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Headgear Appliances

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Headgear Appliances Powered By Docstoc
					                                             Ideal Orthodontic Treatment
                                                      Sequence
                                           All patients should be referred no later than age 7 for

Headgear Appliances                        an orthodontic consult
                                           At that visit, orthodontist assesses if there are any
                                           issues that must be addressed prior to eruption of all
                                           of the adult dentition
     Natalie A. Capan, D.M.D.              If so, patient is receives comprehensive orthodontic
        580 Sylvan Avenue, Suite 1M        treatment
     Englewood Cliffs, New Jersey 07632        Phase I – Typically between ages 7-11
               (201)569-9055                   Phase II – Begins after eruption of most of adult
        www.CapanOrthodontics.com              dentition
             CapanOrtho@nj.rr.com




 A Common Misconception


Dentofacial Orthopedics
   and Orthodontics




                                          Importance of Proper Planning of
     What is Headgear?
                                                 Phased Treatment
                                           Phase I and Phase II are planned together to work in
Orthopedic appliance that                  accordance with each other
                                           Patient’s case must be treatment planned and diagnosed
allows orthodontists to                    completely before the start of Phase I to ensure proper design of
                                           any Phase I appliance
control growth of facial                   Just like headgear, all of the phase I appliances require proper
structures                                 design in order to be beneficial to the patient
                                           Proper diagnosis requires
Various designs                               Panoramic Radiograph
                                              Cephalometric Radiograph
Used with growing                             Models
                                              Photos
patients                                      Full orthodontic examination




                                                                                                               1
Typical Phase I Treatments                            Types of Headgear
                                           Class II Correction (excess
Sagittal Corrections (Anteroposterior)     growth of maxilla/deficient
   Headgear                                growth of mandible)
   Functional appliances
                                             Cervical Headgear
   Active retainers
                                             High Pull Headgear
Transverse Corrections
                                             Combination
   Expanders
Vertical Corrections                       Class III Correction (deficient
   Bite plane retainers                    growth of maxilla/excess growth
Spacing Corrections                        of maxilla)
   Space maintainers                         Reverse Pull Headgear
   Nance appliances                          Chin Cup




                                           Differential Diagnosis of Class II
         Phase II Treatment
                                                   Skeletal Pattern
                                            Anteroposterior
Fixed bracketed appliances on maxillary         Prognathic maxilla/retrognathic
                                                mandible/combination of both
and mandibular teeth                            Superimposed on the skeletal
                                                problems are the maxillary and
If phase I is conducted properly, phase         mandibular dentition which may
                                                be protrusive or retrusive and
II treatment can often minimize need for        proclined or retroclined
premolar extractions and excessively        Vertical
                                                facial excess or deficiency must
long treatment times                            be considered
                                            Transverse
                                                Maxillary or mandibular
                                                constriction




      Angle’s Classification of              Treatment Options for Class II
      Malocclusions - Review                         Correction
Class I – Normal molar                      Restrict maxillary growth
relationship (neutrocclusion)                  Headgear
    The mesiobuccal cusp of                    Must be in growing patient
    maxillary molar in line                 Retract maxillary dentition
    with the buccal groove of                  Limited potential
    the mandibular molar                    Camouflage by extraction of upper
Class II – Lower molar distal               premolars
to upper molar (distocclusion)              Advance the Mandible
Class III – Lower molar                        Alter growth with a functional
mesial to upper molar                          appliance
(mesiocclusion)                                Surgery
                                            Advance Mandibular Dentition




                                                                                   2
   Headgear Components                             Cervical Headgear
Force applied                             Extraoral anchorage is
                                          at the back of the neck
to first molars                           Advantages
that are                                      Easy to wear
banded via a                                  Not as visually
                                              apparent
facebow with a                            Disadvantages
headcap or a                                  Causes extrusion of
neckstrap for                                 the upper first molars
                                              which can cause an
anchorage                                     open bite




            Facebow                               High Pull Headgear
Outer bow –                               Anchorage at the back
                                          of the head
different lengths
                                          Advantages
Inner bow – sized,                           Will not extrude upper
                                             molars
connects to the
                                          Disadvantages
maxillary molars                             More hardware for
                                             patients
                                             More difficult to achieve
                                             posterior forces on the
                                             maxilla




           Headstraps                             High Pull Headgear
 Cervical Type       High Pull Headgear   To produce no
                                          tipping of the molar,
                                          the force of the
                                          headgear should go
                                          through the root
                                          trifurcation




                                                                         3
Optimal Usage of Headgear           Effects of Less Force
Worn regularly for 10-        May produce dental changes
12 hours per day              and not skeletal changes
Normally, orthodontists
suggest 14 hours/day
Growth hormone
released in the early
evening
Ideal to place headgear
after dinner not before
bedtime




