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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4421_Библиотеки_им_академика_М_И_Перельмана.pdf
Labial side Lingual side
Mandibular Surgical Procedures
8-10 mm
403
26
. Fig. 26.9 The vertical buccal monocortical cut is completed with
the osteotomy carried only halfway through the inferior border of
the mandible. This cut is done with a 703 burr to create enough space
to insert the sagittal splitting instruments
ment and the area to apply a stabilizing bone plate.
For counterclockwise rotation of the mandible, the
buccal horizontal osteotomy can be curved to facilitate better approximation of the segments.
5. The posterior aspect of the horizontal cut is connected to the anterior aspect of the ascending ramus
cut with a #701 ssure bur (. Fig.26.9).
6. A vertical cut is made through the buccal cortex
from the anterior aspect of the horizontal cut,
directed perpendicular to the inferior border of the
mandible using a #703 ssure bur (. Fig. 26.11).
The inferior border is only cut halfway through, not
completely through as in the traditional osteotomy
design.
7. The inferior border osteotomy is performed with
specially designed reciprocating inferior border osteotomy (IBO) saw blade (. Fig.26.12) that are manufactured by two companies: Stryker, Inc.,
Kalamazoo, Michigan and Hall Surgical Division of
Zimmer, Largo, Florida. The osteotomy is initiated
at the anterior vertical buccal cortical osteotomy and
directed posterior to merge on the lingual side at the
posterior aspect of the gonial notch (. Figs.26.13
and 26.14). This inferior border osteotomy signicantly decreases the torque forces required for separation of the proximal and distal segments, reducing
the risk of unfavorable fracture and provides a more
predictable path of lingual fracture to occur decreasing involvement of the IAN (. Fig.26.8) 0.12 With
the split at the inferior border of the mandible, as the
. Fig. 26.10 Cross-sectional view through the distal of the rst
molar. Green arrow shows the horizontal bone cut perpendicular to
the buccal cortex and at a level 8mm below the alveolar bone crest.
Red arrow points to the position of the inferior border osteotomy
mandible is advanced, the lingual cortex remains in
place on the distal segment (.
Fig.26.15, red arrow),
thus eliminating the notching that commonly occurs
with the traditional osteotomy design, particularly
for larger advancements.
8. The proximal and distal segments are completely
separated using the Smith angled separating
instruments and a 3-prong Smith spreader
(W. Lorenz Surgical, Jacksonville, Florida). No
chisels or malleting are generally required in executing the sagittal split osteotomies, thereby minimizing the chances of unfavorable fracture or
inadvertent nerve damage during instrumentation.
In the unusual occurrence of the IAN remaining
adherent to the proximal segment, it is usually
404
ab
L. Wolford
26
a
. Fig. 26.11 The inferior saw blades are designed for the right side and the other for the left side. The saw is designed so that it will cut
halfway across the inferior border of the mandible and has a 5mm vertical stop to prevent injury to the inferior alveolar nerve
b
. Fig. 26.12 a The inferior border osteotomy is initiated anteriorly
adjacent to the vertical buccal osteotomy. The vertical shaft of the
blade is positioned against the lateral cortical plate of the mandible
and this should position the cutting aspect of the blade halfway
related to the cortical bone of the canal incasing
the nerve. The IAN is carefully removed from the
segment sometimes requiring removal of the residual canal bone.
9. If third molars are present, they are removed,
whether impacted or erupted, after the split is complete.
10. The medial side of the proximal segment is
smoothed with a reciprocating bone le, removing
the remnants of the medullary bone and IAN
canal to minimize subsequent injury to the inferior
alveolar nerve when the segments are realigned.
across the inferior border of the mandible. The blade has a vertical
stop and can only penetrate about 5mm into the inferior border. b
Once the saw blade is activated and enters into the bone, it is directed
toward the lingual plate at the posterior aspect of the gonial notch
11. The mandible is mobilized intermediate splint
inserted, and maxillomandibular xation (MMF) is
applied.
