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2. INDIAN DENTAL ACADEMY
Leader in continuing dental education
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3. CONTENTS
Mixed dentition treatment approach
1. Habit breaking appliance
2. Myotherapy A. Appliance
B. Exercise
3. Functional appliances
4. Orthodontic appliance
a. High pull HG b. Vertical chin cup
c. Bite block d. Bonded RPE and vertical chin cup
e. Magnetic activator device IV f.. AVC
Permanent dentition treatment approach
Dental open bite – Draw bridge effect (extraction of 1st bicuspid and
retraction of anterior )
Skeletal open bite – A. Questionable growth— MEAW, Bite block,
Skeletal anchorage, Bite block, repelling magnet, spring loaded).
B. Surgical
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4. • Introduction: Vertical malocclusion results from
interplay of many etiological factors during growth
period. These growth factors include growth of
maxilla and mandible, variations in rate of growth in
both the maxillary suture and mandibular condyles
and dentoalveolar development with the eruption of
the teeth. The potential etiological factors other than
unfavorable growth patterns are, digit sucking
habits, lymphatic tissue, tongue and orofacial muscle
activity, heredity, orofacial functional matrices, jaw
posture, head position.
• The correction of vertical dysplasia are more
difficult and more challenging than the correction of
anterior- posterior, transverse malocclusions, hence
the need for proper diagnosis and treatment plan
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5. • Depending on the growth status of an individual
treatment mechanics to be considered.
• Deciduous dentition
• Mixed dentition—Orthopedic
• Orthodontic approach
• Myotherapy
• Habit breaking appliance
• Permanent dentition :
• Dental open bite
• Skeletal open bite
•
A. Questionable growth
•
B. Surgical
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6. • Issacson (1971) and Worms et al believed that
spontaneous correction occurs in upto 80% of
mixed dentition open bite cases and suggested
that interceptive treatment is of little or no value.
Reasoned that Tongue thrust is the main mode of
swallowing upto age of 10 yrs. After that age,
marked decrease in this form of swallowing
account for spontaneous correction.
• Parker &Johnson (1993) believed that
interceptive treatment should be carried out for
the cases that do not self correct.
• INTERCEPTIVE TREATMENT
• 1) Altering mode of breathing.
• 2) Myotherapy.
• 3) Habit breaking appliance
• 4) Functional orthopedic appliance
• 5) Orthodontic appliance.
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7. • ALTERING MODE OF BREATHING
• Altering the mouth open breathing to mouth closed
breathing respond to reduction in lower face height
at an early age.
• According to Linder - Aronson, Adenoidectomy
must be performed at an early age
• (6-8 yrs) to provide a post surgical growth.
• Study by Linder-Aronson and Behltet on postadenoidectomy and post tonsillectomy for 5 yrs
observation period, established hypothesis that
change in mouth open breathing to mouth closed
breathing reverses the symptoms.
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8. • Adenoidectomy
Reduced size of adenoids
Increased nasal flow
Change to nose
breathing
Tongue position and
mandibular position raised
Lips closed
breathing
• Increase width of maxillary arch
• Increase inclination of maxillary and
mandibular incisors.
• Increase in depth of bony nasopharynx
• Decrease lower anterior facial height.
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9. • Contra Indication of Adenoidectomy
• On clinical examination, if palate is
observed to have a bifid uvula/ deep
oropharynx which indicates
palatopharyngeal insufficiency.
Adenoidectomy is contraindicated in such
cases because of the potential for creating
hyper nasality/cleft palate speech.
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10. • Study by WOODSIDE & HENRIKSON LATER,
Confirms this hypothesis and
reasoned that
Change in incisor inclination due to
• (a) Change in tongue and orbicularis oris pressure.
• (b) According to Lowe et al. correlated between
genioglossus muscle and overbite. They
suggested that change in tongue postural activity
exerts definite pressure on incisor tooth.
• Decreased LAFH, due to autorotation and
horizontal mandibular growth.
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11. • MYOTHERAPY
• According to Profitt myofunctional therapy is defined as any
therapeutic approach that involves muscle exercises with
appliance or not. He consider myofunctional therapy as an
adjunct to orthodontic appliance therapy in patient's age 10 or
older i.e. late mixed dentition or early permanent dentition with
a treatment objective to alter resting tongue and lip posture.
This approach takes advantage of function to adapt to form.
Myofunctional therapy is not preventive measure.
• Also A.P.Roger in 1906 suggested that muscle exercise be used
as an adjunct tomechanical correction of malocclusion.
• The principal purpose of myotherapy is creation of normal
orofacial muscular function to aid growth and development of
normal occlusion.
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12. • Exercises
• 1) Ask the patient to hold a piece of paper between the lips.
• 2) Ask the patient to sip water and hold on tongue with the tip
pressed hard against the spot, the patient swallows with biting
teeth firmly together.
• 3) The patient is instructed to practice correct swallowing
pattern by placing the tip of tongue on the palate, close teeth,
close lips and swallow with tongue in that position.
After the new swallowing pattern learned on the conscious level,
it is necessary to reinforce in subconsciously. Flat, sugarless
fruit drops are used to reinforce subconsciously by asking the
patient to hold fruit drops against the palate.
• 4) Place the elastics in tip and dorsum of the tongue and ask the
child to swallow. Child tends to hold the elastics by placing
against palate in proper position.
• 5) Thompson--- Ask the patient to squeeze teeth together as
hard as possible for 15 secs, relax and repeat three times for total
of one minute. This exercise should be done five times a day
(Clenching exercises).
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13. •
•
•
•
•
•
Myoappliance:
1. Lingual pearl
2. Scorpion appliance
3. Blue grass appliance
MYO APLIANCE
1. Lingual Pearl (Jco -98,may) used when tongue is the only
etiology factor responsible for malocclusion. Pearl, elevates the
tongue against the palate. In most cases, the tongue will adapt
to the new position of the dentition. However, to control the
muscular forces of the tongue during space closing or bite
opening, the Lingual Pearl can be attached to a transpalatal bar
or a quad-helix
• A Lingual Pearl can be used in the final phase of treatment of
an open-bite case where vertical elastics were used to close the
bite. Lingual retraining will help prevent reopening of spaces
and subsequent relapse.
