radiological examination
showed a considerable horizontal atrophy of both the lower and upper jaws (periodontitis
simplex) as well as local periodontitis. Periodontological treatment was used in the first phase.
Then, in order to obtain an optimal occlusion the patient was treated orthodontically, using the
upper Schwarz's plate and permanent apparatus in the inferior arch. Afterwards prosthetic
treatment was applied. After the occlusive surface had been corrected, porcelain fused to metal
bridges on compressed crowns in a stepline pattern were made. The missing teeth in the
superior arch were rebuilt with frame prosthesis. The period of observation was 10 months.
Presently, the periodontal condition is satisfactory.

P001
POSTER
Interactive Structured Dental Cross
Zuzana Teuberova1*, Josef Spidlen2, Martin Pies2, Miroslav Nagy2, Tatjana Dostalova1,3, Petr
Hanzlicek2, Jana
Zvarova2
1Department of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
        of Computer Science, Academy of Sciences of the Czech Republic, Prague, Czech Republic
2Institute
3DMD, Prague, Czech Republic
Information storage in health care is basically in the form of written documentation.
Structuralization of information on prosthodontics and implantology is frequently done in the form
of a free written text, what is even stressed in the commercial software versions. Creation of the
Interactive Structured Dental Cross is as an advanced form of health documentation that will lead
to an easier and more complex treatment plan based on a greater amount of relevant information,
which is concentrated transparently. In the field of dentistry, not only a way of data
structuralization is important but also a form of transparent graphic presentation and editing.
Department of Dentistry of the First Faculty of Medicine of Charles University in Prague and the
Medical Informatics Department of the Institute of Computer Science, Academy of Sciences CR
developed software tools that dispose of interfaces enabling to connect graphic and high
advanced functional components. The 2D graphic components were developed in the form of
assigning external programmer's services for the purpose of securing relevance, complexity,
utilizability and user friendliness from the point of view of the dental specialist public. Knowledge
modeling by the dental knowledge base was created in a way that it should reflect needs of
prosthodontic and implantology documentation with the stress on dentistry. The data structure in
the dental cross are mapped using standard tools for data modeling. Detailed components of the
graphical dental cross can be utilized not only in a clinical practice but also in the field of research
and scientific works, where the advantage of data structuralization and their repeated deletion
according to required criteria is multiplied.

P002
POSTER
Dentures and other health features of mouth and body with eldery people
Marcin de Mezer1*, Jolanta Twardowska-Rajewska2
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department   of Adult Education, Faculty of Educational Studies, Adam Mickiewicz University of Poznan, Poland
The condition of dentition in the elderly isn't only an esthetic problem. All disorders of
stomatognathic system can generate malnutrition and in consequence worsening of health and
quality of life of seniors. The understanding of the role of geriatric dentistry in complex seniors'
therapy is insufficient among first contact physicians, as well as specialists. The aim of the study
was to evaluate the condition oral cavities of seniors (especially used dentures). The data were
collected from 23 patients of geriatric surgery, in the ages over 55 years, who were divided into 3
age groups. Examination was based on: A questionnaire (about dentures, tooth loosening,
hygiene and more), A dental examination A physical examination A complex gerontological
evaluation (MNA, MMSE, GDS, ADL, IADL) Small differences were noted between groups in
times of their first tooth loss and the length of time they wore dentures. Better oral hygiene
corresponded with increase in age. No correlation was observed between age and digestive
system disorders, but metabolic disorders were more common in patients over 75 years. Results
suggest, that patients who came to geriatric dispensary belonged to a group which was highly
educated and presented with the best general condition.

P003
POSTER
Oral health status in Helicobacter pylori infected peptic ulcer patients
Dorota Namiot1*, Maria Golebiewska1, Zbigniew Namiot2, Andrzej Kemona3
1Department of Prosthetic Dentistry, Medical University of Bialystok, Poland
2Department of Physiology, Medical University of Bialystok, Poland
3Department of Pathomorphology, Medical University of Bialystok, Poland
In the pathogenesis of peptic ulcer disease a crucial role is played by infection with H. pylori.
However, the lifetime risk of peptic ulcer in infected population ranges only from 5% to 25%. That
means that several extra factors are implicated in its pathogenesis. The aim of the study was to
ascertain, whether there is a difference in oral health status in H. pylori infected population
between peptic ulcer patients and healthy individuals. The subjects of the study were 105 peptic
ulcer patients (mean age 50 years; 65 men, 40 women) with ulcer niche located in the stomach or
duodenal bulb and 105 age and gender matched controls. Patients with peptic ulcers that could
have developed after treatment with non-steroidal anti-inflammatory drugs were excluded from
the study. The infections with H. pylori were determined in endoscopically taken slices from the
gastric mucosa by urease test (CLO-test) and histology. The mean number of natural teeth, filled
teeth and treatment index was lower, while the caries index, debris index, calculus index, and
periodontal index was higher in peptic ulcer patients as compared to healthy controls. Poor oral
health status might be one of the predisposing factors for the development of peptic ulcers in H.
pylori infected population.

P004
POSTER
Development of the human mandible in the early embrionic period
Marzena Wyganowska-Swiatkowska
Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
The mandible derives from the 1st pharyngeal arch ectomesenchyme and its development is
closely connected to Meckel's cartilage, mandibular division of trigeminal nerve and muscles of
mastication. The aim of this study was to investigate the relationships of these components in
embryos at stage 16, 17, 18. Ten human embryos aged between 37-44 days were examined. All
embryos were embedded in toto in paraplast and serially sectioned in three planes. Histological
sections were stained according to various methods. At the 16th stage the rod shaped Meckel's
cartilage is a very delicate structure supporting mandibular process. The Meckel's cartilage
followed the general curvature of mandibular process from the otic capsule to the future syphilis
where it corresponded with similar cartilage. Near its ventral end the mesenchymal condensation
(primordium of maleus and incus) and stylohyoideus muscle and styloglossus muscle were
visible. Mylohyoideus muscle was visible on the medial side of the cartilage. On the lateral
side of Meckel's cartilage followed the inferior alveolar nerve, which divided into terminal
branches: mental nerve and incisal nerve. Immediately below the inferior alveolar nerve the
concentration of mesenchyme and small arteries was observed. At the 17th stage, the primary
mandibular center of ossification developed in that place. Genioglossus muscle and
geniohyoideus muscle also developed. These muscles established their temporary attachment to
the Meckel's cartilage in embryos at stage 18. At that stage, from the initial ossification the
ramifying trabecular bone developed forward, backward and upward forming the trunk of
mandible. The intramembranous bone laid on the lateral and lower part of Meckel's cartilage. The
primordium of mandible appears on the 37th day post conception and the primary ossification
center develops intramembranously on the 41st day. The mandible develops independently of
Meckel's cartilage, on its lateral side, near the inferior alveolar nerve.
P005
POSTER
Prosthetic treatment needs in patients with non-controlled diabetes
Ewa Preferansow1*, Maria Golebiewska1, Ewa Kulikowska-Bielaczyc1, Maria Gorska2
1Department   of Prosthetic Dentistry, Medical University of Bialystok, Poland
2Department   of Internal Medicine, Medical University of Bialystok, Poland
Uncontrolled diabetes leads to the morphological changes in many organs. Presumably, the
stomatognathic system may also be influenced by the course of diabetes. The aim of the study
was to assess the dental defects and prosthetic treatment needs in patients with uncontrolled
diabetes (HbA1C > 7 %) as compared to a group of healthy people. Both groups were divided
according to gender. The study was carried out in a group of 275 patients. 155 of them were the
subjects with uncontrolled diabetes (test group), 120 were healthy individuals (control group).
Dental defects were assessed according to the Eichner`s prosthetic classification. In the group
with uncontrolled diabetes there were no people with full natural dentition (Eichner`s A1 class),
while in the control group the percentage of such patients was 15,8 %. 28,4 % patients from the
test group and 12,5 % of patients from the control group were edentulous. The prosthetic
treatment needs were greater in the group with uncontrolled diabetes, especially type II, and
concerned mainly treatment of the mandibular dental defects by the means of removable partial
and complete dentures.

P006
POSTER
Interdysciplinary treatment of patients with lip and alveolus cleft
Teresa Sierpinska1*, Maria Golebiewska1, Jan Borys2, Beata Bugala-Musiatowicz3, Leszek
Piotrowski2, Stefan Rybak4
, Stanislawa Z. Grabowska2
1Department of Prosthetic Dentistry, Medical University of Bialystok, Poland
2Department of Maxillofacial Surgery, Medical University of Bialystok, Poland
3Department of Orthodontics, Medical University of Bialystok, Poland
4???, Medical University of Bialystok, Poland
Successful prosthetic treatment of patients suffering from clefts is dependent on the close
cooperation between different specialists. It is a long-lasting and difficult treatment as it requires
taking into account long-term consequences of the therapy. Moreover, the developmental defect
in the nature of cleft, which is subsequently connected with the deformation of the face may affect
the psychological state of the patient. The final stage of long-standing therapeutic procedure is
the prosthetic treatment. Its aim is to improve functional and aesthetic conditions. This paper
presents three cases of young people who were treated at the Department of Prosthetics of the
Medical University in Bialystok due to the necessity to complete tooth and prosthetic basement
defects. The selection of particular prosthetic interventions was based on the cooperation with a
dental surgeon and orthodontist who had carried out pre-prosthetic preparations which made it
possible to achieve the satisfactory aesthetic effect.

P007
POSTER
The examination of oral health status in patients with hypertension
Katarzyna Taraszkiewicz-Sulik*, Anna Golebiewska, Maria Golebiewska, Arkadiusz Lewkowski
Department of Prosthetic Dentistry, Medical University of Bialystok, Poland
Complications of vascular system diseases are the most frequent reasons of death. These
illnesses are very often caused by hypertension of the blood pressure. The aim of our study was
to examine the conditions of stomatognathic systems and use of dentures in patients with
hypertension. The authors also wanted to find out the real prosthetic needs of these patients.
Patients with hypertension in the ages between 50-90 years were examined. The dentist in
attendance examined every patient The subjects were asked to respond to a special
questionnaire. Blood examinations were also performed. It was discovered that over 50 % of the
studied patients needed dental treatments and over 80 % needed to change their dentures. The
conditions of the stomatognathic systems in patients with hypertension were very poor. Most
patients required prosthodontic treatment.

P008
POSTER
Occurrence of periodontopathy among coronary patients
Beata Wisniewska-Spychala1*, Marek Jemielity2, Bartlomiej Perek2, Tomasz Maksymiuk3,
Jerzy Sokalski1
1Department of Dental Surgery, Poznan University of Medical Sciences, Poland
2Department of Cardiosurgery, Poznan University of Medical Sciences, Poland
3Department of Public Health, Poznan University of Medical Sciences, Poland
Inflammatory states of periodontal tissues constitute, beside caries, one of the two most
frequently occurring pathological processes in oral cavity. Their association with a host of
systematic diseases is well known. The objective of the study was to analyze the occurrence of
periodontopathy among patients with ischemic heart disease. The studied group comprised of
107 patients, qualified for a bypass procedure in one of the City hospitals. Both the frequency of
periodontal lesions and the depth of periodontal pockets were established during the
examination. Carefully selected diagnostic techniques were applied, in accordance with CPITN
and NHAMES III criteria. The earlier anticipated high frequency of periodontal lesions among
coronary patients was confirmed, principally in the 50 - 72-year age group. The frequency of
periodontal lesions among patients with coronary heart disease constituted a common problem in
that group.

P009
POSTER
Dental therapy patients after organ transplantation: extraction versus conservative
treatment
Ewa Jankowska-Antczak1*, Andrzej Wojtowicz2, Magdalena Golecka3, Wojciech Roszkowski1
1MedicalUniversity of Warsaw, Poland
2Department of Dental Surgery, Medical University of Warsaw, Poland
3Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
Dental care in patients after organ transplantation is discussed. The influence of dental treatment
on function of transplanted organ poses a difficult issue in treatment planning. Chronic
immunosuppressive therapy is necessary to protect transplanted organ, but it changes host's
response to inflammatory factors, including dental-derived infection. The aim of this study was to
estimate the reason for extraction and frequency of occurrence of chronic periapical inflammation
lesions in patients after organ transplantation, as well as to investigate activity of periapical
inflammation process in microscopy. 90 patients after organ transplantation, treated in
Department of Oral Surgery, Medical University of Warsaw were examined. The reasons for
extraction and frequency of occurrence of periapical granulomas were estimated. The tissue
samples of the periapical granulomas taken after extraction from 15 patients with
immunosuppression and 15 from patients without immunosuppression were also investigated. In
the microscopic picture of periapical granulomas the structure and cellularity, as well as collagen
network organization were estimated using hematoxylin and eosin and Syrius Red staining. The
incidence of periapical granuloma in patients with immunosuppressive therapy was more frequent
in carious teeth in comparisons with canal treated teeth. The evaluation of the microscopic picture
showed the difference of structure, cellularity and collagen network organization in patients
with immunosuppressive therapy in comparison with patients without immunosuppressive
therapy. Prevalence of fibrous elements and poor in cells inflammatory infiltration in organ
transplant recipients was estimated. The progression of chronic lesions in patients with
immunosuppression was estimated. Activity of periapical inflammatory process could be lower.
Elimination of inflammatory lesion from oral cavity after organ transplantation is necessary, but
the question is if the extraction of tooth with small periapical lesion is essential or can be replaced
with conservative methods of treatment e.g. apitectomy?

P010
POSTER
Some aspects of prosthetic rehabilitation of diabetic patients with osteoporosis
Zbigniew Kucharski*, Krystyna Rusiniak-Kubik, Elzbieta Mierzwinska-Nastalska
Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
Patients with osteoporosis often exhibit rapid continuing jawbone resorption, even under well-
fitted dental prostheses. Diabetes may increase the prevalence of oral infections and denture
stomatitis, thus posing problems with functional prosthetic rehabilitation. The aim of this study
was to evaluate some aspects of prosthetic treatment in two groups of men with diabetes and
osteoporosis compared to age-matched healthy ones. Patients received prosthetic treatment,
and removable complete or partial dentures were made. The radiological, clinical and
questionnaires examinations of masticatory system were preformed. To reduce the prevalence of
oral infections in diabetic patients the preservation of supporting bone structure by soft elastic
denture liners was not indicated, but regular control visits were recommended. As compared to
the pretreatment status, the surveyed patients showed masked improvement of functional
deficiency of the masticatory system.

P011
POSTER
Prosthetic rehabilitation of a patient with cleidocranial dysostosis
Denis Vojvodic*, Domagoj Zabarovic
Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Cleidocranial dysostosis (CCD) is characterized by a triad: clavicular aplasia, delayed ossification
of the fontanelles and sutures of the vault of the skull and hereditary transmission. It concerns
both the teeth and the jaw and is characterized by supernumerary teeth, delayed resorption of
deciduous teeth and eruption of permanent teeth, tooth impaction and eventually follicular cysts.
Developmental deformities of the permanent dentition are of primary concern in the prosthetic
treatment of patients suffering from CCD. A patient 26 years of age with CCD was examined at
our Prosthetic Department. Previously, he was surgically treated. Deciduous teeth were
extracted, and corticotomy was performed in order to enable eruption of permanent teeth. Firstly,
temporary removable prostheses were made for evaluation of the patient's ability to adapt to the
newly determined vertical dimension of occlusion and to stimulate the eruption of permanent
teeth. The patient wore the temporary removable partial prostheses for one year. Because patient
was comfortable with the newly determined vertical dimension, it was decided that the final
restoration would be constructed accordingly. Unfortunately no eruption of embedded teeth was
obtained. Telescopic crowns, coping with intraradicular retention and Dalla Bona stud attachment,
as well as metal-base partial dentures were designed. They resulted in satisfactory function and
esthetics. Prosthetic treatment of the oral condition is very important, not only to restore function
and esthetics but also to resolve problems with appearance associated with this disease.

P012
POSTER
Treatment needs with mini-invasive prosthetic reconstructions in adolescents
Elzbieta Rutanska1, Halina Panek1, Anna Sobolewska2*, Barbara Bruziewicz-Miklaszewska1,
Aleksandra
Krasnicka-Sciborska3, Beata Panek4, Pawel Nawrot2
1Department of Prosthodontics, Wroclaw Medical University, Poland
2Department of Dental Materials, Wroclaw Medical University, Poland
3Department of Functional Disturbances of the Masticatory System, Wroclaw Medical University, Poland
4Department of Dentofacial Orthopedics and Orthodontics, Wroclaw Medical University, Poland
Clinical observations reveal frequent occurrence of disorders affecting anterior part of dental arch
and influencing the esthetic appearance of patients, as well as the proper functioning of their
stomatognathic system. The goal of the study was to evaluate the requirements for esthetic
dental treatment among secondary school students and higher education students. The subjects
of the study were 50 secondary school pupils and 50 students of the Faculty of Dentistry. Method
of the study consisted of dental examination with special regard to hereditary and inquired
disorders of hard dental tissues of anterior teeth, and moreover, the disturbances in number or
shape or position of anterior teeth on the alveolar ridge. Prevalence of inquired or hereditary
disturbances in natural dentition was found to be high in studied adolescents. Such disturbances
as hypodontia, microdontia, enamelo-dentinopathies and some forms of tooth discoloration were
more frequent in female than in male subjects. The disturbances were frequently located in the
anterior part of dental arch. Frequent occurrence of genetic and acquired disturbances in natural
dentition was observed among the examined populations, which creates a great demand for
dental treatment with application of mini-invasive prosthetic reconstructions such as veneers.

P013
POSTER
Implantation procedure after sandwich bone augmentation of the atrophic mandible -
clinical report
Ewa Gawor1*, Barbara Ciechowicz1, Eugeniusz Spiechowicz1, Janusz Piekarczyk2, Danuta
Samolczyk- Wanyura3
1Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Department of Orthodontics, Medical University of Warsaw, Poland
3Department of Maxillofacial Surgery, Medical University of Warsaw, Poland
This clinical report presents the implanto-prosthetic treatment of a patient with severe atrophy of
the mandible. Edentulous 62-year-old male with atrophic mandible had persistent problems with
retention and stability of his conventional lower denture. Panoramic radiographic examination
demonstrated severely resorbed alveolar ridge. In the first stage, a sandwich augmentation of
mandible was performed using autogenous iliac bone graft. 9 months later augmentation graft
was clinically and radiographically successful, so that implantation could be performed. In the
second stage, six dental implants TBR system were placed. Implants were loaded 6 months after
insertion. Porcelain fused removable bridge supported on screw retained abutments was
fabricated. No implant losses or failures occurred. Patient's assessment was of good aesthetics
and intraoral function. Mobility of the implant was subsequently measured over the next 6 years
using Periotest device.

P014
POSTER
Prosthetic treatment supported on implants in atypical anatomical structures - a case
report
Tomasz Feder1*, Ewa Adamczyk-Sosinska1, Jerzy Gladkowski1, Malgorzata Grzelak2, Elzbieta
Mierzwinska-Nastalska
1
1Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Medical University of Warsaw, Poland
Prosthetic treatment of edentulous patients with overdentures supported on implants guarantees
satisfaction and comfort to patients. In rare cases, problems caused by anatomical structures,
nerves or vascular bunches appear, usually though it is a problem of insufficient amount of bone
over the mandibular canal where the alveolar inferior nerve is situated. In the region of the first
premolar, mandibular canal divides into two unequal branches. The wider one runs towards the
mental foramen and the narrow one as the lengthening of mandibular canal runs towards the
medial line. Usually, the space in the frontal region of mandible, between the foramina mentale is
utilized. In small percent of population, in this region, the narrow branch of mandibular nerve
canal is very visible and the structure on x-ray image appears as the lengthening of the
mandibular canal in total width. The reported case presents an edentulous patient with above
mentioned anomalies, who received overdenture treatment. Two implants of Osteocare system
were placed in anterior region of the mandible. Intraosseous implants were in close neighborhood
of the mental nerve. Implants were connected by a bar giving retention and stabilization to an
overdenture supplied with three clasps. This report presents clinical procedures, problems and 3
years follow up treatment.

P015
POSTER
Retrospective Clinical Study of Frialit-2 and Frialit-Xive Implants
Yalcin Ciftci*, Figen Demirel, Senay Canay, Ferda Tasar, Celal Tumer, Oguz Can Kasapoglu
Faculty of Dentistry, Hacettepe University, Ankara, Turkey
The use of implants in the treatment of the edentulous patient is well established. The implants
may be used to provide fixed restorations or removable overdentures. In this study, long-term
survival and success of different implant-supported prostheses supported by Frialit-2 and Xive-
Frialit implants were evaluated. 231 patients were rehabilitated using implant-supported
prostheses. 563 implants were loaded. The mean follow-up period was 5 years. Life table
analyses were performed. The cumulative implant survival rates were calculated for cantilever
fixed partial prostheses, fixed partial prostheses and overdentures. Implant success rates were
documented for implants placed in maxillae and mandibles. 19 of the 563 placed implants were
lost. The overall success rate was 96.63%. The results obtained in this retrospective study
population revealed an acceptable survival rate for these implant supported restorations.

P016
POSTER
Interdisciplinary treatment of hypodontia - case reports
Jacek Kukula1, Barbara Biedziak2, Edyta Solkiewicz1*, Mateusz Kurzawski2, Jerzy Sokalski1
1Department   of Dental Surgery, Poznan University of Medical Sciences, Poland
2Department   of Orthodontics, Poznan University of Medical Sciences, Poland
Congenitally missing dental germs belong to frequent tooth abnormalities. Most frequently this
concerns single tooth agenesis: the lower second premolars and upper lateral incisors.
Congenitally missing maxillary lateral incisor create an aesthetic problem, but also induce the
development of malocclusion. Unilaterally missing teeth additionally cause dental arch
asymmetry. The aim of this study work was to present results of interdisciplinary management of
congenitally missing maxillary lateral incisors with application of intraosseous dental implants.
Case 1: 20-year old patient with congenitally missing both upper lateral incisors treated because
of lateral cross bite on the right side. Orthodontic treatment with fixed appliance protocol was
planned to create the space for intraosseous implants. After sixteen months of treatment good
occlusion and proper bone conditions for Osteoplant implant (diameter 3.5 mm, length 12 mm)
application were obtained. Prosthetic ceramic crowns of both upper lateral incisors were made.
Case 2: 24-year old patient with absent maxillary left incisor and partial agenesis of the right one.
First phase of treatment dealt with orthodontic fixed appliance for proper teeth alignment in the
upper dental arch and space opening for intraosseous implant was gained. Osteoplant implant
(diameter 3.5 mm, length 12 mm) of missing upper lateral incisor was placed. Three months after
the implantation, prosthetic ceramic crowns of both lateral incisors were made. The
interdisciplinary orthodontic-surgical-prosthetic treatment of congenitally missing teeth enables
the reconstruction of normal occlusion and improves facial appearance.

