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					PREVETION OF DENTAL CARIES
              INTRODUCTION
Dental caries is defined as a progressive irreversible
  microbial disease affecting the hard parts of tooth
  exposed to the oral environment, resulting in
  demineralization of the inorganic constituents and
  dissolution of the organic constituent, thereby leading to
  a cavity formation.
• The word caries derived from Latin meaning ‘rot’ or
  decay
• Similar to the Greek word ‘ker’ meaning death
• The relationship between diet and dental caries
  Bacterial enzymes + fermentable carbohydrates = acid,
  Acid + enamel = dental caries
 CURRENT TRENDS IN CARIES
       INCIDENCE
• In developed countries, caries prevalence
  declined in last decade, causes are
  multifactorial. Eg: communal water
  fluoridation.
• In developing countries increase in caries
  prevalence, cause is increased use of
  refined carbohydrates.
  CARIES SUSCEPTIBILITY JAW
         QUADRANTS
• Bilateral distribution between the right and
  left quadrant of both maxillary and
  mandibular arches.
• Maxillary teeth more susceptible than
  mandibular arch
   relate to gravity and saliva, with its
  buffering action, would tends to drain from
  upper teeth and collect around lower teeth.
     CARIES SUSCEPTIBILITY OF
         INDIVIDUAL TEETH
•   Upper and lower first molar                       95%
•   Upper and lower second molar                      75%
•   Upper second bicuspid                             45%
•   Upper first bicuspid                              35%
•   Lower second bicuspid                             35%
•   Upper central and lateral incisor                 30%
•   Upper cuspids and lower first bicuspid            10%
•   Lower central and lateral incisor                 3%
•   Lower cuspids                                3%
•   Teeth farthest back in the mouth are more frequently carious.
•   Caries susceptibility of individual tooth surface
    occlusal > mesial > buccal > lingual
     ECONOMIC IMPLICATION OF
         DENTAL CARIES
    Factors changing the economic implication of
    treatment of dental caries :-
•   Economic status of population
•   Increasing educational status
•   Growing number of dental graduates
•   Insurance programs
•   Commercial pressure
•   Governmental influences
   CLASSIFICATION OF DENTAL
            CARIES
A) Black’s classification
CLASS I – cavities on the occlusal surface of premolars
  and molars, on the occlusal two-third of the facial and
  lingual surface of molars, on lingual surface of maxillary
  incisors.
CLASS II – cavities on the proximal surface of posterior
  teeth
CLASS III - cavities on the proximal surface of anterior
  teeth that do not include the incisal angle
CLASS IV – cavities on the proximal surface of anterior
  teeth that include the incisal angle
CLASS V – cavities on the gingival third of the facial or
  lingual surface of all teeth
CLASS VI - cavities on the incisal edge of anterior teeth or
  occlusal cusp height of posterior teeth
B[1] According to location on individual
  teeth
- Pit and fissure caries
- Smooth surface caries
B[2] According to the rapidity of the process
- Acute dental caries
- Chronic dental caries
B[3]
- Primary caries (virgin)
- Secondary caries (recurrent)
PIT AND FISSURE CARIES
- Pits and fissures with high steep walls &
  narrow base  retention of food, debris,
  micro organisms  fermentation  acid
  production
- Caries appear brown/ black, feel soft
- Enamel bordering  opaque bluish
  white
- Large carious lesion with a tiny point of
  opening
SMOOTH SURFACE CARIES
- Preceded by formation of microbial/ dental
  plaque
- Begins just below contact point and appear in
  early stages as faint white opacity of enamel
  (chalky spot)  slightly roughened 
  surrounding enamel bluish white as caries
  penetrate enamel
- Cervical carious lesion crescent shaped
  cavity (extend from areas opposite to the
  gingival crest occlusally to convexity of tooth
  surface)
ACUTE DENTAL CARIES
- Rapid clinical course & early pulp
  involvement
- Process rapid  little time for deposition of
  sec. dentin. Dentin stained a light yellow
- Rampant caries, affecting deciduous dentition
   nursing bottle caries
- Commonly 4 maxillary incisors followed by
  first molar and then cuspids
- Absence of caries in mandibular incisors
  distinguished from ordinary rampant caries
• CHRONIC DENTAL CARIES
- Progress slowly and leads to involve pulp
  much later
- Sufficient time for both sclerosis deposition of
  sec. dentin
- Carious dentin stained deep brown.