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14. • When used during finishing,
the pearl can be bonded to the
palatal sides of the premolars
and remain there until tongue
movement has been
normalized.
• A surgical patient is also a
good candidate for the pearl,
given the abrupt change in
the amount of space available
for the tongue --especially in
an open-bite case.
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15. Scorpion appliance
2. Scorpion appliance Tongue
crib prohibits protrusive tongue
activity during swallowing.
However, the tongue may reach
under the appliance and over the
lower incisors to protrude
anteriorly.
The Scorpion is designed to
provide a prohibitive response to
low anterior tongue posturing
during swallowing.Tongue
movement is controlled in the
vertical plane and is not limited
anteroposteriorly.
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16. • If the tongue ventures between
the appliance and the lower
incisors, the tongue is met by
the spur. The next venture will
then be above the spur and
through the anterior "ring" of
the appliance. The ring directs
the tongue to the normal
dentoalveolar contact.
• This design can also be used on
Hawley retainers during
interceptive or retention
therapy.
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18. • 1. Tongue crib appliance
• Act as inhibitory appliance, inhibits the thumb
sucking habit and tongue thrusting habit. The
appliance for the anterior open bite patients consists
of a palatal acrylic plate with horse shoe-shaped
wire crib and labial bow. The length of the crib is
usually 6-12 mm and placed 3 to 4mm lingual to
the upper incisors. If the crib is placed at the
gingival third, a proper adjustment can stimulate
the eruption of the anterior teeth, thereby useful in
the correction of the open bite. The acrylic can also
be interposed between the teeth, covering the
occlusal surfaces of the upper molars, in order to
prevent the eruption of the posterior teeth.
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19. • Posterior tongue crib appliances are used to correct the
unilateral (or) bilateral open bite, by preventing the lateral
thrust of the tongue.
• Fixed tongue crib is also used for the correction of open
bite by banding to the abutment teeth [molars].
• Haryett reported that cribs were very effective in stopping
the habit when they were worn for 10 months.
• Cooper & Skewida reported that tongue crib appliance
alone is not effective in closure of open bite.
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20. • Vestibular screening appliance
• This appliance extends into the vestibular sulci and
eliminates pressure without creating tension in
periosteum, to enhance bone in periosteum. This
shield interrupts the contact between tip of tongue
and lower lip, which leads to maturational
deglutitionand indirectly influence tongue position.
These appliances removes abnormal sucking
habits, lipdysfunction and establishes proper oral
seal.
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21. • It is a screening appliance
used to correct the mouth
breathing habit.
Construction: edge-toedge bite is taken without
the consideration of the
facial pattern. This bite
does not predetermine a
precise mandibular
forward posturing but
requires only that the
mandible be moved
forward to edge to edge
relationship.
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22. • The acrylic shield should extend vertically from the
upper labial fold to the lower labial fold and extends to
the distal margin of the last erupted molar. It should be
in contact only with the upper and lower labial fold
during the anterior positioning of the mandible.
• If the crib is placed at the gingival third, a proper
adjustment can stimulate the eruption of the anterior
teeth, thereby useful in the correction of the open bite.
The acrylic can also be interposed between the teeth,
covering the occlusal surfaces of the upper molars, in
order to prevent the eruption of the posterior teeth. Lip
exercises should be advocated along with it. Lip
exercises such as holding a piece of paper between the
lips while wearing the vestibular shield is advocated
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23. • It is effective in eliminating the mouth breathing
habit, abnormal sucking habits and lip dysfunction
in order, to achieve a proper lip seal, which is of
prime importance. This lip seal will indirectly
influences the posture of the tongue, and thereby
leading to maturation of the deglutition cycle and
creates a somatic swallowing pattern.
• The appliance is usually worn at night and 2 to 3
hours per day when the child is not in school.
• This appliance only eliminates the pressure. It
cannot create a tension effect on the vestibular
periosteum to enhance the bone formation in this
region. The most important factor in treatment is to
have a soft tissue seal of the screen with no strain in
the peripheral portions.
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24. • Modification of the
vestibular screen are,
vestibular screen with
holes at the inter-incisor
area for certain patients,
who find difficult in the
breathing, vestibular
screen with the tongue
crib, and vestibular
screen with the acrylic
tongue crib.
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25. •BLUE GRASS APPLIANCE (Habit breaking and Tongue
Retainer)
• Haskell & Mink (in 1991)
introduced easy to wear appliance
called Bluegrass appliance. He
used a hexagonal Teflon roller on
a cross palatal wire. He claimed
that appliance almost always ends
a sucking habit within several
days, if not immediately and
begins training the tongue
towards a normal posture.
Normalizing facial growth and
allowing proper speech. They did
not recommend this appliance for
pre-school age children.
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26. • Chris baker (2000) modifiedthe Bluegrass appliance design to
utilize4mm acrylic beads on the cross palatalwire. Advantage of
modification
• It encourages the maximum neuromuscular stimulation by using
two or more beads
• It reduced bulkiness of appliance, which results in less
obstruction and more stimulation of tongue function.
• Wire and beads cemented to second a deciduous molar that is
not seen from outside mouth. A child quickly becomes
comfortable with the Bluegrass and enjoys the sensation of the
tongue playing with the beads.
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27. • Chris baker claimed that there is a direct
relationship between the age of child at the time of
appliance placement and speed of correction.
• Younger children show cessation of habit in first
few days and quickly and completely tongue
position becomes normalized.
• Older children --- take few weeks.
• Retention :
• Appliance left in the mouth for six months after the
habits has stopped. If the low tongue position
persists after six months, leave the appliance in
place to continue retraining.
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28. Nanda found that the vertical
pattern of development was
established before the eruption
of the permanent first molar and
long before the adolescent
growth spurt. Anterior vertical
dimension is a key feature
that is related to existing vertical
growth patterns.
VHA, is essentially a
transpalatal arch with an acrylic
pad. The VHA uses tongue
pressure to reduce the vertical
dentoalveolar development of
maxillary permanent first molars
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Vertical holding
appliance
29. ORTHOPEDIC APPROACH
Functional appliance in growing patient
Activator
Principle
Woodside viscoelastic properties of muscle
contraction induces skeletal adaptation.