       Magnitude of Force       Side Effects of Headgear
Ideal amount of force is      Unwanted extrusion
350-450 gm per side           forces on maxillary
(12 to 16 ounces)             molars (typically found
                              with cervical headgear)
Most movement                 will cause the mandible
through intermittent          to move inferiorly and
forces                        posteriorly
Hyalinized bone around        Negates Class II
molars                        correction
Mobility of Molars            Can also be caused
normal                        with distal tipping of
                              molars




 Effects of Excessive Force         Center of Resistance
Greater than 1000 gm total    Studies show that the
                              center of resistance of
Traumatic to the teeth and    the maxilla is above the
supporting structures         roots of the premolar
                              teeth
                              Forces must be directed
                              perfectly through this
                              point to effectively
                              restrain maxilla without
                              tipping it




                                                            4
Clinical Procedures in Headgear
                                                            The Outer Bow adjustment
            Placement
Separators make                                            The outer bow should rest several
room for band                                              millimeters from the cheeks
placement                                                  The bow should be cut to proper
Molar bands placed                                         length and inclination
on maxillary first
molars fit with
buccal tubes
Bands are fitted and
cemented




           Facebow Fitting                                 Class II Presentation – Frontal View
Preformed facebows selected and modified to fit the
arch form of the patient                                   Protrusion of the
Inner bow should fit closely to the arch form              upper incisors
Omega loops/stops should allow the anterior portion to
be about 4-5 mm away from maxillary incisors               Possible
Anterior portion should fit comfortably between the lips   incompetent lips
which in place




                                                            Class II Soft Tissue Findings –
       Facebow Expansion
                                                                      Profile View
As the Class II relationship corrects,                     Prognathic maxilla
crossbite will occur if the facebow is not                 Retrognathic
adequately expanded                                        mandible
2 mm expansion is sufficient                               Incompetent lips
Patient will need to squeeze inner bow to                  Strained facial
place it in the tubes                                      musculature




                                                                                                  5
                          Frequent Soft Tissue Findings –
  Dental Findings
                           Frontal View Class III Patient
                          Narrow alar base
                          Deficient zygomatic,
                          paranasal, infraorbital areas
                          Margin of sclera showing
                          below pupils
                          Midface deficiency
                          Thin vermilion border
                          Decreased maxillary incisor
                          exposure at rest
                          Reduced upper lip length




                          Frequent Soft Tissue Findings –
Class II Case - Initial
                                   Profile View
                          Mandibular
                          prognathism
                          Well defined
                          mandibular border
                          Normal neck-chin
                          angle of 120
                          degrees
                          Midface deficiency




                               Frequent Dental/Intraoral
Class II Case - Final
                                      Findings
                          Mesiocclusion of
                          molars and canines
                          Crossbite tendency
                          Buccal crown tipping
                          of maxillary molars




                                                            6
     Frequent Dental/Intraoral
                                     Reverse Pull Headgear
            Findings
Decreased attached gingiva       Forward traction on the
for mandibular anterior          maxilla
dentition
Maxillary retrognathism          Facemask attached to
    Often absent or              banded maxillary
    undersized                   molars by elastics
    maxillarylateral incisors    Side effects include
    Maxillary dental crowding    downward and
    in canine/premolar area      backward rotation of the
Mandibular Prognathism           mandible
    Large tongue with
    crenations, interdental      Lingual tipping of the
    spacing, generalized         mandibular incisors
    open bite




                                      Timing of Any Headgear
   Class III Skeletal Patient
                                            Treatment
                                 Females
                                   8.5-10.5 years old
                                   In general, if menses have occurred,
                                   most of the rapid growth has already
                                   occurred and headgear will not be very
                                   helpful
                                 Males
                                   9.5-11.5 years old




Progress (Between Phase I            More Technical Timing of
      and Phase II)                        Treatment
                                 Hand-Wrist
                                 Radiographs can be
                                 taken with the
                                 cephalometric units in
                                 orthodontic offices
                                 The ossification of
                                 various bones at the
                                 cartilaginous plates can
                                 be compared to an atlas
                                 A more scientific guide
                                 of actual degree of
                                 growth remaining




                                                                            7
   Why Didn’t the Headgear
           Work?




 The Most Important Element



COMPLIANCE!




    Another Possible Factor
•No one can predict how much differential
growth the patient will have during the
treatment time
•Good late growth of the mandible is very
beneficial in the Class II correction with
headgear
•Can be checked by taking serial radiographs
and determining growth of structures during
treatment time




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