preorthodontics for different types of severe malocclusion is explained

1. Surgical orthodontics
BY
Prof dr Maher Fouda
Faculty of dentistry
Mansoura Egypt

2. Orthognathic surgery is
indicated for those patients
seeking changes in aesthetics
and function of a magnitude
that is not possible with
orthodontics alone.

3. patients seeking changes in aesthetics and function

4. People today usually recognize irregular teeth or obvious jaw
deformities and seek treatment from an orthodontist, who can
improve teeth alignment, function and facial aesthetics. More
severe deformities that cannot be addressed with orthodontics
alone will require a combination of surgical and orthodontic
corrections and are called dentofacial deformities.

5. These deformities can affect facial aesthetics and
function in several ways and would require combined
orthodontic and orthognathic surgical treatment.

6. Several factors presenting either collectively or individually
may indicate the need for combined orthodontic and surgical
treatment. They include impaired mastication,
temporomandibular pain and dysfunction, oral respiration due
to lack of lip competency, impaired speech and susceptibility to
caries and periodontal disease

7. Although the functional impediment is important, the most
common reason for patients seeking surgical correction and
the most important indication of the need for orthognathic
surgery are usually the psychosocial effects resulting from the
unaesthetic appearance from the dentofacial deformity.

8. Because of rapid advances in both orthodontics and maxillofacial surgery, it
is now possible to treat patients with dentofacial deformities to produce
outstanding results that are aesthetically and functionally efficient. This, with
the advent of modern computing skills and with the availability of more
reliable video and computer imaging softwares, makes it not only possible
for the surgeon and the orthodontist to interact better but also
facilitates the patient to perceive the outcome of the treatment
procedure, making the patient a partner in the treatment planning
processes.

9. Ackerman and Proffit1 have further recommended that the clinician might
ignore the limitations of the soft tissue in guiding the treatment planning
processes.
These constraints include the pressure exerted on the teeth by the
surrounding soft tissue envelope and the tongue, the temporomandibular
joint including the muscles that play a major role in function and the
periodontal apparatus. Superimposed on all these is the dynamic soft tissue
integrity of the entire face.

10. There are only three alternatives for treating patients with severe
skeletal or dentofacial deformity.
1. Growth modification in a growing child: Although recent outcome
studies of growth modification using orthopaedic forces and functional
appliances are skeptical about the quantum of additional growth that
can be obtained by using this approach, it is still a popular choice
because the direction and expression of growth can be reasonably
modified .

11. Case VP. Growth modifications in a growing child with a retrusive mandible. (A and B) Pretreatment
facial photographs. (C and D) Pretreatment intraoral photographs. .

12. (E and F) Fixed functional device to modify mandibular growth. (G and H) Post-
treatment intraoral photographs. (I and J) Post-treatment facial photographs.

13. 2. Orthodontic camouflage: In non-growing
individuals, where the skeletal dysplasia is not
very severe, the axial inclination of the teeth can
be modified to mask the severity of the underlying
malocclusion.

14. Case AR. Orthodontic camouflage treatment in a
non-growing patient. (A) Pretreatment frontal
view. (B) Profile view. (C and D) Occlusion.

15. (E and F) The dentition was compensated to camouflage the skeletal
malocclusion. (G and H) Post-treatment occlusion reveals good
reduction in overjet with molars in Angle Class II and canines in
Class I relationship. (I and J) Post-treatment facial view revealing

16. 3. Orthognathic surgery: Once growth is complete,
orthognathic surgery in conjugation with orthodontics
becomes the only option to correct the severe jaw
discrepancy. It is indicated in those patients who have
completed growth phase, in whom growth modification
becomes unviable or in those patients with severe skeletal
discrepancy wherein orthodontic camouflage will not mask the
severity of the skeletal disproportion.