P017
POSTER
The assessment of alveolar bone density arround the abutment teeth
Daniela Kovacevic*, Zoran Kovac, Robert Antonic, Natasa Blecic, Vlatka Mikic, Ivone Uhac
Department of Dental Prosthetics, School of Medicine, University of Rijeka, Croatia (Hrvatska)
Alveolar bone density changes during the life span. Abutment teeth and the bone around them
carry additional load from the lost teeth. The clasp transfers occlusal forces from them to
abutment teeth and their periodontal structures. These can load to increased and decreased
alveolar bone density depending on the direction of the forces. The aim of this study was to
assess the influence of situation of the antagonist teeth (present natural teeth or crowns,
antagonist as a part of dentures or cases of antagonist absence). The data were analyzed and
compared. 50 patients of both genders, carriers of PD were X-rayed twice in a period of 3 months
for standard retro alveolar radiograph. For calibration on each radiographs copper wedges of
different thickness (0,1-0,5mm) were used. The radiographs were digitized and the gray levels
translated into copper wedges' thickness equivalents on 7 regions of interest (ROI) according to
the Knezovic- Zlataric method. The same ROI were positioned around the abutment teeth on the
alveolar bone in both radiographs and the differences were analyzed by one-way variance test. In
the studied sample, in 40% of cases natural teeth or crown were present as an antagonist, 56%
antagonist was a part of the dentures and in 4% antagonist was absent. There was no statistical
difference in the alveolar bone density (p<0,05). The correct planning and axial direction of the
transferred forces on abutment teeth, periodontal ligament and alveolar bone did not disturb the
physiological balance of bone apposition and resorption, what resulted in the maintenance of the
alveolar bone density in the analyzed period regardless of the type of antagonist teeth.

P018
POSTER
Overdentures of the edentulous mandible supported on intraosseus implants
Ryszard Koczorowski1, Anna Surdacka2, Rafal Brozek3*
1Department    of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department    of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
3Ministry of Internal Affairs and Administration Hospital, Poznan, Poland
Rehabilitation of the patient with an edentulous mandible often fails to satisfy him due to problems
with retention and stability of the lower denture. The aim of this study was to provide the authors'
own opinion on the treatment of patients with edentulous mandibles using overdentures based on
implants and bar assemblies and to present selected cases. The paper presents selected cases
of prosthetic treatment of edentulous mandibles using overdentures with one, two, three and four
implants. The authors outlined their experiences of using various precision retention devices in
total overdentures that have been used predominantly in removable partial dentures. In order to
provide retention and stability attachment overdentures on bar assemblies were applied. Because
of the undesirable effect of changes in the direction of tensile forces in the bone that result from
biting forces affecting the tissue of the denture base, it is particularly important to properly place
and assemble implants and to adequately design precision retention elements while applying
overdentures. Clinical observation of the cases presented in the paper over a period of several
years and the patients' subjective impressions indicated that prosthetic treatment with
intraosseous implants was more satisfying and ensured more comfort for users of overdentures.
Regardless of the number of implants on which they were supported, overdentures are more
resistant to vertical and horizontal biting forces and provide a more effective treatment of
edentulous patients in comparison to conventional prostheses. 1.Using precision retention
elements allows the dentist to adjust the retention of total overdentures and to improve the
comfort of use. 2.The placing of retention elements in canine and premolar regions provides
better denture stability than their placement in the anterior region of the mandible. 3. A larger
number of implant abutments improves the retention and stability of mandibular overdentures

P019
POSTER
Immediate loading of implants with the use of overdentures - clinical procedure
Lukasz Lomzynski1*, Jerzy Gladkowski1, Ewa Adamczyk-Sosinska1, Piotr Okonski1, Elzbieta
Mierzwinska-Nastalska1,
Katarzyna Ciechowicz2, Dariusz Matenko2, Eugeniusz Spiechowicz1
1Department   of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Department   of Dental Surgery, Medical University of Warsaw, Poland
The complexity and protraction of the two-stage implantation procedure may discourage potential
patients even though it is the most documented and clinically tested method. High success ratio
of implant treatments along with the improvement of implants due to technological headway,
encourages the researchers to incorporate immediate loading of endosseous implants. Recent
studies show the possibility of constructing immediately loaded fixed suprastructures, but in the
following study the authors would like to present the methods and outcomes of performing
immediate loading procedures with the use of overdentures in patients with edentulous mandible
treated at the Department of Prosthodontics of the Medical University of Warsaw. Removable
dentures on implants may be planned and constructed in a larger group of patients with less
favourable bone foundation than the fixed restorations and are apparently cheaper then the latter,
which is of great importance to the majority of edentulous patients treated in our Department. All
cases were successful, with not one implant lost until the present moment.

P020
POSTER
Clinical and radiological evaluation of bridges connecting implants to natural teeth
Krzysztof Sidorowicz*, Jerzy Sokalski
Department of Dental Surgery, Poznan University of Medical Sciences, Poland
The permanent prosthesis can be made on natural teeth as well as on intraosseous implants.
Sometimes there is a clinical situation, in which connecting of those two abutments is required.
The aim of the study was to evaluate function and esthetics provided by bridges connecting
implants to natural teeth and to compare those results with function and esthetics achieved by
single crowns in similar clinical situation. The authors discussed advantages and disadvantages
of both solutions. In the study six cases were analyzed. Three of them were bridges which
connect implants to natural teeth, and three, in which a bridge connection was initially taken into
consideration, but eventually separate single crowns on implants and on root posts in natural
teeth were made. The status after three years of wearing was presented. Connecting implants to
natural teeth was an acceptable and very useful method of restoring missing teeth. One of its
advantages was improved stability. Other advantages included greater simplicity of the clinical
procedure and lower costs, which made them widely available to patients . Literature provides a
large discussion on the possibility of safe connections of implants and natural teeth.

P021
POSTER
The aesthetic aspect of prosthetic restorations based on implants in the anterior region of
maxilla
Jaroslaw Pospiech1, Wlodzimierz Lojewski2, Barbara Ziolecka3*
1Department of Dental Surgery, Poznan University of Medical Sciences, Poland
2Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
3Department of Paedodontics, Poznan University of Medical Sciences, Poland
Prosthetic restorations in the frontal part of the jaw are always a big challenge for a dentist. It is
especially difficult with those patients who have severe alveolar bone loss due to resorption after
the extractions or traumatic dental injuries. The change of bone shape is followed by soft tissue
deformation. In such cases the cooperation between the surgeon, periodontologist and the
specialist in prosthetic dentistry is strongly recommended. The aim of the paper was to present
implantological cases with prosthetic reconstruction in the frontal region of the maxilla. A clinical
and radiological examination of prosthetic reconstruction based on immediately inserted implants
or delayed implantation was performed. In both situations during implant surgery authors were
using the one-stage surgical protocol with healing screws. This implant methodology provides not
only stability for the implant but also a predictable long term soft tissue outcome. In the intra-oral
examination a very good soft tissue contour matching surrounding gingiva was noticed. In all
cases a proper alveolar bone height was visible on radiographs. The modification of one-stage
protocol described by authors, also with GTR technique provides in most of the cases a very
good aesthetic outcome. Patients are open and welcome the possibility to have all surgical
procedures completed during one visit.

P022
POSTER
Implant-prosthetic treatment after the sinuslift procedure
Ireneusz Machnikowski1*, Beata Borsuk-Nastaj2, Elzbieta Mierzwinska-Nastalska1
1Department    of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Medical   University of Warsaw, Poland
The sinus lift is one of the surgery procedures which is helpful in achieving the proper amount of
bone for an implant-prosthetic treatment. It is most important for patients, who plan to have
permanent prosthetic restorations. The study presents the planning and one of the methods of
surgery prosthetic treatment in selected clinical cases. Described patients were referred to the
authors with total and partial edentulous jaws. Special attention was paid to issues concerning
mutual relations of dental arch in occlusion and articulation. The treatment covered 18 patients
aged 45 to 72, who had the sinus lift done, before the implant treatment was performed. 22 sinus
lifts were performed and 74 Branemark implants were used. Plunged implants were used as
abutments for fixed restorations or as supports for removable prosthetic restorations. During this
study 20 crowns, 11 bridges and 4 overdenture prosthesis were made. A good functional and
esthetic effect was achieved. The clinical observations of treated patients lasted from 3 to 5
years.

P023
POSTER
Vascular endothelial growth factor (VEGF) in gingival crevicular fluid of patients with
periimplantitis
Elzbieta Mierzwinska-Nastalska1*, Piotr Okonski1, Ewa Adamczyk-Sosinska1, Jerzy
Gladkowski1, Lukasz Lomzynski1,
Urszula Demkow2
1Department   of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Department   of Immunology and Diagnostic Laboratory, Instytut Gruzlicy i Chorob Pluc, Warsaw, Poland
Angiogenesis occurs under physiological and pathological conditions and is regulated by the
cytokines and growth factors. Vascular endothelial growth factor (VEGF) is a multi-functional
angiogenic cytokine of importance to inflammation and immune responses, which are implicated
in the pathogenesis of inflammatory processes of the tissues surrounding the implant. The aim of
the present study was to investigate the concentrations of VEGF in gingival crevicular fluid (GCF)
in healthy and diseased soft tissues surrounding implants. In clinical examinations periodontal
status of soft tissues around dental implants was evaluated with the Florida Probe. Bone loss was
examined radiologically. Vascular endothelial growth factor concentrations were assessed using
immunoabsorbent assay - ELISA. Higher concentrations of VEGF were detected in crevicular
fluid with periimplantitis compared with clinically healthy sites. The concentrations of VEGF were
significantly correlated with pocket depth. The presence of vascular endothelial growth factor in
gingival crevicular fluid of patients with periimplantitis may be a factor in the progression of
periimplantitis, possibly by promoting the formation of new blood vessels in angiogenic
processes.

P024
POSTER
Effect of platelet-rich plasma on osseous healing after bilateral sinus-lift augmentation:
radiographic analysis
Petr Simunek1*, René Foltan1, Tatjana Dostalova1,2
1Department  of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
2DMD,   Prague, Czech Republic
Maxillary bone grafting procedures using sinus lift techniques are commonly used prior to implant
placement. The prosthetic stage of treatment is usually delayed due to lengthy osseous healing
process. Several studies report on the use of platelet-rich plasma and its potential to improve
osseous healing and stabilization of grafts. Five cases with bilateral maxillary defects are
presented in which platelet-rich plasma and allogenic material were used for the sinus lift
augmentation of both sides prior to implant placement. The mixture of PRP and bone substitute
was carefully pushed opposite to the medial wall of maxillary sinus on the one side, whereas the
opposite side was augmented with allogenic material without PRP. Radiographic evaluation was
performed 3 and 6 months after graft placement. The healing period was complication-free and
both sides indicated adequate consolidation of the grafting material. The appearance, density of
heterogeneous graft and rate of remodeling of beta-tricalcium phosphate on the side with PRP
was compared to the control side. Authors discuss methods of platelet-rich plasma preparation,
its advantages, limitations and possible effect on osseous healing.

P025
POSTER
Research into electoroformed implant overdenture (electro conductivity of primary
Zirconoxid bar)
Hayashi Shoji1*, Naoki Yamada2, Katuo Shibuya3, Heiner Weber4, Ekkehard Kroewerath4
        of Frontier Oral Science, Kanagawa Dental College, Yokohama Clinic, Japan
1Institute
2Kanagawa  Dental College, Yokohama Clinic, Japan
3Kanagawa Dental College, Yokosuka-shi, Japan
4Department of Prosthodontics, University of Tuebingen, Germany
Electroformed metals are known to present good adaptability and biocompatibility, but it is not yet
known if the retention force of the electroformed secondary bar frame (ESBF) can endure long
use. To clarify this point, the retention force between the primary Zirconoxid bar and ESBF was
measured. A model of edentulous jaw was prepared and four implants (Xive,Dentsply
Friadent,Germany) were embedded. The fabrication of the primary bar was manufactured from
Cerecon system (DegDent, Germany). The authors coated the completed Zirconoxid bar with
silver lacquer, applied electroless silver plating process and 0.3mm thick electro deposition (AGC
Micro, Wieland Dental + Tecnik). The ESBF was attached to the Zirconoxid primary bar, retention
force was performed for cycle test. The retention forces were measured in 37 degree distilled
water. The retention force value dropped as the number of reseatings increased both silver
lacquer and electroless silver plating. The retention force of using silver lacquer poorly compares
with the electroless silver plating. Hysteresis curve indicated that the resistance during cyclical
testing was constant and stable up until the completion of last cycle. The results confirmed that
the retention force dropped gradually as the number of cycles increased but the stress imposed
on the implants due to replacement and removal was low. This might be due to the excellent
adaptation accuracy. It was also found that the electroless silver plating process was particularly
effective for the manufacture of equipment that required superior matching accuracy, such as the
electroformed frames of implant overdentures and telescopic crown denture. Supported by
Wieland and DegDent GmbH.

P026
POSTER
Biological & mechanical properties of titanium implant covered with hydroxyapatite and
zirconia layers by
pulsed laser
Michaela Seydlova1*, Zuzana Teuberova2, Tatjana Dostalova2,3, Barbora Dvorankova4, Karel
Smetana4, Miroslav
Jelinek5, Tomas Kocourek5, Waldemar Mroz6
11st Faculty of Medicine, Charles University, Prague, Czech Republic
2Department    of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
3DMD, Prague, Czech Republic
4Institute of Anatomy, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
5Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
6Institute of Optoelectronics, Military University of Technology, Warsaw, Poland
It is suggested that specific biological responses of early-loaded implants are directly related to a
specific combination of the bone-implant interface, implant design and type of prosthetic
reconstruction. The purposes of implant coating are several, i.e., the enlargement of its surface,
protection of the metal nucleus against corrosion, and permanent isolation. At present, the most
preferable way of coating implants is a thin crystalline layer of hydroxyapatite (HA). The pulsed
laser deposition was introduced in 1992 due to high quality HA coating deposition. The aim of our
study was to clarify how the mechanical/physical properties of the implant influence its biological
behaviour. Sample of an implant was a target (titanium alloy Ti6Al4V with the HA coating and
ZrO2 interlayer) with a diameter of 10 mm and thickness of 2 mm. The depositions of
hydroxyapatite films were carried out in two different deposition set-ups, where KrF and ArF
excimer lasers were used. The film morphology was observed by scanning electron microscopy.
Coated samples were compared with positive and negative controls in a direct test of cytotoxicity
and than in tests of adhesion and proliferation. Two types of fibroblasts were used - 3T3 mice and
human dermal fibroblasts. Then fibronectin expression of these cells was proved. Analyses of the
target surface by XRD technique verified that HA on the surface was crystalline. We confirmed
that the studied material with the crystalline HA coating and the interlayer from zirconium was
not cytotoxic. Fibroblasts cultured for 72 hours expressed fibronectin in cytoplasm. Results
confirm that the titanium target with HA and zirconium is equally attractive for fibroblasts as the
tissue culture grade polystyrene. The pulsed laser deposition seems to be a promising method of
coating the thin layers of zirconium and HA.

P027
POSTER
Patient with a fixed partial denture made of ocean shell
Asja Celebic1*, Marko Guberina2, Maja Pavic1
1Department    of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
2School   of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Satisfaction with fixed partial dentures (FPD) has a multicausal character. Some factors related to
the patient are well documented: patient's personality, attitude and motivation. The aim of this
paper was to present a patient who was not satisfied with her 6 previous FPDs due to the
materials which were used to fabricate them. She had 6 FPDs made of different materials: Pd-Ag
+ acrylic, Au alloy + acrylic, Au-Pt + isosit, NiCr ceramics, targis-vectris, acrylic removable partial
denture with golden clasps. She objected that none of the materials were healthy (she considered
herself an expert in alternative medicine). She complained of headaches, progression of sight
impairment, dry and burning mouth, thirst, pain in medial corners of the eyes, loss of taste and
coughing. A hydrothermal ceramic (Ducera-gold) FPD was suggested. This new FPD did not
alleviate any of her complaints. The patient did not agree to permanently fix the denture. She also
asked if her new FPD could be made of ocean shell. When she received a negative answer from
the dental staff, she purchased all the necessary equipment used by technicians to fabricate
dentures. She also had a cast poured in hard stone. Five months later she was still busy drilling a
seashell and adjusting it to the cast. She inquired with the dental staff whether her "masterpiece"
could be permanently fixed in her mouth. After thorough consultation about the shell composition
and its potentially harmful effects, the decision was made to fix it temporarily. From the
professional standpoint the color of the restoration was not satisfactory, neither was the fit nor the
shape. The patient on the other hand was very satisfied and had no further complaints. She even
reported that her sight improved. She wore the temporarily fixed FPD for one year. During this
time the material became porous and eventually dissolved. She didn't want FPD made of any
other material than a seashell. The patient is currently "constructing" another FPD from a new
ocean shell. The question should be raised: "What if a patient like this comes into Your office?"

P028
POSTER
Precision attachments and overdentures in prosthodontic rehabilitation of patients
following malignant tumors
surgery
Dariusz Rolski*, Krystyna Rusiniak-Kubik, Elzbieta Mierzwinska-Nastalska
Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
Patients after surgical operations in the maxillofacial region (jaw partial resection or
hemimaxillectomy and hemimandibulectomy) often lack most features considered necessary to
support dentures. Encroachment of surrounding tissues onto the denture space, postoperative
defects and scar formation reduce denture stability and retention. Construction of the
overdentures supported on precision attachments placed on endodontically treated roots was
considered the best way to preserve residual teeth, ridges and provide retention and stability of
the dentures. In the postoperative patient group studied by the authors, precision attachments -
single root round attachments or bar constructions - significantly impacted the functioning of the
overdentures. Evaluation of abutment teeth, diagnosis, periodontal, endodontic and restorative
treatment, as well as the choice of the attachment type were the major concerns for
prosthodontists working with these patients. To achieve optimal distribution of functional load
between the impaired operated side, postoperative defects and to reduced prosthesis bearing
area emphasis was placed on the occlusion of the overdentures. For fabrication of the
overdenture prostheses in postoperative patients the use of high impact acrylic resin or cast
chrome-cobalt minibase or full denture base were recommended to reduce the risk of failure due
to fractures. Proper, cautious maintenance and adequate after-care of the patients were essential
factors to attain satisfactory functioning of the parts of precision attachments and overdentures.

P029
POSTER
Risk of Overdenture Procedure Failure
Michaela Seydlova1*, Zuzana Teuberova2, Tatjana Dostalova2,3, Prokop Radina2
11st   Faculty of Medicine, Charles University, Prague, Czech Republic
2Department  of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
3DMD,   Prague, Czech Republic
Overdenture treatment is one of the possible ways to treat patients suffering from periodontal
disease on condition that other teeth cannot be used for any other prosthetic purposes.
Overdenture´s torsion and overloading in function can lead to overdenture´s damage. Case
report: Our patient was a 47-year-old woman who had her overdenture infracted in
loco 14. This woman did not suffer from any allergies and was not treated for any diseases. In the
upper jaw there was an overdenture made from methylmetacrylate. The retention was supported
by three ball attachments (noble-precious alloy) in loci 14, 23, and 25 - Kennedy Class III/2. In the
lower jaw, there was the Kennedy Class I proving movement in the range from 1 to 2 mm of every
tooth. After detailed analysis of the study casts in the articulator, a deep bite and many articulacy
obstacles were detected. After careful analysis of the situation, we decided to prepare new
overdenture with a special metal reinforcement. Occlusion reconstruction including lower jaw
rehabilitation was planned. Initially, we made preliminary impression with alginates and later the
definitive impression with polyether in the individual tray. Selective grinding based on articulator
analysis was made; record blocks helped to reconstruct new lower jaw position. After selection of
artificial teeth, we proved the model of the overdenture. New overdenture with metal
einforcement was made from methylmetacrylate.

P030
POSTER
Conical crowns versus ball attachments - retained removable partial denture
Lukas Cupal1*, Tatjana Dostalova1,2
1Department  of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
2DMD,   Prague, Czech Republic
Patient with history of advanced caries and/or periodontal disease often has a few remaining
sometimes unfavorably distributed teeth in the arch. Those teeth have variable prognosis, namely
from a periodontal point of view. The indication for placing crowns with precise attachments or
conical crowns on abutment teeth is a difficult solution. Splinting of the remaining teeth, reliable
retention and stability eliminate the clasps. Advantages of fixed and removable denture from the
aesthetic point of view must be compared with abutments requiring extraction. The aim of the
study was to evaluate the advantages and disadvantages of both systems in a case report. The
patient was a 79 years old man, with glaucoma, hypertonic, prostate hypertrophies and a
Kennedy class I/1 dental status. In maxilla there was an 8 year old conical crown-retained
denture. There were copings on tooth 14 and tooth 25. The tooth 25 was overloaded;
movement and bone atrophy on x-ray was detected. The tooth 15 was extracted and new
treatment plan with sufficient retention and aesthetics was established. Fixed metal ceramics
bridge 15 - 22 with ball attachments on distal faces was prepared. Two spherical anchors
provided retention of removable denture. The study portrays the step by step process including
the plan of treatment and consideration of alternative solutions.