12. The anterior aspect of the proximal segment is then
positioned beneath the ledge of the distal segment
(. Fig. 26.15, red circle). This point of fulcrum
allows easy setting of the condyle into the fossa
with gentle pressure applied vertically at the angle
of the mandible (. Fig.26.15, green arrow).
13. Rigid xation is applied. A 6-hole “Z-plate” can be
used (. Fig.26.16a, b), but the surgeon has several
options to provide rigid xation.
Labial side
Mandibular Surgical Procedures
Lingual side
405
. Fig. 26.14 The mandible has been advanced. The red circle
shows the bony interface between the proximal and distal segments
that controls the vertical position of the proximal segment. The red
arrow points to the inferior border cortex that remains attached to
the distal segment, eliminating the inferior border notching that
occurs with the traditional sagittal split techniques. The green arrow
indicates the direction of gentle upward pressure to seat the condyle
into the fossa while rigid xation is being applied
26
.Fig. 26.13 View of the right inferior border of the mandible. Orange
arrow points to the inferior border of the mandible. Blue arrow points
at the angle of the mandible. Green arrow identies the inferior border
saw initiating the osteotomy anteriorly adjacent to the buccal vertical
osteotomy (red arrow). The saw is guided toward the posterior aspect of
the gonial notch and angled toward the lingual plate
a
b
. Fig. 26.15 a Once the segments are properly aligned, a 6-hole
Z-plate can be applied to stabilize the segments as illustrated. If the
bone is extremely thin or for large advancements greater than
10–12mm, then additional supportive screws can be placed bicorti-
cal through the ascending ramus area to provide additional stability.
b Clinical view of the applied 6-hole Z plate. Note the bony interface
between the proximal and distal segments
26
a
406
L. Wolford
14. Surgical areas are thoroughly irrigated with saline
and a nal rinse with betadine solution. The incisions are closed, and MMF and splint are removed.
With this modication, the proximal segment is positionally controlled because of the interface between the
proximal segment and the ledge of the distal segment.
These segments can then be stabilized with a bone plate
or bone screws. In prognathic cases, bone will need to be
removed from the anterior aspect of the proximal segment and along the anterior superior border of the
proximal segment up toward the ascending ramus, for it
to t appropriately beneath the ledge of the distal segment (. Fig.26.17). Whether the mandible is set posteriorly or advanced 5 mm or 20 mm, it can usually be
stabilized with a single bone plate positioned at the
interface of the proximal segment with the ledge of the
distal segment (. Fig. 26.16). For larger mandibular
advancements, or in the presence of thin cortical bone,
1–2 bone screws can be inserted bicortical along the
anterior aspect of the ascending ramus for additional
support.
One advantage of the inferior border osteotomy
modication is that a signicant lower amount of torque
force is necessary to complete the sagittal split compared
to the greater torque force required for the traditional
design. This fact is supported with a recent study by
Bockmann, etal. [12], where they performed an invitro
comparison of sagittal split osteotomy on 35 mandibles
using the traditional Obwegeser/Dal Pont design with 35
sides without and 35 sides with the inferior border osteotomy. The torque used to split the mandibles was measured, and the fracture line position on the medial aspect
of the mandibles was recorded. The average torque for
the original technique without the inferior border osteotomy was 1.38 Newton-meters (Nm) or 1.02-foot
pound force (ft.lbf) with the lingual fracture line along
the mandibular canal, whereas the average torque
required to split the mandible incorporating the inferior
border cut was 1.02Nm or 0.75ft.lbf (P<0.001) with
the fracture line more parallel to the posterior ramus of
the mandible. Bockmann et al. concluded that adding
the inferior border osteotomy to the sagittal split osteotomy resulted in less torque needed to split the mandible and the fracture line was more favorable and
predictable.