Activator can be used for vertical malocclusion
especially in open bite cases to eliminate tongue
thrusting, finger sucking and facilitates eruption of
anterior teeth, prevents eruption of posterior teeth
and facilitates mandibular growth.
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30. • Eschler (1952) says that if the bite opening with
activator increases 4 mm beyond postural position,
it will act as a muscle stretching method, works
alternatively with isotonic and isometric muscle
contractions. He describes the cycle as at the
insertion of the appliance the mandible is elevated
by isotonic muscle contractions and when the
mandible assumes a static position with the
appliance, isometric contract arise. Because the
mandible cannot reach the postural rest position,
the elevators remain stretched. When the fatigue
occurs, the contracting muscle relaxes and the
mandible drops. As soon as the muscle has
recovered, the cycle begins again
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31. • Bite registration :
• The forward positioning of the mandible is not
necessary, when this appliance is primarily used
for the vertical problems.
• Hence, the bite is opened 4 to 5 mm beyond
postural rest position to develop sufficient elastic
depressing force and load the molars that are in
premature contacts. This appliance is used to
achieve retroclination of the maxillary base with
the restriction of the patient's vertical growth
pattern. This will "close the V" between the upper
and lower maxillary bases, depressing the posterior
maxillary segment. If the divergent rotations of
the jaw bases are present, the correction of open
bite with activator is not possible.
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32. • Weinback & Smith (AJO 1992) evaluated the
effectiveness of appliance;
found that there is decrease of
1.3mm in open bite and has
less effect on lower molars .
• Limitation- When divergent
rotation of base is apparent,
activator is not the choice of
treatment.
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33. • Intrusion of molars is performed
by loading only the cusps of these
teeth. The acrylic detail is ground
away from the fossae and the
fissures to eliminate any possible
inclined plane stimulus to molar
movement to achieve vertical
depressing action. This will allow
the activator to deliver greater
amount of force.
• Extrusion of the incisors requires
loading their lingual surfaces
above the area of greatest
concavity in maxilla and below
this area in the mandible. And the
extrusion can be enhanced by
placing the active labial bow
above the area of greatest
convexity (gingival third).
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34. Vertical Control with a
Headgear-Activator Combination
• The rigid acrylic activator
consists of two parts: an
upper “ horseshoe” splint
covering all the teeth up to
the gingiva, and a lower
portion adapted lingually to
the mandibular arch and
alveolar process, with lower
wings as long as possible.
Labial coverage of the incisal
edges can be added to
prevent proclination of the
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incisors.
35. High angle cases are particular domain of this
combination since, unlike the use of activator only
treatment, vertical control is optimal.
• In vertically critical cases the force vector of the
headgear is adjusted so that even pressure is
distributed between the incisal and molar regions, i.e.
through the centre of resistance of upper dentition. No
acrylic is removed in the lower molar region. The
amount of force should not be less than 400 gm.
• By changing the direction of the outer facebow, it is
possible to achieve different biomechanical effects on
both the alveolar and skeletal units. Moments can be
positive, negative, or nonexistent, resulting in
clockwise rotation, counterclockwise rotation, or pure
translation, according to treatment objectives.
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36. • Lowering the outer facebow
enhances the tipping effect
of the activator, thus
increasing anterior overbite
and reducing posterior facial
height. This effect should be
avoided in brachyfacial
cases, but can be used to
advantage in mesofacial or
dolichofacial types with
tendencies to anterior open
bite .
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37. Since the outer facebow was bent downward so the direction of
force passed behind both the alveolar and skeletal centers of
resistance. Thus, positive moments and clockwise rotation
were generated
• Clockwise rotation of the palatal plane,
• Downward tipping of the occlusal plane without eruption of
the upper molars.
• Eruption and retroclination of the upper incisors, resulting in
correction of the overjet and anterior open bite.
• Closing of the facial axis and anterior mandibular rotation,
with forward displacement of pogonion.
• Inhibition of forward maxillary growth, combined with
forward mandibular growth, resulting in correction of the
Class II skeletal relationship.(disadvantage in class 3 cases )
• Backward displacement of the upper dentition and forward
displacement of the lower, without tilting of the incisors,
resulting in correction of the Class II malocclusion.
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38. • Bionator
• Bionator mainly used to correct abnormal posture and
function of tongue.
• Principle
• 1) According to Balter, equilibrium between tongue and
circumoral muscles is responsible for shape of dental arches
and intercuspation. The functional space or the tongue is
essential to the normal development of the orofacial system.
• 2)Not to activate muscles but to modulate muscle activity,
thereby enhancing normal development of inherent growth
pattern and elimination abnormal and potentially deforming
environmental factor.
• 3) Construction bite is as low as possible with slight opening
for posterior bite block to prevent extrusion of posterior
teeth.
• 4. To inhibit tongue movement, the acrylic portion of lower
lingual part extends into upper incisor region as a lingual
shield closing the anterior space without touching upper
teeth.
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39. • The palatal bar is used to
position the tongue more
posterior (or) into caudal
position.
• The labial bow should run
between the incisal edges of the
upper and lower incisors. The
labial part of the labial bow is
placed at the height of the
correct 'lip closure, thereby
stimulating the lip to achieve a
competent lip seal and
relationship. The vertical strain
on the lip tends to encourage the
extrusive movement of the
incisors, after eliminating the
adverse tongue pressures
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40. Weinback et al (AJO-92) concluded that openbite bionator is
not useful in severe open bite cases and useful in mild case
were posterior eruption would be undesirable due todivergent
skeletal pattern.
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41. Frankel FR- IV
• Out-to be matrix'-Allows muscle
to exercise to adapt. The working
principle of R, establishes the
mandible forward rotation with
posterior edges of buccal shields
as rotational centers. Anteriorly
the force of anterior vertical
muscle chain being strengthened
by lip seal exercise raises the
mandible.
• Appliance effectively changes
dentoalveolar structures without
producing skeletal changes.
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42. OWEN s modification of a function
regulator differs from other Frankel
appliances in the addition of posterior
acrylic bite blocks to arrest molar
eruption through the function of the
elevator muscles.