17. Case EN (21 years 4 months). (A and B) Facial view prior to
treatment showing short vertical facial height and anteroposterior
deficiency of the mandible. (C and D) Pretreatment occlusion
revealing 100% deep overbite and increased overjet. (E and F)
Presurgical orthodontic preparation to decompensate the dentition

18. (E and F) Presurgical orthodontic preparation to decompensate the
dentition. (G and H) Occlusion at the completion of treatment. (I and J)
Facial view at the completion of mandibular advancement surgery; note
the increase in facial height, reduction in facial convexity and

19. While the choice between growth modification and orthognathic
surgery depends upon the growth status of the individual, the choice
between camouflage and combined orthodontics and orthognathic
surgery depends not only on the severity of the jaw discrepancy but
also on other aesthetic parameters. Ackerman and Proffit4 have
enumerated some common denominators of relative dentofacial
attractiveness or unattractiveness, which can be used as a guideline to
decide between surgery and camouflage.

20. These parameters include the following:
1. It is permissible to procline the upper and lower incisors in patients who
have a large nose or a large chin, provided the labiomental fold does not
become excessive.
2. Moderate mandibular deficiency is well accepted by the lay public, and
the mandibular deficiency can be camouflaged by orthodontic treatment,
thereby avoiding mandibular advancement.

21. 3. The prominence of the upper lip is influenced by the position of
the upper incisors. Retracting of maxillary incisors reduces the
prominence of the upper lip, and an important guideline for
orthodontist is that the maxillary incisors should not be retracted to
a point that the inclination of the upper lip to true vertical line (TVL)
becomes negative. Hence, in patients who already have a retrusive
upper lip, it is better to procline the incisors, even if it involves
orthognathic surgery to correct the malocclusion.

22. 4. Displaying moderate amount of gingiva adds to the attractiveness of the
smile. Orthodontic camouflage should not be undertaken, if the quantum of
incisor retraction will lead to excessive gingival display. Orthognathic surgery
would be a better option in patients with vertical maxillary excess.
5. Patients who have lower lip trap, resulting in a curled or everted lower lip,
can often be treated with orthodontics alone by retracting the upper incisors.

23. 6. A concave profile with thinning of upper lip and lack of
vermilion show is an unaesthetic trait and can be
corrected by proclining the upper incisors, as
proclination of upper incisors will lead to creating fuller
lips that is perceived to be more attractive.
.

24. 7. While moderate midface deficiency can be camouflaged with
orthodontics, severe midface deficiency or severe mandibular
prognathism creates unattractive lip position and affects throat
form. These conditions are best addressed by surgery and
orthodontics

25. 8. Bidental proclination is an unaesthetic trait resulting
in excessive lip protrusion; extraction of premolar and
orthodontic retraction of incisors will often result in
dramatic reduction of lip protrusion.

26. In general, patients in whom growth is completed, with a
reverse overjet of greater than 3 mm, or Class II patients
with an overjet of greater than 10 mm, a mandibular body
length of less than 70 mm or a facial height of greater
than 125 mm can be treated only by orthognathic surgery.

27. ORTHODONTIC PREPARATION
Patients with dentofacial deformity have dentoalveolar
compensation to mask the skeletal imbalance, and this
is nature’s accommodation to facilitate function.

28. In Class II skeletal deformity, the nature of the dentoalveolar
compensation is characterized by retrusive maxillary and
protrusive mandibular incisors; and in Class III skeletal
deformity, the compensation is characterized by proclined
maxillary incisors and retroclined mandibular incisors

29. In patients with maxillary transverse deficiency, the
maxillary posteriors are buccally inclined and the
mandibular posteriors may be lingually inclined.
Maxillary transverse deficiency
with excessive curve of Spee and
open bite deformity, which require
segmental Le Fort leveling surgery
to correct
transverse maxillary deficiency and posterior
crossbite. A. Frontal view B. Occlusal view C.
Cephalogram(lateral) D. Cephalogram(PA)

30. ORTHODONTIC PREPARATION
Patients who are candidates for combined orthodontic and surgical correction
must at first have this dentoalveolar compensation eliminated to facilitate the
surgeon to optimally align the jaw bones. The preoperative positioning of teeth
dictates the nature and the extent of the surgical procedure and influences the
final aesthetic results.