26.8.2 Presence or Absence ofThird Molars
Our published study [13] evaluated the outcomes of
mandibular sagittal split osteotomies in two patient
groups relative to the presence or absence of third
molars. Group 1 consisted of 250 sagittal split osteotomies with concomitant removal of impacted third
b
c
. Fig. 26.16 For prognathic cases, this surgical design is very
applicable as well, but does require additional ostectomy procedures.
a–c For mandibular setback, the dotted lines outline areas requiring
bone removal to eliminate bony interferences. For mandibular setback, usually bone removal is required at the vertical buccal osteotomy area of the proximal segment and also along the ascending
ramus. When done appropriately, along with bone removal on the
medial side, allows interdigitation of the two segments
molars at the time of surgery, while Group 2 consisted
of 250 sagittal split osteotomies with the absence of
third molars, using the Wolford modied inferior border
sagittal split technique. The surgical procedure and rigid
xation were performed in the same manner in both
groups. The occurrence of unfavorable splits was 3.2%
in Group 1 and 1.2% in Group 2, but no statistically
signicant difference between the two groups. In
Group 1, unfavorable splits all occurred in teenagers,
with seven of the eight fractures occurring at the poste-
Mandibular Surgical Procedures
407
26
Medial side
Bone removed
Osteotomy
. Fig. 26.17 The medial side of the ramus with the cross-hatched
lines indicating areas on the proximal segment that will require bone
removal of the lingual cortex to allow the segments to sit passively
together
rior aspect of the distal segment through the third molar
socket. This type of fracture is basically a nonissue with
the Wolford method of rigid xation (. Fig. 26.16).
Three fractures occurred in Group 2, all involving fracture of the buccal cortex of the proximal segment, but
the sagittal splits were completed, the fractured buccal
segment restabilized to the posterior part of the proximal segment with the bone plate, and the proximal and
distal segments stabilized in the same manner as the
patients with favorable splits. Outcomes were the same
for all patients relative to stability, whether favorable or
unfavorable splits occurred.
26.8.3 Neurosensory Evaluation ofInferior
Alveolar Nerve
Our study [14] evaluated neurosensory outcomes on the
IAN with sagittal split osteotomies using somatosensory evoked potentials (SEP) computer analysis as well
as conventional two-point discrimination. Forty patients
were evaluated who underwent bilateral mandibular
ramus sagittal split osteotomies using the Wolford modication. All subjects were evaluated postsurgery at 2
weeks, 1 month,6months, and 1 year. At 2 weeks postsurgery, virtually all of the patients had abnormal IAN
SEP recordings whereas at 3 months, 80% of the patients
had complete return of sensation and at 1 year, 100% of
the patients had full return. This study demonstrated
that the Wolford modication performed properly and
carefully, should have low morbidity for long-term decit to the IAN.
Another of our studies [15] involved intraoperative
SEP evaluations of 10 patients undergoing bilateral
sagittal split osteotomies using the Wolford sagittal
split modication. The anesthesia technique was standardized for all patients. SEPs were recorded in surgery to identify where potential IAN injury could
occur during the operative procedure including: (1)
prior to any bone cuts, (2) medial retraction for access
for the medial bone cut, (3) cutting and splitting of the
mandible, and (4) immediately after rigid xation was
applied. The greatest effect on the SEP was the medial
retraction of the inferior alveolar nerve while performing the medial cut on the ramus. There was no signicant noted nerve injury through the rest of the
procedure.
The advantages to the Wolford inferior border oste-
otomy modication include the following:
1. Better bony interface between the segments enhancing healing.
2. Simultaneous removal of impacted or erupted third
molars, if present, without signicant risk of unfavorable split or fracture.
3. Accurate control of condylar position as well as the
proximal segment.
4. No postsurgical MMF required providing better
oral hygiene, speech, and nutrition.
5. The mandible can be advanced a signicantly greater
distance than with the traditional designs.
6. Ease of application of rigid xation intraorally.
7. Temporomandibular joint (TMJ) surgery can be performed concomitantly with the sagittal split osteotomy [16–23].
8. Less risk of damage to the inferior alveolar nerve
[14, 15].
9. Facilitates counterclockwise advancement- rotation
of the maxillomandibular complex [24–27].
