1. MANAGEMENT OF OPEN-BITE
IN ORTHODONTICS
DR SHEHNAZ JAHANGIR
FINAL YEAR MDS
ORTHODONTICS & DENTOFACIAL ORTHOPAEDICS
1
2. CONTENTS
Introduction
Definition
Problems caused by open bite
Features of open bite
Classification
Etiology
ODI
Diagnosis
Management
In decidous dentition
In mixed dentition
In permanent dentition
2
4. SURGICAL CORRECTION
Anterior max & mand. Subapical osteotomy
Kole modification
Sagittal split ramus osteotomy
Lefort I max.osteotomy
Adjunctive surgical procedures
Genioplasty
Recent advances
Stability and Relapse
Conclusion
References
4
5. INTRODUCTION
• Malocclusion can occur in three planes i.e. sagittal plane,
vertical plane and transverse plane.
• Sassouni & Nanda were among the first to describe the
vertical proportions of face & skeletal characteristics
associated with deepbite & openbite.
• The open bite malocclusion is one of most difficult dentofacial
deformities to treat.
• The complexity of this malocclusion is attributed to a
combination of skeletal, dentoalveolar, functional and habit
related factors.
5
6. DEFINITION
• The Glossary of Orthodontic Terms defines open bite as a
developmental or acquired malocclusion whereby no vertical
overlap exists between maxillary and mandibular anterior or
posterior teeth.
6
7. PROBLEMS CAUSED BY OPEN BITE
• Open bite creates significant problems such as
– Difficulty in speech (dysphonia)
– TMJ disorders
– Functional imbalance
– Bad aesthetics
– Alteration of incisior guidance
– Reduction of normal functional activity
7
8. Features of Open Bite
• Increase in the lower facial height
• Clockwise rotation of the mandible
• Extrusion of molars
• Vertical growth of maxilla
8
9. DENTAL OPEN BITE
• Normal facial features
• No alteration in skeletal pattern
• The open bite is restricted to the
anteriors
SKELETAL OPEN BITE
• Associated with Skeletal
abnormality
• Facial vertical disproportions
• The open bite extends to the
posterior segments as well.
• Backward and downward
rotation of mandible
• Exessive vertical growth of
posterior face
11. CLASSIFICATION OF OPEN BITE
Open bite is classified into
Anterior Open Bite
Posterior Open Bite
Anterior Open Bite is further classified
I) On the basis of whether it is due to epigenetic (or)
environmental factors
a) Skeletal open bite
b) Dental open bite
ii) On the basis of upper and lower Ist molar anterior-posterior
relationship
a) Class I open bite
b) Class II open bite
c) Class III open bite
11
12. • Open bite is also classified on the clinical basis
- Simple open bite
- Complex open bite
- Compound open bite or infantile open bite
- Iatrogenic open bite
12
16. Clinical evaluation based classification
Simple open bite – Cases in which there is
more than 1mm of space between the incisors,
but the posterior teeth are in occlusion
16
17. Clinical evaluation based classification
Complex open bite – Cases in which the open bite extends
from premolars or deciduous molars on one side to the
corresponding teeth on the other side.
17
18. Clinical evaluation based classification
Compound or infantile open bite – Cases in which the bite is
completely open including the molars.
18
21. Anterior open Bite:
Inherited factors
Increased tongue size
Abnormal Skeletal growth pattern
Vertical growth pattern (long face Syndrome)
Vertical Maxillary Excess
Rotation of the palatal plane down posteriorly
Localized failure of development
Cleft lip and palate
Muscle weakness syndrome
21
22. Posterior open bite
Result of infra- occlusion of a segment of posterior teeth.
Lateral tongue thrust or lateral tongue posture
Ankylosed or impacted posterior teeth
Early extraction of first permanent molars
Primary failure of eruption
Arrest of eruption
Hemimandibular hypertrophy
22
23. SKELETAL FACTORS IN THE DEVELOPMENT OF AN OPEN BITE
TYPE:
1. The combination of
excessive development
of the upper mid-face
heights (cranial base to
molars)
a lack of development
of posterior facial
heights (S-Go) results
in the downward and
backward rotation of
the mandible.
