Operative Technique in Plastic Surgery – Kevin C.Chung

TECH FIG 5 • The medial (A) and lateral (B) maxillary
sinus wall osteotomies are demonstrated in a skull
model. C. Completing the medial and lateral maxillary
sinus wall osteotomies by straight osteotomies on the
left side.
■ Maxillary Down-Fracture and Mobilization
■ Down-fracture of the maxilla is achieved with finger pressure placed in the
anterior maxilla and/or with pressure downward on two periosteal elevators
placed in the piriform rim osteotomies bilaterally (TECH FIG 6A,B).
■ If the down-fracture is difficult, then recheck all of the osteotomies to make
sure that they are complete. Roe disimpaction forceps are usually not needed
if the osteotomy is adequate. The forceps may crush the pharyngeal blood
supply and compromise blood flow.
■ After down-fracturing the maxilla, the nasal mucoperiosteum is elevated off
the hard palate in an anterior-to-posterior direction (TECH FIG 6C,D).

■ Ensure that the maxilla is adequately mobilized to provide postoperative
stability.
■ A wooden handle Obwegeser osteotome can be used to further mobilize the
maxilla.
TECH FIG 6 • A,B. Down-fracture of the maxilla
assisted by two osteotomes placed in the piriform
rims. C. The nasal mucoperiosteum is elevated from
the nasal floor from anterior to posterior. D. Location
of the descending palatine neurovascular bundle
(arrow).

■ Removal of Interferences
■ Place a Seldon retractor posterior to the tuberosity on the left side and a
lighted retractor along the anterior nasal floor.
■ Use a periosteal elevator to elevate the mucosa from the nasal floor.
■ Use double action rongeurs to remove the medial sinus wall (TECH FIG
7A). This will facilitate sinus drainage in the postoperative period.
■ A guarded needle tip electrocautery is used to cauterize the descending
palatine artery to reduce postoperative bleeding (TECH FIG 6D).
■ Some surgeons prefer to preserve the palatine artery believing it will
reduce the risk of avascular necrosis of the maxillary.
■ The Seldon retractor is placed posterior to the maxillary tuberosity, and the
steps are repeated on the right side.
■ The nasal floor mucosa is examined for tears; if present, repair them with 4-
0 resorbable suture (TECH FIG 7C).
■ Surgical guide
■ The prefabricated surgical splint is placed in the oral cavity to place the
maxillary teeth into the preset occlusion.
■ The maxilla is wired to the mandible with 26-gauge stainless steel wire
around the surgical hooks.
TECH FIG 7 • A,B. Removing interferences. C.
Closure of any mucosal tears at the nasal floor.
■ Vertical Positioning of the Maxilla
■ The condyles are seated by placing posterior pressure with the thumb on the
chin and upward pressure of the fingers at the gonial notches bilaterally

(TECH FIG 8A).
■ Maxillary bony interferences are removed with a round bur until the maxilla
passively seats in the correct vertical position (TECH FIG 7B).
■ If the vertical placement of the maxilla is determined by measuring the
distance from the K-wire to the orthodontic wire
■ Interferences are then removed as needed to achieve the correct vertical
placement of the maxilla.
■ Proper vertical position is determined esthetically by dental tooth-lip show.
■ The condyles must be appropriately seated during this step to ensure proper
placement of the maxilla and to prevent postoperative malocclusion.
■ If the caudal edge of the septum appears crooked, the free edge of the
septum is dissected from the nasal mucosa and excised. This is also important
if the maxilla requires impaction (TECH FIG 8B–D).
■ The nasal mucosa is then reapproximated with resorbable 4-0 sutures
(TECH FIG 8E,F).

TECH FIG 8 • A. Check for any interferences to be
removed to achieve the desired vertical height. B.
Dissection of the caudal edge of the septum showing
its crookedness. C. Excision of the crooked edge of
the septum. D. The excised part of the septum. E,F.
Closure of dissected nasal septum back to the other
side.
■ Fixation, Occlusal Check, and Closure
■ After the maxilla is properly positioned, it is stabilized with 2.0- or 1.5-mm
titanium miniplates at the piriform rims bilaterally and the zygomatic
buttresses bilaterally (TECH FIG 9A–C).
■ At least two screws on either side of the osteotomy are needed.
■ Large gaps may require greater fixation and/or bone grafts secured at the
lateral wall of the maxilla.
■ Thin bone may require greater fixation along the nasal and zygomatic
buttress.
■ The vertical placement of the maxilla is confirmed with the Boley gauge