The disadvantages of this technique are as follows:
1. Added expense of purchasing the inferior border
saws
2. Learning curve to master the inferior border osteotomy
3. Takes longer surgical time for treating mandibular
prognathism compared to the vertical ramus or
inverted “L” osteotomies
The mandibular ramus sagittal split osteotomy is a
very good procedure for correcting mandibular hypoplasia (retrognathism), mandibular prognathism, and
most asymmetries. The advantages of being able to
correct the jaw alignment, have an excellent bony interface to promote primary bone healing, easy application of rigid xation for stability, have accurate control
of the condylar position, and the benets of no postsurgery IMF make the SSRO a preferred osteotomy
technique compared to others available. The Wolford
408
L. Wolford
26
inferior border osteotomy technique also facilitates
performing predictable redo mandibular sagittal split
osteotomies on patients requiring repeat orthognathic
surgery.
26.9 Vertical Ramus Osteotomy
This technique is rarely indicated in the OSA patient,
but included here for completeness for ramus osteotomies. Extraoral or intraoral approaches can be used for
the vertical ramus osteotomy. This procedure involves
making a vertical cut from the sigmoid notch to the inferior border of the mandibular ramus, posterior to the
lingula. (. Fig.26.18).
The following are indications for vertical ramus oste-
otomy:
1. Mandibular setback.
2. Small movements (unless temporalis, medial
pterygoid, and masseter muscles are detached from
the distal segment).
3. Asymmetries of mandible requiring setback.
4. Mandibular advancements may require coronoidectomies as well as bone grafting between the segments.
Stabilize segments with intraosseous wiring or rigid xation will provide the most predictable results. This procedure is designed to allow the condyle and posterior
border of the mandible to remain essentially in their
original positions (although there is some rotation and
torquing of the condylar head), while the mandibular
ramus and body are moved posteriorly.
Contraindications for the vertical oblique osteotomy
include the following:
1. Large setbacks (unless temporalis, medial pterygoid,
and masseter muscles are detached from the distal
segment).
2. Mandibular advancements,
3. Lengthening of the ramus (unless temporalis, medial
pterygoid, and masseter muscles are detached from
the distal segment).
Advantages of the vertical oblique osteotomy include
the following:
1. Technically easy
2. Correction of mandibular prognathism or asymmetries
Disadvantages of this procedure include the following:
1. Unless segments are wired or rigidly stabilized, it
may be difcult to control the position of the condyle. Condylar sag may result in anterior open bite
postoperatively.
2. Healing time may be increased because of poor bony
interface between segments.
a
. Fig. 26.18 a The vertical ramus osteotomy is illustrated, with the
osteotomy cut extending from the sigmoid notch through the inferior border of the mandible posterior to the lingula. This osteotomy
b
design may be indicated for prognathic cases but rarely indicated for
mandibular advancements. b In mandibular setbacks, the proximal
and distal segments overlap
b
Mandibular Surgical Procedures
409
26
3. Rigid skeletal xation (i.e., bone screws) is difcult
to use through an intraoral approach, so the procedure usually requires 4–8weeks of MMF.
4. Procedure may require relatively long- term interarch
elastics to control occlusion following removal of
maxillomandibular xation because of increased
healing time and lack of condyle positional control.
26.10 Mandibular Ramus Inverted
L-Osteotomy
Extraoral and intraoral approaches to perform the
mandibular ramus inverted L-osteotomy are acceptable
procedures for mandibular setbacks or advancements
(. Fig.26.19). Indications include small or large setbacks, asymmetries, mandibular advancements, ramus
lengthening (. Fig. 26.20), presence of a thin ramus
mediolaterally, and severe decrease in posterior mandibular body height. Contraindications include abnormal posterior location of the mandibular foramina and
mandibular advancements without grafting.
Advantages of the procedure include the following:
1. Correct mandibular prognathism or asymmetries.
2. Coronoid process and temporalis muscle remain in
original position.
3. Mandible can be set back a great distance.
4. Lengthen ramus or advance the mandible when used
with bone or synthetic bone grafting.