P031
POSTER
Partial and complete overdentures with magnetic attachments - clinical evaluation
Slawomir Makacewicz*, Honorata Krawczykowska, Halina Panek
Department of Prosthodontics, Wroclaw Medical University, Poland
Introduction of rare earth magnetic materials such as Sm-Co (Samarium-Cobalt) and Nd-Fe-B
(Neodymium-Iron-Boron) resulted in the production of magnets with small enough dimensions to
be used in dentistry for retaining removable dentures. The main problems associated with the use
of magnetic retentive devices is their corrosion in the oral environment. However, current magnet
assembles are encapsulated in stainless steel or titanium sealed using laser welding, like for
example a commercially available system Dyna (Dyna Dental Engineering, the Netherlands). The
aim of the study was to evaluate the clinical usefulness of Dyna magnet system for retaining
partial and complete overdentures. The Dyna attachments were used in a group of patients with
residual dentition in the mandible or in the maxilla, who were treated in The Department of
Prosthodontics in Wroclaw since 1995. During periodical examination, the clinical evaluation of
abutment teeth were performed, as well as radiological X-rays were made to assess the degree
of loss of alveolar ridge bone. Moreover, a visual inspection of Dyna capsules was made. On the
basis of almost 10-year clinical observations of overdentures retained with Dyna system the
authors stressed that the magnetic attachments revealed high technical quality without any
damage or need for their replacement. Moreover, the authors observed minimal harmful influence
of the magnet attachments on periodontium of the abutment teeth in comparison to the potential
for harm when using the conventional mechanical attachments for such long period of denture
wearing.

P032
POSTER
Achieving perfect esthetics with using the "Finesse - All-Ceramic" for crowns and veeners
- case
Julijana Nikolovska1*, Angele Ginovski2, Dejan Gacov2
1Faculty   of Dentistry, University of Skopje, Macedonia, The Former Yugoslav Republic
2Private   Dental Practice, Skopje, Macedonia, The Former Yugoslav Republic
The aim of this study was to present the authors' clinical experiences with "Finesse All-
ceramic"(CERAMKO, Dentsply,USA) as a material used during fabrication of all-ceramic crowns
and veneers to achieve better esthetics. In our everyday clinical practice we made about 50
"Finesse All-Ceramic" crowns and veneers in a period of two years. We used this material in the
anterior and the premolar region, in cases with normal occlusal relationships, without existing
periodontal disease and parafunctional behavior (e.g. bruxism) After cementation, our patients
were more satisfied with the esthetics of the new all-ceramic restorations than with the old metal-
ceramic crowns they had before. The new restorations were very light and they felt more
comfortable in the patients mouths. During patients' control visits, six months after the
cementations, we noticed that "Finesse All-Ceramic" as low-fusing porcelain system showed less
abrasion than high-fusing porcelain and it was significantly kinder to opposing dentition than
conventional porcelains. Exceptional chair side polishability makes .Finesse All-Ceramic.
restorations easier for everyone: the dentist, laboratory technician and the patient.

P033
POSTER
Case report: design and fabrication of an auricular prosthesis by stereo lithography
(optical scanning and
CAD-CAM)
Mustafa Kocacikli*, Suat Yalug, Huseyin Yazicioglu
Gazi University, Ankara, Turkey
There are several techniques in auricular prosthesis construction. A time consuming step in these
techniques is the modulation stage. In the presented case, auricular prosthesis is produced
through the stereo lithography technique (optical scanning and CAD-CAM) for a patient who lost
his right ear due to cancer. Successful aesthetics, minimal skills and little time lost are the
advantages of fabricating auricular prosthesis though this technique. Patient comfort is
guaranteed by short procedure time and best aesthetic results.

P034
POSTER
Application of Titanium Crown (CAD/CAM system) to Metallic Allergic Patients
Tomoji Sawada*, Tomofumi Sawada, Atushi Uryu, Mituru Okudera, Minoru Toyoda
Kanagawa Dental College, Yokosuka-shi, Japan
Recently, a lot of dental CAD/CAM systems that apply IT and the network technology are being
developed. The improvement of the accuracy of the prosthesis department mending device and
the improvement of the quality, such as stabilization of the form etc. are enumerated as an effect
of the introduction of the dental CAD/CAM technology. Moreover, attempts are being made to
improve the working environment and productivity. The achievement of a new dental treatment
form can be expected because of an increase in the variety of available materials. The purpose of
the research was to estimate possible the application from the attempt of a clinical of the
prosthesis produced with the dental CAD/CAM system application, and stability on the material to
a metallic allergic patient, and the effect be expected. The outline of this system and the
production procedure of the prosthesis were presented. And, this system reports on the example
of clinical application of the prosthesis that processes the titanium metal to the allergic patient. In
the actual experiment, pure titanium was processed using dental CAD/CAM system DECSY (
DIGITAL PROCESS LTD.) and the crown was produced. The feature of DECSY is the design
automation, an additional edit, and the prosthesis with the occlusal form is made by the automatic
operation. Measurement condition : Laser measurement (Decsy Scan) 4 min. Design :
automation 1 min. Milling : 4 axes 2ATC 60 min. Materials : Pure titanium (JIS Type2) With
this dental CAD/CAM system it was possible to fabricate the tooth restoration and the prosthesis
automatically by the occlusal form and simplification of previously used complex operation was
achievable. Milling one titanium crown would end in about 60 minutes at the time required for the
processing, and the agreement accuracy of the crown was excellent. The relapse of abnormality
and an allergic patient of the crown is not and passes, too, when the titanium crown was installed
in an allergic patient. The example of clinical that uses the ceramics material is scheduled to be
examined in the future.

P035
POSTER
All-ceramic adhesive bridges
Lucie Dickova*, Jana Krnoulova
Department of Dentistry, Faculty of Medicine in Plzen, Charles University, Prague, Czech Republic
The adhesive bridges (fixed partial dentures) are not only used as long-term provisional
restorations, but also as final prostheses for adult and juvenile patients. In standard practice,
these bridges are made by combining dental alloys and ceramics or resin. Our retrospective
study evaluated usage of Empress 2 system to fabricate adhesive bridges from the point of view
of mechanical qualities. The ceramic adhesive bridges combine the advantages of classic
construction (low invasive preparation) and the advantages of ceramics (good aesthetics and
biocompatibility). All ceramic adhesive bridges were created for: - juveniles and adults in cases of
aplasia or posttraumatic loss of a frontal tooth (in most cases it was in the upper jaw) - adults
after losing one premolar or molar 36 ceramic adhesive bridges (16 in frontal segment and 20 in
lateral segment) were made from all-ceramic system Empress 2 by Ivoclar Vivadent. The amount
of space available was a limiting factor for the use of ceramic adhesive bridges. All-ceramic
adhesive bridges represented a very good alternative compared to classic bridges or adhesive
dentures with metal framework. They were a good solution to treat small defects of frontal or
lateral dentition. The authors encountered only four failures - fractures in places of connection.
The poster presents several clinical cases where all-ceramic adhesive bridges were used.
impress 2 exhibits very good mechanical properties conducive for making this type of partial fixed
dentures and is characterized by excellent aesthetic design.

P036
POSTER
Sintering kinetics of a veneering ceramic for zirconia and titanium
Pawel Pazera*, Christof Kubata, Peter Riederer, Catherine Solioz, Jens Fischer
University of Berne, Switzerland
The introduction of new framework materials, such as ZrO2, requires new veneering ceramics
with appropriate characteristics. As the thermal expansion of ZrO2 and titanium are quite similar,
veneering ceramics were developed which suit both materials (e.g. Triceram, Dentaurum,
Pforzheim, Germany). Due to their lower melting temperature these ceramics are more sensible
in processing. Firing is especially a crucial step. The aim of this investigation was to determine
the kinetics of the sintering process of Triceram and to investigate if hardness measurement is
the appropriate method. Ceramic test pieces (Triceram dentine A3) with dimensions of 3mm x
25mm x 1.5mm (W x L x H) were sintered at different firing temperatures (Austromat D4,
Dekema, Freilassing, Germany) ranging from 600°C to 940°C, using a heating rate of 55K/min
according to the manufacturer's recommendations. The samples were embedded in acrylic
blocks, the surface was ground and polished and Martens and Vickers hardness were measured
10 times on each sample (ZHU 2.5, Zwick, Ulm, Germany). The structure of the samples and
typical indentations were documented by means of SEM. Martens hardness shows an increase
with increasing firing temperature. The sintering process starts at about 640°C and the maximum
hardness is reached at about 750°C, indicating that the sintering occurs in a narrow temperature
range of 130K. The Vickers method does not allow for measuring samples with a lower density,
because the indentation is not clearly visible. The sintering process of Triceram takes place in a
very narrow temperature range. The firing temperature given by the manufacturer represents the
sintering temperature at the heating rate of 55K/min and under this aspect is optimal. The
Martens hardness is a useful method to determine the sinter temperature of a ceramic.

P037
POSTER
Diametral and compressive strength properties of different core materials
Gulbin Saygili1, Yalcin Ciftci1, Bulem Yuzugullu2*, Senay Canay1
1Faculty   of Dentistry, Hacettepe University, Ankara, Turkey
2Faculty   of Dentistry, Baskent University, Ankara, Turkey
This study was undertaken to compare the mechanical properties of materials used for direct core
foundations. The differences between the compressive and diametral tensile strength of six core
materials including Amalgam (high-copper amalgam), Grandio (visible light-cured nanohybrid
resin composite), Admira (ormocer), Filtek P60 (packable composite resin), Rebilda DC (dual-
cure adhesive core material) and Argion Molar (silver reinforced glass ionomer cement), were
tested. A total of 72 specimens, half for the compressive test (n=6) (6mm in height and 4mm in
diameter) and the other half for the diameter compressive strength test (n=6) (6mm in diameter
and 2mm in height) were prepared. The specimens were stored at room temperature in distilled
water for 7 days. The Lloyd testing machine was used to load the specimens at a cross-head
speed 0,5cm/min. The strength values were determined in MPa. Kruskal Wallis test was
computed and multiple comparison tests discerned many differences between the materials
(p<0.05). Compressive strengths varied widely from 107.13 MPa for Argion Molar to 360.92 MPa
for Admira. Diametral tensile strength ranged widely from 9.06 MPa for Argion Molar to 54.71
MPa for Filtek P60 Packable composite resin (Filtek P60), visible light cured nanohybride resin
composite (Grandio) and Ormocer (Admira) had higher compressive and diametral tensile
strength values than the other materials.

P038
POSTER
Influence of Timing of coronal Preparation on Retention of Two Kinds of Post-Core
Systems
Gulbin Saygili*, Sevil Sahmali, Figen Demirel
Faculty of Dentistry, Hacettepe University, Ankara, Turkey
When much of the clinical crown has been destroyed and a post-core was made, post retention
and stability are crucial for the success of the final restoration. The nature and timing of forces
acting upon restoration are also important. Vibration generated by rotary instruments during
preparation may affect the post retention. The aim of this research was to study and compare the
effect of coronal preparation on retention of cemented cast ( Cr-Ni ) and IPS post-core systems.
Cr-Ni and IPS post and cores were fabricated for 48 extracted, single rooted, human teeth with
two different cements (dual cure and glass ionomer ) and randomly divided into 4 groups of 12
specimens each. Twelve of each post-core systems were cemented with dual cure cement and
the other twelve of each system were cemented with glass ionomer cement. Twelve specimens of
each post-core system were subjected to an axially directed removal force using a universal
testing machine. Four groups of 12 specimens were divided into two subgroups and were
subjected to preparation of their cores at 15 minutes and 24 hours after cementation .The
specimens were tested at 24 hours having been stored in water 37°C for the waiting period. The
forces required for dislodgement of posts from their prepared spaces were recorded. The data
were statistically analyzed using ANOVA-The Newman-Keuls Multiple Comparison test. The
results showed that retention generally increased with time following cementation for both groups.
The specimens cemented with glass ionomer cement revealed less retention compared with
specimens cemented with resin cement. Preparation of cemented post-cores using a high speed
hand piece had a significant negative effect on retention when carried out 15 minutes and 24
hours after cementation.

P039
POSTER
An alternative technique for a post and core restoration
Bahadir Ersu*, Senay Canay
Faculty of Dentistry, Hacettepe University, Ankara, Turkey
A post and core restoration is placed in a badly broken down tooth to restore the bulk of the
coronal portion of the tooth in such a way as to facilitate the subsequent restoration of the tooth
by means of an indirect extracoronal restoration. In this case report an alternative technique - an
intracoronal anchorage and an extracoronal restoration - for these weakened teeth was
described. A 25-year-old woman was referred to the clinic with the absence of first molar on the
mandibular right segment. After root canal treatment to the extensively damaged second right
mandibular molar tooth a special design core and a post extending to the distal root was cast.
After adjustment of the post and core assembly a precious attachment was soldered to the core
to provide retention for the three unit fixed prosthesis which will be fabricated between the second
premolar and molar teeth. The core and porcelain fused to metal three unit fixed prosthesis were
cemented to the teeth with resin cement. During cementation of the bridge, the ceka base ring
was screwed to the second molar tooth with the ITI fixture. This technique seems to be
convenient for the extensively damaged tooth especially to the ones, which have insufficient
space between arches to make a conventional post and core restorations.

P040
POSTER
The influence of selected factors on retentive strength of prefabricated posts
Magdalena Tanska1*, Malgorzata Marzec-Gawron1, Marcin Kubani2
1Medical   University of Warsaw, Poland
2Department    of Prosthetic Dentistry, Medical University of Warsaw, Poland
One of the guiding principles of contemporary dental prosthetics is the use of the remaining teeth.
The aim of prosthetic treatment is the restoration of masticatory efficiency comparable to that of
natural dentition. Restoration of a lost crown on canal-treated roots can be achieved using
manufactured or cast posts. The aim of the study was to assess the shear strength of selected
cements during pull-out testing of standard posts and to examine the effect of endomethasone
and eugenol on the post retention. The study was carried out on 25 roots of single-root teeth. The
roots were subdivided into 3 groups. Two groups received endodontic treatment with
endomethasone and eugenol. After 2 weeks, root canals in all groups were prepared with a 1.6
mm calibrated drill and posts were cemented in place with phosphate cement (Agatos)
and compomer cement (PermaCem). Within 72 h of cementing the posts were pulled out using
an Instron 1115 machine at the Institute of Mechanics and Construction, Warsaw University of
Technology. The following mean values of pull-out strength were obtained for the cements tested:
compomer cement: 193 N; phosphate cement + endomethasone in the root canal: 131 N;
compomer cement + endomethasone in the root canal: 20 N. The presence of endomethasone
with eugenic in the root canal (two weeks after filling the canal) affected the setting of composer
cement. If a trace of endomethasone remained on the root canal wall, the shear strength of
phosphate cement was lowered. Either phosphate cement or compomer cement may be used.

P041
POSTER
Comparison of Two Bond Strength Testing Methodologies for All-Ceramics
Mutlu Ozcan1*, Mine Dundar2
1Faculty   of Medical Sciences, University of Groningen, Netherlands
2Department    of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey
Material selection, ranking, performances and clinical recommendations on layered all-ceramics
are based on routine mechanical testing methodologies. The objective of this study was to
compare the microtensile (MTBS) and shear bond strength (SBS) testing methods to test the
bond strength of core and veneering ceramics. Four different ceramic veneer/core combinations,
three of which were feldspathic and the other a fluor-apatite to their respectively corresponding
cores namely, leucite-reinforced ceramic (Evopress, Wegold), low leucite-reinforced ceramic
(Finesse, Ceramco), glass-infiltrated alumina (Inceram Alumina, Vita) and lithium disilicate
(Empress 2, Ivoclar) were used for shear and microtensile bond strength tests. Ceramic cores
(n=10/group for each test) were fabricated according to manufacturers' instructions (SBS:
thickness:3 mm, diameter:5 mm and MTBS:10x10x4 mm). The veneering ceramics were
vibrated, condensed in stainless steel molds and fired on the core ceramic materials. After the
firing process, the specimens were tried in the mold for minor adjustments, ultrasonically cleaned
and embedded in PMMA. The specimens were stored in distilled water at 37°C for 24 hours prior
to testing. The bond strength tests were performed in a universal testing machine (cross-head
speed: 0.5 mm/min and 1mm/min for SBS and MTBS, respectively). The bond strengths
(MPa+/-SD) and modes of failures were recorded. Significant difference between the two test
methods and all-ceramic types was observed (P<0.05) (2-way ANOVA, Tukey and Bonferroni).
The mean SBS values for veneering ceramic to lithium disilicate was significantly higher (41+/-8)
than those to low leucite (28+/-4), glass-infiltrated (26+/-4) and leucite (23+/-3) while the mean
MTBS for low leucite was significantly higher (14+/-2) than those of leucite (12+/-2), glass-
infiltrated (9+/-1) and lithium disilicate ceramic (9+/-1) (ANOVA, P<0.05). Both the testing
methodology and the differences in chemical compositions of the core and veneering ceramics
influenced the bond strength of bi-layered all-ceramics.

P042
POSTER
In vitro evaluation of marginal leakage on posterior inlays
Aleksandar Todorovic1*, Slavoljub Zivkovic1, Dusko Gedosev2, Vojkan Lazic1, Aleksandra
Spadijer1
1School    of Dentistry, University of Belgrade, Yugoslavia
2Private   Dental Practice, Mannheim, Germany
The aim of this study was to evaluate the marginal leakage of class II inlays in vitro. Forty-five
extracted, intact, human third molars were prepared with occlusal and proximal class II cavity
preparations and divided into 3 groups. Each group was restored separately with direct resin
composite restorations (group I), porcelain inlays (group II) and CAD/CAM ceramic restorations
(group III). After restoration, the samples were covered with two layers of nail polish and
immersed in 50% silver nitrate solution. The specimens then were sectioned and evaluated for
the penetration in the occlusal and in the gingival walls. Data were analyzed with the
nonparametric Fisher- test. The results showed that there were no significant differences in
marginal leakage between the groups (p>0.05). None of the posterior inlays was able to
eliminate marginal microleakage on the occlusal and on the gingival walls.

P043
POSTER
Bacterial Microleakage of diferent artificial crowns luted with yinc phosphate cement
Vesna Medic, Kosovka Obradovic-Djuricic*, Slobodan Djurisic
School of Dentistry, University of Belgrade, Yugoslavia
Marginal leakage is very often evaluated by measuring the amount or depth of dye penetration
along the tooth/material interface. Unfortunately, different techniques including the dye
penetration do not evaluate some of the dynamic interactions present in the mouth. Clinically, the
region of crown margin is exposed to various influences such as: oral fluids, bacteria, toxins,
acids, components of saliva and a variety of large molecules. All of these may affect the integrity
of tooth/restoration interface. This investigation determines bacterial microleakage along the
tooth/crown interface on teeth restored with artificial crowns that had been in the oral cavity for
more than twenty years. Fifteen human teeth with full veneer or metal /ceramic crowns were
selected for the study. The restored teeth with artificial crowns had a twenty-year history of
intraoral function. Before extraction (for periodontal reasons), an interproximal positive control
bacterial sample was taken from each tooth using a sterile curette. Also, the fluid from gingival
sulcus was taken from each tooth with a sterile pipette. These samples were immediately
transferred to 5 ml transport media. The buccal aspect of each crown was carefully cut through
just to the dentin using a sterile low speed diamond saw. The crowns were fractured from the
tooth with sterile instruments. A spoon excavator was used to scrape a cement sample. All
collected specimens were examined for porphyromonas gingivalis and actinobacillus
actinomicetemcontaminas DNA using the polymerizing chain reaction technique with primary
pairs based on 16S r RNA genes. The obtained results suggest that zinc/phosphate cement does
not offer continual insulation of dentin tissue from oral fluids, although it can not be the only
responsible factor of crowns and teeth longevity.

P044
POSTER
Chewing of patients following partial resection of the mandible.
Tomasz Szyczewski1*, Pawel Piotrowski1, Leszek Lewandowski2
1Department    of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
2Department    of Maxillofacial Surgery, Poznan University of Medical Sciences, Poland
The object of the study was to evaluate the efficiency of prosthodontic rehabilitation of patients
following partial mandibular resection and to evaluate functional disorders. Patients with cancer of
the floor of the mouth qualified for this study. Surgical resection of part of the mandible was
carried out. The patients were treated in the Maxillofacial surgery Department in 2005 and then
supplied with dentures in the Oral Rehabilitation Clinic of Poznan University of Medical Sciences.
A modified Optocal. method was used to evaluate the patients' chewing efficiency. This was
carried out three times: before surgery, 6-8 weeks after surgery but before prosthodontic
rehabilitation and finally, immediately after providing the patient with a denture (partial or
complete, depending on the clinical situation). Partial resection of the mandible reduced
masticatory efficiency considerably, particularly in cases involving extensive surgery. An Optocal.
method showed that prosthodontic rehabilitation improved the patients chewing efficiency.

P045
POSTER
Case report: a new impression technique for craniofacial defects by using custom made
tray
Mustafa Kocacikli*, Suat Yalug, Huseyin Yazicioglu
Gazi University, Ankara, Turkey
Waiting for set up time for different impression and backing materials which are used for facial
moulage impression procedure, takes time. In patients with claustrophobia or achluophobia,
impression procedure can bring about considerable discomfort. A custom made tray with visible
light cure acrylic resin was reinforced in the laboratory after obtaining the shape directly from the
patient's face. Impression was taken by single impression material in one step with this custom
made tray. These procedures saved impression time on the face by using custom made tray
instead of rigid plaster backing for removal of the impression without distortion. This technique
ensures comfort for the patient.