23
24. 2. The posterior half of the
palate is tipped
downward, carrying the
molars further downward.
This gives rise to a large
palatomandibular plane
angle.
24
25. 3. Because of the short ramus and the lower palate,
the pharyngeal space is constricted. In order to
breathe, these persons keep their tongues forward.
Further enhanced by the dental open-bite, there is
a tongue-thrusting tendencies.
25
26. 4. When enlarged tonsils are
present, the tongue is
further confined anteriorly.
As the narrow palatal vault
reduces the necessary
space, there is a tendency
towards tongue protrusion.
This, in turn, may be a
factor in the creation of bi-
dental protrusion
26
27. Dento Alveolar Open Bite
The extent of the
dentoalveolar open bite
depends on the extent of
the eruption of the teeth.
Eg: Supraocclusion of the
molars and infraocclusion
of the incisors can be
primary etiologic factors.
27
28. 3. In vertical growth
patterns the
dentoalveolar symptoms
include a protrusion in
the upper anterior teeth
with lingual inclination of
the lower incisors.
28
29. 4. In horizontal growth
patterns, tongue posture
and thrust may cause
proclination of both upper
and lower incisors.
29
30. Dimensional Deviations
1. The total posterior facial
height (S-Go) tends to be
half the size of the anterior
total facial height (N-Me).
30
31. 2. The Lower Anterior Facial
Height exceeds the Upper
Anterior Facial Height.
31
32. 3 The facial breadths tend to
be narrow, giving a long,
ovoid appearance in the
frontal view.
32
33. 5.The ramus is short with
an antegonial notch at
its lower border.
6. The mandibular
symphysis is narrow
antero posteriorly and
long vertically.
7. There is a lack of chin
mental protuberance
development.
33
34. SKELETAL CLASS II OPEN BITE
1. In this type, in some instances,
the rotation of the mandible
may be purely positional. Often
this is due to a downward and
backward rotation of the
mandible.
2. This rotation is associated with
excessive extrusion of the
molars. If these interferences
were removed, the mandible
could be permitted to rotate in
a closing direction, improving
the Class II and the open-bite
patterns simultaneously.
34
35. SKELETAL CLASS III OPEN BITE
1. This combination consists
primarily of an open-bite
with a palatal deficiency or
a large mandible.
35
36. Among the facial deformities, these have probably the worst
prognosis in terms of dentofacial orthopedics.
If correction of this open-bite is attempted by rotating the
mandible in a closing direction, the protrusion of the chin is
increased.
On the other hand, the reduction of the mandibular protrusion
is attempted by rotating the mandible downward and
backward, the open-bite is increased.
36
37. •The Overbite Depth Indicator
(ODI), as described by Kim7 in
1974 has been
•used to assess the vertical
component of malocclusion.
•angle formed by the AB plane to
the mandibular plane combined
with the angle formed by the
palatal plane and the Frankfort
horizontal plane;
•74.58 (standard deviation = 6.078
•ODI increased, there was a
tendency for the overbite to
increase,
•and as the ODI decreased, there
was a tendency toward an anterior
open bite.
•Anteroposterior Dysplasia
Indicator (APDI)- Kim And
Vietas (1978)
•assess the skeletal relationship in
the anteroposterior plane.
•the facial angle, the A-B plane,
and the palatal plane in relation to
the Frankfort horizontal plane
•(Class I) occlusion was found to
be 81.48(SD=3.79
•Smaller APDI values relative to
the mean indicate a Class II
malocclusion,
•while larger APDI values
suggest a Class III malocclusion.