The vertical dimension or anterior
facial height (ANS-Me) decreased
through the holding or intrusion of the
upper molars.
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43. It also has headgear tubes that accept a facebow for an
occipital pull headgear, which provides the appliance
with positive control of the posterior maxilla
The construction bite was taken 3-4mm protrusive, with
3-4mm posterior (molar) clearance to allow for the bite
blocks and headgear tubes
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45. • Study by Erbay et al (AJO-95) showed that this
appliance produce favorable mandible rotation
with extrusion of upper and lower incisors thereby
correcting malocclusion. As a result of treatment
with the FR-4 appliance and lip seal training, the
growth and development pattern of the mandible
was altered. The spontaneous downward and
backward growth direction of the mandible which
was observed in the control group was changed to
an upward and forward direction by FR-4 therapy,
allowing the skeletal anterior open bite to be
successfully corrected through upward and
forward mandibular rotation.
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46. • Reduction in total anterior facial height growth was due to
successful inhibition of lower anterior facial growth by the
FR-4 appliance. It appears most likely that this reduction in
mandibular plane angles was the result of differential
increase between total posterior and anterior facial height
(4.5 and 3.9 mm, respectively). Greater posterior vertical
growth would result in a lowering of the gonial region and
subsequent upward and forward mandibular rotation.
Theoretically, Fränkel and Fränkel explained this rotation
mechanism with the possible effect of the function
regulator's buccal shields and lip seal exercises. They
hypothesized that the posterior edges of the buccal shields
are deeply positioned in the vestibular sulcus and provoke
pressure sensation in this area. This could cause the inferior
translation of the posterior part of the mandible with a
compensatory translative growth at the condyles, leading to
an increase in ramus length. They suggested that,
concomitant with the lowering of the posterior part of the
mandible, its anterior part could be raised with the posterior
edges of the FR as www.indiandentalacademy.com
a rotational center.
47. • They concluded that such a forward rotation of the
mandible was brought about by the force of the
vertical muscle chain being strengthened by lip
seal exercises. This hypothesis is supported by the
findings of Ingervall . They found considerable
anterior mandibular rotation in children with longface structure during muscle training with chewing
gum. However, Ingervall suggested the anterior
mandibular rotation could be explained by reduced
midfacial vertical growth due to increased
masticatory muscle strength, instead of increased
mandibular condylar growth.
• The occlusal rests of the FR-4 appliance on the
upper first molars appear to restrict the rate of
growth in upper posterior dentoalveolar structures.
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48. • Twin blocks
• Twin blocks with modification can be used to achieve
vertical control and includes posterior & also erupts
anterior, which aid in correction of excess vertical height
malocclusion especially in mixed dentition. The principle
of this appliance is to correct the malocclusion by
correcting the unfavorable cuspal contacts and maximize
the growth potential of the jaws. Rapid correction of the
malocclusion is achieved by transmitting favorable
occlusal forces to the occlusal inclined planes covering
the posterior teeth. In treating the patients with vertical
growth pattern associated with increased lower facial
height, the contact between the occlusal bite blocks and
the posterior teeth should be maintained to prevent the
eruption of the posterior teeth.
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49. • Modifications :
• 1.A palatal spinner comprising of a bead which rotates on a
transpalatal wire ositioned in the palate which encourages the
tongue to curl upward and backward instead of thrusting between
teeth.
• 2. Twin block with headgear to upper 1st molar
• (Intrude and corrects VME)
• Headgear tubes can be attached to the upper molar and high pull
extra-oral traction can be applied to a modified face bow worn at
night to intrude the upper molars.
• 3. Concord face bow is a unique way to deliver an intrusive
force to upper molar and protrusive force to the lower molar.
• In the Concorde face bow, the outer bow should be slightly above
than the inner bow, producing an upper component of force, to
stabilize the upper appliance. This upward force is balanced by
the horizontal elastic attached to the recurved labial hook and the
vertical component of orthopedic force is applied to the upper
molars by cervical headcap (or) headgear.
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51. • 4. Vertical elastics used to twin blocks to upper and
lower posterior premolar regions which helps in
intruding posterior teeth thereby altering vertical
dimension.
They intrude the posterior teeth especiaIIy the upper
molars, by encouraging the patient to bite into the
appliance consistently and producing more
amounts of intrusive forces on the opposing molars.
This effect is useful to the patients with vertical
growth pattern and weak musculature and so they
do not close consistently on the appliance.
• 5. Use of repelling rare earth magnets in the
occlusal bite blocks to reduce the vertical
dimension.
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52. • JASPER JUMPER
• This appliance produces both sagittal and intrusive forces like
Herbst bite jumping mechanism, but affords the patients much
more freedom of mandibular movement.
• The Jasper Jumper is relatively new auxiliary capable of
producing rapid change in occlusal relationships. It is flexible
fixed appliance that delivers light continuous force. It can be
used to move single teeth, most of teeth or an entire arch. It
can deliver functional bite jumping forces, or a combination of
these.
• Its modular system can be attached to most commonly use
fixed appliances.
• This system is composed of two parts, the force module and the
anchor units.
• ROBERT G.CASH57, 1991 had described the non-extraction
treatment for on adult patient with a bilateral Class II
malocclusion and an open bite, using a Jasper Jumper
appliance to distalize and to intrude the maxillary molars.
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53. • ORTHODONTIC APPROACH to limit
vertical dimension, in growing patient are:
• High pull headgear with/without splint
• Extraction therapy
• Bite blocks (passive/active)
• Vertical pun chin cup
• Combination of these.
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54. • High pull headgear
• Used to treat hyperdivergent open bite, by
effectively holding maxillary sutural rowth and
vertical dentoalveolar development (Armstrong,
Woodside and Baumrind).
• Study by Creekmore and Pearson, showed that
high pull headgear alone modifies maxillary
growth but compensatory eruption of mandibular
molars prevents autorotation of mandible and
control of anterior facial height.