after bone grafting and fixation are complete.
■ Maxillomandibular fixation is released by cutting the intermaxillary wires.
■ Occlusion is confirmed.
■ Retractors are used to hold the cheeks out of the way.
■ A thin instrument is used to move the tongue out of the way.
■ The condyles are hinged and passively rotated posteriorly and then
anteriorly.
■ The teeth should contact evenly into the occlusal splint without deviation
or sliding.
■ Wounds are irrigated with normal saline.
■ A wire passing fissure bur is used to make a hole in the ANS (TECH FIG
9D).
■ 2-0 Vicryl is used to suture the nasal septum to the midline (TECH FIG 9E).
■ An alar base cinch is performed with 2-0 Vicryl (TECH FIG 9F–J).
■ The index finger is placed lateral to the ala on one side, and the lip is
retracted upward with the thumb.
■ The suture is passed through the paranasal musculature and through the
hole created in the ANS.
■ The piriform ligament and dilator nasalis muscle are sutured to the ANS in
order to prevent alar dilation.
■ The suture is tightened until the appropriate width of the nasal based is
created and then secured.
■ This maneuver avoids iatrogenic alar base widening that may occur after a
Le Fort I osteotomy advancement.
■ A V-Y closure is performed in the vestibular mucosa with 3-0 chromic gut
(TECH FIG 9K,L).
■ A single skin hook is placed in the midline of the upper lip incision, and
the lip is retracted upward.
■ Two to three interrupted sutures are placed vertically across the incision.
■ This helps prevent lip shortening, lip thinning, and decreased vermilion
show.
■ The vestibular incision is closed by running the 3-0 chromic gut.
■ Guiding elastics are placed at the canines.
■ Gastric contents are suctioned from the stomach with a nasogastric tube.
■ A facial pressure dressing such as a jaw bra with ice packs is placed.

B D Alar base cinch suture F Anterior nasal spine hole

TECH FIG 9 • Fixation is done by two plates in each
side. A. Fixation by two miniplates in the right maxilla.
B. Fixation by two L-shaped miniplates in the right
maxilla. C. Fixation by specially designed prebent T-
shaped miniplate. D. Drilling the anterior nasal spine.
E. Suturing the caudal septum to the anterior nasal
spine. F. Modified alar base cinch suture. G. Suture
bite of paranasal musculature in the right side. H. After
catching paranasal muscles in each side and through
the anterior nasal spine hole. I. Tying the stitch. J. The
effect of alar base cinch suture. K. A single skin hook
is placed in the midline of the upper lip incision, and
the lip is retracted upward to perform V-Y closure
showing during placement of a stitch at the V-Y
junction. L. After complete closure.

PEARLS AND PITFALLS
Preoperative
■ Fully understand the patient’s desires and goals of surgery.
■ Do not rush into surgery. Make sure that patients are orthodontically
set up well for the surgery.
■ Communicate often with the patient’s orthodontist.
■ Patient evaluation and planning are keys to success.
■ Consider VSP for double jaw or asymmetric cases.
■ May need consent for bone graft (which may be taken from the
cranium or the iliac crest).
Approach
■ A short vestibular incision will improve the blood supply to the
maxilla, whereas posterior vertical releasing incisions will allow
increased access.
■ Be sure to place the incision superior enough above the attached
mucosa. This gives a cuff of unattached mucosa to close to at the
end of the case.
Nasal septal
deviation
■ If the maxilla is impacted or simply advanced, it is important to trim
the base nasal septum to prevent buckling or deviation of the nasal
septum.
Osteotomy
and fixation
■ If the maxilla does not easily down-fracture, then retrace the
osteotomies. Do not force the down-fracture.
■ Be sure to seat the condyles completely prior to fixation, or
malocclusion will occur.
■ In thin bone, do not overtighten the screws.
POSTOPERATIVE CARE
■ Intravenous antibiotics are recommended for 23 hours postoperatively.
■ Some surgeons choose to give antibiotics by mouth for an additional 5 to 7
days.
■ Intravenous steroids are given up to three doses.
■ Most patients are extubated postoperatively and placed on a humidified
oxygen face mask and transferred to the post-anesthesia care until recovered.
■ Postrecovery, they are transferred to the floor for overnight observation and
monitoring.
■ Most patients are discharged on postoperative day (POD 1).
■ Diet
■ Clear liquids for 24 hours

■ On POD 1, diet is advanced to full liquids.
■ Puree diet for 2 weeks
■ No-chew, soft diet for 2 to 6 weeks
■ Ice packs, as well as a facial pressure dressing, are used for 24 hours
postoperatively.
■ Head of bed is elevated to 45 degrees.
■ Once home, patients should sleep with two pillows or in a recliner for several
days.
■ Oral care: Patients should brush their teeth at least twice daily starting on POD
1.
■ Sinus precautions/care
■ Open mouth sneezes and no nose blowing
■ Guaifenesin with pseudoephedrine is prescribed for patients who have no
contraindications to decongestants, such as hypertension, for 14 days.
■ Use nasal saline rinses at least twice daily.
■ Elastics training is provided to patient and family. Maintain guiding interarch
elastics for at least 2 weeks.
■ Follow-up is at 1 to 2 weeks, 4 weeks, and 6 weeks.
■ Orthodontic care can resume as early as 4 weeks and usually by 6 weeks.
OUTCOMES
■ Most relapse is within the first 6 months.4
■ Proffit et al. described a hierarchy of stability from most stable to least stable3.
■ Maxilla up (most stable): open bit and nonopen bite
■ Mandible forward
■ Maxilla forward
■ Maxilla up/mandible forward
■ Maxilla forward/mandible back
■ Mandible back
■ Maxilla down
■ Maxilla wider (least stable)
■ Relapse has been reported to be greater than 2 mm in 14% of nonsyndromic
maxillary advancements alone.4
■ Another study showed a similar relapse rate of 20%.5
■ VME patients also had a similar relapse rate.6
■ Horizontal relapse rates are as high as 37% in cleft patients. Relapse is higher