- cavity shallow with min. softening of dentin
- Pain and undermining of enamel not a
  common feature
RECURRENT CARIES
- Occurs in immediate vicinity of restoration
- Poor adaptation of filling material
ARRESTED CARIES
- Static or stationary caries
- Exclusively in caries of occlusal surface
- Large open cavity and lack of food
  retention
- Superficially retained and decalcified
  dentin gradually burnished until it takes
  a brown stain, polished appearance and
  is hard  EBURNATION OF DENTIN
- Caries on proximal surface of teeth 
  adjacent approx. tooth extracted
         THEORIES OF CARIES
             FORMATION
• Legend of the worm theory
• Endogenous theories
    Humoral theory
    Vital theory
• Exogenous theory
    Chemical (acid) theory
    Parasitic (septic) theory
    Miller’s chemicoparasitic theory – Acidogenic theory
    Proteolysis theory
    Proteolysis chelation theory
    Sucrose – chelation theory
• Other theories
    Auto immune theory
    Sulfatase theory
    ETIOLOGIC FACTORS IN
       DENTAL CARIES

•   Dental caries is a multifactorial
    disease in which there is an interplay
    of 3 principle factors.
       I. The host ( teeth, saliva etc.)
       II. Micro flora
       III. Substrate (diet)
•   In addition the fourth factor, time
    must be considered.
         I. HOST FACTORS
Tooth
• Composition
• Morphologic characteristics
• Position
Composition of tooth
Enamel:-
- Inorganic : 96%
- Organic + water : 4%
Dentin:-
- Organic matter +water :35%
- Inorganic :65%
Cementum:-
- Inorganic : 45-50%
- Organic +water : 50- 55%
Morphological characteristics of the tooth
• Feature predisposed to the development of
  dental caries is presence of deep narrow
  occlusal fissure/ buccal and lingual pits

Tooth position
• Which are malaligned, out of position, rotated
  or otherwise not normally situated, may be
  difficult to clean and tend to favor the
  accumulation of food and debris which
  subsequently lead to dental caries
Saliva
• Composition
• PH
• Quantity
• Viscosity
• Antibacterial factors
Composition of saliva
Inorganic:-
       Positive ions:- Ca, Mg, K,
       Negative ions:- CO2, Cl, F, PO4,
  thiocynate
Organic:-
       Carbohydrates : glucose
       Lipids : cholesterol, lecithin
       Nitrogen : non- protein ammonia,
  nitrites & amino acids
                  protein  globulin, mucin, total
  protein
       Miscellaneous : peroxides
       Enzymes : carbohydrases, proteases,
  oxidases
PH of saliva
• Determined by bicarbonate concentration
• PH increases with flow rate, normal PH 7.8
• Sialin is an argenine peptide described PH
  rise factor, present in saliva
Quantity of saliva
• Normal quantity 700-800 ml per day
• In case of salivary gland aplasia and
  xerostomia in which salivary flow may entirely
  lacking, resulting in rampant dental caries
Viscosity of saliva
• Thick, mucinous saliva increases the dental
  caries
Antibacterial properties of saliva
Lactoperoxidase
• They participate in killing of microorganisms
  by catalyzing the H2O2 mediated oxidation of
  a variety of substances in the microbes
• Utilizing thiocynate ions in saliva peroxidation
  generate highly reactive chemical compound
  that bond and inactivate general intracellular
  microbial enzyme system, as well as
  microbial surface compound.