5. Rigid skeletal xation can be used.
Disadvantages include the following:
1. Requires bone or synthetic bone grafting for signicant ramus lengthening or mandibular advancement.
2. Healing time may be increased compared with other
techniques because of poor approximation of the
segments when grafts are not used.
26.10.1 Eects onGrowth
Ramus procedures have no signicant affect on the rate
of mandibular growth, providing growth is normal presurgery, but alteration of the position and orientation of
the proximal segment can alter the vector of subsequent
mandibular growth [28, 29].
26.10.2 Age atSurgery
Surgery can be performed predictably from the age of
12years and older as long as normal mandibular growth
is present and there is no preexisting TMJ pathology.
With the sagittal split osteotomy, it is best to use the pro-
a
. Fig. 26.19 The inverted L-osteotomy is a technique that can be
applied to certain OSA patients. A horizontal cut is done superior to
the lingula and the vertical cut is done posterior to the lingula. For
prognathic cases, the distal segment moves posteriorly with the proximal segment overlapping
26
410
L. Wolford
. Fig. 26.20 Illustration of an actual case where the ramus was
lengthened 18mm with an inverted L osteotomy requiring a bone
graft as well as a maxillary osteotomy to downgraft the posterior
aspect also requiring a bone graft. Both areas require rigid xation
for stabilization
cedure after the second molars are erupted so that they
are not injured by the procedure before eruption.
26.11 Complications ofMandibular Ramus
Surgery
ing a Class II open bite. The preferred method of correction for condylar sag is to immediately reposition
the mandibular segments and apply xation to secure
the position of the proximal segment and condyle.
Condylar sag can be avoided by careful surgery, proper
seating of the condyles at surgery, and stabilization of
the segments with screws, plates, and/or wires.
26.11.3 Temporomandibular Joint
Hemarthrosis or Edema
Other possible complications of mandibular ramus surgery are TMJ hemarthrosis and edema. This may displace the condyle downward and forward. Hemarthrosis
and joint edema are caused by traumatic surgery and
uid effusion into the bilaminar tissues or joint spaces.
This can occur with wire or rigid stabilization. For
edema, several minutes of rm upward pressure on the
proximal segment helps to express the majority of the
uid from the bilaminar tissue, allowing the condyle to
seat more appropriately. The application of rigid xation and careful surgical techniques prevent these complications.
26.11.4 Unfavorable Splits or Fractures
Unfavorable splits or fractures most commonly occur at
the buccal cortex of the proximal segment or vertically
through the third molar area of the distal segment.
Management requires careful completion of the split
and stabilization of the segments with bone plates and
screws. When these unfavorable splits occur, proper stabilization of the segments will provide equally stable
results as compared to favorable splits.
26.11.1 Early Relapse
Early relapse usually is related to improper condylar
positioning or slippage between segments during the
healing phase. Relapse is usually signicantly less with
rigid xation compared with nonrigid methods.
26.11.2 Condylar Sag
Condylar sag is a complication of mandibular ramus
surgery, usually caused by improper intraoperative
positioning of the condyle by the surgeon, inadequate
stabilization of the proximal segment, joint edema, or
hemarthrosis such that the condyle is not seated fully
in the fossa. If sag is not corrected, the mandible will
shift posteriorly following the release of MMF, creat-
26.11.5 Extrusion ofTeeth
Extrusion of teeth also may complicate ramus surgery. This is fairly common when interosseous wiring
and maxillomandibular xation are used for stabilization of the mandibular segments. Extrusion also may
occur with postsurgical elastics, particularly when
there is an associated postsurgical malocclusion.
Causes of tooth extrusion include improper skeletal
stabilization, advancement greater than 5mm, short
tooth roots, mobile teeth, condylar sag, and periodontal disease. If extrusion occurs, there is a potential for
orthodontic relapse. Treat extrusion by extensive
orthodontics or reoperate later. Prevent extrusion by
careful orthodontics and surgery and adequate skeletal stabilization.