in cleft patients than noncleft patients.7
■ A meta-analysis of MMA revealed 85.5% surgical success rate (AHI less than
20) and a 38.5% cure rate (AHI less than 5) for OSA patients.
■ Surgical cure most likely with preoperative AHI less than 60. AHI greater
than 60 had very low cure rates but did have significant improvements.8
COMPLICATIONS
■ Hemorrhage
■ Damage to the teeth
■ Unfavorable fracture
■ Propagation of fracture to the skull base
■ Propagation of fracture to the septum and cribriform plate
■ Palatal fracture or horizontal fracture of the pterygoid process resulting in
limited maxillary advancement
■ Hardware failure
■ Anosmia
■ Blindness
■ Infection
■ Persistent postoperative pain
■ Neurosensory disturbance (greater and lesser palatine, nasopalatine,
infraorbital nerves)
■ Malunion or fibrous union
■ Vascular compromise and maxillary necrosis
■ Relapse
■ Malocclusion
■ Unfavorable facial aesthetics
■ Pulpal necrosis
■ Lacrimal duct injury
■ Taste alteration
■ Permanent cranial nerve damage
■ TMJ dysfunction
■ Deviated septum
■ Nasal deformity
ACKNOWLEDGMENT

The authors thank Peter D. Waite, MPH, DDS, MD, FACS, for his
contribution to the preparation of this chapter.
REFERENCES
1. Cheung LK, Fung SC, Li T, Samman N. Posterior maxillary anatomy:
implications for LeFort I osteotomy. Int J Oral Maxillofac Surg. 1998;27:346.
2. You-ZH, Bell WH, Finn RA. Location of the nasolacrimal canal in relation to
the high LeFort osteotomy. J Oral Maxillofac Surg. 1992;50:1075-1080.
3. Proffit WR, Turvey TA, Phillips C. Orthognathic surgery: a hierarchy of
stability. Int J Adult Orthodon Orthognath Surg. 1996;11:191.
4. Dowling PA, Espeland L, Sandvik L, et al. LeFort I maxillary advancement:
3-year stability and risk factors for relapse. Am J Orthod Dentofacial Orthop.
2005;128:560-567.
5. Proffit WR, Phillips C, Turvey TA. Stability after surgical-orthodontic
corrective of skeletal class III malocclusion. 3. Combined maxillary and
mandibular procedures. Int J Adult Orthodon Orthognath Surg. 1991;6(4):211-
225.
6. Bishara SE, Chu GW, Jakobsen JR. Stability of the LeFort I one-piece
maxillary osteotomy. Am J Orthod Dentofacial Orthop. 1988;94(3):184-200.
7. Chua HDP, Hägg MB, Cheung LK. Cleft maxillary distraction versus
orthognathic surgery: which one is more stable in 5 years?. Oral Surg Oral
Med Oral Pathol Oral Radiol Endod. 2010;109(6):803-814.
8. Zaghi S, Holty JE, Certal V, et al. Maxillomandibular advancement for
treatment of obstructive sleep apnea: a meta-analysis. JAMA Otolaryngol Head
Neck Surg. 2016;142(1):58-66.

22
CHAPTER
Le Fort I Distraction
Osteogenesis
Nicholas S. Adams and John W. Polley
DEFINITION
■ Maxillary hypoplasia poses both functional and aesthetic challenges.
■ Compromised mastication, speech abnormalities, nasal and pharyngeal
airway constriction, dental malocclusion, and abnormal facial proportions are
common.1
■ Maxillary hypoplasia is a common finding in patients with orofacial clefts.
■ Soft tissue scarring of the palate, pharyngeal structures, and lip may be
severe, creating significant difficulties with traditional maxillary
advancement.1
■ Distraction osteogenesis (DO) is a powerful alternative to traditional Le Fort I
advancement in patients with severe maxillofacial abnormalities. DO allows
for greater advancement (greater than 8 mm) while avoiding the need for rigid
internal fixation or bone grafting.2,3
■ Rigid external distraction (RED) allows rigid, multivector control over the
distraction process, allowing for successful and predictable outcomes.
■ The method outlined in this chapter focuses on Le Fort I DO using the RED
system.2
ANATOMY
■ The maxilla is composed of two adjacent bones that play several roles:
separating the oral and nasal cavities, housing of developing and mature
dentition, supporting the soft tissue of the face, and providing a stable platform
for mastication.
■ In patients with orofacial clefts, the hypoplastic maxilla may be deficient in all
dimensions with thin or structurally weak bone. The mandible is typically

normal in size and morphology.4
■ Severe maxillary hypoplasia can be defined as a negative overjet of 8 mm or
greater.
PATIENT HISTORY AND PHYSICAL FINDINGS
■ Many patients requiring Le Fort I DO have a history of cleft lip and/or cleft
palate.
■ In addition to a complete history and physical examination, complete dental
and orthodontic examination should be done to establish a multidisciplinary
treatment plan.
■ Common physical examination findings in patients with severe maxillary
hypoplasia include a concave facial profile and class 3 relationship with a large
negative overjet, often greater than 8 mm (FIG 1).
■ Scarring of the gingival mucosa may be present if the patient has undergone
correction of orofacial clefts.
FIG 1 • Profile photograph of a patient with severe
maxillary hypoplasia.
IMAGING
■ Preoperative panoramic radiographs are routinely done to assess dental and