Lysozyme
• Small, highly positive enzyme that catalyze
  the degradation of negatively charged
  peptidoglycan matrix of microbial cell wall
Lactoferin
• Fe binding basic protein found in saliva with mol. wt.
  near 80,000.
• Tends to bind & link the amount of the free Fe which
  is essential for microbial growth
IgA
• Immunoglobulin in saliva
• Inhibit adherence and prevent colonization of
  microbial on tooth and mucosal surfaces
Other salivary components with protective function
Proline rich protein
• Mucus and glycoprotein
• Because of their high proline content, there are rigid
  collagen like molecules designed to form a pseudo
  membranous layer in the hard and soft oral surfaces
  as well as on the oral flora.
Aromatic rich protein
• Statherin
• It causes remineralization
Other host factors
Age
• Dental caries decreases as age
  increases
• Root caries are common in elders
• Gingival recession  cemental
  exposure (improper brushing)
Socioeconomic status
• High  low chance
• Low  more chance
           II. MICROFLORA
• Strep. mutans  early carious lesions of enamel
• Lactobacilli  dentinal caries
• Actinomyces  root caries
Role of microorganisms in dental caries
• Prerequisite for dental caries initiation
• A single type of microbe is capable of
  inducing dental caries
• Ability to produce acid  prerequisite
  for caries induction
• Streptococcus strains are capable of
  inducing caries
• Organisms vary greatly in their ability to
  induce caries
Role of dental plaque
• soft, non mineralized, bacterial
  deposit which forms on a teeth that
  are not adequately cleaned
• Complex metabolically interconned
  highly organized bacteria/
  ecosystem
• Important component of dental
  plaque is acquired pellicle  just
  prior or concomitantly with bacterial
  colonization and may facilitate
  plaque formation
• Microbial in dental plaque
   streptococci
   actinomycetes
   veillonella
• Strep. mutans  chief etiological
  agent of dental caries
                       III. DIET
• Increase in carbohydrate increase carious activity
• Risk of caries is greater if the sugar is consumed in a
  form that will be retained on the surface of the teeth
• Risk of sugar increasing caries activity if it is consumed
  between meals
• Increasing caries activity varies widely between
  individuals
• Upon withdrawal of the sugar rich foods the increased
  caries activity rapidly disappears
• Carious lesion may continue to appear desperate to
  avoidance of refined sugar and maximum restriction on
  natural sugars dietary carbohydrates
• High concentration sugar in solution and its prolonged
  retention on the tooth surface leads to increased caries
  activity
• Clearance time of the sugar correlates closely with
  caries activity
    THE CARIES PROCESS
• Caries of enamel
       smooth surface caries
       pit and fissure caries
• Caries of dentin
• Caries of cementum
 SMOOTH SURFACE CARIES
• Earliest manifestation is the appearance of an
  area of decalcification, beneath dental plaque
  with a smooth chalky white area
• Loss of interprismatic substance with increase in
  prominence and roughening of ends of enamel
  rods
• Accentuation of incremental striae of retzius
• As this process advances and involves deeper
  layer of enamel it forms a cone shaped lesion
  with apex towards DEJ and base towards
  surface of teeth
   PIT AND FISSURE CARIES
• Because pit and fissure provides more depth 
   increased food stagnation with bacterial decomposition
• Here caries follow direction of enamel rods and forms a
   cone shaped lesion with apex at outer surface and base
   towards DEJ
Different zones present in lesion are
Zone 1: translucent zone 
   Advancing front of enamel lesion, not always present
Zone 2: dark zone 
   Referred as positive zone formed as a result of
   demineralization
Zone 3: body of lesion 
   Area of greatest mineralization
Zone 4: surface zone 
   Appears relatively unaffected
           CARIES OF DENTIN
• Initial penetration of dentin by caries may result in
  dentinal sclerosis
• This is a reaction of vital dentinal tubules and a vital
  pulp, in which results in calcification of dentinal tubules,
  that tend to seal them off against further penetration by
  microorganisms
• The different zones which are present in carious dentin
  are (beginning pulpally at advancing edge of lesion)
Zone 1 : zone of fatty degeneration of Tome’s fibres
Zone 2 : zone of degeneration
Zone 3 : zone of decalcification