P046
POSTER
An impression procedure for bilateral cleft/lip palate patient: case report
S. Hakan Tuna1*, Filiz Keyf1, Gurel Pekkan2
1Faculty   of Dentistry, Hacettepe University, Ankara, Turkey
2Hacettepe    University, Ankara, Turkey
Patient with bilateral cleft lip and palate (BCLP) had premaxillary displacement in up to three
dimensions. As a result of intrinsic anatomical aberrations such as the absence of alveolar and
palatal hard and soft tissue or contraction resulting from previous surgical repair, orthodontic and
facial orthopedic treatment sometimes fails to resolve this problem. A conventional fixed partial
denture could be used in prosthetic treatment of a BCLP with the entire fixed tooth replacement
over the prepared abutment teeth. Thus good function and esthetics could be achieved. Long-
term success would be more predictable. After cleft palate surgery, there may be a residual
oronasal communication. It usually does not cause a problem for feeding, but speech may be
affected. The purpose of this clinical report was to describe a new impression method for a BCLP
patient with mobile premaxillary segment. A surgically treated 22 old male patient with bilateral
cleft lip and palate was examined clinically. Abutment teeth were prepared and provisional bridge
restoration was made according to diagnostic wax-up. The provisional restoration was sectioned
between central teeth and lateral pontic connection areas. The space between the segments at
right side was increased. This allowed the movement of the premaxilla from deviated left position
to the right. Deviated premaxilla was brought to the position that the tissues allowed
physiologically. The provisional restoration was secured with pattern resin at the connection
areas and removed after polymerization. The provisional restoration was used as a matrix
stabilizing the premaxillary segment and final impressions were made. Type 4 dental stone was
poured in impression and the master cast was achieved. The porcelain fused to metal bridge
restoration was fabricated and cemented in placed. The residual palatal defect was covered with
a metal based obturator and delivered to the patient.

P047
POSTER
Diagnosis of osteoporosis symptoms in mandible based on panoramic radiographs and
fractal dimension
analysis
Beata Borsuk-Nastaj1*, Marcin Kubani2, Slawomir Chaberek3, Przemyslaw Szczyrek2, Elzbieta
Mierzwinska-Nastalska2
1Medical University of Warsaw, Poland
2Department  of Prosthetic Dentistry, Medical University of Warsaw, Poland
3Public Hospital in Otwock, Poland
In planning prosthodontic treatment, the bone volume and local quality is very important.
Complete bone loss and boneskeletal BMD could be partially responsible for high jawbone
atrophy. Panoramic radiography is one of the most common radiological examinations used in
dentistry. The advantages of OPR are high availability and low cost. In correlation with clinical
analysis, OPR enables to diagnose diseases of the stomatognathic system. Although, Klemetti
suggests evaluation of panoramic radiographs in diagnosis of osteoporosis, radiographic
examinations in dentaltreatment planning should prove high specificity and sensitivity. The aim of
the study was to evaluate panoramic radiography and fractal dimension analysis in diagnosis of
osteoporosis symptoms. The subjects were 53 post-menopausal women with diagnosed
osteoporosis, 36 men and 73 women without osteoporosis. The whole group of 109 patients
underwent dental panoramic examinations. Each hard copy was scanned. The same rectangular
ROI of the mandible was measured according to fractal dimension analysis. The assessment of
the fractal dimension consisting of mathematical method of analysis of material's level of surface
complexity was done. T-Student tests were used. A correlation between age and fractal
dimension was assessed. Radiologists and prosthodontists assessed all hard copies according to
Klemetti's method.

P048
POSTER
Occlusal disorder in a patient with mandibula resection: clinical report
Makbule Heval Tasli*, Huseyin Kurtulmus, Tugrul Saygi, Engin Aras
Ege University, Izmir, Turkey
Many pathological cases, traumas can result in mandibular defects. Neoplasm takes the first
place among the causes. Since surgical approach is a preferred way of treatment, mandibular
defects may arise. When the type of the defect is considered; we can classify the mandibular
resections in two parts. 1.The cases in which mandibula continuity is not damaged. 2.The cases
in which mandibula continuity is damaged. Prosthetic treatment is easy when the continuity of
mandibula is not damaged. Restriction in the movement, problem in the inter jaw relations and
change of occlusion are seen when the continuity is damaged. But rarely the same symptoms are
seen although the continuity is preserved. In this case the linearity of opening and closing
movement was lost, inadequacy in function was observed. Generally, patients could not show the
same occlusion after the operation. This study discusses, the approach to remove the rarely
observed malocclusion after the operation of a patient whose mandibula continuity is preserved
after the application of mandibula resection.
P049
POSTER
Application of overdenture in mandibulectomy case: clinical report
Makbule Heval Tasli*, Huseyin Kurtulmus, Engin Aras
Ege University, Izmir, Turkey
Various pathologies may occur in the mandibula. Surgical treatment of these pathologies may
cause different defects. The treatment of these anatomic anomalies is performed through the
combination of plastic & reconstructive surgery and rehabilitation approaches. After the
reconstruction surgery, prosthetic rehabilitation techniques are also used to compensate for the
loss of tooth, surrounding tissue and the functions that are no longer available. In this study, a
telescopic overdenture prosthesis application to a iliac greft applied mandibulectomy patient is
investigated.

P050
POSTER
Spontaneous fracture of an edentulous mandible in a patient with osteoporosis - case
report
Bogumila Fraczak*, Ewa Sobolewska, Halina Ey-Chmielewska
Department of Prosthetic Dentistry, Pomeranian Medical University, Szczecin, Poland
Osteoporosis is a systemic disease, which concerns the osseous systems of 15-50 % of the
world population. The World Health Organization's ranking acknowledged it as a civilization-
related disease. The characteristics of osteoporosis are reduced bone density and bone mass,
which in consequence increase fracture susceptibility. The authors present a case of an 86 years
old edentulous patient with a spontaneous mandible fracture. The patient was under the care of
the Department of Prosthetic Dentistry of the Pomeranian Medical University for 10 years.
Relining of the denture base was carried out at regular periods of time (twice a year) with a soft
liner Vertex Soft. On occurrence of pain symptoms an orthopantomography was carried out and
compared with earlier x-rays. A considerable bone defect in the lower jaw was found. The vertical
dimension of the body and angle of the mandible according to the radiograph was estimated at 11
mm. The bone defect gradually progressed due to coexisting osteoporosis although the patient
was under constant care. As a result of maxillofacial surgery consultation, considering the
patients general health, surgical bone synthesis was abandoned.

P051
POSTER
The effect of deep pressing on the change of thickness of obturator plates from
thermoplastic resin
Wlodzimierz Wieckiewicz1, Ewa Kalecinska2*
1Department   of Prosthodontics, Wroclaw Medical University, Poland
2Department   of Functional Disturbances of the Masticatory System, Wroclaw Medical University, Poland
Optimal management of the wound after surgical removal of a maxillary tumor requires provision
with an obturator plate. In the majority of patients such plates are performed from acrylic material
that has been heat-polymerized, which is a very time consuming technology. Extensive
introduction of products extruded from thermoplastic foil to various branches of dentistry brought
up a question, whether it was possible to use such foil to prepare quicker and cheaper post-
surgical prosthesis? The aim of the study was to: 1. Investigate calibrated thermoplastic foil in
view of the change of its thickness during the process of deep pressing; 2. Evaluate the
usefulness of extruded foil as the base of obturator plates. Twenty discs of calibrated foil with the
diameter of 120 mm were examined. Two kinds of materials were tested: Erkodur 1.5 mm
and 2.0 mm thick and Erkocryl 2.0 mm and 2.5 mm thick. Altogether 5 discs of each type of foil
and each thickness were evaluated. The depth of the bottom of the model depression in relation
to the highest point in the alveolar process ridge was 2 cm. The measurements of the foil
thickness were performed at 3 points: on the ridge of the alveolar process, on the edge of the
post-surgical defect and on the vault of the obturator plate. According to the manufacturer's
information, the thickness of the calibrated plate decreases during the process of extrusion by
20% per 1 cm of its height. Evaluation of the change of Erkodur plate thickness indicated that the
1.5 mm foil became too thin during extrusion and could not be used as the obturator plate base.
On the other hand, 2.0 mm foil could be used. Erkocryl 2.0 mm and 2.5 mm decreased their
thickness after deep pressing by 20% per 1 cm, however they remained rigid enough to be used
as the base for obturator plates. 1.The following foils: Erkodur 2.0 mm and Erkocryl 2.0 mm and
2.5 mm can be used to produce obturator plates. 2.The change of thickness of the calibrated foil
during processing is consistent with the manufacturer's instruction.

P052
POSTER
A tribochemical method of connecting a silicone obturator with the metal base of a
postsurgical dentures
Pawel Piotrowski
Department of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
The author describes a method of post-surgical treatment of patients with considerable loss of the
hard palate and perforation into the nasal cavity. Treatment consists of the preparation of a
silicone obturator and its connection to the metal base of an upper denture by means of a
tribochemical method. The first step in this method (the Rocatec system) was the double
sandblasting (silicatization process) of the metal base. The surface was then silanized and
covered with an opaquer. The next step was to apply the Molloplast B to the conditioned metal
framework. The denture was then flasked and polymerized in boiling water according to the
producers' manual. The Rocatec system provided reproducible results of the tensile stress of
2.26 +/- 0.15 MPa, strength stress 1.41 +/- 0.21 MPa for the chrome - cobalt alloy/ silicone
bond. This technology bonds elastic material to metal frameworks without marginal gaps and
without the need for mechanical retainers. It enables the provision of dentures with high
functionality (involving the retention of the obturator and of the denture itself). Another advantage
was the elimination of food traps and microorganism colonization in the fissure between metal
and silicone. Such appliances are easier to clean and more hygienic for the patient. The author
presented laboratory procedures and described clinical cases of patients provided with metal
dentures with silicone obturators.

P053
POSTER
Computer-aided analysis of speech in patients after mandibular resection
Tomasz Szyczewski1, Pawel Piotrowski1, Leszek Lewandowski2*, Piotr Swidzinski3
1Department of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
2Department of Maxillofacial Surgery, Poznan University of Medical Sciences, Poland
3Department of Biophysics, Poznan University of Medical Sciences, Poland
The aim of the study was to investigate the value of prosthodontic rehabilitation in improving the
speech efficiency of patients who have undergone partial resection of the mandible. Patients with
cancer of the floor of the mouth qualified for this study. Partial resection of the body of the
mandible was carried out in the Maxillofacial Surgery Department in 2005 and then supplied with
dentures in the Oral Rehabilitation Clinic of Poznan University of Medical Sciences. Computer -
aided analysis of sound articulation was used to evaluate the patients' speech efficiency. Speech
was examined before surgery, 6-8 weeks after surgery but before prosthodontic rehabilitation and
finally immediately after providing patient with a denture (partial or complete depending on clinical
condition). Both speech efficiency and sound articulation were markedly worse after jaw
resection, the degree depending on the extent of the surgery. Computer assisted - analysis
showed that prosthodontic rehabilitation improved the patients' efficiency and quality of speech.

P054
POSTER
Impact of orofacial pain on daily living in PTSD patients
Miranda Muhvic-Urek1*, Ivone Uhac1, Zeljka Vuksic-Mihaljevic2, Dinko Leovic3, Natasa Blecic1,
Zoran Kovac1
1Department of Dental Prosthetics, School of Medicine, University of Rijeka, Croatia (Hrvatska)
           Clinic, Clinical Hospital, School of Medicine, Osijek, Croatia (Hrvatska)
2Psychiatric
3Department of Maxillofacial Surgery, Clinical Hospital, School of Medicine, Osijek, Croatia (Hrvatska)
While chronic orofacial pain represents a diagnostic and treatment challenge for the clinician, for
the patients it is a cause of considerable suffering. The aim of this study was to investigate the
impact of orofacial pain on daily living in post-traumatic stress disorder (PTSD) patients. The
group of 40 war veterans with PTSD (median age= 40, range 29-52) was investigated using the
RDC/TMD protocol. Pain intensity as well as the impact of pain/discomfort on daily activities,
ability to work (including housework), recreational, social and family activities were investigated
using the VAS scale (0-10). 94% of PTSD patients reported orofacial pain. On the VAS scale the
subjects evaluated rate/intensity of their orofacial pain as 6.89+/-2.33. The impact of orofacial
pain/discomfort on daily activities, ability to work (including housework), as well as recreational,
social and family activities was indicated to be 6.22+/-2.46, 6.44+/-2.73, and 6.23+/-2.51,
respectively. Pain was positively correlated with daily activities (r=0.62, p<0.001), ability to work
(r=0.66, p<0.001), as well as recreational, social and family activities (r=0.64, p<0.001). This
study indicates that pain/discomfort from orofacial region has a negative impact on activities of
daily living. More effort must be made to reduce patients´ pain and improve the quality of their life.

P055
POSTER
The evaluation of influence of head position on the localization of premature contacts
Monika Lukomska-Szymanska*, Stanislaw Suliborski
Department of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
Many authors postulate the possibility of influence of conditions, in which diagnosis and analysis
of patient's articulation are performed, on the final result of treatment. One of the factors
influencing the diagnosis of occlusion is patient's head position during dental examination. The
aim of this study was to evaluate the influence of head position on the localization of premature
occlusal contacts. Thirty-seven patients, both males and females (aged 17-31) were diagnosed.
T-scan II (Tekscan), using also delta was applied in this study. The occlusal contacts were
registered in three different head positions (head bowing, sitting upright, and supine) during fast,
vertical articulation movements. The localization of premature contacts was then evaluated on the
basis of these results. The frequency of presence of premature contacts varied from 43.2 to 48.6
for delta and from 32.4 to 43.2 for T-scan evaluation depending on head position of the patient.
The accordance of localization of premature contacts depending on head position of the patient
varied from 54 to 67.6 for delta and from 67.6 to 75.7 for T-scan evaluation. 1. The results of the
examined centric relation of premature contacts on the basis of T-scan graphs and delta are
similar. 2. The body position has a very small influence on the localization of centric relation of
premature contact in humans younger than 31 years of age.

P056
POSTER
Recording of occlusal contacts of bridges by T-Scan II system - preliminary report
Andreja Carek*, Jasenka Zivko-Babic, Marko Jakovac
Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Occlusion is one of the basic aspects in functioning of the stomatognathic system. The aim of this
study was to measure simultaneous occlusal contacts bilaterally in prosthodontic patients. Ten
patients with different kinds of bridges were tested for the distribution of occlusal loading. The T-
Scan system was used to analyze the distribution of occlusal loading forces, and occlusal contact
variability changing the colour and the pressed area of foil. Recorded occlusion and occlusion
moves have been stored in a computer program. The results, presented on figures and graphs,
show that occlusal contacts in CR or MIC have not been achieved in the analyzed fixed
restorations as often as in occlusion with natural teeth. Changes within occlusion can be
monitored if information is gathered appropriately before and after prosthetic treatment.

P057
POSTER
Occlusal and Rest vertical dimension in dentate and prosthodontic patients
Robert Antonic1*, Marica Simunovic-Soskic1, Ivone Uhac1, Melita Valentic-Peruzovic2, Miranda
Muhvic-Urek1, Josipa
Borcic3, Daniela Kovacevic1, Alen Braut4
1Department of Dental Prosthetics, School of Medicine, University of Rijeka, Croatia (Hrvatska)
2Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
3Department of Oral and Maxillofacial Surgery, School of Medicine, University of Rijeka, Croatia (Hrvatska)
4School of Medicine, University of Rijeka, Croatia (Hrvatska)
The interocclusal height is determined by the intercuspidation of the two dental arches and
changes during one's lifetime. Although the traditional views support the notion that the
physiological rest position of the mandible is a constant position, new findings indicate that it can
change due to multi-factorial influences such as position of the body, certain medicaments, tooth
loss and occlusal dysfunctions. The goal of the study was to examine in detail the direction in
which the mandible moves between the position of physiological rest and maximal
intercuspidation and to measure the movement of the mandible between the physiological rest
position and 5mm vertical raise. Comparison of the OVD and RVD between eugnetic patients and
patients with dental prosthetics was made. The study was conducted on 92 patients divided into
experimental and control groups. The control group consisted of 50 eugnatic patients, both male
and female, without dental prosthetics. The experimental group consisted of 42 male and female
patients, which had one or more dental prosthetics. The cephalometric points were marked on all
the examined patients and then superimposed and transferred onto a measuring grid. The data
were gathered and processed utilizing Statistics 5.0 and SPSS 10.0 (Statistical Package for
Social Sciences). The obtained results of the OVD and RVD comparison between the
experimental and control group revealed a statistically significant difference. However, in this
study no significant difference was found between the RVD of the control and the experimental
group, while the difference of OVD in the experimental group in comparison with the control group
revealed statistically significant difference. The results of this study indicate that the
unsatisfactory and old, worn-out dental prosthetics can cause changes in vertical dimension in
patients. Such changes occur particularly in patients with removable dental prosthetics such as
complete dentures.

P058
POSTER
Reconstruction of occlusal plane orientation using Camper's line as reference
Asja Celebic1*, Nikola Petricevic2, Marko Guberina2, Stipetic Jasmina2, Ivo Baucic1
1Department    of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
2School   of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
The position of occlusal plane should be as close as possible to the position which was previously
occupied by the occlusal plane of the natural teeth. Most textbooks on removable prosthodontics
advocate that occlusal plane should be parallel to Camper's line. The aim of the study was to
check the accuracy of this method in clinical practice. The participants of the study were fifty-
seven dental students with complete natural dentition and Angle Class I dentition. Photographs
were taken from a distance of 1.5m of the left profile with the subject's head in a natural position
and clenching on a Fox plane and a quick mounted face bow. There was no significant difference
between the position of a Fox plane and quick-mounting face bow on digital photographs, as well
as between occlusal plane and articulator's horizontal plane (P>.05), thus this method was
considered reliable. The angle between Fox plane and Camper's plane was measured on digital
photographs. Statistical analysis was made (descriptives, one sample t-test). Mean difference
between Fox plane and Camper plane was: x = - 4.1 degrees, SD = 5.6 degrees. The range of
inclination between the 2 planes varied from - 15.0 to + 10.5 degrees. Males showed significantly
greater difference between the two planes than females (P<.01). The difference between Fox
plane inclination and the Camper's plane was significant for both genders (Males: t = -7.9, df =
18, P<.01; Females: t = -2.35, d.f. = 37; P=0.024). There was no parallelism between occlusal
plane (Fox plane) and Camper's line, so this method should not be advocated as a choice for
occlusal plane orientation.

P059
POSTER
Orientation of craniofacial planes to gravity horizontal plane
Nikola Petricevic1*, Asja Celebic2, Marko Krajnovic1, Dubravka Knezovic-Zlataric2, Maja Baucic-
Bozic2
1School   of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
2Department    of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Orientation planes for mounting models in articulators are thought to be parallel with real
horizontal plane. The aim of the study was to measure inclination between craniofacial planes
and real gravity horizontal plane. The subjects were fifty-six dental students with complete natural
dentition and Angle Class I dentition. Photographs were taken from a distance of 1.5m of the left
profile and en-face with the subject's head in a natural position and clenching on a Fox plane.
A plumb line was hung from the ceiling to identify gravity vector (true vertical). Perpendicular line
to a true vertical line was drawn on digital photographs (true horizontal). The inclinations between
Frankfort horizontal plane and true horizontal, between Camper's line and true horizontal,
between Fox plane and true horizontal and inclination between bipupilar line and true horizontal
were measured. Statistical analysis (descriptives, t test) was made using SPSS 12 for
Windows. Mean values between the bipupilar line and true horizontal was: x= -.25+/- 1.94
degrees and no significant difference was observed (t= 0.96; P=0.39, NS). Mean difference
between Camper's line and true horizontal was: x= 5.53+/- 7.68 degrees and the difference was
statistically significant (t= 5.39; P<0.001). Mean difference between Frankfort horizontal plane
and true horizontal was: x= - 10.33 +/- 7.68 degrees and the difference was statistically
significant (t= -11.62; P<0.001). Mean difference between Fox (occlusal) plane and true
horizontal plane was: x= 1.42 +/- 5.56 degrees and the difference was not statistically significant
(t= 1.9; P<0.061). Occlusal plane (Fox plane) and bipupilar plane were almost parallel to gravity
horizontal plane in natural head position. The planes of orientation, such as Frankfort horizontal
plane and Camper's line were not parallel to gravity horizontal plane during natural head position.
They were also not parallel to the occlusal plane.

P060
POSTER
Dynamic occlusion for prosthetic rehabilitation - indirect suggestions
Halina Panek1, Danuta Nowakowska2, Beata Panek3, Grzegorz Bielicki4, Elzbieta Rutanska1*,
Malgorzata Mankiewicz
1
1Department of Prosthodontics, Wroclaw Medical University, Poland
2Department of Dental Materials, Wroclaw Medical University, Poland
3Department of Dentofacial Orthopedics and Orthodontics, Wroclaw Medical University, Poland
4Wroclaw Medical University, Poland
Selection of dynamic occlusal pattern for prosthetic rehabilitation is still a controversial issue. The
controversies were mainly caused by inadequate study material usually limited to small groups of
patients treated with selected concept of occlusion. The aim of the study was to evaluate dynamic
occlusion patterns in natural dentition. Moreover, the prevalence of TMDs and periodontopathies
in particular dynamic models of occlusion were evaluated. Material of study consisted of 834
patients with complete natural dentition or single missing teeth without any prosthetic
replacements. The patients were selected from 1500 Wroclaw workers examined during the
periodical medical prophylactic examination. Age of patients ranged from 20 to 63 years. In all
subjects the kinds of occlusion were established while evaluating the static and dynamic contacts
of opposing teeth during centric and eccentric occlusal excursions of the mandible. Moreover, all
patients were examined in order to recognize TMDs and periodontopathies. The following
occlusions were found in studied population: unilateral (O-I) and bilateral (O-II) canine protected
occlusion, group function occlusion (O-III), balanced occlusion (O-IV) and other atypical occlusion
(O-V). Prevalence of above mentioned occlusions was analyzed depending on sex and age of
patients, as well as on the presence of periodontitis and TMDs. 1) Decrease in frequency of O-I
and O-II occlusions may suggest their transformation into O-III occlusion due to tooth attrition, as
it was suggested by McAdam. This phenomenon may, however, indicate that O-III occlusion
provides a better stimulation of periodontal tissues than other dental articulations, and contributes
thus to maintenance of dental arch continuity up to late age. 2) Prevalence of periodontitis and
TMDs is relatively low in subjects with O-III occlusion in comparison to other kinds of occlusion. 3)
The group function occlusion (O-III) seems to be the most suitable occlusal pattern for prosthetic
rehabilitation in middle aged or older patients with partial missing teeth.