Overbite depth indicator and anteroposterior dysplasia indicator cephalometric
norms for African Americans Samuel et al 2019 Angle Ortho
37
39. Clinical
– Pseudo-open bite (overjet and overbite < 1mm)
– Simple open bite (open bite >1mm)
– Complex open bite (open bite extending from
deciduous molars on one side to the other)
– Compound or infantile open bite (completely
open including molars)
– Iatrogenic open bite (consequence of orthodontic
or surgical treatment)
39
40. Cephalometric
– Dento-alveolar open bite ( depends on the extent
of eruption of the teeth)
» supra eruption of molars,
» infraocclusion of incisors,
» lateral openbite
40
41. –Skeletal open bite
• Excessive anterior facial height but decreased
posterior facial height
41
42. Skeletal open bite
Usually normal
Antegonial arching
Ramus is short
Increased bony angle
Growth pattern is vertical
Upward tipping of the forward end
of the maxillary base
Downward tipping of the posterior
end of the maxillary base
Increased total anterior facial height
with no difference in the cranial base
42
–Mandibular base
–Maxillary base
43. In skeletal open bite the anterior teeth are either
normally erupted or over erupted
In dento-alveolar open bite the anterior teeth are
under erupted due to certain interferences
(certain habits)
43
44. Variations of open bite depending on the inclination
of the maxillary base or palatal plane
Vertical growth pattern
with upward tipping of
the forward end of the
maxillary base
44
45. Vertical growth pattern
with downward tipping of
the anterior end of the
maxillary base.In this
case the open bite is
partially compensated
Horizontal growth
direction with an open
bite cause by upward
and forward tipping of
the maxillary base
(decompensated deep
overbite). 45
47. Management is based on etiology and
localization of malocclusion
• Management in dento-alveolar open bite
–Habit control and elimination of abnormal
perioral muscle function
• Management in skeletal open bite
–During active growth phase
• Redirection of growth
–After active growth phase
• Extraction and orthodontics or
orthognathic surgery
47
48. • Management in combined dento-alveolar
and skeletal open bite
– Combined therapeutic approach is needed to
achieve optimum results.
48
49. • The timing of treatment and
• Determination of growth pattern are
crucial.
49
50. Timing of treatment
It depends on the etiology of malocclusion.
If the causative factor can be eliminated, early
interceptive therapy is indicated; Dysfunctions should
be eliminated as quickly as feasible.
50
51. Skeletal problems can be solved or compensated
at a later age.
If skeletal open bite problems are treated in the
primary dentition years, relapse occurs because of
the continued growth in the original
disproportionate pattern.
A child treated very early, usually needs further
treatment during the mixed dentition and again in
the early permanent dentition to maintain the
correction.
51
52. The child should be treated in the preadolescent years
Malocclusion is extremely severe
Esthetic and the resultant social problems
are substantial
Trauma prone
Combined vertical and anterio- posterior
problems
Asymmetry
For moderately severe skeletal problems treatment
can be done during the adolescent growth spurt
Timing of treatment
52
53. Management
• Based on type of dentition, the management
can be divided into
– Management in deciduous dentition
– Management in mixed dentition
– Management in permanent dentition
53
54. • Management in deciduous dentition
– Dento-alveolar
• Tongue crib, oral screen, reminder appliance, activator,
etc.
• Open bite is usually corrected as soon as the habit is
broken
– Skeletal
• Phase I
– Extra-oral orthopaedic appliances (chin cap)
• Phase II
– Habit control
54
55. • Management of mixed dentition
– Dento-alveolar
• Early mixed dentition
– Screening appliances and habit breaking appliances
• Late mixed dentition
– Multi-attachment fixed appliances
– Extended retention phase
– Swallowing exercises
– Skeletal
• Management depends on severity of malocclusion and
possibility of a DA compensation
55
56. Skeletal (cont.)
The inclination of the maxillary base plays a vital role in the
management. If the jaw bases are divergent, the prognosis is
poor.
If the maxillary base is tipped downward and forward, functional
appliance therapy may be successful.
If the jaw bases are divergent, fixed appliance therapy is indicated
In severe cases, orthognathic surgery with impaction of buccal
segments is performed.
If the lip sealing ability is disturbed, surgical resection of the
mentalis muscle is performed to reduce the ‘golf ball’ chin effect.