Zone 4 : zone of bacterial invasion of decalcified but intact
  dentin
Zone 5 : zone of decomposed dentin
           ROOT CARIES
• Defined as soft progressive lesion that is
  found anywhere on root surface that has
  lost connective tissue attachment and
  exposed to oral environment
• Microorganisms involved in root caries are
  filamentous
• Microorganisms invade cementum, along
  sharpey’s fibres
        INDICES USED TO
     ASSESSMENT OF DENTAL
             CARIES
1.   DMFT index
2.   DMFS index
3.   DEF index
4.   Stone’s index
5.   Caries severity index

Diagnosis of caries
1. Identification of subsurface demineralization
    (inspection/ palpation, radiographs)
2. Bacterial testing (caries activity testing)
3. Assessment of environment conditions like salivary
    PH, flow and buffering
METHODS OF CARIES CONTROL
•  There are various levels for prevention of
   dental caries
    these include
1. Primary prevention
2. Secondary prevention
3. Tertiary prevention
levels of    Primary prevention                           Secondary             Tertiary prevention
prevention                                                prevention
Preventive   Health promotion        Specific             Early diagnosis       Disability       Rehabilitation
services                             protection           and prompt            limitation
                                                          treatment
Services     Diet planning,          Appropriate use      Self examination      Utilization of
provided     demand for              of fluoride,         and referral,         dental
by the       preventive              ingestion of         utilization of        services         Utilization of
individual   services, periodic      fluoridated water,   dental services                        dental services
             visit to dental         use of fluoridated
             office                  dentifrices
Services     Dental health           Comm. or school      Periodic              provision of     provision of
provided     education               water                screening and         dental           dental services
by           programs,               fluoridation,        referral, provision   services
community    promotion of lobby      school fluoride      of dental
             efforts                 mouth rinse          services
                                     program, school
                                     fluoride tablet
                                     program, school
                                     sealant program
Services     Patient education,      Topical              Complete exam,        Complex          Removable and
provided     plaque control          application of       prompt treatment      restorative      fixed
by the       program, diet           fluoride,            of incipient          dentistry        prosthodontic
dental       counseling, recall,     supplements/         lesions,                               minor tooth
profession   reinforcement,          rinse preparation,   preventive resin                       movement,
             caries activity tests   pit and fissure      restoration, pulp                      implants
                                     sealants             capping
  METHODS TO CONTROL CARIES
1. Chemical measures
2. Nutritional measures
3. Mechanical measures
    1. CHEMICAL MEASURES
   A vast number of chemical substances have been
   proposed for the purpose of controlling dental caries
Ideal properties:
• It should be safe for intraoral use
• Must be able to penetrate dense microbial plaque
• Agent used for topical application should not be
   systematically toxic if swallowed accidentally
• Should not produce local tissue irritation
• Should be rapidly bactericidal as contact time is less
• Should possess degree of specificity
• Should be destroyed or inactivated by GIT
• Should have an acceptable taste
• Medically important antibiotics should not be used
Chemical measures include:
I.   Substances which alter tooth surface or
     tooth structure
II. Substances which interfere with
     carbohydrate degradation through
     enzymatic alteration
III. Substances which interfere with bacterial
     growth and metabolism
    I. SUBSTANCES WHICH ALTER
       TOOTH SURFACE/ TOOTH
            STRUCTURE
•    Chemicals falling into this categories
     include
    a.   Fluorides
    b.   Iodides
    c.   Bisbiguanides
    d.   Silver nitrates