• Study by Melsen and Caldwell, showed that high
pull headgear attached to a splint more effectively
modifies maxillary growth to a more
posterosuperior direction and this is an effective
approach for vertical maxillary excess
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55. Maxillary traction splint:
• Caldwell (AJO-84) used acrylic
splint With headgear (high pull)
showed that, this approach
produce a superior and distal
displacement of maxilla, reduction
in SNA angle, clockwise rotation
of palatal plane and relative
intrusion of upper molar with
increased lower molar eruption,
decreased mandibular growth and
increased SNB angle.
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56. 1. High pull HG short and high outer
bow: Line of HG force is mesial to
Centre of resistance.
• Moment tends to flatten the OP.
• Distal and intrusive force component.
2. HG force passing through center of
resistance.
Intrusive and distal component of
force. No moment.
3.High pull with long outer bow:
•
•
•
Moment at center of resistance tends
the steepen the OP.
Force with distal and intrusive
component.
Indication : Class II open bite patients.
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57. Vertical chin cup
• Pearson used vertical chin up in mixed and
permanent dentition to reduce the Mpa and limit
in increase in anterior facial height.
• Haas used vertical chin cup with Kloehn cervical
headgear, and showed that appliance inhibit
upper molar eruption and descent of maxilla,
while mandibular growth was redirected toward a
more horizontal direction.
• Cups have ben used during active RPE therapy to
minimize the vertical displacement of the maxilla
and control the opening of MPA.
• Eren studied the effect of vertical chin cup alone
and found a decrease in Mpa, posterior rotation of
maxilla, increase in upper facial height, a decrease
in total anterior and lower anterior facial height,
an increase in lower post dentoalveolar height and
an increase in overbite.
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58. • Study by Iscan (AJO-2002) effect of vertical chin cup on
mandibular morphology in treating Skeletal open bite.
Concluded that Mpa decreased significantly. Gonial angle
closed, ramal inclination angle decreased, corpus inclination
increased all indicating anterior rotation of mandible.
Anterior rotation of mandible occurred as a result of
inhibiting vertical growth in mandibular post dentoalveolar
region. Eruption of mandibular incisors played an important
role in correcting open bites in vertical chin cap therapy.
• Study by Pearson, showed that mandibular plane angle
decreased to 3.9°, with all 4 extractions and a vertical pull
chin cup for 9 months of treatment.
• Study by Nanda, showed that high pull chin cup prevents
increase in anterior facial height and mandibular plane angle
in hyperdivergent individual during maxillary expansion.
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59. Passive posterior bite block
Do not contain any active elements like springs/magnet.
According to Kuster et al bite blocks are like functional appliances,
with interocciusal space of 3-4 m beyond rest position, which
inhibit extrusion of buccal segments effectively.
This is most effective prior to growth completion of jaws.
Modification of bite blocks
1.Removable spring loaded - Kuster & IngeNal (AJO-90) It shows
greater reduction in ANB angle and molar intrusion than passive
bite block.
2. Repelling magnet - Iscan et al (AJO-97)
3. Active vertical corrector (AVC) - Dellinger(AJO-86)
-Tooth borne appliance
-Fixed/ Removable type
Advantage
Rate of tooth movement is greater than conventional appliance such
as high pull headgear, bionator, activator (or) conventional bite
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block therapy. Correction of LAFH range from 0.9 - 2.4 mm
60. • BITE BLOCK
• DELLINGER (1986) proposed the use of occlusal bite
blocks containing repelling magnets, the effect of the
force of the magnets was reported to cause intrusion of
the posterior teeth, allowing the mandible to rotate
upward and forward.
• Michael G. Woods and Ram S. Nanda (1988) in their
experiment in growing baboons found magnetic bite
blocks are effective in intrusion of posterior teeth.
There was significant eruption of anterior teeth. This
dentoalveolar compensation was greater in animals
wearing magnetic appliances than bite blocks without
magnets. Bone remodeling changes at the gonial angle
wear also marked with magnetic appliances.
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61. • Study by Thilander & Dellinger, showed that a
bite block is effective in controlling anterior
facial height.
• Study by McNamara and Dellinger, showed
that magnetic bite blocks produce significant
treatment effect with the disadvantage
• a) Creating asymmetric mandibular posture and
subsequent unilateral cross bites due to
shearing forces created by repelling magnets.
• b) Increased root resorption due to excessive
intrusive force for extended periods.
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62. • Kalra and Nanda (AJO 1989 )
• A fixed magnetic appliance was
designed that hinged the mandible
open and exerted an intrusive force
on the teeth. Treatment with this
appliance resulted in:
• An increase in length of the
mandible ( age group 8 – 10 yrs )
• Intrusion of teeth
• Upward and forward autorotation
of the mandible
• Reduction of A-B to occlusal plane
• Improvement in the angle of facial
convexity
• Creation of temporary buccal
crossbite caused by the shearing
force of repelling magnets
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63. • The MAD IV Appliance
• M. ALI DARENDELILER (JCO)
• The Magnetic Activator Device IV (MAD IV) uses
anterior attracting magnets as well as posterior
repelling magnets. The anterior magnets guide the
mandible into a centered-midline position, add an
anterior closing effect, and enhance the anterior
rotation of the mandible.
• The MAD IV consists of removable upper and lower
plates, each of which contains three cylindrical
neodymium (Nd2Fe17B) magnets coated with
stainless steel. The four posterior magnets,
embedded in a repelling configuration, generate an
intrusive force of 300g each, with a bite opening of
5.5-6mm at the first molars. The two midline
magnets apply an attracting force of 300g.
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64. • 1. The MAD IV-a is used
in cases where the anterior
segment of the maxilla is
vertically correct or
overdeveloped (gummy
smile). Because posterior
intrusion and mandibular
autorotation are needed,
the posterior and anterior
magnets are placed in full
contact
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65. • 2. MAD IV-b is used when
an additional extrusive effect
is needed in the maxillary
anterior region. The anterior
magnets are positioned with
a vertical opening of 2-3mm,
while the posterior magnets
are placed in full contact.
These selective anterior and
posterior effects can be
accentuated by dividing the
upper plate in two and
joining the two sections with
a hinge.
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66. • . The MAD IV-c is used
when only anterior
extrusion is needed. The
posterior magnets are
omitted, and the anterior
magnets are placed with
an opening of 1-2mm,
depending on the
severity of the anterior
open bite.