Schili insists on surgery after eruption of lower canines to
enhance stability
56
57. • Combined dento-alveolar and skeletal
– Elimination of abnormal perioral function
• Screening and habit breaking appliances, serial
extraction, activators, etc.
– Improvement of the skeletal relationship
• Fixed appliances or orthognathic surgery (severe)
57
58. • Management in permanent dentition
– Multi-attachment, fixed mechano-therapy
– Screening appliances
– Screening appliances with active extrusive force
on incisors (tongue crib with active labial bow)
– Repelling and attracting magnets
– Functional appliances can be used in the retention
phase to prevent over eruption in the posterior
segments
58
59. Management Of Open Bite
• Management of open bite can be majorly
classified as:
–Orthodontic correction
–Surgical correction
–Combination of orthodontic and surgical
correction
59
62. Surgical Correction
Anterior maxillary and mandibular subapical osteotomy
Kole’s modification of subapical osteotomy
Sagittal split ramus osteotomy
LeFort I osteotomy
Adjunctive surgical procedures
The V excision
The Keyhole procedure
Deep Lingual Frenectomy
Genioplasty
TMJ considerations
62
63. Orthodontic Correction
• Habit breaking appliances
– Tongue crib
• Anterior open bite
– A palatal acrylic plate with a horseshoe shaped wire crib and labial
bow
– Crib placed 3 to 4 mm lingual to upper incisors or at gingival 1/3.
• Posterior open bite
– The crib is placed 2-3 mm away from the teeth
– Fixed tongue cribs are also used.
– Reminder appliances
• An acrylic plate in which a bead or a wire mesh is embedded
• Reminds the patient not to go back to the habit
63
64. Vestibular screen
An acrylic shield extending vertically from the
upper labial fold to the lower labial fold and
horizontally from the distal margin of the last
erupted molar on one side to that on the other
Edge to edge bite registered
Achieves proper lip seal, thereby creating a
somatic swallow pattern
Worn at night and 2 to 3 hours during daytime
64
65. Lip exercises along with the appliance
Modifications
Vesitbular screen with breathing holes
Vestibular screen with tongue crib
65
67. • Other methods
– Psychological approach
• Parent counselling
• Patient counselling and motivation
• Dunlop’s Beta hypothesis
– Chemical approach
• Bitter tasting or foul smelling preparation placed on the
thumb or digit
67
68. • Myofunctional appliances
– Activator
• Used to correct anterior open bite.
• Increases salivary secretion, swallowing activity,
muscle contraction and amount of intermittent
forced applied to the tooth..
• Intrusion of molars achieved by loading the cusps
• Extrusion of incisors achieved by loading the lingual
surfaces above the area of greatest concavity and
also with the labial bow above the area of greatest
convexity.
68
70. • A modification, the Elastic Activator similar to
Stockfish’s kinetor was used in the treatment
of anterior open bite by A. Stellzig et.al in
1999.
– The intermaxillary acrylic of the lateral occlusive
zones is replaced by elastic rubber tubes
– Intrusion of both upper and lower posterior teeth
by orthopaedic gymnastics
70
71. The open bite bionator inhibits abnormal posture
and function of the tongue.
Construction bite is as low as possible
The palatal part moves the tongue into a more
posterior position
The labial bow run between the incisal edges of the
upper and lower incisors at the height of correct lip
closure to achieve a competent lip seal
Reduced bulk and full time wear are the advantages
The labial bow’s lateral extensions have a screening
effect.
71
The Bionator
73. The FR –IV is used in the treatment of skeletal open
bite and maxillary protrusion
It has two buccal shields, two lower lip guards, an
upper labial wire, and four occlusal rests.
The occlusal rests prevent eruption of the posterior
teeth.
Lip-seal exercises should be advocated along with
FR-IV.
Modifications:
FR-IV with chin cap.
FR-IV with a tongue crib.