31. Poor or lack of presurgical orthodontic preparation with any
residual dental compensation for skeletal discrepancy or failure to
follow the treatment plan will lead to surgical compromise.
Dental relationship before orthodontic treatment
Dental relationship after orthodontic
decompensation. (Exaggerated
reverse overjet visible)
Unilateral cross-biteDental relationship after surgery

32. ORTHODONTIC PREPARATION
In an attempt to achieve a more acceptable and functional aesthetic
result, it may also force the surgeons to perform adjunctive procedures,
such as segmental surgery or genioplasty that was not initially
planned..

33. It is thus important for the surgeons to understand the orthodontic
decision making processes as it is for the orthodontist to have a good
understanding of the presurgical orthodontic requirements. The
orthodontic treatment objectives, extraction patterns and mechanics
used in surgical orthodontic cases differ or may be in opposite to those
used in nonsurgical cases

34. Presurgical orthodontics
The goal of presurgical orthodontics is to decompensate
for dentoalveolar compensation and to position the teeth
upright over the basal bone, while also satisfying spatial
requirements.

35. Presurgical orthodontics
Horizontal plane
In patients with Class II deformity, the objective of presurgical
orthodontics is to procline the maxillary incisors and retract the
proclined mandibular incisors.

36. The decision to extract may be modified by different goals in
the maxillary and mandibular arches. This may result in
extraction of second bicuspid in the upper arch to alleviate
crowding and first bicuspid in the lower arch to align and
retract lower incisors to facilitate mandibular advancement.
Extraction pattern for class II malocclusion
(A) for routin orthodontics ,(B) for surgical
orthodontics .No maxillary extraction is
done,or upper second premolar extraction
is done

37. These extraction choices are opposite to those performed
in conventional orthodontic compensation for Class II
discrepancy where the upper first and lower second
bicuspids are preferred .
. Treatment was started using a splint to stabilize the position of the
mandible, followed by extractions of maxillary first premolars and fixed
appliances to reduce lip protrusion.

38. Skeletal Class II with retrognathic mandible, treated with mandibular
advancement. (A and B) Pretreatment facial photographs. (C and D)
Intraoral photographs.

39. Presurgical decompensation to upright the lower incisors and increase the
overjet. (G and H) Postsurgical intraoral photographs. (I and J) Postsurgical
facial photographs after mandibular advancement.

40. The reverse would be true for skeletal Class III discrepancy where lower
second and upper first, or at times, only upper first premolars would be
extracted to create sufficient negative overjet to facilitate maxillary
advancement and mandibular setback or both .
Horizontal plane
Extraction pattern for class III
malocclusion.(A) for surgical
orthodontics. Extraction of
upper first and lower second
premolar is carried out

41. Case DY. Skeletal Class III with retrusive maxilla, treated with maxillary
advancement. (A and B) Pretreatment facial photographs. (C and D)
Presurgical decompensation to create sufficient reverse overjet.

42. (E and F) Post-treatment intraoral photographs.
(G and H) Post-treatment facial photographs.

43. Vertical plane
A dental compensation in the vertical dimension affects both
maxillary and mandibular incisors; patients with skeletal anterior
open bite pattern have excessive eruption of maxillary and
mandibular incisors, which compensate for the increase in the
lower facial height.

45. Most often, this may result in an
increase in the upper alveolar height
leading to a gummy smile, which may
be aesthetically objectionable.

46. Vertical plane
When the lower facial height is decreased, the curve
of Spee is excessive in the lower anterior with both
infraocclusion of the posteriors and supraeruption
of the anteriors..

47. The presurgical preparation to decompensate
the dentition in the vertical plane depends upon
the anterior facial height

48. Vertical plane
In patients with skeletal open bite, which would require
segmental osteotomy in the maxilla, presurgical
orthodontic preparation should maintain two
different occlusal planes; the anterior segment from
canine to canine and the posterior segment distal to
the canine should be levelled independently by
using a segmental archwire .

49. Case IA with skeletal open bite. (A and B) Pretreatment facial photographs. (C and D)
Intraoral photographs. (E and F) Presurgical decompensation; note the segmental
mechanics for maintaining two independent occlusal planes in the upper arch.