osseous anatomy.
■ Cephalograms and photographs are used for preoperative planning and
postoperative comparisons (FIG 2).
■ Computed tomography is not required but may provide further anatomic
details in complex cases.
■ Virtual surgical planning is not necessary for Le Fort I DO.
FIG 2 • Preoperative cephalogram.
SURGICAL MANAGEMENT
■ Criteria for Le Fort I DO include patients with severe maxillary hypoplasia
(horizontal, vertical, and transverse vectors), patients requiring greater than 8
mm of horizontal advancement, severe palatal or pharyngeal scarring, concave
facial profile, and airway obstruction or sleep apnea with normal mandibular
position and morphology.
■ Surgery is delayed until dental and skeletal maturity, if possible, usually
around age 16 to 18 years. Indications for earlier intervention are airway
compromise, severe occlusal disease, or severe psychosocial issues.
Preoperative Planning
■ Preoperative orthodontics are placed to align and level the dental arches prior

to distraction.
■ These movements are planned with dental impressions, casts, and models.
■ If the maxilla and dental arches are severely hypoplastic, preoperative
orthodontics are not used, and the alignment and occlusion are addressed after
distraction is complete.
■ The dental impressions are sent to a dental lab for creation of a custom-made
intraoral splint.
■ The splint acts as the link between the Le Fort I segment and the distraction
device and is applied a few days before the surgical procedure.
■ The splint is then cemented to the first permanent or second primary
maxillary molar (FIG 3).
■ Two large, removable traction hooks made of heavy rectangular wire are
constructed and will be placed when the distraction phase is initiated,
postoperatively.
■ These are not present at the time of surgery to facilitate intraoral
manipulation and airway management.
Positioning
■ Patients are positioned supine with the head supported by a Mayfield headrest.
■ Both arms are padded and tucked at the patient’s side.
■ The bed is placed in a slight reverse Trendelenburg position.
■ Oral intubation is achieved and secured in place with circumdental wiring.
FIG 3 • Intraoral splint design used during maxillary

distraction. Anterior square tubes are used to insert
removable traction hooks. The splint is usually
anchored to the maxillary first molars and secured
anteriorly to maxillomandibular fixation screws placed at
the time of Le Fort I osteotomy.
■ Nasal intubation is not required as mandibulomaxillary fixation and occlusal
analysis are not necessary during the operation.
■ Tarsorrhaphy sutures are placed centrally to protect the cornea, and a throat
pack is placed.
■ A thorough maxillofacial prep including half-strength peroxide oral brushing,
alcohol skin scrub, and betadine paint is completed.
■ Sterile drapes are applied leaving only the face exposed.
■ Exposure of only the nose and mouth is possible as no intraoperative
aesthetic analysis for advancement of the maxilla is necessary.
Approach
■ Access to the maxilla is achieved through an upper buccal sulcus incision.
■ Compared with traditional advancement, the transverse maxillary osteotomy
may be performed much higher allowing for distraction of a larger portion of
the midface.
■ This is possible as preservation of adequate bone stock for internal skeletal
fixation hardware is not necessary.
T E C H N I Q U E S
■ Le Fort I Osteotomy
Soft Tissue Release
■ Local anesthetic with epinephrine is injected at the site of the upper buccal
sulcus incision to minimize bleeding and improve pain control.
■ Maxillomandibular fixation (MMF) screws are placed adjacent to each
maxillary canine tooth root (TECH FIG 1A).
■ A 25-gauge wire is used to attach the preoperatively applied dental splint to

the MMF screws. This provides additional support to the splint during the
distraction phase.
■ The maxilla is approached through an upper buccal sulcus incision extending
between the first maxillary molars bilaterally (TECH FIG 1B).
■ Care is taken to maintain a 3- to 5-mm cuff of buccal mucosa attached to
the gingival mucosal to aid in an eventual watertight closure.
■ A no. 15 scalpel is used to incise through mucosa; dissection is then
continued to bone with needle-tipped electrocautery (TECH FIG 1C).
■ Once through the periosteum, initial elevation of the periosteal dissection
can be done with electrocautery to aid in further subperiosteal elevation.
■ A periosteal elevator is used to release the soft tissue from the maxilla.
■ Dissection is carried out around the pyriform aperture to release the floor
and lateral walls of nasal mucoperiosteum.
■ Superiorly, exposure beyond the level of the planned transverse osteotomy
is performed. Care should be taken to avoid damage to the infraorbital
nerves.
■ Posteriorly, dissection is carried around the maxillary tuberosity toward the
junction of the pterygoid plates for later disjunction.

TECH FIG 1 • A. Intraoperative placement of bilateral
maxillomandibular fixation screws to provide additional
security of the splint to the maxilla. B. Intraoral incision
in the upper buccal sulcus is made through the
mucosa with a no. 15 scalpel. A small cuff of buccal
mucosal is left attached to the gingiva to aid in a
watertight closure. C. Needle-tip electrocautery is
used for dissection through periosteum. Initial
elevation of the periosteum with electrocautery will aid
in further dissection with the periosteal elevator.
Tension and countertension should be applied with the
suction tip.
Bony Release
■ The transverse osteotomy is marked with a sterile pencil.