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67. • THE ACTIVE VERTICAL CORRECTOR
(AVC )
• Active Vertical Corrector (AVC) is a
simple removable or fixed orthodontic
appliance that intrudes the posterior teeth
in both the maxilla and mandible by
reciprocal forces. AVC is a tooth borne
appliance.
• By the use of effective posterior intrusion
of teeth, the mandible is allowed to rotate
in upward and forward directions. The
uniqueness of this appliance is that it
allows the clinician to correct anterior open
bite problems by actually reducing anterior
facial height.
• It is an adaptation of present-day bite
block therapy .
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68. • The AVC works as an energized
bite block. The energy system is
obtained by the repelling force
of samarium cobalt magnets.
Because samarium cobalt is a
highly reactive, rare earth
material and therefore best kept
isolated from the oral
environment, these magnets are
hermetically sealed in a stainless
steel capsule. Stainless steel was
selected over epoxy as the
material for encasing the
magnets because epoxy tends to
crack and abrade from occlusal
contact.
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69. • The method of action is
reciprocal intrusion of the
maxillary and mandibular
teeth This movement results in
autorotation of the mandible
and open bite correction. The
force system presently used in
this appliance generates 700 g
of force per magnetic unit. The
magnets are placed
immediately over the teeth to
be intruded. The placement is
viewed as a pure vector
problem and varies from case
to case. One or two magnets
per distal quadrant are used,
depending on the force
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required.
70. • Method of action
• The AVC force system generated by repelling
magnets is considered superior to a static bite
block appliance energized only by the intermittent
force from the muscles of mastication. The
constant force system of the AVC results in
greater rapidity of tooth movement. It has been
shown that increased cellular activity occurs when
tissues are subjected to an intermittent
electromagnetic field. Saliva is an electrolyte and
the magnets are at times in motion. The possibility
of microcurrent flow in the periodontium should
be considered a positive tissue stimulator.
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71. • The rate of tooth movement is considerably greater than
conventional approaches such as high-pull headgear,
Bionators, activators, or conventional bite block therapy.
• The impressions for constructing the dental casts are critical
because the taking of the working bite demands a precise
clinical technique and is an absolutely essential element in the
correct functioning of the AVC. Another extremely important
factor is the placement of the magnets because the appliance
is a direct reciprocal vector appliance between the maxilla and
mandible. A specially designed headcap and chin strap is
worn during sleep and at all other times deemed socially
fitting by the patient.
• The appliance has been successfully used in both adults and
children, growing children experience more rapid correction
than the skeletally mature adult.
• Study by Ingervall showed that AVC produce quicker
response in dental and skeletal vertical relationship in
growing individuals. i.e. an average of 3mm of anterior open
bite closure over a 8 months treatment period.
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72. OPEN BITE CORRECTION IN INDIVIDUALS
WITH NO POETENTIAL FOR GROWTH
MODIFICATION
• Dental open bite
• Wiseman (AJO-95), provides a guideline to treat dental open
bite.
• 1) Prociined maxillary/mandibular incisors,
• 2) Normal craniofacial pattern
• 3) Little/no gingival smile
• 4) 2-3 mm of incisor exposure at rest.
• His approach is extraction and retraction of incisor, commonly
involved teeth for extraction is 1st premolar . Mechanics of
treatment aimed at changing angulations and extrusion of
anterior teeth (Draw bridge effect). The limiting factor in this
type of treatment is relationship of upper incisor to upper lip.
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73. • YOUNG H.KIM 1987 has described the multi loop edgewise
Archwire
• (MEAW) technique in the treatment of the Anterior openbite. The MEAW technique
• 16x22 SS archwire + heavy anterior elastics - to achieve
molar intrusion and simultaneous incisor extrusion.
• 1. ELIMINATE all rotations, spaces and crowding before
treatment.
• 2. Double edgewise brackets with .018 slots, preferably
auxilIary vertical slot are used.
• 3. Two types of loop components, vertical and horizontal.
Vertical loop provides’ horizontal control and horizontal loop
provides vertical control.
• 4. Individual loops are in the form L shape.'• 5. Using 2 1/2 times (30 cm) more than the normal span of
wire, it provides ten-fold reduction in the load/deflection rate
over a typical ideal archwire.
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74. • 6. Requires 5 loops on each side.
• 7 Vertical loops centered at the interproximal areas horizontal
loops should be directed mesially.
• 8. Typical tip back bends 3° to 5° should be incorporated.
• 9. Upper MEA W has deep curve of spee and lower reverse
curve; this will apply intrusive forces on incisors further
worsening the open-bite. So this force is counteracted by
anterior vertical elastic force. The elastics must be in a place for
full-time.
• He concluded that the MEAW technique is very effective in the
treatment of the open-bite. In addition he says that the
extraction 2nd or 3 rd molar in open-bite cases offers feasible
diagnostic and therapeutic situation and while treating the open
bite, individual occlusal plane should be corrected, teeth must
be uprighted to occlusal plane for stability and function.
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75. •
•
•
•
•
•
•
•
Effect
Increase upper anterior alveolar height
No effect on upper posterior alveolar height.
Reduction in lower posterior dentoalveolar height
Distal movement of entire dentition.
Increase in inter incisal angle.
Alters the occlusal plane by preventing upper
molar extrusion and intrudes lower molar.
MEAW influence dentoalveolar changes with
minimal effect on skeletal pattern.
Limitation - Patients with gingival show.
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76. Implants
• As Stationary Anchorage
• Prosterman et al (AJO-95) used Osseo integrated implants
to intrude/at least prevent extrusion of posterior segment in
correction of vertical facial height and anterior open bite.
• Umemori at al (AJO-98) used titanium miniplates in
buccal cortical bone in apical region of 1st & 2ndmolars
and produce 3-5 mm of intrusion and counter clockwise
rotation of occlusal plane without unfavorable side effect.
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77. Leibinger miniplates, screws,
and screwdriver.
The plate should be positioned
so that only the last loop on
the vertical (most occlusal)
leg of the plate projects
through the mucosal incision
into the oral cavity. This loop
should be several millimeters
apical to the brackets on the
molars and adjacent to the
teeth requiring the greatest
amount of intrusion. Two
self-tapping screws are
placed to secure the plate to
the bone.