Mandibular Surgical Procedures
411
26
26.11.6 Periodontal Defects
Periodontal defects are commonly caused by extrusion or
protrusion of teeth, particularly in the lower arch. Poor
hygiene also may contribute to the development of postsurgical periodontal defects. Preexisting periodontal
problems can worsen with orthodontics and surgery.
Improperly performed interdental osteotomies may result
in vascular and periodontal compromise. The difculty of
postsurgical dental hygiene in the presence of numb teeth
and gums may predispose a patient to periodontal disease. Treatment should include frequent professional dental hygiene visits with special attention to home care
regimens. The prevention of periodontal disease should
include appropriate presurgical periodontal management,
good presurgical orthodontics, careful surgery, adequate
skeletal stabilization, and proper oral hygiene techniques.
26.11.7 Temporomandibular Joint
Dysfunction
Preexisting TMJ conditions/pathologies are common in
the OSA patient population and may contribute to postsurgical complications such as TMJ instability, dysfunction, pain, malocclusion, and surgical relapse. These
complications may result from several situations:
5 Preexisting TMJ conditions such as internal
derangement, adolescent internal condylar resorption, reactive arthritis, connective tissue/autoimmune diseases, and other end-stage TMJ disorders
[16–24].
5 Intraoperative or postsurgical joint trauma.
5 Overloading the TMJ related to mandibular
advancement, opening the bite posteriorly at surgery
with splints and then using posterior vertical elastic
mechanics after splint removal to close the bite, and
Class III elastics.
5 Long-term maxillomandibular xation, required
with interosseous wiring (no rigid xation), interferes
with normal nutritional factors and function of the
disc and articular cartilage, resulting in an increased
potential for degenerative changes.
5 Uncontrolled postsurgical muscle dysfunction such
as, trismus, bruxism, and clenching.
5 Preexisting medical conditions such as malnutri-
tion, malabsorption, diabetes, smoking, and immunodeciencies that can interfere with subsequent
healing.
Prevention of postsurgical TMJ complications is based
on proper presurgical evaluation, diagnosis, and management of patients before and after orthognathic surgery [1]. Pretreatment and presurgical evaluation of the
TMJs should include appropriate clinical and imaging
examination. Identify and manage preexisting TMJ disease appropriately. Do not overload the joints by using
excessive forces such as Class III elastics. Patients with a
history of nocturnal clenching and bruxism may require
medications postsurgically to decrease the overloading
effects of these habitual patterns. Mandibular advancements increase the resting pressures within the joints
until the soft tissues have a chance to reequilibrate with
the mandibular alignment. Especially important is to
maintain a closed bite posteriorly with surgery unless
the surgeon is expecting a signicant vertical relapse in
the area. Surgically creating a posterior open bite may
require vertical elastics to close the open bite, which can
overload the joint. Careful surgery minimizing the loading forces on the joint and appropriate management of
the TMJ preoperatively, intraoperatively, and postoperatively minimizes TMJ complications.
26.11.8 Nerve Injury
Several nerve complications also are encountered commonly with mandibular ramus surgery. The inferior
alveolar nerve or its branches may be injured during
ramus, body, subapical, and chin procedures [14–16].
Neuropraxia (type I) nerve injury is not uncommon
with these procedures and is usually temporary. The
cause may be edema, manipulation, stretching, or mild
pinching of the neurovascular bundle. If this problem
occurs, recovery may take from 2 weeks to several
months.
Axonotomesis (type II) injury is caused by a crush-
ing or signicant stretching of the nerve. This can cause
degenerative changes within the distal portion of the
nerve and may take from 3months to 2years to recover,
depending on the severity and location of the injury.
Neurotmesis (type III) nerve injury is a result of sev-
erance or resection of the nerve. Recovery is unpredictable. The best chance for successful recovery is an
immediate direct anastomosis. Delays in surgical management may result in atrophy of the distal portion of
the nerve that will decrease the quality of recovery signicantly.
If the inferior alveolar nerve is severed in a progna-
thic correction, generally the nerve can be repaired
directly without any signicant tension on the nerve.