P061
POSTER
Disk position of the temporomandibular joint in asymptomatic subject
Tomislav Badel1*, Josip Panduric1, Miljenko Marotti2, Josipa Kern3, Ivan Krolo2, Sonja Kraljevic1
1Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
        Hospital "Sestre milosrdnice", Croatia (Hrvatska)
2Clinical
3Department of Medical Statistics, School of Public Health, University of Zagreb, Croatia (Hrvatska)
The purpose of this study was to determine the disk position of the temporomandibular joint
(TMJ) in young asymptomatic individuals. A magnetic resonance imaging (MRI) examinations
were carried out in 50 TMJs of 25 dental school students (7 males and 18 females) with a mean
age of 23,4 years. Students were clinically examined by means of manual functional analysis and
any clinical signs or history of disk displacement or degenerative joint disease were excluded.
Disk position was analyzed in parasagittal layers of MRI images of TMJ. MR images revealed
anterior disk position in 5 (20%) individuals, or 6 (12%) examined joints. A disk displacement with
reduction was revealed in three joints and in three TMJ disk displacement without reduction.
Asymptomatic disk displacement may signify a potential risk factor for later occurrence of
symptoms and signs of temporomandibular disorders (TMD). Since the ethiopathogenesis of
TMD hasn't been explained, as well as that of the artrogenic form of TMD - internal
derangements, a possible cause of temporomandibular pain in TMD patients could also be the
anterior displacement of articular disk.

P062
POSTER
Temporomandibular disorders in children determined using research diagnostic criteria
developed by Dworkin
and Le Resche
Barbara Gierat-Kucharzewska1*, Jacek Kasperski2, Aleksandra Czelakowska-Rodzaj2, Marcin
Porzycki2
1Department     of Prosthetic Dentistry, Medical University of Silesia, Katowice, Poland
2Medical    University of Silesia, Katowice, Poland
A considerable increase in patients suffering from pain syndromes caused by temporomandibular
disorders (TMD) continues to be recorded. The pain occurs as a consequence of untreated long-
term disorders. The aim of the present paper was to determine if TMDs occur in the group of 13-
year-old children and to discover the causes of TMDs in adolescents. The present study was a
pilot investigation for a population study that aimed to ascertain the frequency of TMDs among
adolescents in various age groups. The study was conducted in a group of 63 children (39 girls
and 24 boys) aged 13. At this age all permanent teeth are completely erupted and all occlusion
relationships are stabilized. During a survey, the following information was recorded: general
health condition, possible pain in the facial area, muscle tenseness in this part of the body, oral
parafunctions, and social situation. The masticatory organ was examined by visualization,
auscultation and palpation, and the achieved results were placed into the RDC/TMD
questionnaire adapted for adolescents. The basic data obtained during the clinical examination
was analyzed as follows: the occurrence of idiopathic pain and its location, pain on palpation:
pain of temporomandibular joints, pain of masticatory muscles, the range of free mandibular
movements, and auscultatory symptoms. Irregularities in the mandible movements were
diagnosed in 23 children. Idiopathic pain of the muscles was recognized in 5 girls, and induced
pain in 9 cases. Subluxation of the temporomandibular joints was observed in 11 children.
Parafunctions occurred in the group of 54 children. TMDs were diagnosed in 42.86% of examined
patients. Parafunctions, which can cause dysfunctions at a later age, occurred in 85.71% of
cases. TMDs occurred in the group of 13-year-old children. A high percentage of parafunctions in
this age group can result in TMD in adulthood. The results obtained justify conducting research
on a larger group of adolescents. This could enable the determination of causes of TMD at such a
young age, as well as early treatment.
P063
POSTER
Influence of neuroticism and extraversion on intensity of temporo-mandibular
dysfunctions and bruxism in
young population
Halina Panek, Malgorzata Mankiewicz*
Department of Prosthodontics, Wroclaw Medical University, Poland
Etiopathogenesis of temporomandibular dysfunctions (TMDs) and bruxism is still a controversial
issue. Some authors stated that the psycho-emotional factors connected with stress or
personality traits may have a great importance in developing the above mentioned disturbances
of the stomatognathic system. The aim of the study was to analyze the influence of neuroticism
and extraversion on prevalence of TMDs and bruxism in young adult population with complete
natural dentition. In such population it was possible to eliminate some local occlusal factors (for
example missing teeth or iatrogenic prosthetic appliances) or general factors (for example
medical problems), which would simultaneously influence the health of the stomatognathic
system. Material of study was a rarely selected population of 303 adolescents - students of The
Secondary School in Wroclaw. All students were male. Age of the subjects ranged from 18 to 22
years. All subjects underwent routine dental examinations and clinical analyses of the
stomatognathic system. The recognition of TMDs was made according to Helkimo's criteria, while
bruxism was measured according to bruxism intensity index by Panek. Moreover, all participants
fulfilled the Eysenck Personality Questionnaire, modified for Polish use by Brzozowski and Drwal.
The questionnaire allows for establishing some personality characteristics, such as neuroticism
and extraversion. For statistical analysis of the results, test ? 2 was used with p-value =< 0.05.
Subjects with TMDs revealed increased levels of neuroticism in comparison to subjects without
the TMDs. Level of neuroticism in subjects with bruxism and without bruxism was not statistically
different. Extraversion, and especially introversion, was not correlated with TMDs or bruxism.
Further studies are necessary to explain the relationship between personality traits and functional
disorders of the stomatognathic system.

P064
POSTER
Measuring of bruxism intensity in epidemiologic studies
Halina Panek
Department of Prosthodontics, Wroclaw Medical University, Poland
Bruxism is considered to be the most destructive parafunction of the stomatognathic system.
However, an index of bruxism intensity, which would be similar to those used in studies on caries,
periodontitis or temporomandibular dysfunctions has not been designed. The aim of the study
was to present the author's design of an index of bruxism intensity, which allows to recognize 4
grades of bruxism: B1 - supposed bruxism, B2 - active bruxism without any greater damages in
hard dental tissues, B3 - active persistent bruxism with pathological abrasion of teeth, B4 -
passive bruxism. The proposed index of bruxism intensity was used in the epidemiological
studies of 1500 Wroclaw workers (656 females and 844 males), who were examined during the
prophylactic periodical medical recall in the Lower Silesia Medical Diagnostic Center DOLMED.
Age of the patients ranged from 20 to 63 years old. 1) In the studied population all grades of
bruxism intensity were found. 2) Grade B1 was not dependent on age. 3) Prevalence of B2
indicated a tendency of diminishing with age, while the frequencies of B3 and B4 increased with
age. 4) The proposed index of bruxism intensity revealed the increase of undesirable effects of
bruxism with age, and, thus, pointed at the necessity of early elimination of the parafunctions.

P065
POSTER
Tongue function analysis in clinical morphological and functional disorders of
stomatognatic system
Maria Prosba-Mackiewicz1*, Bohdan Mackiewicz2, Jurand Mackiewicz1
1Department     of Prosthetic Dentistry, Medical University of Gdansk, Poland
2University   of Gdansk, Poland
Actual studies of morphological structures of stomatognathic system as well as analysis of
correlation between its elements in pathological an physiological functions do not describe tongue
function. Studies on relation to phone articulations are not present. The aim of this study was to
analyze tongue function during phone articulation in clinical morphological and functional
disorders of stomatognathic system. 660 children at the beginning of their orthodontic treatments
have been examined. Ortologophedic methods were used to analyze 4 basic types of phones
articulation. Results indicate that there is a coexistence of functional disorders and morphological
malocclusions. High correlation in group of children with intradental articulation of frontal tongue
part phones and lisping was noticed. Therefore tongue function is one of the etiopathogenic
factors of morphological disorders.

P066
POSTER
The relationship between the signs and symptoms of craniomandibular disorders and
occlusal condition in
students population group
Slobodan Dodic*, Darinka Sinobad-Stanisic
School of Dentistry, University of Belgrade, Yugoslavia
The role of occlusal disturbances in the etiology of craniomandibular disorders ( CMD) is still a
question of controversy in scientific literature and clinical practice. Until the 1980s the occlusal
factors (some types of malocclusions, difference between the RKP and IKP greater than 2 mm,
presence of mediotrusive and retrusive occlusal disharmonies and loss of the posterior teeth )
were accepted as main etiologic factors of functional disorders of the masticatory system.
However, while numerous contemporary studies deny the direct correlation between the occlusal
disturbances and CMD, some others deny any interference of occlusion in the etiology of CMD,
pointing that orofacial structure adapts to certain occlusal disturbances and can function normally
without any signs and symptoms of CMD. The aim of this research was to study the relationship
between the signs and symptoms of craniomandibular disorders and occlusal conditions in a
group of students. The investigation was carried out on 200 students from the Faculty of Dentistry
in Belgrade between 18 and 25 years of age, with preserved natural dentition. The detailed
functional analysis of the OF complex and precise examination of the occlusal condition were
performed . The data were collected in a specially designed questionnaire in order to identify any
signs (symptoms) of CMD and any occlusal disturbances. The presence of signs and symptoms
of CMD was confirmed by evaluating the Hellkimo dysfunction index (Di). The presence of
occlusal disturbances was confirmed by evaluating the index of the occlusal state by Hellkimo
1974.(Oi) The comparative evaluation of values of the Helkimo dysfunction index ( Di) and index
of the occlusal state ( Oi) on the total sample revealed neither signs (symptoms) of CMD nor any
occlusal disturbances in 45 % of the examined subjects ( Di= 0, Oi= 0 ). In 13 % of persons
in the same sample the signs (symptoms) of CMD were confirmed ( Di> 0 ) but, not the presence
of occlusal disharmonies ( Oi= 0 ). 45 % had both the positive dysfunction and positive occlusal
index ( Di >0 and Oi >0 ). They presented the signs and symptoms of CMD and occlusal
disturbances. In 26 % of examined persons occlusal disturbances ( Oi> 0 ) and the presence of
signs (symptoms) of CMD was not confirmed ( Di= 0 ). It was confirmed that among 58 persons
without occlusal disturbances (Oi= 0) 26 (45 %) presented the signs (symptoms ) of CMD (Di> 0)
and among 142 persons with evident occlusal disturbances ( Oi> 0 ), 91 (64 %) presented the
signs and symptoms of CMD. The multiple regression analysis (X2 test and ODDS ratio) revealed
that the probability of having the positive dysfunction index ( Di> 0 ) in persons with occlusal
disharmonies ( Oi> 0 ) was two times greater than in persons without such disharmonies ( Oi= 0
). The comparative analysis of relationship between the signs (symptoms) of CMD and occlusal
condition in 200 students of the Faculty of Dentistry in Belgrade indicated that a greater
percentage of them presented with CMD with occlusal disharmonies. According to the multiple
regression analysis the probability of onset of CMD was 1.2 to 2.5 times greater in subjects with
occlusal disturbances. These results confirmed the significant role of occlusion in the etiology of
CMD.

P067
POSTER
The occurrence of the oral parafunctional habits, malocclusions and the
temporomandibular disorders
Jolanta Nawrocka-Furmanek1, Piotr Zubrzycki1*, Krystyna Rusiniak-Kubik1, Elzbieta
Mierzwinska-Nastalska1,
Malgorzata Zadurska2, Barbara Piekarczyk3, Anetta Zubrzycka2
1Department of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Department of Orthodontics, Medical University of Warsaw, Poland
3Department of Maxillofacial Surgery, Medical University of Warsaw, Poland
Prevalence of oral parafunctional habits and temporomandibular disorders (TMD) in young Polish
adults was reported to increase in the last years. It is suggested that these disorders are brought
upon by school induced stress and stress connected with living conditions. Especially
parafunctions have been frequently observed among patients with occlusal irregularities and/or
malocclusion. The authors studied the stomatognathic systems of 300 students, 20-25 years old,
with complete natural dentition or with single teeth missing. Recognition and diagnosis included
anamnesis and questionnaires concerning parafunctional habits, dysfunctions and TMD
symptoms, as well as orthodontic treatment (already performed or in progress) and also clinical
examination procedures of the masticatory system morphology and occlusion. Statistical analysis
of the detailed data from examinations and questionnaires was conducted. The study revealed
occurrence of mild symptoms of the temporomandibular disorders in 65% of the surveyed group
of students and according to Helkimo's dysfunction index only 35% of the subjects were symptom
free. The prevalence of TMD symptoms concerned mostly subjects with occlusal irregularities
and disorders or those with malocclusion, as compared to those with proper, acceptable occlusal
conditions. There were significant differences in frequency and severity of functional disorders in
subjects with 3-dimensional malocclusions and with transversal deviations between the groups
with other types of malocclusions. Parafunctions were reported in 82% of the surveyed group and
occurred more often in subjects with malocclusion. The incidence of the parafunctional habits was
also significantly higher in women than in men.

P068
POSTER
Discopathy caused by teeth loss
Romana Vosicka1*, Lukas Cupal2, Tatjana Dostalova2,3, Hana Fikackova1, Vera Peterova1
   Faculty of Medicine, Charles University, Prague, Czech Republic
11st
2Department of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
3DMD, Prague, Czech Republic
Discopathy covers a large number of diseases of the temporomandibular joint. It involves the so-
called intracapsular disease, when the disc is affected (adhesion, displacement). The etiology
points at repeated micro-traumas, excessive pressure on the joint, disrupted coordination of the
movement of the joint. If the disc is displaced, it creates a barrier for the head joint when
stretching open. The disease is demonstrated most frequently by a limited asymmetric opening of
the mouth, then the range of opening is within norm, however clicking is present. Case report:
This paper describes a therapy of a 60 year old patient, who presented with pain and clicking in
the left TMJ, while opening his mouth. Clinically, the displacement of the disc was found with a
reposition in the left TMJ, what was confirmed by magnetic resonance. During the examination of
the oral cavity tooth loss was discovered, namely tooth 26 and tooth 36, the consequence of
which was the formation of lock occlusion. This situation from a long-term viewpoint, represents
an articulation obstacle leading often to functional disruptions of TMJ. During the therapy the
authors focused on the removal of the cause through prosthodontic intervention. Metal-ceramic
bridges in the second and third quadrant were made for the patient. In that way, modification of
inter- jaw relationship and withdrawal of the pain from the joint were attained. For the removal
of the displacement of the disc, a lower biting splint was made. During the follow up magnetic
resonance, the state of the joint was shown to have normalized during movement.

P069
POSTER
Mandibular movements recordings in patients with temporomandibular joint disc
displacement
Monika Litko1*, Maria Kleinrok1, Janusz Kleinrok1, Marzena Janczarek2
1Department   of Prosthetic Dentistry, Medical University of Lublin, Poland
2Department   of Interventional Radiology and Neuroradiology, Clinical Hospital, Lublin, Poland
Disturbances in mandibular movements and clicking in the temporomandibular joints constitute
the basic criteria in clinical diagnosis of disc displacement in the intercuspal position. There are
no investigations in literature on mandibular movement disturbances in patients with complex and
simple disc displacement in the intercuspal position in the frontal plane. Magnetic resonance
investigations were carried out in 36 patients who exhibited various types of lateral deviations
during opening, limited lateral movements and (or) clicking during lateral movements, which were
discovered upon clinical investigation. In 34 patients uni- or bilateral compound disc displacement
was diagnosed on magnetic resonance images and in 2 cases simple medial disc displacement
was noted. Incisal point and condylar movements during mandibular opening and lateral
movements were recorded using the optoelectronical device Arcus digma. In all cases recordings
of mandibular movements confirmed the clinical diagnosis. Arclike, sigmoidal or straight lateral
deviation during opening movement was found in 32 patients. In 4 cases, mandibular opening
was normal and bilateral identical anterior-lateral disc displacement was diagnosed on magnetic
resonance images. In these patients uni- or bilateral limited lateral movements and/or typical
condylar movement disturbances, caused by clicking during lateral movements, were recorded.
Lateral movements were in 6 joints normal and in 16 limited. Condylar movements were
recorded in patients with clicking in the temporomandibular joints in the shape of a loop, an eight
and other irregular shapes. Recordings of closing movements were normal in cases with a
reposition of the disc. In cases without reposition, the closing movements were recorded with
various, mentioned above, types of lateral deviations. The presented study indicates that it is
possible to diagnose a temporomandibular joint disc displacement in the frontal plane in the
intercuspal position on the basis of clinical mandibular movement and joint sounds analysis.

P070
POSTER
Mandibular movement in patients with masticatory myofascial pain dysfunction
Ivone Uhac1*, Miranda Muhvic-Urek1, Zoran Kovac1, Dinko Leovic2, Zeljka Vuksic-Mihaljevic3,
Dalibor Lisko1
1Department   of Dental Prosthetics, School of Medicine, University of Rijeka, Croatia (Hrvatska)
2Department   of Maxillofacial Surgery, Clinical Hospital, School of Medicine, Osijek, Croatia (Hrvatska)
3Psychiatric Clinic, Clinical Hospital, School of Medicine, Osijek, Croatia (Hrvatska)
The aim of this study was to determine the effect of masticatory myofascial pain on the function of
the stomatognathic system. A group of 42 patients with myofacial pain of the masticatory
muscles, aged 29 to 52 (median 40 years old) and a control group of 42 healthy individuals, aged
30-57 (median 40 years old) were examined using the RDC/TMD protocol. Mandibular
movements (unassisted opening without pain, maximal unassisted opening, maximal assisted
opening, maximal right and left laterotrusion, and maximal protrusion) were measured using a
precise caliper. In the myofascial pain group the mean value of unassisted opening without pain
was 42.64+/-8.60 mm, maximal unassisted opening was 48.01+/-8.43 mm, and maximal assisted
opening was 49.19+/-8.58 mm while in the healthy control group mean value of unassisted
opening without pain was 51.36+/-5.35 mm, maximal unassisted opening was 51.37+/-5.34
mm and maximal assisted opening was 52.43+/-5.33 mm. The mean value of maximal right
laterotrusion was 9.89+/-2.10 mm, and maximal left laterotrusion was 10.01+/-2.56 mm in the
myofascial pain group compared to the healthy control group where the mean value of maximal
right laterotrusion was 10.59+/-2.09 mm, and left laterotrusion was 10.59+/-1.89 mm. The mean
value of maximal protrusion in the myofascial pain group was 9.12+/-2.15 mm, while in
the healthy control group it was 11.12+/-2.04 mm. Student t-test analysis shows statistically
significant differences between the groups in relation to unassisted opening without pain
(p<0.001), maximal unassisted opening (p= 0.003), maximal assisted opening (p=0.004) and
maximal protrusion (p<0.001). There was no difference between the groups in the way they
opened their mouth. The results of this study suggest that myofascial pain has a huge influence
on mandibular mobility.
P071
POSTER
Temporomandibular joint Computer Tomography in 3D visualization: case report
Maciej Koralewski1*, Ida Krysinska-Grabowska2
1Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Computer    Tomography Laboratory, NZOZ Medical Center, Poznan, Poland
Direct interview and clinical examination are still, in authors' opinion, fundamental diagnostic
methods in identifying Temporo Mandibular Joint (TMJ) disorders. However, in difficult and
complicated cases, examination with Computer Tomography (CT) of TMJ with possibility of 3D
visualization should become the preferred diagnostic method. Authors describe clinical pictures
(photographs) portraying 3D visualizations of difficult and interesting cases of patients with TMJ
in order to present diagnostic potential of the presented method. The pictures were taken during
the treatment of functional disorders of TMJ in a 26-year-old woman. These disorders were
consequences of undiagnosed and untreated TMJ mechanical injury in childhood. When the
patient was 8 years old, she fell down and sustained a fracture of her left collarbone and a bruise
on the left side of her face. Three months after surgical treatment of the fracture and radiological
diagnosis of the total adhesion of the bones, the patient began experiencing migraine headaches.
Deviation from the jaw path to the left side was also noticed. The treatment of pain with
pharmaceutical medication, as well as orthodontic treatment did not bring expected results. Since
the age of 11 the patient felt constant headaches, which got worse after meals and long
conversations. She noticed facial asymmetry that became particularly visible after opening her
mouth wide. The jaw deviation was accompanied by acoustic effects of tracks in TMJ. A renewed
trial of orthodontic treatment was preceded by functional treatment of TMJ disorders. In the
diagnostic process the fracture of the left mandibular condyle was confirmed. Its atypical
adhesion was the result of undiagnosed fracture and the lack of treatment after injury at the age
of nine. Computer tomography in 3 D visualization showed adhesion in the shape of a "sharp tail".
The applied treatment resulted in a considerable reduction of pain from TMJ.

P072
POSTER
Radiological evaluation of temporomandibular joints' structures among patients with
osteoporosis
Krystyna Rusiniak-Kubik1, Iwona Weimert1, Marta Jaworska-Zaremba2*, Elzbieta Mierzwinska-
Nastalska1
1Department    of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Medical   University of Warsaw, Poland
Osteoporosis and osteoporosis related changes in bone mineral density (BMD) affect bones of
the masticatory organ, the prosthetic foundation and structures of temporomandibular joints. In a
group of elderly patients with osteoporosis, prosthodontists should expect changes within
structures of temporomandibular joint with negative impact on functional efficiency of the
masticatory organ and poor prosthetic rehabilitation results. The study included radiological
evaluation of temporomandibular joint structures in elderly patients with advanced osteoporosis
and lowered bone mineral density level (BMD > -2.5). Assessment of the radiological images
revealed pathological changes in the majority of the surveyed patients. Temporomandibular
irregularities and changes most often diagnosed on radiograms were: disturbances in the bone
outline of the condyle, flattened condyle articular surface and the presence of osteophites in the
joint. Also in patients' radiograms hipoplastic changes of the bone of condyloid process were
observed.