50. note the segmental mechanics for maintaining two independent occlusal planes in the upper
arch. (G and H) Post-treatment intraoral photographs following two-piece maxillary osteotomy. (I
and J) Post-treatment facial photographs.

51. When the lower facial height is reduced as in patients with
skeletal Class II with deep overbite, the dental arches are not
levelled presurgically. The purpose is to maintain the curve of
Spee before surgery, so that the surgical mandibular
advancement will tripod the occlusion on the incisors and
molars. This will result in an increase in the lower anterior
facial height by the virtue of the mandibular incisor teeth
being in an edge-to-edge incisor relationship.

52. The arch can then be levelled postsurgically, primarily by extruding
the buccal segments with intermaxillary elastics in order to level
the curve of Spee, while maintaining the lower facial height .

53. Case MD with decreased lower facial height and skeletal deep bite. Intraoral Class II Div 2 malocclusion
with retroclined incisors treated with mandibular advancement to reduce facial convexity and increase
facial height. (A and B) Pretreatment facial photographs. (C and D) Intraoral photographs. Presurgical
decompensation aimed only at correcting the axial inclination of the incisors. (E and F) Levelling of curve
of Spee is best achieved following surgery.

54. Levelling of curve of Spee is best achieved following surgery. (G and H) Post-
treatment intraoral photographs. (I and J) Post-treatment facial photographs.

55. Transverse considerations
In skeletal Class II malocclusion, the maxillary arch is
constricted; while in Class III malocclusion, the mandibular arch
is tapered. The archforms are corrected presurgically, and then
the arches are coordinated with full-size rectangular archwires
during presurgical orthodontics.

56. In skeletal Class III patients with transverse maxillary
deficiency, either a surgically assisted RPE or a multiple piece
Le Fort I osteotomy can be performed. These two surgical
procedures do not require presurgical arch coordination that
is best accomplished during postsurgical orthodontics.

57. ORTHODONTICS FOR
SURGICAL PATIENTS
Presurgical orthodontics
1. Aligning and levelling by
extrusion
2. Archform coordination
3. Opening space to facilitate
osteotomy cuts
Postsurgical orthodontics
1. Levelling by extrusion
2. Root paralleling
3. Finishing and detailing

58. SURGICAL PROCEDURES
Surgical treatment for dentofacial deformity consists of both
orthognathic procedures to correct jaw relationship and
adjunctive procedures to correct hard and soft tissue contours.
The choice of surgical procedure is dictated by the aesthetic
goals that are determined by the patient’s main concern.

59. Surgical treatment for skeletal Class II malocclusion
Most Class II skeletal malocclusions are corrected by altering the position of the
mandible and chin unlike in the past, where excess overjet was addressed by
performing a maxillary anterior osteotomy by setting the premaxilla back following
premolar extraction..
A, Schematic view of SAMSO showing the undulating
horizontal osteotomy line 3-mm above the canine and
the tooth apices. B, Subperiosteal dissection and
horizontal osteotomy are performed inferior to the
anterior nasal spine
and the piriform aperture.

60. In view of the better understanding of the soft tissue maturity
following ageing and the soft tissue response following
maxillary repositioning, surgery to set the premaxilla is now
avoided. This procedure has the potential to flatten the middle
third of the face and reduce the prominence of the lip, thereby
accelerating the effect of ageing process

61. The mandible can be predictably brought forward to reduce the facial convexity.
The surgical technique of choice is the bilateral sagittal split ramus osteotomy
wherein the distal (tooth bearing) segment of the mandible is brought forward to
obtain maximal intercuspation with the maxillary dentition. The position of the
maxillary and mandibular incisors controls the amount the mandible can be
advanced, as well as the facial aesthetics after surgery.

62. In some patients, the chin may appear deficient after
advancement of the mandible and an advancement
genioplasty may be indicated to improve the final
aesthetics.
A, An osseous genioplasty can be used
to augment the chin, move it posteriorly,
alter its vertical position, or change the
transverse position of the chin. B,
Alloplastic implants can be used to
augment the chin anteriorly. They are
less effective for vertical augmentation.

