DR MOHAMMED ASLAM V DEPARTMENT OF ORTHODONTICS

1. Mohammed Aslam
2nd
year P G student
Department of orthodontics
1

2.  Introduction
 Classification
 Etiology
 Diagnosis
 BIOMECHANICS
 Management
◦ Orthodontic
◦ Surgical
 Retention and Relapse
 References
2

3.  Definition: Open bite is the failure of a tooth or
teeth to meet their antagonist in the opposite arch.
 Open bite is a condition of malocclusion wherein
there is an overlap between the maxillary and
mandibular dentition.
3

4.  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
4

5.  Increase in the lower facial height
 Clockwise rotation of the mandible
 Extrusion of molars
5

6.  Open bite is classified :
◦ On the basis of region involved as
 Anterior Open Bite
 Posterior Open Bite
◦ On the basis of etiological factors as
 Skeletal Open Bite
 Dental Open Bite
◦ On the basis of Molar Relationship as
 Class I Open Bite
 Class II
 Class III
6

7.  On the basis of clinical evaluation as
◦ Simple (occurs between the incisors)
◦ Complex (extends from premolars or deciduous molars
from one side to the other)
◦ Compound/Infantile open bite (completely open including
the molars)
◦ Iatrogenic Open Bite (consequence of orthodontic or
surgical therapy)
7

8.  Can be classified in to
◦ Epigenetic
◦ Environmental
 OR
◦ Disturbances in the eruption of teeth or alveolar growth
(ankylosed teeth)
◦ Mechanical interference with eruption and alveolar
growth (thumb or digit sucking)
◦ Vertical skeletal dysplasias
8

9.  Posture, morphology and size of the tongue
 Skeletal growth patterns of the maxilla and the
mandible
 The vertical relationship of the jaw bases
9

10.  Abnormal function
◦ Thumb or digit sucking habit
◦ Tongue thrusting habit
 Improper respiration
◦ Mouth breathing
10

11.  Thumb or digit sucking habit
◦ This is one of the most common habits seen in children.
◦ The habit is quite reversible till the age of 3or4
◦ Beyond this age, this habit becomes the cause of many
malocclusions.
◦ Causes of the habit
 Sigmund Freud- emotional security derived from the oral
phase of psychological development of first 3 years of life
11

12.  Tongue thrust habit
◦ Infantile / visceral swallowing is the physiological basis
for the neonate/infant to create a proper lip seal during
suckling. When the deciduous teeth erupt, the pattern of
swallowing changes to adult/mature swallow. If the
visceral swallow persists after the 4th year of life, the
habit is called retained infantile swallow or tongue thrust.
12

13.  Sean and Wise (1950) stated that digit sucking led to thumb
sucking
 Benjamin’s theory- the basis of thumb sucking is found in the
physiological rooting reflex of infancy where the infant
reflexively sucks the nipple of the breast, a teat of a feeding
bottle, or a finger.
 Psychological labilty- thumb sucking is a sign of lack of
parental love or fundamental psychological insecurity.
 Learned behaviour: children learn the habit from siblings or
toddler friends.
13

14.  Etiology of tongue thrust
◦ Genetic factors
◦ Learned behaviour
◦ Maturational factors
◦ Mechanical restrictions
 Macroglossia
 Constrictive dental abscess
 Adenoid hypertrophy
 Neurological disturbances
 hyposensitive palate
 Moderate motor disability
◦ Psychogenic factors
14

15.  Classification of tongue thrust activity (Bohr &
Holt):
◦ Tongue thrust without deformation
◦ Tongue thrust causing anterior deformation
 Anterior / Simple Open Bite
◦ Tongue thrust causing buccal segment deformation
with a posterior open bite (lateral tongue thrust)
◦ Combine tongue thrust causing both anterior and
posterior open bite (complex open bite)
15

16.  Mouth breathing habit
◦ The mode of respiration influences the posture of the
jaws, the tongue and to a lesser extent, the head. Hence
mouth breathing can result in altered jaw and tongue
posture thereby altering the oro-facial equilibrium leading
to malocclusion.
16