73
FR-IV
75. Consists of simple upper and
lower bite blocks that
engage on occlusal incline
planes and modify them
effectively
Contact between occlusal
bite blocks and posterior
teeth should be maintained
to prevent eruption of the
posterior teeth
75
Twin Block
76. Modifications
Headgear tubes can be attached and high pull traction can be
applied to a modified face bow (concorde) for intrusion of
molars
Vertical elastics (Mills)
Repelling rare earth magnets
Palatal spinner can be added to the upper appliance
76
77. –Robert G. Cash in 1987 used Jasper
jumper to treat open bite
–The Jasper jumper was used to distalize
and intrude maxillary molars
77
Jasper jumper
79. The Multiloop Edgewise Archwire
Technique (MEAW)
– Young H. Kim in 1987 used the MEAW technique
to correct anterior open bite
– This is one of the most effective treatment
modalities for anterior open bite malocclusions
– The MEAW technique lowers the load deflection
rate and allows the tooth to move independently
79
80. It uses double edgewise brackets with 0.018 inch slots with an
auxiliary vertical slot
Archwire used is 0.016 x 0.022 inch rectangular SS wire and there
are five loops on either side
Vertical loop components are centered at interproximal areas and
the horizontal loop components are directed mesially.
Wire used is 2 ½ times more than normal and hence a tenfold
reduction in the load deflection rate.
The curve and reverse curve of Spee in both archwires worsen the
open bite and this is counteracted by using anterior vertical elastics
full time
The completed archwire is treated to about 900 deg F. to increase
resiliency and stiffness
Extraction of second and third molars offers a feasible therapeutic
situation by eliminating the dynamic blocking effect and also
cortical bone
80
84. Modifications Of MEAW
• Haruo Takayama et al, in 1990 used double
key-hole archwire loops in the posterior region
in open-bite with Turner’s syndrome.
• Ahyanenacar et al, in 1996 used 0.016 x 0.022
Niti wires instead of SS wires along with heavy
inter maxillary elastics in the canine region.
84
85. The Tip-edge Technique
• Kesling in 1986 designed the Tip-edge brackets which
are dynamic and upright teeth easily and
automatically with or without intermaxillary elastics.
• No loops are required for uprighting.
• Anteriorly placed class III elastics with Tip-edge
brackets were used to correct anterior open-bite.
• Kim’s philosophy + Tip-edge brackets produced
stable results in a very short period of time.
85
86. Headgears
Headgears have been used to correct open-bite by
molar intrusion.
• Galletto in 1990, used posterior bite blocks in
conjunction with high-pull headgear and archwire
mechanics to correct adult anterior open-bite.
• Roberto Martina et al in 1990, used a cervical pull J-
hook type headgear attached at the anterior part of
the archwire.
• Allison et al in 1994, used a cervical pull headgear
and a lower utility archwire in growing patients.
86
87. High pull headgear to the molar
High-pull headgear to the posterior
maintains the vertical position of the maxilla
and inhibits eruption of the maxillary
posterior teeth.
It is worn 14 hours a day
Force applied is 12 ounces per side.
87
88. High-pull headgear to a maxillary splint
This allows the vertical force to be directed
against all the maxillary teeth– not just the molars.
It has a better maxillary dental and skeletal effect
with good vertical control compared to High pull
headgear to the molar.
88
89. High pull headgear to a functional appliance
with bite blocks.
The functional appliance provides the
possibility of enhancing mandibular growth
while controlling the eruption of posterior
teeth.
Increases the control of maxillary growth.
Improves retention of the functional
appliance.
Produces a force direction near the
estimated center of resistance of the maxilla
The extra oral force:
89
91. The headgear tubes are incorporated into the
bite blocks in the premolar region.
The outer bow must be short or moderate and
bent upwards such that the resultant force
would pass through the center of resistance of
the maxilla
Force of 400gms per side
91
92. Headgears & Elastics
• David Gehring et al in 1998, used a high pull
headgear with vertical elastics to treat class II div.1
cases with anterior open-bite.
• Roy Sabri in 1998, used used a high pull headgear
with class II & vertical elastics, to treat class II div.1
cases with anterior open-bite.