    e.   Zinc chloride and potassium ferrocyanates
Fluoride
• Most widely used and promising chemical in
   this category
• Fluorides have been administrated
   principally in two ways
    a. Systemic application
       eg:- School water fluoridation, community water
       fluoridation, milk fluoridation, self fluoridation
    b. Topical application
       eg:- Sodium fluoride, aciduated phosphate
       fluoride, stannous fluoride
•    A fluoride concentration of 1 ppm in drinking
     water is associated with a marked decrease
     in dental caries
• Other methods of using fluorides are
   As dietary supplementation of fluoride
   Fluoride dentifrices
   Fluoride in mouth washes/ rinses
   Fluoride incorporated in chewing gums and dental
    floss
• Rinses for caries reduction
 Rinse     Concentratio   PH    Application
             n
 Aqueous   0.2%           7     Once a wk/
   NaF                            once
                                  every 2
                                  wk
 Aqueous   0.5%           7     Once daily
   NaF

 Aqueous   0.02%`         4     Once daily
   APF
    The effect of fluoride influencing its
    anticaries actions are:-
•   Interference in enzymatic process of
    bacteria
•   Direct bactericidal action
•   Reduction of plaque formation
•   Enhancement of enamel
    remineralization
•   Stimulation of formation of large
    appetite crystal
•   Lowers the solubility of enamel
Iodine
•   Used as a antibactericidal mouth
    rinses
•   Kills microorganisms immediately
•   Disadvantages : metallic taste, stain
    metallic or composite restorations
Bisbiguanides
•   The two most common commercially
      available bisbiguanides are:
   a) Chlorohexidine
   b) Alexidine
•   These are potential anticaries agents
•   They are bactericidal
•   Have both hydrophobic and
    hydrophilic constituents and possess a
    net +ve charge – adsorbs –vely
    charged membrane surface and
    damage to the membrane by breaking
    permeability barrier
•    Disadvantages
    1.   Stains teeth and dorsum of tongue
    2.   Evidence of bacterial resistance
    3.   Bitter taste
    4.   Mucosal irritation and desquamation
    5.   Allergic reaction

         Silver nitrate, zinc chloride and
         potassium ferrocyante
         - seal off the enamel caries invasion
         pathway by getting impregnated to the
         enamel
     II. SUBSTANCES WHICH INTERFERE
    WITH CARBOHYDRATE DEGRADATION
    THROUGH ENZYMATIC ALTERATIONS
•     Includes:-
     1. Vitamin K
     2. Sarcoside
     Vitamin K
-     Vit. K was found to prevent acid formation in
      incubated mixtures of glucose and saliva
     Sarcoside
-     Sodium-N-lauryl sarcosinate & sodium
      dehydroacetate were promising enzyme
      inhibitors or antienzymes. They have the ability
      to reduce the solubility of powdered enamel
  III. SUBSTANCES WHICH INTERFERE
      WITH BACTERIAL GROWTH AND
               METABOLISM
Includes:-
• Urea and ammonium compounds
• Chlorophyll
• Nitrofurans
• Antibiotics
• Caries vaccines
Urea and ammonium compounds
• Potential anticariogenic agents.
• Urea  degradation by urease  ammonium
   neutralize acids
• They are cationic antiseptic and surface
  active agents
• More active against GPB.
• Mechanism of action:- +vely charged
  molecules reacts with –vely charged cell
  membrane phophates and thereby disrupts
  the cell wall structure microorganisms.
  Eg:- benzathonium chloride, benzalleonium
  chloride, cetylpyredinium chloride
Chlorophyll
• Water soluble form of chlorophyll is capable
  of preventing or reducing the PH fall in
  carbohydrate
• Saliva mixture invitro chlorophyll is
  bactriostatic
Nitrofurans
• These compounds have been found to exert
  bactriostatic and bactriocidal action
• Act on both aerobic and anaerobic
  microorganisms
• Eg:- furacin 0.2% cream
Antibiotics
• Penicillin:- as an anticariogenic compound, act on cell
  wall synthesis
  disadvantage: resistance
• Erythromycin:- act on bacterial protein synthesis
  Disadvantage: diarrhoea and resistance
• Kanamycin:- act on bacterial protein synthesis. It
  reduced S. Mutans and S. Sanguis population in
  plaque
  Disadvantage: nephrotoxicity and ototoxicity
• Others:- spiramycin, tetrcycline, tyrothricin,
  vancomycin
Caries vaccine
• Caries vaccine dates back to a period, when
  lactobacilli were thought to be of paramount of
  importance. Oral administration of S. Mutan vaccine
  leads to accelerated clearance S. mutans from
  mouth.