P073
POSTER
Occlusal disturbances and location of heads of mandible in fossi of TMJ based on
examination with
Arcus-Digma Apparatus
Bogumila Fraczak1*, Edward Kijak1, Danuta Lietz-Kijak2
1Department    of Prosthetic Dentistry, Pomeranian Medical University, Szczecin, Poland
2Department     of Propaedeutics Dentistry, Pomeranian Medical University, Szczecin, Poland
Occlusal disturbances are considered one of the most important factors leading to dysfunctions of
the masticatory organ. They belong to a group of civilization diseases with an increasing rate of
occurrence, affecting all age groups. They also constitute the third most common dental disease
of a social character, after caries and paradontium illnesses. A complex etiology of disturbances
of the stomatognathic system is a subject of unceasing research. The diagnostic process is
difficult, complex, differentiated and often interdisciplinary. The aim of the paper was to evaluate
the usefulness of instrumental technique in diagnosis of disturbances of the stomatognathic
system, as well as to estimate the degree of dependence between some factors shaping occlusal
surfaces: artificial or natural places of supraocclusion. 55 people aged 15 to 66 divided into three
age groups were examined. In all patients, an analysis of graphic records of the EPA test
(Electronic Position Analysis) in centric occlusion was carried out using the Arcus - Digma
apparatus. The analysis of the obtained graphic records confirmed that occlusal plane
disturbances influenced the quality of the EPA test diagrams recorded by the apparatus.
Pathology appearing in two joints at the same time was observed in 18.18% of the examined.
Disturbances of centralization of heads of mandible in joints were found with the use of apparatus
in 20.8% of patients despite the lack of clinical symptoms of dysfunction. The study of
dependence between the prosthetic treatment and the EPA test results showed that 7 out of 14
people (50%) in whom the apparatus registered the non-central location of the head of mandible
were being prosthetically treated. 1. Instrumental techniques are useful and should be more
widely applied in the basic diagnostics of diseases of the stomatognathic system. 2. The results
of the examination of the electronic position of the mandible (EPA) allow, although not
unmistakably, to confirm the dependence between symptoms of the dysfunction, the disturbance
of the occlusal surface and the location of the heads of mandible in fossi of the joints. 3. The EPA
test can be useful not only in recognizing disturbances, but also in controlling the quality of dental
treatment.

P074
POSTER
Individual intraoral mouthguard programs in prevention of sports trauma
Tomislav Badel*, Vjekoslav Jerolimov, Josip Panduric
Department of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Intraoral mouthguards are an indispensable part of dental care necessary for both levels of sports
involvement – the professional and the recreational. The aim of this paper was to point to the
need for protective devices such as mouthguards in order to avoid possible sports-related
dental/orofacial injuries. Custom-made mouthguards are the most highly recommended
mouthguards. They are produced over a dental cast. In addition, they are the highest quality and
most retentive of mouthguards. Clinical and laboratory procedures of fabrication comprise the
following working phases: preliminary impression of maxilla and mandible in alginate, transfer of
upper dental arch in the articulator and centric record, laboratory fabrication, finishing and
polishing, delivery to patient, grinding and subsequent care. Despite the fact that all the
necessary fitting procedures are accomplished in a few sittings and despite being expensive,
custom-made mouthguards have a number of advantages over other types. They provide the
best comfort during practice sessions and competitions thus offering athletes the best prevention
against orofacial injuries. It is neither easy to prevent such injuries nor to make guidelines on
prevention. Nevertheless, in this review, an effort has been made to raise the awareness of the
athletic community of the need for protective mouthguards because they have proven to be an
effective means of preventing traumatic injuries of the teeth and their supporting structures.

P075
POSTER
Influence of physical training on bite force values for conscripts soldiers
Jasenka Zivko-Babic1*, Melita Zdilar2, Marko Jakovac1, Slaven Zdilar2
1Department     of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
2Ministry   of Defence of the Republic of Croatia, Zagreb, Croatia (Hrvatska)
Bite forces are a prerequisite, expression and measure of masticatory function. Masticatory
habits, consistency of food and physical training are factors that influence the increase of bite
force values. The aim of this study was to investigate if mandatory physical fitness training, period
of three months of basic soldier training, influences values of bite forces in young conscripts. The
study was performed on a sample of 110 conscripts. Bite forces were measured in the beginning
and at the end of the three month period, using electronic gnathodynamometer (EGD) on both
sides in the molar area and both central incisors areas. Dental status, anthropometrical variables
and habits were also registered. Results of measurements were processed using statistical
methods and they indicated an increase in body weight and bite forces in almost all tested
conscripts. It could be concluded that basic soldier training may influence bite force values. as
well as body weight.

P076
POSTER
Influence of surface structure of chosen prosthetic materials on denture plaque adhesion
Bogumila Fraczak*, Ewa Sobolewska, Halina Ey-Chmielewska
Department of Prosthetic Dentistry, Pomeranian Medical University, Szczecin, Poland
Prolongation of human life and dynamic development of prosthetic treatment have caused an
increase in patients using removable dentures for a longer periods of time. Materials used for
denture preparation can be potential pathogenic agents to the oral mucosa. Prosthetic
stomatopathy occurs in 20-70% of patients using removable dentures. The aims of
the study were as follows: 1) Estimation and comparison of surface structures of the most often
used materials for prosthetic dentures, that is: acrylic resin Vertex R.S., metal alloy used for
partial frame dentures and acetal resin Acetal Pressing D. 2) Estimation of denture plaque
adhesion to examined materials. Laboratory specimens, sized 20 mm x 20 mm, were prepared
according to the manufacturer's instructions. The specimen surface was estimated in a
microscope in reflected light. Next, a microbiological examination was carried out with the use of
four basic bacterial cultures (Streptococcus aurelius, Escherichia coli, Pseudomonas erubinosa)
and Candida albicans. An assessment of dental plaque adhesion and colony count on particular
materials was carried out. Initial study results indicated that bacterial adhesion was the greatest in
the case of acrylic resin Vertex R.S. what was probably caused by the material's structure and
laboratory technology. This material is characterized by high porosity, confirmed by clinical
examinations. Denture plaque adhesion to this material is greater than to metal and acetal.

P077
POSTER
Surface roughness of different dental ceramics after acid exposure
Marko Jakovac1*, Jasenka Zivko-Babic1, Sanjin Mahovic2, Lidija Curkovic2, Andreja Carek1
1Department    of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
2Faculty   of Mechanical Engineering and Naval Architecture, University of Zagreb, Croatia (Hrvatska)
It is well known that dental ceramics have excellent esthetics, inertness to different media, good
biocompatibility, low accumulation of dental plaque and good mechanical properties. However,
through the influence of oral cavity, the surface of dental ceramic changes its roughness and
previously mentioned properties are in doubt. The aim of this study was to investigate the surface
roughness before and after acid exposure to two different types of dental ceramics. The samples
were made of feldspathic ceramics (IPS -Classic, Ivoclar-Vivadent) and glass-ceramic (IPS
Empress 2- lithium-disilicate ceramic, Ivoclar-Vivadent). One sample for each material was made
according to manufacturers' instructions in platelet-form, with dimensions 10 x 10 x 2 mm. The
samples were glazed over the whole surface to closely imitate the actual restorations from dental
laboratories. Then, the samples were washed with distilled water in the ultrasonic bath and dried
in the sterilizer. The roughness of each sample was measured on three spots. After that, every
sample was transferred to a plastic polypropylene flask with 4 % acetic acid. The samples were
completely immersed inthe solution. Afterwards, flasks were transferred to thermostatic shaking
assembly at 80 sC, 200 rpm, for 16 hours. Then, the samples were removed from flasks, washed
and dried. The roughness was measured again. The results showed that only feldspathic ceramic
showed significant difference in surface roughness after acid exposure. It could be concluded that
glass- ceramic had better inertness to acid exposure than feldspathic ceramic and this result was
in accordance with the authors' previous studies.
P078
POSTER
Evaluation of Gloss Changes of Provisional Resin Materials by Four Beverages
Filiz Keyf*, S. Hakan Tuna
Faculty of Dentistry, Hacettepe University, Ankara, Turkey
The primary disadvantage of the materials used to construct complete and partial removable or
fixed dentures is that their esthetic, physical and mechanical properties change rapidly in the oral
environment. In case of esthetics, color stability is one of the aspects that requires special
attention, as color may provide important information on the serviceability of these materials.
Color change affects the gloss of these materials. The objective of the present study was to
determine the gloss changes resulting from the testing process of four different beverages in two
types of provisional resin materials. Fifty specimens were fabricated for each material. Each
specimen had one smooth polished surface. The gloss measurements were made with a
glossmeter before testing. Four different beverages (tea, coffee, cola and cherry juice) were used
for testing. Two different angles of illumination (20° and 60°) were used for the gloss
measurements. The materials were immersed in water, tea, coffee, cola and cherry juice
solutions. Water was used in the control group. The gloss of the specimens were measured again
with the glossmeter at the end of the 10th day and 20th day of testing. The Arithmetic Means and
Standard Deviations of each material were calculated and compared to each other statistically
using the Friedman Test, Wilcoxon Test (within times), the Kruskal-Wallis Analysis of Variance
and the Mann-Whitney U-Test with Bonforoni correction (when the difference between the
materials was significant) (p0.05 significant). The results were statistically significant. Tea,
coffee, cola and cherry juice solutions were found to cause changes in gloss of provisional resin
materials. The technique applied for provisional coverage was important for gloss stability.
Indirect provisional materials demonstrated much more gloss change in different beverages than
direct provisional materials.

P079
POSTER
Investigation of effectiveness cleaning product Probett
Prokop Radina1*, Cecilia Christersson2, Neilands Jessica2
1Department    of Stomatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic
2Faculty   of Odontology, Malmo University, Sweden, Sweden
The aim of the study was to compare the effectiveness of cleaning products for resin dentures.
The specific goals of this in vitro study were: 1.Is this product able to remove microorganisms
from denture resin surfaces if brushing is not used? 2.Does the product change the properties of
denture resin surfaces (changes of the contact angle)? 3.Does the product damage
microorganisms? The product Probett (Interclean, DK) contains citric acid, peppermint oil, and
less than 1% of other active substances. The producer recommends six times spray application
(from the distance of 10 cm from the denture surface) with a 10 second break afterwards.
Mechanical brushing was not used. Statistically relevant lower values of microorganisms were
detected between Probett and the negative control (no cleaning) on the surfaces of resins. No
significant differences between Probett and the positive control (cleaning in water only) were
observed. Probett changed the surface properties - the contact angle was lower than before
Probett was used for cleaning. Probett did not damage the cells of microorganisms. The process
of cleaning with Probett influenced the quality of the surface. The surfaces were more hydrophilic
than prior to the experiment. Probett was more effective in cleaning as compared to positive
control, but in this case it was not statistically significant

P080
POSTER
The use of colour guides in aesthetic prosthodontics
Malgorzata Grzelak1*, Marta Jaworska-Zaremba1, Marcin Kubani2, Elzbieta Mierzwinska-
Nastalska2
1Medical   University of Warsaw, Poland
2Department    of Prosthetic Dentistry, Medical University of Warsaw, Poland
Aesthetic effect that satisfies patients is one of the principles in contemporary prosthetics. It is
especially important in the anterior segment, where proper size, shape, symmetry and colour of
the teeth create face harmony. The colour of a tooth is described by four features: shade,
intensity, brightness, and transparency. Mixing them in different proportions gives a range of
colours. Variability in visual shade selection is due to many factors, such as individual differences
in perception of colour, experience of the observer, and viewing environment. Colour guides
describe almost every colour of human teeth. The wide range of ceramic materials and their
colour guides give the opportunity of choosing the best one for each patient, on condition that one
has enough skill in proper use of colour guides. The aims of the study were: to assess colour
choice with application of Vitapan classical, Vitapan 3D Master, and Chromascop, to propose the
optimal method of using colour guides and optimal parameters necessary for this procedure. The
study was divided in two parts. In the first part, the material used consisted of extracted human
teeth and ceramic crowns. In the second part, the dentist evaluated the colour of the teeth in
patient's mouth. The results of the observations were compiled in questionnaires which were
analyzed and compared. The simplicity of the use of colour guides was also taken into account.
1. Vitapan 3-D Master: systematic selection procedure, faster determination of colour, easy
cooperation between dentist and dental technician, equal distance between the individual levels
of value, chroma and hues 2. Vitapan classical: the most popular color guide; greatest accuracy
3. Chromascope: almost always an accurate choice 4. No differences were noted between the
choices made by women and men Clinical implications were described and an optimal method
was proposed.

P081
POSTER
Artificial tooth selection: Could digital photographs be helpful?
Jasmina Stipetic1*, Asja Celebic1, Petra Nola1, Nikola Petricevic2, Dubravka Knezovic-Zlataric1,
Ivo Baucic1, Maja
Baucic-Bozic1
1Department    of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
2School   of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Digital photography is almost universally available. Proper artificial tooth selection is very
important for aesthetic consideration of prosthetic appliance. The aim of this study was to
examine the possibility of calculating the width of a missing central incisor using digital
photographs, as well as to determine best camera-object distance on accuracy of the calculated
tooth dimension. Digital photographs were obtained from 51 dentate subjects using a 3.1 Mega
pixel digital camera from various distances: 35 cm, 70 cm, 1 m and 1.5 m. For the calculation of
the width of maxillary left central incisor (MLI), the following equation was used: MLI(calculated) =
Photographic width of MLI x IPD / photographic IPD. Statistical analysis was made (Kolmogorov-
Smirnov test, dependent sample t-test, correlation and frequencies) using SPSS 10.0 for
Windows. Results revealed no significant difference between the calculated MLI (70 cm, 1 m and
1.5 m distance) and actual MLI. Calculated MLI from 35 cm distance was significantly different
from the actual MLI value (p < 0.01). The highest correlation occurred between calculated MLI
(70 cm distance) and actual MLI. However, the highest percentage of results from a distance of
70 cm was also fitted within +/- 0.3 mm; +/- 0.5 mm and +/- 1 mm difference from the actual MLI
values. However, the results obtained from 1 m distance were also satisfactory. The technique of
use of digital photography is of proven value in calculating the width of a maxillary central incisor.
The photographs using a simple digital camera should be taken from a distance of 70 cm to 1 m.
Digital photographs in a dental office may be helpful for calculating dimensions of artificial teeth in
possible future reconstructive treatment.

P082
POSTER
Spectrophotometric analyzes of different shade guides
Aleksandar Todorovic*, Vojkan Lazic, Aleksandra Spadijer
School of Dentistry, University of Belgrade, Yugoslavia
Statement of the problem: visual technique in combination with color shade guides is still the
golden standard for color matching in restorative dentistry. On the other hand several studies
showed that great number of patients are more or less dissatisfied with the color of their metal-
ceramic restorations. The teeth color determination represents a very important and delicate task,
because it influences the natural look and esthetic value of the future dental restoration. The
purpose of this study was to analyze the most commonly used shade guides with
spectrophotometric method and to point out the deficiencies of the conventional method of color
determination. Vita Easyshade spectrophotometer (Vita, Germany) was used to analyze the color
samples of ten unused Vita classical, Vita 3D Master and already used Vita Lumin Vacum shade
guides. To ensure an identical position of all color samples a transparent silicone mold was
made. The basic parameters of color quality were examined: L, C, H, E, Elc. 480
measurements of ceramic color samples were done and it was established that there were
differences of parameters between the same colors. Statistical processing of the data showed
that the colors differ significantly in three qualities: lightness (L), hue (H), chroma (C). Among
all examined color samples, color C3 got the highest mark and color D3 the lowest. Mean value
+/- standard deviation L Vita 3D Master: - 2.38+/- 1.27 Vita classical: - 2.71+/- 1.10 Vita lumin
vacum: -1.34+/- 1.09 C Vita 3D Master: - 3.38+/- 1.06 Vita classical: - 3.26+/- 0.90 Vita lumin
vacum: -3.02+/- 0.87 H Vita 3D Master: 3.18+/- 1.65 Vita classical: 1.93+/- 1.90 Vita lumin
vacum: 3.64+/- 1.68 E Vita 3D Master: 4.49+/- 0.93 Vita classical: 4.41+/- 0.91 Vita lumin
vacum: 3.63+/- 0.96 According to performed measurements and obtained results it was
concluded that the shade guides are not uniform and that the same colors differ among
themselves in quality, so that mistakes (and misunderstandings between technician and doctor)
are possible when using conventional methods. The important prerequisite of contemporary
esthetic dentistry is to use available techniques for computer color matching.

P083
POSTER
Effect of different cement colors on the final color of In-Ceram
Sema Altunsoy1, Gulay Uzun2*, Filiz Keyf3, S. Hakan Tuna3
1Kavaklydere  Bayyndyr Hospital, Ankara, Turkey
2Hacettepe  University, Ankara, Turkey
3Faculty of Dentistry, Hacettepe University, Ankara, Turkey
The aim of this study was to evaluate the effect of the color of three different post-core materials
and four different colored cements on the color and esthetics of an all-ceramic restoration. A total
of 40 cement samples, 10 per each group (opaque white, white, yellow and brown) were
prepared as discs 14 +/- 0.05 mm in diameter and 0.1+/- 0.01 mm in thickness and three groups
of post-cores (ceramic, Cr-Ni and Cr-Ni+opaque), 10 per each group, were prepared as discs
14+/- 0.05 mm in diameter and 0.5+/- 0.05 mm in thickness. Ten samples of dental ceramic were
prepared as discs in similar dimensions. In each group, while one post-core material and all-
ceramic material remained constant, four different cement colors were studied. Cow dentin was
placed instead of post-core materials as control samples. The color configurations were assessed
with a colorimeter per each group. In the ceramic post-core group, Tukey HSD test showed that
there was a significant difference between the groups in comparison two by two, except white-
yellow group (P0.05). In the opaque white groups, the differences between the groups were found
statistically significant (PDEDE<1).

P084
POSTER
Septofil retraction cords - clinical and microscopic evaluation
Danuta Nowakowska1*, Halina Panek2, Pawel Nawrot1
1Department    of Dental Materials, Wroclaw Medical University, Poland
2Department    of Prosthodontics, Wroclaw Medical University, Poland
Retraction cords are dental materials placed temporary in the gingival sulcus. They are used
during diagnosis, prophylaxis and dental treatment, mainly in prosthetic dentistry for subgingival
finish line exposure. They are used in a dry form or are impregnated or soaked with chemical
hemostatic agents intensifying efficiency of mechanical retraction. They must therefore fulfill a
number of material and clinical expectations. Aim of the study was to evaluate Septofil retraction
cords (Septodont) with regards to their physico-chemical and clinical properties. Evaluation of
Septofil cords was conducted on the basis of following parameters: material, structure, thickness
and color. The clinical evaluation was performed during the preparation of 30 abutments for fixed
prosthodontics with subgingival margins. One-cord and double-cord packing techniques and
chemomechanical methods were used. Cords were soaked in aluminum chloride solution
(Racestypine, Septodont). Clinical retraction efficacy was controlled according to Jokstad's
criteria: easiness of packing into gingival sulcus, tendency towards fraying, hemostasis time,
effectiveness of tissue displacing, lack of bleeding at removal of the cord and dryness on the
gingival sulcus. Moreover, structure evaluation of the retraction cords was made with the use of a
microscope. Septofil retraction cords are made of natural material (cotton), knitted of four
thicknesses: ultra thin (0.5 mm), thin (0.65 mm), medium (0.80 mm), thick (1.0 mm), and contrast
color to dental and gingival tissues (dark blue, orange, lily, green). Microscope evaluation
revealed that single fibers combine in compact structure and do not exhibit fraying tendencies.
The clinical evaluation of the patients during prosthetic treatment showed following properties of
the cords: easiness of packing the cord into gingival sulcus, low tendency towards fraying,
relatively short hemostasis time, high effectiveness of the tissue displacement, sporadic
occurrence of bleeding at removal of the cord and satisfactory level of dryness in the gingival
sulcus. 1) Evaluation of the cords with regard to material aspects showed their physico-chemical
properties worthy of recommendation 2) The clinical evaluation on the basis of the
aforementioned criteria proved high efficiency of the retraction cords in dental practice.

P085
POSTER
Gingival retraction preferences: methods and chemical retraction agents used by Polish
dentists
Danuta Nowakowska1, Halina Panek2, Malwina Nowakowska3*
1Departmentof Dental Materials, Wroclaw Medical University, Poland
2Departmentof Prosthodontics, Wroclaw Medical University, Poland
3Warsaw School of Economics (student), Poland
Dentists use gingival retraction procedures during diagnosis, prophylaxis and treatment in the
area of gingival sulcus. There are many retraction methods, which may be divided into surgical,
mechanical and chemomechanical ones. In the United States, many authors conducted surveys
on methods and chemical retraction agents and on preferences of dentists in general practice.
However, in the European Union similar surveys were conducted only in France. There is no
respective survey conducted among dentists in Poland. The aim of the study was to research the
frequency of use of retraction procedures, methods, preferences and popularity of materials and
chemical retraction agents used nowadays by Polish dentists. Questionnaire designed specifically
for the purpose of this study was addressed to dentists of different specialties from all over
Poland gathered at the X Congress of Polish Dental Association held in 2004 in Wroclaw. Results
collected ware analyzed using Chi-2 test. Responses were obtained from 137 dentists (111
women and 26 men) in the ages of 25-68 years. Among them were 114 specialists and 23
general dentists. Retraction procedures were reported to be used by 105 dentists (76.6%
respondents). Multiple answers were possible in the choice of retraction methods. It was
established that 21.9% dentists prefer surgical method, and among them 13.3% persons
used electrosurgery. Majority of respondents (99,0%) chose mechanical retraction and in this last
group 96.2% persons used retraction cords and 13.3% - occasionally retraction bands. 94.3 %
respondents chose Chemomechanical retraction. Most frequently used retraction cords were
knitted and braided ones (62.8%) and twisted (37.2%). Astringents were generally used by 78.9%
of dentists: with aluminum chloride (56.6%), ferric sulfates (18.6%), aluminum sulfates (3.7%),
while epinephrine was preferred only by 21.1% dentists. 1) Polish dentists, similarly to dentists in
other countries, preferred chemomechanical method with the use of retraction cords and
chemical retraction agents. 2) Knitted and braided cords were most frequently used as retraction
materials. 3) Astringents were most commonly used chemical retraction agents in general
practice.
P086
POSTER
Mechanism of forming cervical lesions during overloading molars -FEA
Beata Dejak
Department of Prosthodontics and Oromandibular Dysfunction, Medical University of Lodz, Poland
The purpose of the study was to determine the mechanism of cervical lesion formation in
mandibular molars during tooth overloading. The investigation was performed by means of finite
element analysis with the use of contact elements. A two-dimensional model of the mandibular
first molar and the crown of the opposing maxillary molar in frontal section were created.
Computerized simulation of chewing a morsel with high elastic module, grinding and clenching
was performed. During these simulations the values of stresses in the mandibular molar were
calculated. To evaluate the effort of anisotropic teeth tissues the Tsai-Wu criterion was applied.
Significant pressures were exerted on lingual cusps of the mandibular molars in simulations of
physiological and pathological load on these teeth. As a result, tensile stress appeared in enamel
elements close to the cemento-enamel junction at the buccal side of the studied tooth model,
which exceeded the strength of the enamel. In this place, the Tsai-Wu strength ratio reached
values higher than 1. According to Tsai-Wu criterion these elements had been damaged, and
thus were removed. During subsequent overloads of the tooth model with the initiated cervical
lesion, the Tsai-Wu ratio exceeded 1 along the dentino-enamel junction, creating an overhang of
enamel in cervical area. Application of minimal horizontal force led to a fracture of this fragile
unsupported enamel fragment. Tooth overloads, even during physiological activities, may cause
enamel damaging at the cemento-enamel junction and lead to initiate a cervical lesion. Further
mechanism of lesion formation is based on undermining the enamel along its junction with dentin,
and then chipping the overhanging enamel fragment. This process repeats during subsequent
tooth overloads and causes enlarging of the lesion.