■ In the mature skeleton, placement should begin at the base of the pyriform
aperture and swing superiorly to include much of the anterior maxillary
sinus wall and as much of the zygoma as desired. Higher osteotomy on the
zygoma will result in a more convex facial profile.
■ The medial portion of the osteotomy is placed low at the pyriform aperture
to prevent excess widening of the nasal base during distraction.
■ Placement should be above the dental roots (TECH FIG 2A). In patients
with mixed dentition, this may be superior to the level of the infraorbital
foramen. In these patients, the osteotomy will circumvent the foramen to
protect the neurovascular bundles and the permanent tooth buds (TECH
FIG 2B).
■ A malleable retractor is placed through the pyriform aperture between the
bone and periosteum to protect the nasal mucosa from damage.
■ The marked transverse osteotomy is made with a reciprocating saw from
lateral to medial (TECH FIG 2C).
■ The posterior portions of the osteotomies are completed with a fine
osteotome along the lateral nasal wall and laterally toward the
pterygomaxillary junction.
■ The plane of the osteotomy should be canted medially and slightly
inferiorly to avoid fracturing into the orbit.
■ The nasal septum is separated with a guarded osteotome to protect the nasal
mucosa (TECH FIG 2D).
■ The index finger is placed in the pharynx to palpate and stop the osteotome
as it is pushed through or struck gently with a mallet (TECH FIG 2E).
■ Pterygomaxillary disjunction is achieved with a curved osteotome placed
just posterior to the maxillary tuberosity against the pterygoid plate.
■ The osteotome is directed slightly inferiorly to avoid the internal maxillary
artery and the pterygoid plexus.
■ The index finger is placed in the hamular notch to palpate the tip of the
osteotome as an assistant carefully strikes the osteotome with a mallet
(TECH FIG 2F).
■ After all osteotomies have been completed, the maxilla is down fractured
(TECH FIG 2G).
■ Complete bony release should be confirmed, but aggressive mobilization is
not necessary, as repositioning is not required.
■ Additionally, bone grafting and fixation hardware are not needed.

■ Once complete release of the maxilla is confirmed, the intraoral incision is
closed with absorbable sutures. A watertight closure should be achieved.

BI E

TECH FIG 2 • A. The transverse osteotomy is marked
with a sterile pencil. This can be placed higher than
with traditional Le Fort I advancement. The maxillary
canine tooth roots are marked to help prevent damage
during the osteotomy. B. The transverse osteotomy
may extend above the level of the infraorbital foramen
to allow for a greater segment of midface to be
advanced. The osteotomy should circumvent the
foramen to prevent damage to the neurovascular
bundle. This also may be necessary to avoid
permanent tooth buds in patients with mixed dentition.
C. A reciprocating saw is used to make the transverse
osteotomy from lateral to medial. A malleable retractor
is placed between the lateral nasal wall and the
mucoperiosteum of the nose to prevent soft tissue
damage. D. The nasal septum osteotomy is
completed with a guarded osteotome. Palpation
behind the soft palate verifies completion while
minimizing trauma to the posterior pharyngeal wall.

E,F. A curved osteotome is placed just posterior to the
maxillary tuberosity, against the pterygoid plates. The
index finger is placed in the hamular notch to palpate
and confirm proper positioning of the osteotome. This
osteotomy should be directed parallel or inferior to the
plane of the alveolar arch to avoid excess bleeding. G.
Down fracturing is done with the aid of a bone hook.
Aggressive mobilization is not required but complete
release should be confirmed.
■ Application of the Rigid External Distraction
Device
■ The halo portion of the RED device (TECH FIG 3A) is placed immediately
after the intraoral incision is closed.
■ Attaching the vertical bar to the halo helps with centering and aligning the
halo during application.
■ The plane of the halo should parallel the Frankfort horizontal plane
(horizontal line through the superior portion of the external auditory canal
and the orbitale) and be placed two fingerbreadths away from the forehead
(TECH FIG 3B).
■ Three scalp pins are used on each side of the halo.
■ These are placed within the hair-bearing scalp and are finger tightened
symmetrically.
■ Finger tightening with the screwdriver completes halo application (TECH
FIG 3C).
■ Ensure the halo is secure by applying force to the metal ring in multiple
directions.

TECH FIG 3 • A. Halo, vertical bar, and adjustment
tools for the RED device. B. The halo portion of the
distraction device is placed parallel to the Frankfort
horizontal plane one to two fingerbreadths away from
the forehead. Use of the vertical bar during application
can aid in alignment. C. The halo is secured with three
scalp pins bilaterally. These are symmetrically
tightened with the screwdriver using fingertip strength
only.
■ Rigid External Distraction

■ 4 to seven days (latency phase) following Le Fort I osteotomy, the remainder
of the distraction device is applied in the office.
■ The two large traction pins are connected to the intraoral splint, so the
hooks are in line with the plane of the palate. These are then connected
bilaterally to the traction screws via wires (TECH FIG 4).
■ Distraction of the maxilla is initiated at a rate of 1 mm/d, usually divided
into two 0.5-mm advancements.
■ The distraction vector is determined by preoperative cephalometric
analysis.
■ The distraction phase typically lasts from 12 to 15 days but the duration
should be dependent on the severity of deficiency.
■ Clinical evaluation of the anterior dental relationship and facial aesthetics
can help guide the extent of distraction.
■ In patients with mature skeletal growth, a class I occlusion is desired.
■ In the growing skeleton, overcorrection of 2 to 3 mm may be desired,
leaving the patient in a moderate class II occlusion.
■ Patients are followed weekly to monitor the distraction process and adjust
the distraction vector as needed.
■ When clinically adequate distraction is achieved (dental occlusion and facial
aesthetics), the RED device is kept in place and on tension during the 3- to 4-
week consolidation phase.