17.  Classification of mouth breathers
◦ Obstructive
 Complete or partial obstruction of the nasal passage
◦ Habitual
 Unconsciously performed act whereby breathing occurs
despite removal of obstruction
◦ Anatomic
 Lip morphology does not permit complete closure of the
mouth
17

18.  Clinical features of mouth breathers
◦ Long and narrow face
◦ Narrow nose and nasal passage
◦ Short and flaccid upper lip
◦ Contracted maxillary arch
◦ Flaring of incisors
◦ Anterior marginal gingivitis
18

19.  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 together)
◦ Compound or infantile open bite (completely open
including molars)
◦ Iatrogenic open bite (consequence of orthodontic or
surgical treatment)
19

20.  Cephalometric
◦ Dento-alveolar open bite ( depends on the extent of
eruption of the teeth)
 Vertical growth pattern
 protrusion of upper anterior, lingual inclination of lower incisors
 Horizontal growth pattern
 upward and forward tipping of the maxillary base
20

21. ◦ Skeletal open bite
 Excessive anterior facial height but decreased posterior
facial height
 Mandibular base
 Usually normal
 Antegonial arching
 Ramus is short
 Increased bony angle
 Growth pattern is vertical
21

22.  Maxillary base
 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
 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)
22

23. Anterior elastics
An extrusion arch (in blue) tied
to a rigid anterior segment
creates a one-couple force
system that generates a single
force (F) anteriorly (in green).
The moments (M) generated
(in blue) are counteracted by
another set of moments (in
red) using elastics (yellow) as
shown. This example is
assuming that the center of
resistance of the posterior
segment is between the roots of
the premolars
23

24. A case report based on
Figure illustrating the
application of elastics and
an extrusion arch in the
successful management of
an open-bite
malocclusion.
Note how the judicious
application of elastics in
combination with the
extrusion arch results in
the
correction of the open
bite
and also provides the
necessary overcorrection
for
long-term retention
24

25. 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
25

26.  Management in combined dento-alveolar and
skeletal open bite
◦ Combined therapeutic approach is needed to achieve
optimum results
26

27.  The timing of treatment and determination of
growth pattern are crucial. Based on type of
dentition, the management can be divided into
◦ Management in deciduous dentition
◦ Management in mixed dentition
◦ Management in permanent dentition
27

28.  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
28

29.  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
29

30. ◦ Skeletal
 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
30

31.  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)
31

32.  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
32

33.  Management of open bite can be majorly
classified as:
◦ Orthodontic correction
◦ Surgical correction
◦ Combination of orthodontic and
surgical correction
33

34. Correction oral habits: Tongue thrust
(Neuromuscular re-education), Thumb
sucking, Mouth breathing
34

35.  Habit breaking appliances
◦ Tongue crib
◦ Reminder appliance
◦ Vestibular screen
◦ Others
 Myofunctional appliances
◦ Activator
◦ Bionator
◦ FR-IV
◦ Twin Block
◦ Jasper jumper
35

36.  Multiloop edge wise arch wire technique
 Tip edge technique
 Headgears
 Elastics
 Magnets
 Implants
 Posterior bite blocks
 TCA
 SAS
36

37.  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
37

38.  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
38

39.  Patients with tongue
thrusting can be treated
 effectively in the same
manner as that used for
 patients who suck on a
thumb or finger
 ,although different
appliances, such as the
 habit appliance with
lingual spurs or cribs ,
 have been suggested, In
one
 study, immediately after
crib placement the tip
 of the tongue was
positioned posteriorly
 during all stages of
deglutition.
 This altered tongue
posture aided in the
 correction of an anterior
open bite through an
 increase in overbite of
3.6-m
Tongue spurs
39

40.  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
◦ Lip exercises along with the appliance
 Modifications
 Vesitbular screen with breathing holes
 Vestibular screen with tongue crib
40