However, if the nerve is cut during a mandibular
advancement, the appropriate method for management
when performing a primary or secondary repair may
require decortication of the lateral aspect of the mandible overlying the neurovascular bundle up to and including the mental nerve area. The anterior portion of the
inferior alveolar nerve can be cut to allow posterior
repositioning of the distal portion of the inferior alveolar nerve and mental nerve. The repair must be com-
412
L. Wolford
26
pleted with minimal tension. Primary repairs yield the
best results. Secondary repair yields poorer results, especially with long delays (more than 6months). The result
of the repair depends on the type and extent of nerve
injury, the length of time since the injury, the quality
and type of repair, the amount of tension on the repaired
nerve, and the vascularity of the area where the repair is
being performed. If a nerve graft is required, the size,
length, and fascicular pattern affect the results. With a
nerve injury requiring a delayed surgical repair, the complete return of normal sensation is unlikely [14–16].
26.11.9 Infections
Infections usually occur because of breakdown of an
incision with contamination or avascular necrosis.
Indicated treatment includes culture and sensitivity,
appropriate antibiotics, conservative debridement, and
copious and frequent irrigation with saline. The most
common surgical area to become infected is the mandibular sagittal split incision area. If properly managed,
there is little to no consequence. Candida albicans
infections are also common intraorally in some patients.
Systemic antibiotics may increase the incidence of
Candida infection.
26.11.10 Nonunion
Nonunions usually are caused by poor segment alignment, inadequate bony contact or mobility, and inadequate stabilization. Nonunions are best treated early by
providing stability and adequate bony contact between
segments. A long-term nonunion may require reoperation with possible bone or synthetic bone grafting.
Nonunions can be prevented by careful surgery, appropriate immobilization of segments using rigid xation,
and adequate bone contact between segments.
26.11.11 Bleeding Problems
In ramus osteotomies, the most common major vessels
involved in bleeding problems include the inferior alveolar, facial, retromandibular, masseteric, and maxillary
vessels. In mandibular body osteotomies, bleeding
involvement may include the inferior alveolar, lingual,
and facial vessels. Hemorrhage control initially is performed with pressure packing, identication of the
causative vessels, and hemostasis by cauterization,
Avitene (microbrillar collagen hemostat), other hemostatic agents, or ligation. Secondary bleeding is rare but
can be controlled by local tamponade, reexploration of
the wound, or embolization.
In summary, the Oral and Maxillofacial Surgeon
involved in treating OSA patients should understand the
application of the various mandibular osteotomy procedures, posses the skills to execute the procedures when
indicated, and know the potential complications and
how to manage the complication if it occurs. For OSA
patients, mandibular osteotomies to advance the mandible are often combined with maxillary osteotomies for
counterclockwise rotation of the maxillomandibular
complex as well as other adjunctive procedures, such as
partial turbinectomies, septoplasty, uvulopalatopharyngoplasty, and genioplasty, to eliminate airway obstruction, establish a good functional occlusion, eliminate
pain, and enhance facial balance. The goal is to render
the optimal outcome for the OSA patient.
References
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Surgery and Outcome Stability. In Brennan PA, Schliephake H,
Ghali GE, Cascarini L (Editors) Maxillofacial Surgery (3rd
Edition). Elsevier Inc., St. Louis, pp 1048–1126, 2017.
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Kieferhlkd. 1955;23:1–26.
3. Trauner R, Obwegeser H.The surgical correction of mandibular
prognathism and retrognathia with consideration of genioplasty. 1.
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4. Obwegeser HL.Chapter 20; the sagittal splitting of the mandible
procedure. In: Mandibular growth anomalies. Berlin: SpringerVerlag; 2001. p.359–84.
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angled osteotomy design aimed to inuence the lingual fracture
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7. Hunsuck EE. A modied intraoral sagittal splitting technique
for correction of mandibular prognathism. J Oral Surg.
1968;26:250–3.
8. Wolford LM, Bennett MA, Rafferty CG. Modication of the
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