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78. • Since the intrusive force is buccal
to centre of resistance , molar
buccal flaring can occur. Lingual
crown torque was applied to the
lower molars with Burstone’s
precision lingual arch to avoid
buccal flaring during intrusion . In
the upper arch TPA can be used.
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79. SURGICAL TREATMENT
When the severity of vertical deformity is so great that reasonable
correction cannot be obtained by growth modification/camouflage,
a combination of orthodontics and orthognathic surgery is the
viable treatment option.
Ways to counteract this malocclusion:
1) Superior repositioning of the maxilla (or) at least posterior part of
the maxilla by total/segmental maxiiiary osteotomy. This indirectly
repositions the mandibie in an upward and forward direction. Care
taken not to elevate anterior maxilla and may be indicated to rotate
downward so that an esthetic smile arc is maintained.
2). Mandibuiar surgery to bring lower jaw forward and upward, in a
open bite cases, by fitting he body of mandibie up after a ramus
osteotomy (this approach indicated when problem is largely in
mandible and no alteration in maxilla is required).
3).Superior repositioning of chin by mandibular lower-border
osteotomy. This procedure is useful adjunct to above approaches,
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but it is not adequate to solve severe discrepancy.
80. 4).Double jaw procedure - Maxillary surgery is the primary
procedure. After maxilla repositioned vertically, mandibular ramus
osteotomy is recommended only as a secondary procedure.
5) Glossectomy
In cases where abnormal large tongue is the causative factor in
excess vertical facial height, partial glossectomy procedure is
recommended. And also where tongue is large to small mandible,
either functional orthopedic appliance/jaw advancement surgery is
indicated (Bite jumping).
Primary focuses on maxilla, for two reasons
• Usually the maxilla has excessive vertical development with
influence on mandible rotation down and backward.
• Stability - moving maxilla up produces stable surgical correction,
whereas mandibular ramus osteotomy in a counter clockwise
rotation stretches soft tissue posteriorly resulting unstable.
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81. • INDICATIONS
• 1. Cases where normal mandibular length, rotated to
Class II pattern, superior repositioning of maxilla
alone will bring mandible to Class I.
• 2. Cases where small mandible and rotated backward,
superior repositioning of maxilla and mandibular
ramus osteotomy indicated(For advancement of
mandible).
• 3. Cases where large mandible and rotated backward,
i.e. (ClassIII to Class I), superior repositioning of
maxilla and mandibular ramus osteotomy indicated (to
shorten mandible
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82. • Presurgical Consideration
• 1) Lefort-1 osteotomy has tendency of gingival stripping during
healing process, scar contractions pulls gingival attachment
gingivally. When gingival attachment is questionable. gingival
attachment should be augmented by placing gingival grafts in
doubtful areas atleast 2-3 months before surgery (esthetic
problem).
• 2) In anterior open bite planned for segmental maxillary
osteotomy with anterior and posterior dentoalveolar segments, it
is important not to level upper arch during presurgical
orthodontics.If upper arch is leveled presurgicalty,in severe open
bite cases. produce a relapse tendency, i.e. primarily leveling
occurs by elongating upper incisor. When appliance removed
post surgically the incisors tend to relapse apically to some
extent and would lead to opening of bite anteriorty.
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83. • 3) Transverse, If arch requires expansion orthodontically, do at
the very beginning of presurgical orthodontic procedure and
maintain as long as possible before the expansion appliance is
removed. If arch expansion planned at surgery, orthodontic
expansion should not be carried out in presurgical procedure.
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84. • ANTERIOR MAXll,LARY AND MANDIBUULAR SUB
APICAL OSTEOTOMY
• This surgery is mainly executed for the extrusion of the anterior
segment of maxilla (or) mandible (or) both to close the anterior
open bite.
• Indication for anterior maxillary sub-apical osteotomy:
• 1..A small open bite associated with the minimal tooth exposure
(or) none,lip competence, a good naso labial angle, and adequate
lower anterior facial height
• 2.The relationship between the upper lip and concealed maxillary
incisors of rest,speech and smiling produces an unaesthetic
edentulous appearance.
• Indication for anterior mandibular sub-apical osteotomy: If the
open bitemanifests in the anterior portion of the mandible as a
reverse curve in the mandibular archwith transverse maxillomandibular harmony and good esthetic balance between upperlip
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and maxillary anterior teeth. Relapse potential is very minimal.
85. KOLE MODIFICATION OF MADIBULAR SUB-APICAL
OSTEOTOMY
Indications :
Mandibular prognathism associated with anterior open bite, severe
reverse curve, and excessive chin height along with the patient should
have a functional posterior occlusion, no transverse deficiency
problem in maxilla and a satisfactory lip to tooth
relationship in maxilla.
.
The main objective of this surgery is the close the open-bite by elevating
the lower anterior segment and reducing the chin height it includes
horizontal sub-apical bone incision and vertical ostectomies in the
premolar (or) molar extraction sites.
The choice of extraction site depends on the magnitude of the anterior
open bite and location of the reverse curve in the mandibular occlusal
plane.
.The principle disadvantage of the surgery relates to unpredictable soft
tissue profile and chin height changes. So that a well placed pressure
dressing for 7 days minimizes the soft tissue changes.
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86. • LEFORT I MAXILLARY OSTEOTOMY FOR
THE CORRECTION OF THE VME
• This surgical procedure is indicated in cases with high and
constricted palatal vault, excessive curvature of the
maxillary occlusal plane, lip incompetence high mandibular
plane angle and a long distance between the palatal roof
apices and the nasal floor.
•
This down fracture Le fort I osteotomy is more useful
when interdental osteotomies are indicated to level the
maxillary occlusal plane, widening the maxillary arch, less
problematic, more versatile and easier to execute than
anterior (or) posterior maxillary osteotomies.
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87. • Post-surgical orthodontics
• The most difficult part in post-surgical
orthodontic in long face is maintaining
transverse maxillary expansion, particularly
surgical expansion. To stabilize transverse
expansion, Heavy labial auxiliary wire in
headgear tube along with light working
archwire.
• Transpalatal lingual arch.