63. Surgery for Class III skeletal dysplasia
Till the early 1980s, most Class III skeletal pattern was
thought to be due to excessive anteroposterior growth of
the mandible and most were corrected by mandibular
setback procedures.

64. It was later recognized that a majority of
Class III patients have a significant
anteroposterior deficiency of the maxilla.
A and B, A retruded maxilla
undergoing a Le Fort I
osteotomy for advancement.
The traditional Le Fort I
generally angles the osteotomy
from a higher position
anteriorly to a lower point
posteriorly in the zygomatic
buttress area. This creates a
slope along the lateral
maxillary wall. As the maxilla is
advanced forward, it also
moves superiorly along the
bony ramp.

65. Therefore, the clinician must determine whether one jaw is
primarily at fault or a combination of maxillary deficiency
and mandibular excess is causing the malocclusion.
the patient had a Class III skeletal relationship
(ANB angle: −10°) with maxillary retrognathism
maxillary deficiency in combination with relative
mandibular excess.

66. In patients with isolated mandibular excess, bilateral sagittal split
osteotomy and mandibular setback is the procedure of choice,
although a transoral vertical ramus osteotomy may be indicated in
cases requiring larger setbacks.
Photographs of a patient who underwent mandibular
setback: (a) pre-treatment, (b) post-treatment
Photographs of a patient who underwent maxillary
advancement: (a) pre-treatment, (b) post-treatment

67. On rare occasions, procedures, such as body osteotomies or
segmental subapical osteotomies, are indicated. A genioplasty
may at times be necessary for aesthetic positioning of the chin.
Hunsuck's shorter horizontal cut
only extends to the mandibular
foramen in the medial ramus
Rigid fixation of the
segments by lag
screws or plating
GenioplastyAnterior mandibular
subapical osteotomy.

68. The treatment of maxillary anteroposterior deficiency is
accomplished by advancing the maxilla by means of Le Fort I
osteotomy. This versatile procedure enables the surgeon to
correct the discrepancies in the vertical, transverse and occlusal
planes.

69. Most cases of maxillary anteroposterior deficiency also exhibit a
transverse deficiency and the decision has to be made whether a
surgically assisted rapid palatal expansion or multiple piece Le
Fort I osteotomy is to be employed for correcting the transverse
deficiency.

70. Surgery for vertical problems
Maxillary vertical deficiency
Maxillary anteroposterior deficiency is often associated with maxillary vertical
deficiency. It is common in patients with cleft lip and palate because
overclosure of the mandible makes patients with maxillary vertical deficiency
appear clinically similar to those with mandibular anteroposterior excess.
A1-3: Before orthodontic preparation. Retrognathic and narrow maxilla, missing teeth (12,
22, 15 and 25), noticeable alveolar cleft, severe transverse and vertical dislocation of the
smaller segment. B1-3: Orthodontic leveling of teeth in two separate segments. C1-3: Post-op
continuous stainless-steel arch-wires. D1-3: Post-treatment vertical relapse to some extent

71. The clinician must determine whether it is an anteroposterior or a vertical
problem. In patients with maxillary vertical deficiency, the maxilla can be
repositioned inferiorly by a Le Fort I down grafting procedure. This is one of
the least stable of all surgical procedures and rigid fixation must be
employed to improve the stability.

72. Maxillary vertical excess
There is no alternative to surgery for adult
patients with vertical maxillary excess. The
orthodontic preparation and surgical execution
must be very accurate.

73. To correct the vertical excess, the maxilla must be superiorly
repositioned with a Le Fort I osteotomy. The position of the
mandible will be altered following maxillary impaction. If the
overjet continues to be in excess after maxillary impaction, a
sagittal split osteotomy of the mandible must be performed to
reduce the facial convexity.