TECH FIG 4 • The patient wearing the RED system.
The intraoral splint is connected to the traction screws
and halo via wires.
■ This allows the maxilla to become clinically stable through bone
mineralization.
■ The halo and dental splint are removed following completion of the
consolidation phase and elastics are placed for 6 to 8 weeks. This is
performed in the office setting.
■ Determination of maxillary consolidation can be made through physical
examination and manual manipulation of the maxilla.
PEARLS AND PITFALLS
Orthodontic
splint
■ In patients with no or inadequate dentition to support the RED
device, plates anchored to the maxilla may be used to apply the
traction force.
Le Fort I
osteotomy
■ Reverse Trendelenburg positioning (15 degrees) and
hypotensive anesthesia can significantly minimize procedural
blood loss.5
■ Use of a malleable retractor between the lateral nasal wall and
the nasal mucosa can prevent damage to the soft tissues of the
nose (see TECH FIG 2C).
■ Incomplete osteotomy will result in failure of distraction. The
RED device will not break unreleased bone.
■ Dissection of the soft tissues from the maxilla can be difficult
on the cleft side in patients with orofacial clefts. Care should be
taken to preserve the soft tissues.
■ Marking of the tooth roots with a sterile pencil prior to
osteotomy can prevent damage to the dentition (see TECH FIG
2B).
■ Contouring and reduction of the nasal vault and anterior nasal
spine in anticipation of advancement prevent widening of the
alar base.
Pterygomaxillary
■ Placement of the osteotome in a superior direction at the

disjunction
pterygomaxillary junction may damage the internal maxillary
artery or pterygoid plexus leading to undesirable hemorrhage.
In the event of significant bleeding, packing should be placed
and hemostasis achieved.
■ Intraoral palpation of the osteotome with the index finger can
help ensure proper placement (see TECH FIG 2E,F).
Rigid external
distractor
■ Symmetrical, finger-tight placement of the scalp pins can
avoid easily preventable complication such as pin loosening. If
the patient has had prior cranial surgery (craniosynostosis),
care should be taken to palpate the cranium for stable bone so
as to avoid pin placement over a portion of the skull that may
be missing bone (see TECH FIG 3C).
Postoperative
■ Continued orthodontic and dental care is required for occlusal
alignment. A final “finishing” Le Fort I osteotomy may be
required in young patients or those with very severe
hypoplasia.2
POSTOPERATIVE CARE
■ Patients are started on a clear liquid diet for 24 hours and then advanced to a
soft diet.
■ Unrestricted diet is allowed throughout the distraction and consolidation
processes.
■ Normal oral hygiene, including gentle tooth brushing, is begun on
postoperative day 1.
■ The head of bed is elevated to help minimize edema.
■ Most patients are discharged from the recovery room or on postoperative day
1.
■ Activity restrictions are in place while the patient wears the RED device to
prevent dislodging or disruption.
■ Patients are counseled preoperatively that they may require a final “finishing”
Le Fort I procedure at skeletal maturity for final arch alignment.
OUTCOMES
■ Several studies have shown long-term stability of the maxilla following Le
Fort I DO.2,6–9
■ When compared with conventional Le Fort I advancement, Le Fort I DO
allows for larger advancements with decreased rates of relapse (FIG 4).
■ This holds true for orofacial cleft patients that frequently present with

significant scarring, greatly restricting maxillary advancement.
COMPLICATIONS
■ The most frequent complications are associated with the scalp pins.
■ Loosening of the pins can occur and should be tightened as needed. This can
be performed in the clinic.
■ Serious complications associated with the halo are rare.13
■ Relapse rates are low and are less than those of traditional orthognathic Le
Fort I surgeries.10–12
■ Dislodging of the halo is possible but uncommon.
■ Patients should be instructed to minimize activities that may jeopardize
device position.
■ Surgical complications including bleeding, dental injury, avascular necrosis,
and surgical site infections are rare.
■ The lack of nonvascularized materials (hardware, bone grafts), along with
minimal dead space associated with Le Fort I DO, reduces the incidence of
infection.
FIG 4 • Preoperative profile photograph (A),