P087
POSTER
Examination of palatal taste receptors in adults
Ryszard Koczorowski1, Renata Kaczorowska2*, Antoni Pruszewicz3
1Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
       Dental Practice, Poznan, Poland
2Private
3Department of Phoniatry and Audiology, Poznan University of Medical Sciences, Poland
Disorders of the sense of taste (dysgeusia) may be symptoms of a number of illnesses and
appear as first- and secondary ailments, especially in elderly people. The perception of taste may
vary from one individual to another and affects his/her everyday diet, health, hygiene and
susceptibility to caries. The literature provides little information on palatal taste buds. The aim of
this study was to evaluate perception and identification of four basic tastes on the hard and soft
palates of adults and to determine the taste threshold. The subject group comprised of 50 adults,
aged 19-80, who did not report any disorders of taste and smell. Each member of this group
underwent one Taste Perception Threshold Test and one Taste Identification Threshold Test on
the hard and soft palates using the Bornstein method. Three different solutions (Io,IIo,IIIo) of test
substances were used for bitter, sour, salty and sweet tastes. It was demonstrated on the basis of
the clinical tests that four tastes were identified on the hard palate, of which the sweet taste was
identified the worst. The highest percentage (over 50%) of the subject group perceived the bitter
and salty tastes on the hard palate. These tastes were also identified the best. Tests conducted
on the soft palate indicated that it allowed for perception of all the four tastes but the sweet taste
was identified the worst. Perception of the bitter taste in percentage terms was far greater on the
soft palate than on the hard palate. Taste identification was significantly better on the soft palate
than on the hard palate.

P088
POSTER
A vertical root fracture of an abutment tooth
Canan Hekimoglu
Faculty of Dentistry, Hacettepe University, Ankara, Turkey
Insufficient sound dentin leads reinforcement of the tooth with dowel and core system. The
purpose of the use of a dowel is to protect remaining tooth structure and to provide the retention
for a crown. Various dowel designs have beendeveloped and used with core. Design, diameter
and number of dowels, embedment depth, cement type, installation stress, stiffness, these are
some of the major concerns leading to restoration failure. A core system could transfer occlusal
forces intraradicularly leading to vertical root fracture (VRF). VRF can be diagnosed depending
on sings, symptoms and radiographic findings. However, findings can be confused with other
dental problems. The aim of the paper was to describe a VRF of an endodontically treated
abutment tooth of a bridge without any clinical signs and symptoms. A 64-year old man
demanded a repair of porcelain fracture on the pontic of a metal ceramic three-unit bridge. The
patient's history indicated that a metal ceramic bridge was cemented five years ago. He didn't
experience any problems. All prostheses were carefully examined for technical complications.
There was a cohesive fracture within porcelain on the facial surface of problematic pontic. It was
decided to repair fractured pontic with intraoral ceramic repair system. Radiographic examination
revealed a VRF of the anterior abutment tooth-mandibular left, the second premolar treated
endodontically with tapered self threading screw dowel and a radiolucent area around it. This
result was surprising, because there were no clinical signs and symptoms. However, no deep
pocket was measured around the mentioned tooth in spite of the fact that deep periodontal
pocket is a common finding in such cases. It was decided to remove the bridge and extract the
involved tooth. A conventional removable partial denture was planned following complete bone
healing after 8 months.

P089
POSTER
On possibilities of reconstruction of broken frontal teeth in children
Joanna Chlapowska*, Maria Borysewicz-Lewicka
Department of Paedodontics, Poznan University of Medical Sciences, Poland
Broken frontal teeth as a result of mechanical injury can be a serious clinical problem, especially
when a substantial part of the crown is lost. The most frequently applied procedure is prosthetic
reconstruction, although reconstruction with a composite or the broken piece of the patient's own
tooth can also be made. The paper presents long term observations of teeth reconstructed after
serious damages to the crown caused by mechanical injury. Case 1. A 12-year-old girl broke
almost the whole crown of the first incisor tooth; she did not experience autopathic pain. No pulp
denudation was revealed on the day of the accident. Radiological examination revealed
incomplete development of the root. The treatment was to cover the denuded dentine with
material based on calcium hydrochloride and to place a veneered prosthetic crown. After
apexification of the tooth, its crown was reconstructed with a composite. The result 13 years later
continued to be satisfactory, despite certain undesired changes in the marginal periodontum.
Case 2. A girl 11-years old broke the crown of the second lower incisor. The patient was
examined one day after the accident. Pulp denudation occurred over a significant area, indicating
the necessity of complete pulp extirpation and immediate filling of the tooth canal with material
based on calcium hydrochloride. The broken off fragment of the crown was united with the root of
the tooth by the light-hardening material. The aesthetic effect was very good. Eight years after the
treatment, radiological control did not reveal any pathological changes. Changes near the
periapical tissues were detected after 12 years. The patient did not complain of pain and the
appearance of the tooth was satisfactory. The above-described clinical cases confirm that it is
possible to use the above mentioned therapeutic procedures in children. Nevertheless, a long-
term control is needed to study the risks of development of undesirable symptoms.

P090
POSTER
Immediate prosthetic treatment of children after loss of permanent maxillary incisors
Karina Pawlaczyk
Department of Paedodontics, Poznan University of Medical Sciences, Poland
Children with losses in their permanent dentition due to trauma, require interdisciplinary treatment
(orthodontic, prosthodontic, pedodontic, surgical and radiological) to achieve proper bite relations
and the best esthetic results. The aim of this presentation was to underline the meaning of the
first stage of comprehensive treatment-prosthetic treatment, which provides proper esthetics to
the patient. The author also indicated the correlation between existing malocclusion and a
tendency to the injuries caused by protruded teeth and malpositioned dental arches. Two different
ways of immediate prosthetic treatment in cases of patients with missing permanent maxillary
incisors due to trauma were described. Both patients suffered also from coexisting malocclusion.
They had protruded upper anterior teeth, which were prone to injures. A 9-year old female patient
was equipped immediately after trauma with removable prosthesis. The other 13-year female
patient had an acrylic tooth attached to the adjacent teeth using orthodontic steel wire, 0,14
inches. The restorations in both cases allowed the patient to achieve proper esthetic appearance.
Meanwhile, the plan of the orthodontic treatment for each patient was prepared and in both cases
it was to be introduced in the next stage of treatment. Patients after trauma of the anterior region
of the dental arch should have the restoration of the lacking teeth done as soon as possible to
provide them with esthetic appearance. Every treatment should focus on the improvement
of the function of the masticatory system taking also into account patient's mental well-being.

P091
POSTER
The causes of pseudolack of upper incisors
Maria Pospieszynska
Department of Orthodontics, Poznan University of Medical Sciences, Poland
The aim of the work is to present causes of pseudo-lack of upper incisors in children. The
subjects were five children aged from 7 to 11, among whom 4 were recognized to lack one of the
medial upper incisors, and in one child additionally more lateral incisors were missing. To explain
why the teeth were lacking a panoramic radiograph examination was performed. Pseudo-lack of
previously mentioned teeth was recognized in all children, at the same time in four of them, it was
conditioned by retention of medial incisor due to changes in the position in the bone, making it
impossible for the tooth to erupt. In two children this change was congenital and was based on
the turnover of the tooth bud by 180 degrees, with the incisive edge in the direction of the base of
the nose. In one child, as a result of trauma to the milk tooth the crown of the permanent incisor
was bent in relation to the root. Another child lacked a tooth as a result of the presence of
granuloma in the area of the apex of the root of persistent milk incisor. On the other hand in the
12-year-old girl the lack of two incisors in the maxilla was due to a considerable backward
mineralization process of these teeth. The causes of pseudo-lack of upper incisors can be both
congenital and acquired. Congenital causes include endosteum turnover of the tooth bud by 180
degrees and the delay of mineralization. Trauma connected with "driven" milk incisor or the
presence of granuloma around its root are the acquired causes.

P092
POSTER
Anti-inflammatory effect of LLLT in patients with denture stomatitis
Vjekoslav Jerolimov1*, Mirela Maver-Biscanin2, Marinka Mravak-Stipetic3, Alen Biscanin4
1Department  of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
        Hospital Centre Zagreb, Croatia (Hrvatska)
2Clinical
3School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
4General Hospital Ogulin, Croatia (Hrvatska)
Denture stomatitis (DS) is a common inflammatory condition that affects denture wearers.
Different treatment methods have been suggested to treat this symptom, none of which is proven
to be absolutely effective. The aim of this study was to examine, in vivo, the effect of diode laser
irradiation on palatal inflammation, in denture wearing patients. Patients with clinical evidence of
DS (n=70) participated in this parallel, single blind and placebo, controlled study. The subjects
were randomly assigned to four treatment regimens: 1)685 nm laser irradiation group (30 mW;
3.0 J/cm2; 10 minutes); 2)830 nm laser irradiation group (60 mW;3.0 J/cm2;5 minutes).A
semiconductor diode laser was used in both treatment cases for five consecutive days, using
continuous working mode; 3)placebo group(sham irradiation of palatal mucosa and denture
base);4)antimicotic group(self treatment with myconazole oral gel and antiseptic solution for the
dentures). The clinical condition of the palatal mucosa, initially and after the final treatment, was
evaluated using Newton criteria: 0=no inflammation; 1=pin-point hyperemia; 2=diffuse erythema;
and 3=papillary hyperplasia. Although 830 nm laser wavelength showed greater anti-
inflammatory effect when compared to the 685 nm., no statistically significant difference
was found between these two groups(2=1,121; p=0,571). When comparing the laser treated
groups to the antimicotic control group, no statistically significant difference was found either
(2=1,876; p=0,391). Analysis showed statistically significant differences between laser treated
patients and the placebo control group (2=16,563; p<0,001) with respect to palatal inflammation,
before and after the treatment. LLLT showed significant anti-inflammatory effect. Therapeutic
effect was achieved in the laser treated groups, while most subjects in the placebo group showed
unchanged conditions after final treatment. A combination of antimicotic oral gel and antiseptic
solution showed similar therapeutic effects to laser irradiation.

P093
POSTER
Candida associated denture stomatitis in patients after immunosuppression therapy
Magdalena Golecka1*, Elzbieta Mierzwinska-Nastalska1, Malgorzata Grzelak2, Urszula
Oldakowska-Jedynak3, Leszek
Paczek3
1Department    of Prosthetic Dentistry, Medical University of Warsaw, Poland
2Medical   University of Warsaw, Poland
3Institute of Transplantology, Medical University of Warsaw, Poland
Patients who undergo kidney or liver transplantation receive a long lasting immunosuppressing
therapy. The unfavorable symptoms of this therapy are a result of immunodeficiency and side
effects typical for each kind of medicaments. The aim of this study was to establish the frequency
and intensity of denture stomatitis and oral candidiases among denture wearing patients who
were treated with immunosuppressing drugs. The study was carried out in the group of denture-
wearers with a transplanted kidney or liver who had been treated with immunosuppressing
medicaments. The control group included healthy people wearing dentures. In both groups,
physical and clinical examinations were performed. Anamnesis covered nonobjective symptoms
in oral cavity, hygienic habits of the mouth and time span during which the denture was used.
Conditions of oral mucous membrane, angular cheilitis as well as denture stabilization
were also evaluated. In both groups mycological investigations were made by taking the direct
swab from the oral mucosa and the surface of dentures and inoculating it on Soborauda agar.
The results of our study suggest that patients with immunosuppression were more frequently
subjected to Candida albicans infections. Stomatitis was more common in this group of patients.

P094
POSTER
Sensitivity of Candida' strains on selected antifungal preparations in vitro
Marta Jaworska-Zaremba1, Monika Wojda2*, Malgorzata Grzelak1, Marcin Kubani2, Elzbieta
Mierzwinska-Nastalska2
1Medical   University of Warsaw, Poland
2Department    of Prosthetic Dentistry, Medical University of Warsaw, Poland
The living conditions, as well as the option of refunding the costs of medications as a part of
contracts with the National Health Service are the reasons of continually increasing number of
denture wearers. Candida-associated denture stomatitis is a recurrent and unwanted effect of
prosthetic dentures' use. Data available so far indicates the occurrence of denture stomatitis in
11-67% of denture wearers. Candidal infection is one of the main reasons for the development of
changes in the prosthetic foundation. Local therapy of denture stomatitis may consist of: -
rosthetic medication - surgical treatment - pharmacological medication - combined prosthetic and
pharmacological medication. The aim of the study was to determine the degree of efficiency of
selected antimycotic preparations like Flukonazol, Itrakonazol, andCitrosept. Materials for the
study were 19 strains of Candida obtained from patients by swabbi ng the oral mucosa and
compared with standard strains. The strains' sensitivity to preparations was estimated by using
acrylic discs (Softerex) saturated with Flukonazol, Itrakonazol and Citrosept. The discs were
plated on C.albicans yeast-selective medium Casiton and incubated for 48 hours at 30 degrees
C. The inhibition zone of Candida's growth was evaluated after 24 and 48 hours. The efficiency of
Flukonazol was 73,68 %, Itrakonazol 31,57%, Citrosept 100%. 1.Flukonazol introduced into
the Soferex can be considered as medication for Candida-associated denture stomatitis. 2.
Citrosept is an efficient and cost-effective anti-fungal agent and may be an alternative solution to
the treatment with polyenes.

P095
POSTER
Disturbances in masticatory organ and development of defects of non-carious origin
Anna Prymas*, Hanna Napiontek-Kubanek, Janina Stopa
Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
In clinical practice, development of defects of non-carious origin appears with continually
increasing frequency. Functional disturbances in oral cavity, resulting in development of inner
tensions represent one of the factors which promote development of such defects. Neck of a
tooth is particularly prone to be affected by such forces. The extent of inner tensions and the
stretching phenomenon in the region of the neck of a tooth affect balance of stress acting on
dental tissues and their propensity to injury. The present study aimed at evaluation of frequency
of functional disturbances in the masticatory organ and at probing the potential relations between
manifestation of such disturbances and presence of defects of non-carious origin. The total
number of 115 individuals, selected at random and aged between 19 and 70 years were
examined and the total number of 43 individuals were identified, in whom defects of non-carious
origin were noted. Most frequently observed were abrasive defects and abfractions, located in the
cemento-enamel junction. The remaining 72 individuals exhibited no defects of non-carious
origin. Results of studies, including malocclusion, parafunctions and lack of individual teeth were
documented in a special study chart, supplemented by a questionnaire with questions related to
exposure to stressful situations and harmful habits. The obtained results were subjected to
statistical analysis using the Chi2 test. Among the 43 individuals with non-carious defects, 33
individuals manifested functional disturbances in masticatory organ (76.7%), while among 72
individuals with no defects 38 individuals (52.7%) suffered from such disturbances. The latter
involved most frequently parafunctions (tightening of teeth, gnashing of teeth), malocclusion
(cross bite, supraocclusion, crowding of teeth), lack of teeth (alar and junctional). In a given
individual they were present individually or in groups. In individuals with functional disturbances in
masticatory organ defects of non-carious origin were found to be more frequent and the two traits
manifested a significant relationship.

P096
POSTER
Occlusal surface of premolar teeth - odontoglyphic, histomorphometric and
electronomicroscopic studies
Katarzyna Mehr1, Pawel Piotrowski2, Teresa Matthews-Brzozowska3,4*
1Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Department of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
3Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
4Department of Dentofacial Orthopedics and Orthodontics, Wroclaw Medical University, Poland
Progress in science and technology has lead to the development of new reconstructive
techniques in conservative dentistry and prosthodontics. The studies aimed at evaluating the
occlusal surfaces of premolar teeth in respect to their odontoglyphic pattern, as well as
histomorphometric and electronomicroscopic (SEM) patterns. The material comprised of 51
human erupted premolars. Surfaces of the teeth crown were intact and devoid of clinically
detectable caries. The odontoglyphic pattern recorded by photographs and drawings was used to
determine the planes for sectioning. The crowns were cut along the long axes of the teeth. Three
sections of the crowns were devoted to histomorphometric studies and one to SEM studies (JSM
35C, Jeol). Preparations were stained with H+E and Mallory technique and evaluated on both
sides. The histomorphometric patterns and measurements were documented under a Nikon
Eclipse E600 optical microscope, assisted by MicroImage 4.0 software. The data were subjected
to statistical evaluation. Extensive variability was noted in every type of odontoglyphic
microstructure. Histological examination showed that prisms in cross-sections appeared in linear,
wavy and spiral forms. Enamel lamellae appeared relatively frequently, running from the enamel
surface to various depths within the enamel. They frequently commenced in microindentations
of the occlusal surface. The SEM confirmed the location of these lamellae and the presence of
organic matrix in the microindentations. Some SEM patterns suggested that the lamellae could
reflect mechanical tensions. Cracks resulting from these tensions could fill with a matrix
containing organic matter. Fairly frequently the lamellae were surrounded by areas of
demineralization, detectable both in histological preparations and in SEM examination. Extensive
variability was noted in enamel morphology in projection of occlusal surface, which may be
significant in clinical dentistry. The results suggest a need for individualized selection of
reconstructive techniques.

P097
POSTER
Enamelodentinopathies in adolescents living in Legnica Cuprum Mills Region
microintoxicated by heavy metals
Barbara Bruziewicz-Miklaszewska1, Beata Panek2*, Monika Szymaniak3, Ewa Mendrela1,
Malgorzata Norowska3,
Michal Karolewski3
1Departmentof Prosthodontics, Wroclaw Medical University, Poland
2Departmentof Dentofacial Orthopedics and Orthodontics, Wroclaw Medical University, Poland
3Wroclaw Medical University, Poland
Enamelodentinopathies (EDPs) are defined as pathological changes in hard dental tissues due to
disturbances in the mineralization process. The etiologic factors of EDPs are very complex.
Pollution of the environment with some heavy metals is considered to have a great impact on
these diseases. The aim of the study was to establish the prevalence of EDPs in region with high
environmental pollution with Pb, Cu and Zn, and to compare the obtained results with those found
in other regions of Poland. The authors studied a group of 1000 school children aged 15-18
years. All the children were examined clinically in natural lighting. The DDE index was used to
record particular kinds of EDPs. The DMF index was also employed. The children were asked
about any pharmacological therapies they underwent and illnesses that occurred prior to the
eruption of permanent teeth. Moreover, they were asked about drugs used and diseases their
mothers had during pregnancy. EDPs were found in 48.8% children. The disturbances were more
frequent in girls. Frequency of particular EDPs was as follows: discoloration - 28%, discoloration
plus hypoplasia - 7%, hypoplasia - 13%. Discoloration was placed in 41% in the upper anterior
teeth region, 9.7% in the upper right posterior teeth, and in 10.2% in the upper left posterior teeth
region. The appropriate data for lower teeth regions were: 18%, 11.1% and 10%. Among
discoloration cases the percentage of white-yellow stains was 62%, while the brown ones - 38%.
The average DMF in children with EDPs was 9.1, and was higher than in those without the EDPs
(8.2). 1) Prevalence of EDPs in Legnica region reveals a moderate level in comparison to other
regions of Poland; 2) White irregular tooth discoloration was the most frequent EDPs in Legnica,
however its prevalence was similar to that in other regions of Poland; 3) Frequency of hypoplasia
in Legnica was higher than that in Gdansk and Lublin region; 4) Teeth with EDPs are more
susceptible to caries; 5) EDPs in anterior teeth may cause serious esthetic and psychological
problems for adolescents; 6) There is a need to improve environmental conditions in Legnica
region to diminish the increase of EDPs.

P098
POSTER
The role of strontium in remineralization of artificially decalcified enamel
Anna Surdacka1*, Elzbieta Kaczmarek2, Bogdan Stachecki3
1Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
2Department of Clinical Pathomorphology, Poznan University of Medical Sciences, Poland
3Department of Biochemistry, Poznan University of Medical Sciences, Poland
The role of strontium ions in natural human environment has long been perceived. Therefore,
their usefulness for oral hygiene agents has been encountered. The aim of our study was to
evaluate surface and lateral sides of teeth enamelexposed to synthetic hydroxyapatite toothpaste
(group I) and synthetic hydroxyapatite toothpaste supplemented with strontium ions (group II) in
in situ conditions. The material consisted of 20 healthy premolars extracted for orthodontic
reasons and sectioned into samples. Artificial demineralization was induced on their enamel. The
in situ model was developed by placing the samples on the buccal surfaces of the first molars in
healthy subjects and exposing for 3 or 6 months to the toothpaste. The quantitative X-ray EDS
microanalysis was then performed to examine Ca, P and Sr content on the enamel layers at 15,
30, 60 and 100 microns deep. Statistical analysis of these results was performed with non-
parametric ANOVA. The results showed that Ca content in both groups was significantly lower
after 3 and 6 months of toothpaste activity than soon after demineralization. In group I, P content
was significantly higher on the enamel layer of 30 um deep than at baseline while Sr content
significantly increased at the same depth in both groups. Strontium toothpaste promoted the
incorporation of Sr into the sub-superficial enamel layers rather than the remineralization process.