74. If the overjet is optimal and the facial height continues to be
disproportionate or if there is persistent facial convexity, then a
vertical genioplasty to reduce the vertical height of the chin or
an augmentation genioplasty to improve the facial profile must
be contemplated.
a Le Fort I osteotomy was done with maxilla positioned superiorly by 5 mm and
posteriorly by 4 mm and advancement genioplasty of 5 mm. Postsurgical correction was
maintained by rigid fixation

75. Postsurgical orthodontics
Postsurgical orthodontics can begin 6–8 weeks after surgery or
when the surgeon thinks the healing has reached the point of
satisfactory clinical stability..

76. The first step in postsurgical orthodontics is the removal of the
splint and the stabilization of the archwires, which is followed by
the repairing of the appliance that usually gets damaged during
surgery; following repair of the appliance, light archwire and
elastics are employed to settle the occlusion

77. The elastics, in addition to promoting the settling of occlusion,
override the patients proprioceptive drive towards positioning
the mandible in maximum intercuspation; this will help the
patients in maintaining proper centric relation and occlusion.

78. The vector of elastics depends on the type of surgery. It is
customary to run elastics in Class II vector in patients who
have had mandibular advancements and in Class III vector in
patients who have had maxillary advancement or mandibular
setback or both.

79. Care must be taken to avoid tooth movement that may promote
relapse tendency of the surgical correction, like aligning a
second molar in a patient who has had a surgery to correct a
skeletal open bite.

80. Special consideration must be given for patients who have
had transverse correction, since there is a very strong
relapse tendency for patients who have had transverse
expansion of the maxilla, a rigid overlay archwire (36 mil or
heavier) should be maintained at least for 6 months.

81. Generally, postsurgical orthodontics should not be
performed for more than 3–4 months and an optimum
occlusion must be achieved within this period. Debonding
the appliance and inserting the retainers should follow the
same principles as in conventional orthodontics.
Occlusal splint at the
end of surgery.
Elastics for control.

82. Stability following orthognathic surgery
Current data make it clear that, although modern
orthognathic surgery can move the jaws and dentoalveolar
segments, within limits, in any desired direction, there are
major differences in stability and predictability.

83. Superior repositioning of the maxilla is the most stable
orthognathic procedure
In the surgical phase, a Le Fort I osteotomy was done with
maxilla positioned superiorly by 5 mm and posteriorly by
4 mm and advancement genioplasty of 5 mm.

84. This is closely followed by mandibular advancement in patients with
short or normal face height and less than 10 mm advancement.
Mandibular advancement of 7 mm with
BSSO was
performed, and osteotomy cuts were
secured with titanium plates

85. Both these procedures can be highly stable and exhibit a
more than 90% chance of less than 2 mm change at
landmarks and almost no chance of more than 4 mm
change during the first postsurgical year.

86. Surgical repositioning of the chin via lower border osteotomy,
the most prevalent adjunctive procedure, also is highly stable
and predictable.
A, An osseous genioplasty can be used to augment the chin, move it posteriorly, alter its vertical position, or
change the transverse position of the chin. B, Alloplastic implants can be used to augment the chin anteriorly.

87. Advancement of the maxilla falls into the second category and
can be described as stable. With forward movement of moderate
distances (less than 8 mm), there is an 80% chance of less than 2
mm change, a 20% chance of 2–4 mm relapse and almost no
chance of more than 4 mm change.
The Maxillofacial Surgeon began the surgery performing an osteotomy in the anterior segment (from canine to
canine) of the maxilla; it was advanced 4mm and fixed with monocortical titanium screws and two mini plates.

88. Downward movement of the maxilla is in the problematic
category; if the maxilla is moved both forward and down, the
vertical component is likely to relapse, although the horizontal
component has a good chance of being retained.
Pre- surgical intraoral photograph Post surgical intraoral

89. Correcting maxillary asymmetry usually involves moving
one side up to correct a canted occlusal plane and usually is
done in conjunction with mandibular surgery. The maxillary
component of asymmetry surgery also can be judged to be
stable by the same criteria.
the patient had a transverse asymmetry due to combination
of a rotation of the maxilla (2 mm to the right)
The orthognathic surgery
consisted of 8 mm of maxillary advancement
with a 2 mm rotation to the left and a 2 mm
impaction, combined with 12 mm of mandibular

90. Reference