   NUTRITIONAL MEASURES
  The chief nutritional
  measures advocated for
  the control of dental
  caries is restriction of
  refined carbohydrate
  intake.

Other measures include
- Avoiding sugar that
  retains of teeth surface
- Avoiding sugar in
  between meals
- Eating of phosphated
  diets
Phosphated diet
Phosphates are anticariogenic sodiummeta phosphate appear to
    be most effective. Phosphate exhibit their cariogenic action
    via local factors like:-
1.  Reduction of enamel solubility
2.  Buffering effect in neutralizing salivary plaque
3.  Rendering fats, carbohydrates and proteins which are less
    cariogenic
4.  Interference with enzymatic process on enamel surface to
    increase host resistance
5.  Decrease in bacterial adhesion
6.  Interference with enzymatic process on enamel surface to
    increase host resistance
7.  Interference with synthesis of extra cellular polysaccharide
    formation
8.  Maintenance or increase of plaque calcium and phosphorous
    level.
•   Other inhibitors like pyridoxine, fat, tannic acid, xanthines,
    constituents of cocoa butter are believed to have caries
    protective factors. Nutritional or dietary means of caries
    control is impossible to achieve on basis of mass prevention
    program
     MECHANICAL MEASURES
•    This refers to procedures specifically
     designed for and aimed at removal of
     plaque from tooth surface methods for
     cleaning tooth mechanically are:
1.   Prophylaxis by dentist
2.   Tooth brushing
3.   Mouth rinsing
4.   Use of dental floss or tooth picks
5.   Incorporation of detergents foods in
     diet
6.   Pit and fissure sealants
Dental prophylaxis
• Careful polishing of
  roughened smooth surface
  and correction of faulty
  restoration decreases the
  formation of bacterial plaque
  and there by reducing the
  development of new carious
  lesion
Tooth brushing
Types of tooth brushing
- Manual
- Powered
- Sonic and ultrasonic
- Ionic
ADA specification for a tooth
  brush
- 1- 1.25 inches length
- 5/16 – 3/8 inches in width
- 2 – 4 rows of bristles
- 5-12 tufts per row
Mouth rinsing
• Use of mouth wash for the benefit of its action in
    loosening food debris from teeth has been suggested to
    be of value as caries control measures.
Dental floss
• Dental flossing is effective in removing plaque and
    dislodge the irritating matter that is real source of
    disease.
• Used in type I gingival embrasures
It is available in:
- Multifilament – twisted / non twisted
- Bounded / unbounded
- Thick / thin
- Waxed / non waxed
Oral irrigators
- Use of flushing devices
- Irrigation devices composed of a built in pump and a
    reservoir
- It can also be used to deliver antimicrobial agents
Detergent foods
• Fibrous food in diet prevent lodging of food in pit and
   fissure and acts as detergent
Chewing gum
• Chewing gum tend to prevent caries by mechanical
   cleaning action
Pit and fissure sealants
• A sealant is a dental resin that is firmly bounded to
   enamel surface and isolates pit and fissure from
   caries producing conditions in oral environment
• Types:
   1st generation – ultraviolet light activated
   2nd generation – chemical activated
   3rd generation – visible light activated
   4th generation – fluoride containing
• Examples of pit and fissure sealants
    alphadent
    helioseal F
    helioseal
    Seal – rite
    baritone L3
    concise white sealant
    concise light cure white seal
          CONCLUSION
    Dental caries is an irreversible process.
It is a disease of modern man and its
manifestation persist throughout life. There
are various methods of control and
prevention of disease. It is always better to
prevent disease. Once occurred it has to
be controlled as it has dangerous sequale.
THANK YOU

				
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