• Smith& Alexander in 1999, used a cervical pull
headgear, Cl.II & Ant. Box elastics, and gingivally
placed brackets to correct Cl.II div.1 sub-division right
open-bite.
92
94. Elastics
• Viazis in 1991, used a combination of upper SS wire,
lower rect. Niti wire & vertical elastics to correct
both ant. & post. Open-bites.
• Rinchose in 1994, used two vertical elastics, one on
either side of the mid-line, extending from a
Kobiyashi hook on the lower centrals to the upper
centals and then to the lower laterals to correct ant.
Open-bite.
94
96. 0.016 x 0.022 upper accentuated-curve and
lower reverse-curve nickel titanium with the
heavy intermaxillary elastics applied in the
canine regions.
JCO 1996 AYHAN ENACAR
96
98. Magnets
Since the introduction of rare earth magnets such as
Samarium Cobalt by Becker in 1970, their use in the field
of Orthodontics has become increasingly popular.
Eugene Dellinger in 1986 was the first to use them to
correct anterior open-bite in his Active Vertical Corrector.
The AVC consists of upper & lower bite blocks with
Samarium Cobalt magnets in stainless steel cases
embedded in them.
The method of action is reciprocal intrusion of the
maxillary & mandibular posterior teeth leading to the
autorotation of the mandible, closure of the open-bite &
reduction of lower anterior facial height.
98
99. • Kalra & Burstone in 1989 introduced a fixed magnetic
appliance which consisted of upper & lower acrylic
splints with Samarium Cobalt magnets in SS cases in
the repelling mode, in open-bite cases.
• Killiardis used magnets in bite-blocks in the
correction of open-bite.
• Noar,Shell & Hunt used Neodymium-Iron-Boron
magnets with an acrylic coating in treating ant.
Open-bite.
99
100. Ali Darendeliler in 1995 used the MAD IV
(Magnetic Activator Device IV ) to correct anterior
open-bite.
The MAD IV consists of anterior attracting &
posterior repelling magnets.
It consists of removable upper & lower acrylic plates,
each containing 3 cylindrical Neodymium magnets
coated with stainless steel. The attracting force of
the anterior magnets is 300gm & the repelling force
of the posterior magnets is also 300gm.
100
101. In the mixed & permanent dentition, the plates
are retained mechanically but, in the late
mixed dentition, mod. Adams clasps &
Torquing springs give added retention.
MAD IV a: used in cases where the max. ant.
Segment is vertically overdeveloped.
MAD IV b: used when an additional extrusive
effect is required in the max. ant. region.
MAD IV c: used when only anterior extrusion is
needed.
101
104. IMPLANTS
• Beth Prosterman et al. In 1995 has
described the use of implants for correction
of open bite.
• He concluded that since osseo integrated
titanium implants show remarkable
resilience to pressure they can prevent
extrusion of mandibular post. teeth thereby
preventing increase in ant. facial height
• He advocated the use of implants in
conjunction with fixed appliances to correct
ant. open bite. 104
106. TCA
Viazis in 1993 described the Thumb sucking /
tongue thrusting / tongue posturing correction
appliances.
The TCA consists of a palatal wire that is
inserted in the upper lingual molar sheaths &
carries over to the lower incisors ending 1-2
mm. above the labial surface.
The TCA prevents the habits by blocking the
tongue from the ant. teeth.
The TCA should be worn for atleast 3 months.
106
108. SAS
Mikako Umemori et al. in 1999 described the SAS
(Skeletal Anchorage System for open bite
correction).
The SAS consists of a titanium mini plate implanted
in the maxilla or mandible.
The mini plates were fixed in the buccal aspect of
the bone at the apical region of first & second
molars on both sides.
Elastic threads were used as a source of orthodontic
force for intrusion ( intrusion of 3-5 mm. achieved
with SAS ).
108
109. • Advantages of SAS :
No serious side effects.
Simplified treatment mechanics.
Shortened treatment period.
Minimum discomfort.
Control of the level of occlusal plane.