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88. Surgical management of the growing patient
• Surgical management of the growing patient remains controversial.
Growing patients can present to the clinician with maxillary
dentofacial deformities that require combined surgical and
orthodontic correction.
• Around 12 years of age, most transverse maxillary growth is
complete.Anteroposterior (AP) growth of the maxilla is basically
complete by about the age of 14 years. Normal vertical maxillary
growth, however, continues into adulthood.
•
Early surgical correction may be beneficial in some patients for
functional, esthetic, and psychosocial reasons.If surgery is
performed during growth, the patient and parents must be informed
that future surgery will probably be necessary. Surgery is often
undertaken with the expectation that additional treatment,
including more surgery, may be required after the completion of
growth.
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89. • Le Fort I maxillary osteotomy.
The Le Fort I osteotomy , when
performed during growth, effectively
inhibits further anterior growth of the
maxilla. Vertical maxillary growth,
however, can be expected to continue
postoperatively at the same rate as
before surgery.
• In patients with normal mandibular
growth, the occlusion should remain
stable.
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90. • Horseshoe maxillary osteotomy
(dentoalveolar osteotomy).
• With the horseshoe maxillary
osteotomy procedure the nasal septum
remains attached to the stable palate, and
only the dentoalveolar structures are
mobilized. Thus, some AP maxillary
growth may be expected to occur
postoperatively. The overall growth rate,
however, will remain deficient.
• Vertical maxillary growth remains
unaffected and continues at the same rate
as before surgery
• Tunnel procedure -- risky
• Flap-- Raised labialy and buccaly
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91. • The most predictable results will be obtained if surgery is
performed after age 14 in girls and age 16 in boys. If done at
an earlier age (12 years in girls and 14 years in boys), there
is a possibility of the excessive vertical maxillary growth
rate recreating a vertical maxillary excess after surgery,
although to a lesser extent than would occur if surgery was
not performed. The occlusion will usually remain stable
• Either procedure can be performed before the patient reaches
age 10, provided sufficient space exists above the apices of
the developing permanent teeth to place the osteotomies and
apply fixation. Damage to developing tooth roots may result
in dento-osseous ankylosis, and localized dentoalveolar
growth impairment.
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92. • Orthognathic surgery for the correction of
vertical maxillary hyperplasia can be
performed with corrective mandibular
surgery for retrognathia or prognathism, if
the preoperative rate of mandibular growth
is normal, and the TMJs are healthy. The Le
Fort I osteotomy will inhibit further AP
maxillary growth while allowing vertical
maxillary growth to continue.
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93. • Sagittal split ramus osteotomy.
•
The sagittal split ramus Osteotomy is
more difficult to perform on younger
patients because of greater bony
elasticity, the thinness of the cortical
bone, the presence of unerupted molar
teeth, and the relatively shorter
posterior vertical mandibular body
height, as compared with adults. It does
have the advantages of easy application
of rigid fixation as well as better
positional control of the proximal
segment. SSRO is best reserved for
patients over the age of 12 years—that
is, after the eruption of the permanent
second molars, so that damage to these
teeth during surgery can be avoided.
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94. • Vertical ramus osteotomy.
•
The vertical ramus osteotomy (VRO)
can be used to advance the mandible
and vertically lengthen the ramus with
appropriate bone or synthetic bone
grafting as indicated to control the
positional orientation of the proximal
segment and fill bony voids.
• The amount of mandibular
advancement and vertical lengthening
possible with this technique is limited
by the temporalis muscle attachment
and interference of the coronoid
processes on the zygomatic arch.
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95. • Inverted “L” osteotomy.
( Subsigmoid osteotomy )
• Alternate to BSSO
• 5 mm advancement or retraction
can be done--Limitation
The inverted “L” osteotomy (ILO)
can be used to advance the
mandible and vertically lengthen
the ramus, but it may require bone
or synthetic bone grafting to control
the positional orientation of the
proximal segment and to fill the
bony voids between segments. The
use of rigid fixation is
recommended.
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96. With any of the above mandibular ramus procedures,
the preoperative rate of growth can be expected
to be maintained after surgery. Mandibular growth
should not be affected by any of these techniques, provided
that the condylar head is not damaged during surgery. The
vector of facial growth, however, may be altered by a
change in the orientation of the proximal segment and thus
the condyle, similar to moulding of regenerate in D.Og.
The use of rigid fixation will improve long-term stability
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97. •
TMJ & VME
• The TMJs are the foundation for orthognathic surgery. If the
TMJs are not stable and healthy, orthognathic surgical results
may be unstable, with increased TMJ dysfunction and pain as a
result. The TMJs must be appropriately evaluated before
surgery. The most common TMJ disorder seen in orthognathic
surgery patients is the displaced articular disk. Significant
problems can occur when orthognathic surgery is performed in
the presence of untreated disk displacement.
• Pullinger et al demonstrated a higher prevalence of open bite in
DD with reduction and DDN . Out of 614 patients with TMJ
disorders 32 had anterior open bite and 27 / 32 had disk
displacement.
• Riolo et al ( AJO 1987 ) suggested that open bite was positively
associated with TMD and muscle tenderness.
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98. • Kerstens et al ( J cranio Max S ) studied 480 OS patients both
pre and post operatively and found that retrognathic patients
with low and normal angle MPA were more likely to have
preoperative TMJ signs and showed improvement of signs and
symptoms postoperatively.High angle patients with mandibular
retrognathism had highest post surgical incidence of TMJ signs
and symptoms. ( Surgery done BSSO and LF –I).
• Stringert and Worms ( AJO 1986 )compared cephalometric data
from a group of 62 subjects with documented internal
derangements with a sample of 102 subjects from normative
sample. Results indicated an increased proportion of subjects
with "high plane" characteristics and a decreased proportion of
subjects with "low plane" characteristics in the experimental
sample.
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99. Relapse
Tongue will adapt to new environment to both
orthodontic treatment Copey (AJO-85) and
surgical treatment Denison (AngIe-89).
Tongue habit should be corrected by
Myotherapy.
Fixed retainer
Use tongue crib during treatment-to alter tongue
posture and after treatment.
Placing retainer that cover occlusal surface.
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