cephalogram (B), and rendering (C) of a patient with
severe maxillary hypoplasia demonstrate a concave
midface, class 3 relationship, and negative overjet.
Postoperative profile photograph (D), cephalogram (E),
and rendering (F) of the patient in FIG 1 show improved
midface projection, facial aesthetics, and dental
occlusion.
ACKNOWLEDGMENTS
The authors thank John A. Girotto, MD, MMA, and Robert J. Mann, MD, for
their contributions to the preparation of this chapter.
REFERENCES
1. Ross RB. Treatment variables affecting facial growth in complete unilateral
cleft lip and palate. Cleft Palate J. 1987;24(1):5-77.
2. Figueroa AA, Polley JW, Friede H, Ko EW. Long-term skeletal stability after
maxillary advancement with distraction osteogenesis using a rigid external
distraction device in cleft maxillary deformities. Plast Reconstr Surg.
2004;114(6):1382-1392.
3. Polley JW, Figueroa AA. Management of severe maxillary deficiency in
childhood and adolescence through distraction osteogenesis with an external,
adjustable, rigid distraction device. J Craniofac Surg. 1997;8(3):181-185.
4. Semb G. A study of facial growth in patients with unilateral cleft lip and
palate treated by the oslo CLP team. Cleft Palate Craniofac J. 1991;28(1):1-
21.
5. Shepherd J. Hypotensive anaesthesia and blood loss in orthognathic surgery.
Evid Based Dent. 2004;5(1):16.
6. Aksu M, Saglam-Aydinatay B, Akcan CA, et al. Skeletal and dental stability
after maxillary distraction with a rigid external device in adult cleft lip and
palate patients. J Oral Maxillofac Surg. 2010;68(2):254-259.
7. Cheung LK, Chua HD, Hagg MB. Cleft maxillary distraction versus
orthognathic surgery: clinical morbidities and surgical relapse. Plast Reconstr
Surg. 2006;118(4):996-1008.
8. Gürsoy S, Hukki J, Hurmerinta K. Five-year follow-up of maxillary
distraction osteogenesis on the dentofacial structures of children with cleft lip
and palate. J Oral Maxillofac Surg. 2010;68(4):

744-750.
9. Kanno T, Mitsugi M, Hosoe M, et al. Long-term skeletal stability after
maxillary advancement with distraction osteogenesis in nongrowing patients. J
Oral Maxillofac Surg. 2008;66(9):1833-1846.
10. Baek SH, Lee JK, Lee JH, et al. Comparison of treatment outcome and
stability between distraction osteogenesis and LeFort I osteotomy in cleft
patients with maxillary hypoplasia. J Craniofac Surg. 2007;18(5):1209-1215.
11. Chua HDP, Cheung LK. Soft tissue changes from maxillary distraction
osteogenesis versus orthognathic surgery in patients with cleft lip and palate—
a randomized controlled clinical trial. J Oral Maxillofac Surg.
2012;70(7):1648-1658.
12. Chua HDP, Hägg MB, Cheung LK. Cleft maxillary distraction versus
orthognathic surgery—which one is more stable in 5 years? Oral Surg Oral
Med Oral Pathol Oral Radiol Endod. 2010;109(6):
803-814.
13. Aizenbud D, Rachmiel A, Emodi O. Minimizing pin complications when
using the rigid external distraction (RED) system for midface distraction. Oral
Surg Oral Med Oral Pathol Oral Radiol Endod. 2008;105(2):149-154.

23
CHAPTER
Segmental Le Fort I
Advancement: Two and
Three Piece
Leo J. Urbinelli and Jeffrey A. Hammoudeh
DEFINITION
■ Le Fort I osteotomies (single or multipieced) are performed to reposition the
teeth-bearing segment(s) of the maxilla and to surgically correct skeletal
malocclusion, dentofacial asymmetries, and midfacial deficiencies or excess.
■ Segmentation as a multipiece Le Fort I osteotomy is frequently used to
modify the transverse dimension of the maxilla to provide a more optimal
occlusion between the maxillary and mandibular teeth.
■ Segmentation is more commonly performed when the presurgical
orthodontia is suboptimally leveled, aligned, and coordinated, which is more
common in the cleft palate patient.
■ Skeletal malocclusion is best defined by Dr. Edward Angle’s classification
(FIG 1) to assess dentofacial deformities that may require orthognathic surgery
or in particular a Le Fort I maxillary advancement.
■ Class I occlusion is present when the normal relationship of the maxillary to
mandibular teeth exists: the mesiobuccal cusp of the maxillary first molar
intercuspates within the buccal groove of the mandibular first molar.
■ In class II malocclusion, the mesiobuccal cusp of the maxillary first molar
sits too far anterior and does not seat into the mandibular buccal groove of the
first molar, as in the case of mandibular retrognathia.
■ In class III malocclusion, the mesiobuccal cusp of the maxillary first molar
lies posterior to the mandibular first molar’s buccal groove as is seen in
mandibular prognathism.
■ Le Fort I advancement surgery requires the surgeon to understand facial
aesthetics, dentofacial relationships, and cephalometric norms in order to

accomplish a suitable and stable surgical outcome.
FIG 1 • Angle classification of occlusion.
■ Cephalometric norms have traditionally been regarded standard in the workup
of orthognathic cases and are important from an educational, academic, and
historical standpoint.
■ However, the limitations of cephalometric two-dimensional analysis have led
to three-dimensional (3D) computed tomography scanning for virtual surgical
planning (VSP).
■ 3D VSP is our recommendation for complex orthognathic surgery.
■ Two-piece segmental Le Fort I maxillary advancement surgery is indicated
when maxillary advancement alone does not correct the transverse discrepancy.
■ In the noncleft patient, the traditional segmentation of the maxilla is between
the two maxillary incisors in a midsagittal osteotomy from the anterior nasal
to the posterior nasal spine.
■ In the cleft patient who has undergone alveolar cleft repair, it is reasonable to
consider the segmentation at the alveolar cleft site to mitigate vascular
compromise of the segments.
■ Three-piece segmental Le Fort I maxillary advancement surgery is often
indicated in the cleft lip and palate and/or syndromic craniofacial patient, when
it is determined from physical exam that the patient has midfacial hypoplasia in
the anteroposterior dimension and/or class III malocclusion in the setting of an
arch that has suboptimal leveling, aligning, and coordination.
■ This is exemplified by physical examination, dental model analysis,