41.  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
41

42.  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..
 Forward positioning of the mandible not necessary
 Open bite correct by selective trimming
 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.
42

43. 43
 To “ close the V” between
Upper and lower dental arches
By depressing the posterior
Maxillary segments with the
Activator in a manner analogous
to that of orthognathic surgery

44. 44

45.  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
Activator
45

46. ◦ 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.
The Bionator
46

47. ◦ 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.
FR-IV
47

48. ◦ 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
◦ 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
Twin Block
48

49. ◦ Robert G. Cash in 1987 used Jasper
jumper to treat open bite
◦ The Jasper jumper was used to
distalize and intrude maxillary molars
Jasper jumper
49

50. ◦ 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
50

51. ◦ 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.
51

52. ◦ 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
52

53. 53

54. 54
Typical tip back bends of 3-5 degrees are given on each teeth
Elastics are placed between the loops that lie mesial to
opposing cuspids
Recommended elastic size is 3/16inch heavy,with a force
approximately 50 grams when the jaw is closed

55.  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.
55

56.  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.
56

57. 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.
57

58.  Center of resistance in midfacial complex
 1,Alveolar process
 2,Maxilla
58

59.  Direction of forces passes behind both alveolar
and skeletal centers of resistance,producing
clockwise rotation of maxila and maxillary
dentition
59

60. 60
Direction of forces passes between alveolar and
skeletal centers of resistance,producing clockwise
rotation of maxilla and counter clockwise rotation of
maxillary dentition

61.  Direction of force passes above both alveolar and
skeletal centers of resistance,producing
counterclockwise rotation of maxilla and maxillary
dentition
61

62. Chincup with the force vector directed to the condyle
Dentoalveolar comparative study between removable and
fixed cribs,associated to chincup,in anterior open bite
treatment
Fernando cesar,Renato rodrigues,J Appl Oral Sc,july14,2011
62

63.  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.
63

64. 64

65. Class II orientation
Class III orientation
65

66. For mild open-bite malocclusions (1 to 3 mm),
placing step bends and meticulous bracket
positioning
can help reduce the open bite
without any significant side effects. In this patient,
the anterior brackets were placed more gingivally
as compared to the
posterior brackets, to aid in correction of the open
bite
66

67.  Aids in the improvement of class I cuspid
intercuspation and increasing the overbite
relationship anteriorly by closing open bites in the
range of 0.5mm to 1.5mm
 They extend from upper cuspid to lower cuspid
and first bicuspid teeth
67

68.  Intermaxillary elastics from the posterior teeth
have a vertical force vector which extrudes these
teeth and can further open the posterior vertical
dimension
 Class II elastics from molar to molar should not be
utilised untill these teeth are well anchored in
buccal cortical bone
 If class II or classIII elastics are required,they
should be attached to premolars rather than
molars
68

69. 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.
69

70.  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.
70

71.  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.
71

72. 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.
72

73. 73

74. 74

75. 75

76.  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.
76

77. 77

78.  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.
78

79. 79

80.  The skeletal anchorage system was developed by
umemori and Sugawara
 Appliance design:consist of titanium
miniplates,which are stabilised in the maxilla or
mandible using screws
 The earlier of these miniplates where the
conventional surgical miniplates,which are used
by oral surgeons for rigid fixation
80

81.  The recent versions of these miniplates have been
modified for attaching orthodontic elastomeric or
coil springs
 Different designs of miniplates are available and
this fact offers some versatility in placing the
implants in different sites
81

82.  The ‘L’shaped miniplates have been the most
commonly used ones,while the ‘T’shaped ones
have been proposed for usage while intruding
anterior teeth
 The screws used for fixing the miniplates are
usually 2-2.5mm in diameter
82

83.  Titanium miniplates were implanted after LA with
intravenous sedation
 First,a mucoperiosteal incision was made at the
buccal vestibule directly under first or second
molar
 The mucoperiosteal flap was then elevated and
surface of cortical bone at apical region of the
molar was exposed
83

84.  An ‘L’shaped miniplate was adjusted to fit the
contour of each cortical bone surface and was
fixed by bone screws of length 5 or 7mm,with the
long arm exposed to oral cavity from the incised
wound
84

85. 85
• The implant was placed such that it did not interfer with
mandibular movement.
• All of the miniplates were transfixed at the region of the buccal
vestibule.
• Loading was done after wound is healed.