109
110. THERA SPOON
• Bennett et al. In 1999 described the efficacy of
open bite treatment with Thera spoon
• Compared to the Tongue crib where there is
complete closure of ant. open bite &
significant extrusion of the incisors , the Thera
spoon does not show remarkable results.
110
111. SURGICAL CORRECTION
ANTERIOR MAX. & MAND. SUB-APICAL OSTEOTOMY.
KOLE MODIFICATION OF SUB-APICAL OSTEOTOMY.
SAGITTAL SPLIT RAMUS OSTEOTOMY
LE FORT-I MAXILLARY OSTEOTOMY
ADJUNCTIVE SURGICAL PROCEDURES
THE ‘V’ EXCISION
THE KEYHOLE PROCEDURE
DEEP LINGUAL FRENECTOMY
GENIOPLASTY
TMJ CONSIDERATIONS
111
112. SURGICAL CORRECTION
• Hulliten in 1849, was the first to surgically
correct an ant. open bite.( Ant. Mand. Sub-
apical Osteotomy ).
• Cohn-stock in 1921, introduced Ant. Max.
Osteotomy which was modified by
Wassmund, Wunderer & Cupor.
• Schuchardt introduced Post. Max.
Osteotomy as a two-stage procedure which
was modified to a single-stage procedure
by Kufner.
112
113. • Limberg in 1925, introduced Closed Sub-
condylar & Open oblique Osteotomy.
The present-day surgical techniques to
correct open bite involves, Max. surgery for
ant. extrusion & post. intrusion, and Mand.
surgery to elevate the incisor segment. The
choice of the appropriate surgical technique
requires careful diagnostic evaluation.
113
114. ANTERIOR MAX. & MAND. SUB-
APICAL OSTEOTOMY
• INDICATIONS FOR MAXILLARY ASO
A small open bite with minimal tooth
exposure, lip incompetance , good naso-
labial angle & adequate lower ant.facial
height.
An unaesthetic edentulous appearance
due to concealed maxillary incisors.
114
115. • INDICATIONS FOR MAND. ASO
Ant. open bite due to reverse curve in
the mandibular arch.
Transverse max.-mand. harmony &
good aesthetic balance between upper lip
& max. ant. teeth.
After surgery the max. & mand.
Ant. Segment are immobilised for 5-6
weeks. Relapse potential is very minimal.
115
116. KOLE MODIFICATION OF SUB-APICAL
OSTEOTOMY
INDICATIONS
Mandibular prognathism with ant. open bite.
Severe reverse curve.
Excessive chin height.
Functional post. occlusion.
Satisfactory lip-tooth relationship & no transverse
deficiency in maxilla.
The principle disadvantage here relates
unpredictable soft tissue profile changes & chin height
changes.
116
117. SAGITTAL SPLIT RAMUS
OSTEOTOMY
This surgery can be performed in both extraction &
non-extraction cases.
It is indicated in open-bite cases with severe mand.
deficiency or prognathism.
It is usually done along with maxillary osteotomy to
minimize relapse.
If performed separately, posterior overcorrection
with an interocclusal splint, supra-hyoid myotomy
and cervical collar should be considered to prevent
relapse.
117
118. LE FORT-I MAXILLARY OSTEOTOMY
This surgery is indicated in open-bite cases with:
• High & constricted palatal vault.
• Lip incompetence.
• High mand. plane angle.
• Increased distance between the palatal root
apices & the nasal floor.
118
119. • If the inferior turbinates are interfering
with the repositioning of the maxilla, they
are trimed with a Mayo scissors (Adjunctive
Inferior Turbinectomy ).
• Stabilization of the maxilla is done with
trans-osseous 26-guage wire sutures.
• If there are bony defects after surgery, bone
grafts from the Iliac crest or Hyroxyapatite
crystals are used to bridge them.
119
120. ADJUNCTIVE SURGICAL
PROCEDURES
Adjunctive surgical procedures have to be
performed to combat either, a large tongue
or a tongue with abnormal function, which
cause open-bite or even its recurrence.