P099
POSTER
Application of laser fluorescence technique for diagnosis of caries on occlusal surfaces of
lateral teeth
Anna Wedrychowicz-Welman*, Anna Prymas, Pawel Lewandowski
Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
Difficulties of appropriate diagnosis and monitoring of caries progress of lateral teeth occlusal
surfaces, reflecting anatomical structure of the teeth, have induced attempts to develop new,
more objective methods of detecting caries lesions. The present study aimed at comparing
efficiency of caries detection on occlusal surfaces on lateral teeth using clinical examination
according to the scale of Rip and Wolff on one hand or using laser fluorescence technique
(DIAGNOdent). The clinical evaluation included 329 lateral teeth (204 premolars and 125 molars)
with no fillings or pit and fissure sealants in 50 patients aged 17 to 25 years. Every surface was
examined using dental probe and a mirror and the results were documented in a four-stage scale,
according to Rip and Wolff (1st examination) and using DIAGNOdent (Kavo), employing the scale
of Lussi (2nd examination). Occlusal surfaces of lateral teeth identified in the 1st examination as
exhausting criteria of code 2/3 (193 teeth) qualified for treatment using preventive resin
restorations (PRR). The diagnosis established during 1st and 2nd examinations was verified
during preparation of the lesions concluding the diagnosis of Caries superficialis, Caries media or
absence of caries. Input of individual diagnoses in the total material was calculated. In the 1st
examination 41% of occlusal surfaces exhausted criteria of code 2 (suspicion of caries) and 18%
of cases corresponded to caries (code 3). In the 2nd examination 18% of the teeth (values
ranging from 21 to 29) required prophylactic or invasive actions (depending on caries risk
involved) and 23% of the teeth (values above 30) qualified for conservative treatment. In the
course of preparation, presence of caries was indicated in 95% of the teeth. The performed
studies showed that neither of the applied diagnostic techniques could exclude erroneous
diagnosis of caries. Therefore, in doubtful cases it seems worthwhile to employ a few diagnostic
techniques simultaneously.

P100
POSTER
Effectiveness of EMP in long term results in tooth with abutments
Wlodzimierz Lojewski*, Anna Kurhanska-Flisykowska, Magdalena Sobieska
Department of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
The aim of this study was to evaluate the effectiveness of Emdogain in the treatment of
periodontal osseous defects around tooth with stabile prosthetic restorations. The process of
healing after periodontal treatment provided with EMP and regular open flap procedure was
observed in 12 patients seven years after the treatment. In each patient, one intrabony defect
around tooth with perio-endo syndrome or deep pocket and abutment was treated with EMP. The
periodontal condition of the participants was assessed by probing pocket depths and attachment
loss. Changes in serum concentrations of acute phase response were recorded twice at the
beginning of the experiment and after 7 years. In the statistical analyses differences were
compared using Kruskal-Wellis tests. After treatment the mediumpocket depth varied from 4,91
mm to 1,4. Medium attachment loss at baseline and 7 years post surgery varied from 3,2
-2,4 mm. Statistically significant difference between I and II examinations at P < 0,01 and P
<0,001 was confirmed. The biochemical study confirmed in blood serum a tendency to keep low
intensity of the inflammatory process after treatment. The results added a point to the usefulness
of guided tissue regeneration around stable prosthetic restorations.

P101
POSTER
A new generation of Microscope for imaging Biological Samples
Agata Czajka-Jakubowska1*, Hajfeng Chen2, Brian. H. Clarkson2, Janina Stopa1
1Department    of Conservative Dentistry and Periodontology, Poznan University of Medical Sciences, Poland
2School   of Dentistry, University of Michigan, United States
The aim of the study was to obtain images of proteins and artificial proteins (dendrimers) on nano
scale structures. The Atomic Force Microscope (AFM) is a laser imaging microscope which
allows nano scale objects to be viewed and their surface properties characterized. This is
achieved using a precisely controlled piezoelectric scanner. The tiny probe is mounted on a very
sensitive cantilever. Any minimal movement of the cantilever caused by a change of atomic force
between the probe and the sample is monitored by a laser focused on the back of cantilever.
Using a computer the deflection of the laser beam is converted into a 3-dimensional image of the
sample surface. AFM can be operated in dry and wet fields. This makes it a very useful tool to
study biological samples in solutions. By modifying the probe surface with specific chemical
groups (biomolecules) or making the probe magnetic or electrically conductive, AFM can map the
local chemical (CFM), magnetic (MFM) or electrical (EFM) properties of the sample surface with
very high resolution. AFM can be operated in different modes: contact mode and tapping mode.
Enamel crystals extracted from maturational stage developing rat incisor were reacted with 5 lL of
protein and dendrimer solutions for 2 minutes. Images were obtained in tapping mode in air using
a nanoscope IIIa Multimode AFM. Images of protein and dendrimer binding to crystals (300-600
nm) in length were obtained. AFM images of the surface of hard (enamel crystals) and soft
(proteins) will be presented. Tapping mode AFM seems to be a very promising way to generate
images of soft and delicate samples, such as proteins.

P102
POSTER
Functional impression border measuring method using a computer - aided technique
Mariusz Glapinski1*, Zdzislaw Krysinski2
1Department   of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
2Department   of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
Functional impression is taken to obtain the optimal record of the border of a future complete
prosthesis. The accuracy of this record has a great influence on the functional fit of the denture.
Methods that allow investigation of this border can show which type of recording is better then the
others. The aim of this study was to adapt a computer aided technique of visualization to a
functional impression border measuring method in edentulous mandible patients. Edentulous
patients qualified for this study. Custom trays were made for the mandible in Duracrol self-curing
acrylic resin, tested in the patient's mouth with Herbst tests, and copied using Microform technical
agar. Ten functional impressions were taken, five with Ex-3-N Gold impression wax and five with
Stomaflex condensation silicone. All the impressions were cast in dental stone (type III) and the
models were then cut with a Unimet saw into 7 mm thick sections, starting from the midline and
continuing to the retromolar area. The line of cut was perpendicular to the line of the alveolar
edge. Ten sections were obtained. Every section was scanned using a Plustec OpticPro ST 24
optical scanner with a resolution of 1000 dpi. The pictures were saved in separate files (Windows
bitmap BMP) and every picture was analyzed using Windows Paint to describe the shape and
dimensions of the groove corresponding to the border of the functional impression. This method
allows for obtaining scans which are enlarged pictures of the sectioned models. These pictures
are saved in the computer memory and can be easily analyzed by graphic and measuring
programs e.g. Microsoft Paint. The method is applicable not only for gypsum casts, but also for
other materials, when any flat surface has to be investigated. In such situations computer
analysis can be helpful.

P103
POSTER
Case report: Patient wearing broken and self-repaired mandibular complete denture
Boris Klaic1*, Damir Zarkovic1, Dubravka Knezovic-Zlataric2
1Perkovceva   Dental Polyclinic, Zagreb, Croatia (Hrvatska)
2Department   of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia (Hrvatska)
Satisfaction with removable dentures seems to have a multicausal character. Sometimes there is
a disagreement between patient's appreciation of denture quality and that assessed by a
prosthodontist. At times, patients are overly contented with their low quality dentures. The aim of
this paper was to present a case report of a patient who repaired a broken acrylic base of lower
complete denture by himself. The patient repaired the mandibular denture using chewing gum
and a thread. He wore this denture for two years. He was very satisfied, despite the fact that
retention, occlusal relationship and stability were not satisfactory from a professional standpoint.
Patient came to the Perkovceva Dental Polyclinic requesting new dentures only because he
wanted to utilize his social insurance benefits and not because he was dissatisfied with the
restoration. Correct new dentures were made and the patient received information about the
possibilities of denture repair in a dental office.

P104
POSTER
Evaluation of the shear bond strength between composites and luting cements
Andrzej Gala*, Maciej Zarow, Grzegorz Milewski
Institute of Stomatology of Collegium Medicum, Jagiellonian University, Cracow, Poland
The purpose of this study was to evaluate the influence of the composite's prepared surface on
shear bond strengthbetween composite materials and luting-cements. Two materials were used
as luting composites: Lute It (Jeneric Pentron) and Gradia Direct (GC). For fabrication of
composite inlays Gradia (GC) 24 disks of laboratory polymerized composite were used (5mm x
20mm) in accordance with manufacturer's instruction and divided into four groups: group 1
- untreated surface and connected with Gradia Direct, group 2 - treated with 50um Al2O3, then
silanized and connected with Gradia Direct, Group 3 - treated with 50um Al2O3, silanized, then
bond was applied (Jeneric Pentron) and connected with Gradia Direct, group 4 - treated with
50um Al2O3, silanized, then bond was applied and connected with Lute IT. Instron II testing
machine was used to determine shear bond strength between layers. The data were statistically
analyzed by two methods: ANOVA and Scheffe's tests. Mean shear bond strengths measured in
group 1 (298 kG) and group 2 (730 kG) were significantly lower (pT 0,05), than in group 3 (1389
kG) and in group 4 (1229 kG). Sandblasting with 50 m Al2O3 followed by silan and bond
application, is an effective method to create adhesive connection between laboratory fabricated
composite restorations and composite luting cements. Conventional hybrid composite could be
an effective material for luting procedure of composite inlays and onlays.

P105
POSTER
Porosity of four different luting dental cements
Kosovka Obradovic-Djuricic*, Vesna Medic, Slobodan Djurisic
School of Dentistry, University of Belgrade, Yugoslavia
The purpose of this study was to evaluate the porosity of four different luting cements. Materials
tested were Zinc-phosphate cement (Harvard), Zinc-polycarboxilate cement (Harvard), Glass
Ionomer cement (GC Fuji I) and resin cement (Panavia F dual cure dental adhesive system).
Cylindrical specimens were prepared using moulds with internal dimensions of 4mm high and
8mm diameter. Structure of porosity was tested by mercury-porosimeter. Carlo Elba Porosimeter
2000 was used, with the pressure range of 0.1- 200 Mpa, corresponding to pores' diameter of 7.5
to 1500 mm. Specimen density was determined by picnometer method. Size, number and total
volume ratio of the pores which existed in the specimens were determined. According to the
obtained results following conclusions can be drawn: Poly(carboxilate) cement has the greatest
porosity and specific total pore volume, while resin cement has the least of these porous structure
features. The advantage of resin cement is that all of the pores are in the meso-porosity area
with pores smaller than 20 nm. Therefore resin cement offers the best protection from oral fluids,
bacteria and bacterial toxins penetrating to the unprotected area of the tooth.

P106
POSTER
Influence of protective Al 2O3 layer on corrosion resistance of CoCr dental alloys
Dorota Rylska1, Jerzy Sokolowski2, Marcin Pers3*, Leszek Klimek1
         of Materials Science and Engineering, Technical University of Lodz, Poland
1Institute
2DentalSchool, Medical University of Lodz, Poland
3Medical University of Lodz, Poland
Corrosion of metal dentures in the oral cavity leads to their destruction and causes damaging
effect (cytotoxic, allergic). Coating the metal dentures with Al2O3 layer should decrease corrosion
and improve their biological properties. The aim of this research was to define the influence of
Al2O3 layers, coated by the sol-gel method, on corrosion resistance of basic CoCr alloys.
Research was conducted on samples, cast with CoCr dental alloys Wirobond C/Bego. Samples
for the research, disc-shaped with diameter of 9mm and thickness of 2mm, were cast using
acentrifugal method (Fornax/Bego). Six samples were prepared and polished mechanically.
Three samples were covered with Al2O3layer (layers were obtained with sol-gel method).
Samples, which were not covered with Al2O3, were used as supervisory samples. Evaluation of
alloy's corrosion resistance was made in reliance with potentiodynamic polarization method. In
order to perform this work the electrochemical techniques were used - the electrochemical
corrosion polarization test cell was used for potentiodynamic corrosion tests in a physiological
solution (0.9% NaCl). Platinum was used as the counter electrode and calomel electrode (SCE)
as the reference electrode. The working electrodes were made of examined covered and
uncovered samples of casts. To avoid contamination, the SCE electrode was connected with the
working electrode through a bridge with a Luggin capillary to reduce the ohmic drop of the
solution. The measurements were carried out by computer assisted ATLAS 9833 potentiostat-
galvanostat. Dynamic polarization curves were recorded at a potential scanning rate of 1 mV s-1
initiated at -1000 mV and scanned in the positive direction and terminated at 1500 mV. It was
proven that Al2O3 layers decreased corrosion of CoCr alloys.

P107
POSTER
Influence of pH on corrosion of dental alloys
Marek Baraniak1*, Aleksander Ciszewski1, Magdalena Urbanek-Brychczynska2
1Institute   of Chemistry and Applied Electrochemistry, Poznan University of Technology, Poland
2Department      of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
Corrosion resistance of alloys is one of the most important parameters enticing to use these
materials in human body. Corrosion processes depend on the specific characteristics of different
oral environments. The specific character of oral environments causes problems with easy
interpretation of corrosion behaviour of dental alloys and in some patients causes allergies or
even disease. The corrosion behaviour of selected alloys belongs to the four most important
groups of biomaterial uses in dentistry: chromium-cobalt alloys, chromium-nickel alloys, noble
metals alloys and titanium were checked in 2 solutions with different pH. An electrochemical
characterization of alloys was performed by potentiostatic and potentiodynamic methods, i.e. the
open circuit potential (OCP), the corrosion potential (ECORR), corrosion current (iCORR), and
corrosion resistance (RCORR). Solutions of different pH perpetrate using popular medicine:
vitamin C and Manti Forte. It was found that OCP [V] increase in order OCPvit. C <
OCPMantiForte. Difference of OCP value in these 2 solutions were very significant. The highest
differences were observed for Bioheragold C. The smallest value OCPvit. C - OCPMantiForte
was observed for Remanium G-Weich, ICORR for vitamin C solution usually were higher than for
Manti Forte solution. In the cases of iCORR of Spall WT-52, Osteoplant, and G-Weich opposite
trend was observed. Unexpectedly high iCORR was the measurement in vitamin C for
Bioheragold C solution and Amalcap Plus 2 and in Manti Forte solution for Spall WT 52.
Presented study shows that corrosion problems in such volatile environment that exists in oral
cavity must be researched further. A wide array of foods, drinks, and medicine currently available
may impact in significant ways on the intensity of corrosion; even on noble alloys.

P108
POSTER
Corrosion investigations of some dental alloys in selected solutions
Magdalena Urbanek-Brychczynska1*, Aleksander Ciszewski2, Marek Baraniak2
1Department      of Oral Rehabilitation, Poznan University of Medical Sciences, Poland
2Institute   of Chemistry and Applied Electrochemistry, Poznan University of Technology, Poland
The most important properties of dental alloys are their biocompatibility, corrosion resistance,
mechanical features and ease of workability. The chemical composition and the microstructure
have a great influence on their corrosive behaviour like surface roughness, the degree of
oxidation, the pH. The aim of this study was to evaluate and compare in vitro, the galvanic
corrosion behavior of selected alloys in few chosen solutions. An electrochemical characterization
of the alloys was performed by potentiostatic and potentiodynamic methods, i.e. the open circuit
potential (OCP), the corrosion potential (ECORR), corrosion current (iCORR), and corrosion
resistance (RCORR) in selected solution in two groups: typical drinks, typical agents for hygiene
of the oral cavity and prosthetic elements. It was found that OCP [V] increased in chromium-
cobalt and chromium-nickel alloys in order OCPTee < OCPBols< OCPCoca Cola, with few
exceptions. In second group of solution OCP [V] of alloys increased in order OCPCorega Tabs <
OCPElmex< OCPPearl drops. ECORR for chromium-cobalt alloys increased in sequence
ECORR tee< ECORR Bols < ECORR Coca Cola but few exceptions were also found. Potentials
ECORR for chromium-nickel increased ECORR Bols< ECORR tee < ECORR Coca Cola. Much
less clear situations exist in agents for hygiene of oral cavity and prosthetic elements. Only
slightly tendency ECORR Elmex< ECORR Corega Tabs < ECORR Pearl drops may be
suggested for both types of alloys. ICORR in tea solution for chromium-nickel is higher than in
Coca-cola and Bols solutions. ICORR for chromium-cobalt alloys are quite close in all 3 solutions,
with exception alloy BiosilF in Bols. In second group of solutions high value iCORR was observed
for BiosilF, and for Remanium 800 for chromium-cobalt alloys. Presented investigations show that
measurements made only in artificial saliva even with changing pH don't solve all potential
problems with corrosion in real systems.

P109
POSTER
The microstructure and electrochemical activity of selected dental alloys
Krystian Szuminski1*, Wieslaw Hedzelek1, Ludwik Domka2, Maciej Kozak3
1Department of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Technology Centre of Faculty of Chemistry, Adam Mickiewicz University of Poznan, Poland
3Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University of Poznan, Poland
The success of prosthetic treatment is determined, besides diagnostics, therapy planning and its
realization, by proper laboratory procedures. One of the fundamental work stages of
manufacturing a removable partial denture is electropolishing. The aim of the study was to
evaluate the microstructure and galvanic activity of selected non-precious dental alloys, which
underwent electropolishing. The objects of the study were three chrom-cobalt-molibdenic alloys:
Wironit from the BEGO-concern, Remanium GM 800 from the Dentaurum-concern Biosil F from
the Degudent-concern. The samples, 30 by 12 and 1,52 mm thick were cast from the alloys, and
then electropolished for 5, 15 and 30 minutes in a BEGO machine - model Eltropol SL. The
surface of the studied samples was evaluated by means of roentgenological technique of
polycrystalline difractmetry (XRD) with the use of a modified difractmeter HYG-4 with electronic
registration. The evaluation of the electrogalvanic activity of alloys in the artificial saliva
environment with pH-value between 3-11 included the measurement of electrogalvanic potentials
in relation to calomelic zero-electrode. During the difractical measurement all the samples were
oriented to the same surface in the direction of the reontgenological ray. This was done to
eliminate possible influence of the texture on the difractical view. The result of electropolishing
was an increase in the intensity of the examined dyfractical maximums and the appearance of
new difractical maximums at higher values of 2 angle. This process could have been caused by
the dissolution of the refuse layer from the surface during electropolishing. The time of
electropolishing had a significant influence on the microstructure and lead to its optimal
smoothing. Extending the polishing time, brought about a decrease in the electrogalvanic activity
of the chrom-cobalitc alloys.

P110
POSTER
Erosive toothwear and salivary differences between in patients with gastro-esophageal
reflux disease (GERD)
and bulimia nervosa
Elzbieta Paszynska*, Justyna Jurga-Krokowicz, Honorata Limanowska-Shaw
Department of Biomaterials and Experimental Dentistry, Poznan University of Medical Sciences, Poland
Gastric disorders such as GERD are interesting from the dental point of view because of the
regurgitated acidic fluid which may cause oral tissue changes such as dental erosion. Patients
whose teeth have been damaged as a consequence of vomiting and gastro-esophageal reflux
disorders visit their dental surgeon quite frequently. The aims of this study were to evaluate the
prevalence of erosive toothwear in subjects with GERD and to investigate the levels of
selected components in their saliva, when compared with both a group of patients with bulimia
nervosa and a control group of normal subjects. 20 subjects who met the criteria for GERD
formed Group A. 33 patients who gave a history of vomiting - type bulimia nervosa formed Group
B and 50 healthy subjects, matched for sex, age and medical history, formed the control Group C.
In all subjects the severity of dental erosion was determined according to the Smith and
Knight Wear Index. The levels of pH and bicarbonates in resting and stimulated whole saliva
were determined by a spectrophotometric (340 nm UV) method using an ABL 520 Radiometer
(Medical A/S, Denmark) and salivary flow rates wre measured. Kruskall Wallis and one way
ANOVA and Rank and Dunn pairwise multiple comparisons were used for the statistical analyses
(pH< 0.05). As expected, the greatest prevalence of dental erosion was found in Group B
(23.31%). Salivary flow rates, pH and bicarbonate levels in mixed saliva were significantly higher
in the control Group C (0.61ml/min; 6.75; 5.06mmol/l) than in Group A (0.56ml/min; 6.94;
6.14mmol/l) and Group B (0.28ml/min; 6.45; 4.4mmol/l), respectively. These findings suggest that
the levels of some salivary components, particulary pH, could contribute to the degree of erosion
seen in bulimic patients and those suffering from GERD. This study was supported by State
Committee for Scientific Research grant 2 PO5EO9826.

P111
POSTER
Numerical evaluation of screw loosening problems in implant dentistry using three
dimensional models
Wieslaw Hedzelek1*, Rafal Zagalak2, Tomasz Lodygowski3, Marcin Wierszycki3
1Department    of Prosthetic Dentistry, Poznan University of Medical Sciences, Poland
2Foundation    of Poznan University of Medical Sciences, Poland
3Institute of Structural Engineering, Poznan University of Technology, Poland
Finite element analysis plays a key role in solving engineering problems in many fields of science
and industry and can be successfully applied also in simulation of biomechanical systems. Both
clinical cases reports and experimental researches prove that significant problem in long-term
patients observation is screws loosening. Although it is reversible very serious prognostic sign
can be repetitive screw loosening episodes which can lead to component fractures. The goal of
the study was evaluation of mechanical conditions influencing the risk of abutment screw
loosening in two-stage dental implant. The full simulation of implant mechanical behaviour have
been carried out with the finite element method program ABAQUS/Standard. For the full
simulation of implant structure behaviour, a three dimensional model is necessary. This model,
which includes a spiral thread, enables taking into consideration a few important aspects such
as full simulation of kinematics of the implant, describing the multiaxial state of stress and, the
most important, the possibility of simulation of screw loosing. For simulations performing authors
used OSTEOPLANT dental implants (Foundation of Poznan University of Medical Sciences) - a
common example of internal hex connection. Results obtained from numerical analysis clearly
describe step by step mechanism of screw loosening and prove that the main factors which
determine above problem is friction, preload and type of connection.

				
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posted:11/11/2011
language:Polish
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