86.  The implant was placed such that it doesn’t
interfere with mandibular movement
 All of the miniplates were transfixed at the region
of the buccal vestibule
 Loading was done after wound is healed
86

87.  The shape of miniplate can be adjusted to the
type of tooth movement.i.e,intrusion of
molars,incisors etc and based on thickness of
patients bone
 Position of miniplate can be adjusted during
treatment
87

88. 88
It can be placed without destroying the teeth or bone The
anchor plates are monocortically placed at the piriform
opening rim, the zygomatic buttresses, and any regions
of the mandibular cortical bone.
The anchor plates work as the onplant and the screws
function as the implant, SAS enables the rigid anchorage
that results from the osseointegration effects in both the
anchor plates and screws All portions of the anchor
plates and screws are placed outside the maxillary and
mandibular dentition, so the SAS does not interfere with
tooth movement

89. 89
Intusion of lower molar for correction of open bite. Intrusion
of the lower molars was achieved with the application of
elastic orthodontic force on the SAS , Lingual crown
torque was applied to the lower molars with Burstone’s
precision lingual arch to avoid buccal flaring during
intrusion .

90. 90
A)L-shaped miniplate for intrusion of molars
B) L-shaped for distal movement of molars
C) Y-shaped intrusion and distalizaton of maxillary molars
D) Straight miniplate for intrusion of molars

91.  Advantages of SAS :
No serious side effects.
Simplified treatment mechanics.
Shortened treatment period.
Minimum discomfort.
Control of the level of occlusal plane.
91

92.  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.
92

93.  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.
93

94.  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.
94

95.  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.
95

96.  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.
96

97.  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.
97

98. 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.
98

99.  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.
99

100. 100
1.Horizontal incision:through
mucoperiosteum in the anterior
region,extending from premolar to
premolar
2.Soft tissues of maxilla and nasal
floor are carefully reflected,
3.Osteotomy is performed from
lateral-inferior corner of piriform
aperture ,parallel to the ridge and
posterior to pterygomaxillary suture.
4.Maxilla is mobilised with manual
pressure and repositioned inferiorly.

101. 101
5.Bone from ileum is inserted into
the space
6.Mobilised maxilla and grafts are
secured with interosseous sutures at
piriform rims and
zygomaticomaxillary buttress.

102. 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.
102

103. A ‘V’ shaped excision is made from the front of the
tongue, lateral to the midline & extending
posteriorly in nearly a straight line, converging at
the midline at about 4mm from the Circumvallate
papillae.The dorsum of the tongue is closed by
layers using 3-0 & 4-0 chromic sutures & the
ventral surface is sutured by one layer.
103

104. A Keyhole shaped mass of muscle is excised when the
tongue is too large in the molar area and the ant. fourth
is nearly normal.
The ant. incision begins at the tip of the tongue and
extends posteriorly until it reaches the expanded part of
the keyhole begins. The posterior incision curves
laterally and forward and then towards the midline until it
joins the posterior end of the ant. incision.
104

105. A mirror image incision is made through its opposite
side.The posterior incision should taper like a funnel to
avoid any injury to the Lingual artery, nerve, vein, &the
Hypoglossal nerve.
After surgery the jaws must be immobilised so that the
mouth has a fixed volume and also act as a splint.
Tongue excercises are advocated after the 14th post-op
day.
105

106.  Deep lingual frenectomy with ‘Z’ plasty is indicated in
Ankyloglossia or Functional macroglossia where the tongue
does not adapt after ortho. or surgical treatment.
 A linear excision of the mucosal portion of the thickened
frenum is made(care-submandibular duct opening). The
dissection of the fibrosed Genioglossus extends posteriorly
until desired amount of mobility is achieved. Excercises
should be advocated till about 2 months after surgery.
106