To correct True, Relative or Functional
Macroglossia the following procedures are
performed:
• The V excision for partial glossectomy.
• Keyhole procedure for partial glossectomy.
• Deep lingual frenectomy. 120
121. GENIOPLASTY
Fridrich et al. in 1997 described various
Genioplasty stratergies for anterior facial
vertical dysplasias.
Different types of Genioplasty:
• Sliding advancement genioplasty
• Genioplasty with parallel ostectomy
• Genioplasty with down graft
• Genioplasty with anteriorly tapered ostectomy
• Sliding setback genioplasty 121
122. Fridrich stated that failure to recognise
vertical dysplasia of the mandible will lead
to post-op mentalis strain.
He concluded that, in vertical dysplasias,
genioplasty gives good esthetic results
with functional harmony.
122
123. • Two Types of Vertical Excess
• ‘vertical excess with anterior open bite’ and
‘vertical excess with normal anterior
overbite’.
• Molar intrusion itself is enough for
correcting the vertical excess with anterior
open bite, because the opened anterior teeth
will be automatically seated down by the
closure of the mandibular plane.
• 1 mm molar intrusion will close 2-3 mm
overbite in the anterior teeth
RECENT ADVANCES
124.
125. Stability and relapse?
• Is early treatment indicated?
• Is the stability of open bite treatment a clinical problem?
– Lopez-gavito1985 - 65% treatment stability
35% relapse
– Huang G 2002- 80% treatment stability
20% relapse
– Katsaros C, Berg 1993- 75% treatment success
The resting posture of the tongue is more important than
its function during swallowing
1. Shapiro PA. Stability of open bite treatment. American journal of orthodontics and dentofacial orthopedics.
2002 Jun 1;121(6):566-8.
2. Huang G. Long-term stability of anterior openbite therapy: a review. Semin Orthod, in press 2002
126. conclusion
• Open bite has multiple aetiologies and accurate diagnosis is the key to determining
the best management strategy for the individual patient.
• Many open bites will resolve spontaneously before the age of 12 due to ceasing of
digit habits and maturation in the swallowing pattern.
• Older patients with an OB should have the high risk of relapse of treatment
explained and, where there are no other anomalies to be corrected, thought should be
given to accepting the malocclusion, particularly if the open bite is small and there
are no functional problems.
• Treatment options include attempting to redirect growth using myofunctional
appliances, use of conventional fixed appliances with highpull headgear and/or
vertical anterior elastics, and a joint orthodontic/ surgical approach for skeletal open
bites.
• Long-term retention is recommended.
127. REFERENCES
• Greenlee GM, Huang GJ, Chen SS, Chen J, Koepsell T, Hujoel P. Stability of treatment for
anterior open-bite malocclusion: a meta-analysis. American journal of orthodontics and
dentofacial orthopedics. 2011 Feb 1;139(2):154-69.
• Ngan P, Fields HW. Open bite: a review of etiology and management. Pediatric dentistry.
1997;19(2):91.
• Justus R. Correction of Anterior Open Bite with Spurs: Long-Term Stability. World Journal of
Orthodontics. 2001 Sep 1;2(3).
• Burford D, Noar JH. The causes, diagnosis and treatment of anterior open bite. Dental update.
2003 Jun 2;30(5):235-41.
• Epker BN, Fish LC. Surgical-orthodontic correction of open-bite deformity. American Journal
of Orthodontics and Dentofacial Orthopedics. 1977 Mar 1;71(3):278-99.
• Paik CH. Molar Intrusion Using TADs: The Key Element to Correcting Anterior Open Bite
and/or Vertical Excess Problems. Oral presentation. 2013.
Editor's Notes
Pseudo-open bite – Cases with an overjet combined with an open bite of less than 1mm.
Simple open bite – Cases in which there is more than 1mm of space between the incisors, but the posterior teeth are in occlusion.
Complex open bite – Cases in which the open bite extends from premolars or deciduous molars on one side to the corresponding teeth on the other side.
Compound or infantile open bite – Cases in which the bite is completely open including the molars.