107.  Incision half way the depth of vestibule and extended to
canine region bilaterally.
 Periosteum left intact on the inferior border
 Line of osteotomy should be 5 mm below canine root &
10 to 15 mm above the inferior border & 5 mm below the
lowest mental foramen
107

108.  Fragment stabilized by
 unicortical or bicortical wires
 bone plates
 prebent chin plates
 lag screws
108

109. The status of the TMJ is of great importance before
surgery, because the movements associated with
surgery increase pressure in the joint until the muscles,
soft tissues & dento-osseous structures readapt.
Hence, if pre-existing TMJ disorders are carefully assesed
and appropriately managed, the TMJ is stable after the
surgery is performed.
109

110. The main etiological factors responsible for relapse after ortho
correction are:
 Latent vertical growth of the face.
 The role of the tongue.
The main etiological factors responsible for relapse after
surgical correction are:
 Mandibular musculature
 Incompletely understood biomechanical factors influencing the
Elevator group & Suprahyoid group of muscles.
110

111. The success of treatment depends upon the ratio:
Magnitude of improvement
Success = Magnitude of relapse
Wick Alexander stated that retention begins with
Diagnosis & Treatment planning.
‘Begin with the end in mind’ should be the philosophy of
treatment.
111

112.  Upper and lower border wiring of mandible
 Steinmann pins to stabilise the maxilla
 Skeletal wire fixation(circumzygomatic and
circummandibular wires)
 Rigid fixation
112

113. RETENTION AFTER ORTHODONTIC CORRECTION :
Criteria to begin retention are :
 Coincidence of Centric relation& occlusion.
 Class I cuspid relation.
 Maintenance of mand. cuspid width.
 Interincisal angle close to normal.
 Normal ant. Overbite & Overjet.
 Normal Buccal Overjet.
113

114. Criteria:
 Levelled max. & mand. arches.
 All spaces closed & all rotations eliminated.
 Roots parallel near extraction sites.
 Posterior cusps may or may not be settled.
114

115. Active retention normally utilizes :
 A maxillary wraparound retainer and a mandibular
3x3 bonded retainer.
 A full coverage clear acrylic appliance.
 In conjunction with myofunctional therapy, tongue
position excercises are advocated.
115

116. John Sheridan in 1997, described the Force
Amplified System for corrected open-bite.It involves the
use of conventional max. & mand. cuspid to cuspid
bonded lingual retainers, low-profile bonded lingual
Caplin hooks and intraoral elastics. The retainers are
bonded to each tooth to distribute the elastic forces.
116

117. 117

118. conclusion
The treatment of open bite remains a challenge to the
clinician, and careful diagnosis and timely intervention
will improve the success of treating this
malocclusion.The recent trend of combining
orthodontic and surgical methods to manage open
bite,which is a multi factorial problem has been
successful.Lets hope this combination asserts
enough stability in the management of open bite and
similar conditions.
118

119. REFERENCE
•Orthodontics principles and practice,
T.M.Graber,3rd
edition,1988
•Orthodontics and dentofacial orthopedics,
McNamara and Brudon,1st
edition,2001
•Biomechanics and Esthetic Stratergies in Clinical
Orthodontics,R Nanda
•Clinical biomechanics,seminars in orthodontics
March 2001,vol.7,no.1
119

120.  Profit WR, Ackerman JLA systematic approach to
orthodontic diagnosis and treatment planning.
 Graber TM and Swain : Orthodontic concepts &
techniques
 William R. Profit , Raymond P White - In surgical
orthodontic treatment
 Applications of orthodontic mini implants;Jong suk lee
 Temporary anchorage devices in orthodontics-Ravindra
nanda
 Johan P Reyneke – Essentials of orthognathic surgery
120

121. THANK YOU
121