cephalometric evidence, an acute sella to nasion to A-point angle (SNA angle
less than 79 degrees), and VSP analysis (FIG 2).
ANATOMY
■ Le Fort I osteotomy is defined by sectioning of the bony maxilla above the
apices of the teeth but below the level of the nasal bones, through the nasal
septum, and completing the disjunction at the pterygomaxillary junction.
■ Segmentation of the Le Fort I maxillary segment is done by sectioning the
maxilla between the tooth roots to allow expansion or reduction in the
transverse plane, often completed after down-fracture of the tooth-bearing
maxillary segment.
■ Segmentation for a two-piece Le Fort is routinely between the maxillary
central incisors in a midsagittal osteotomy (FIG 3).
FIG 2 • Virtual surgical plan of three-piece Le Fort I
osteotomy.
■ In the cleft patient who has undergone alveolar cleft repair, if the alveolar
cleft repair bone quality/take is less than optimal, it is reasonable to cut at the
alveolar cleft site and extend the segmentation to the midsagittal osteotomy.
■ This technique minimizes the potential vascular risks to the anterior

maxillary segment.
■ Blood supply to the maxilla is rich and redundant in the noncleft patient.
■ After sectioning of the Le Fort I osteotomy, the blood supply depends on
branches of ascending pharyngeal and ascending palatine arteries.
■ The descending palatine arteries can often be seen upon down-fracture and
may be ligated if bleeding, as they will not compromise the vascularity of the
maxilla if these are divided (FIG 4).1
■ Blood supply to the maxilla in the cleft lip/palate and syndromic craniofacial
patient is less abundant and predictable due to potential previous surgical
interventions, but maxillary segmentation can be done safely when risk
mitigation techniques are used.
FIG 3 • A. Two-piece Le Fort I segmentation planned
using the stone model. B. Intraoperative view after Le
Fort I osteotomy, down-fracture, and two-piece
segmentation.

FIG 4 • Palatine arteries after down-fracture in Le Fort I
osteotomy.
■ These techniques include using a high-cuffed gingival incision, minimizing
the dissection to what is needed, minimizing the segmentation to a two-piece
maxilla if feasible, and keeping the total maxillary advancement to less than
10 mm.
■ Potential maxillary vascular compromise in a cleft lip/palate patient
undergoing a three-piece Le Fort I osteotomy must be discussed with the
family and patient preoperatively as this multisegmentation may predispose to
a loss of teeth, bone, or even the entire premaxillary segment.
■ These risks cannot be eliminated, but they can be mitigated using the
techniques described above. A three-piece Le Fort segmentation can be
performed reliably with stable and predictable results by experienced
clinicians.
PATHOGENESIS
■ Developmental skeletal dysplasia, in particular midfacial hypoplasia and
dental class III malocclusion, is a multifactorial skeletal deformity of the face.
■ Factors contributing to this deformity are genetic, environmental, idiopathic
and potentially iatrogenic.

■ This deformity can be found in cleft, noncleft/nonsyndromic, and syndromic
craniofacial patients.
■ Cleft palate repair and healing have been associated with a higher incidence of
midfacial hypoplasia, transverse maxillary discrepancy, and overall
malformation of the facial skeleton and dental malocclusion.
■ Midfacial hypoplasia requiring a Le Fort I advancement is seen in up to 25%
of complete cleft lip and palate patients.2
NATURAL HISTORY
■ Children with orofacial clefts may or may not have normal occlusal
relationships in early development; however, as they skeletally develop,
maxillary growth often lags behind mandibular growth giving a concave
midfacial appearance and class III malocclusion.
■ With small disturbances in occlusion, orthodontics and headgear can be used
to distract the maxilla in reference to the mandible.
■ However, the natural history of many orofacial cleft patients is that a larger
midfacial discrepancy (4–15 mm) of a negative overjet exists, requiring
surgical intervention to advance the maxilla in relation to the lower jaw as
well as surgically correct transverse discrepancies.
■ With anterior maxillary advancement of less than 10 mm, the prognosis for
low relapse rates and long-standing, stable results can be accomplished with a
segmented Le Fort I advancement.
■ Maxillary transverse expansion is associated with a higher risk of relapse in
both noncleft and cleft patients.
■ The cleft patient transverse relapse risk is higher and is correlated with the
history of previous palatal operations, fistula repairs,
pharyngoplasty/pharyngeal flaps, sequences/syndromes, and operative
technique (fixation technique as well as the overall movement metrics).
■ We recommend minimizing the segmentation, using rigid fixation and
postoperative splint retention with a palatal bar. In some circumstances where
fixation is suboptimal, a period of closed reduction is indicated.
PATIENT HISTORY AND PHYSICAL FINDINGS
■ History should include inquiry into the past medical and dental history,
documenting the extent and progress of presurgical orthodontia.
■ The clinician should note any pain on jaw opening and closing or difficulty
eating, speaking, or closing the mouth without strain of the chin. One should

also elicit history of prior airway comorbidities, sleep disturbances
(obstructive sleep apnea, enlarged turbinates), or prior surgery (palatal, speech
or velopharyngeal surgery, prior jaw or nasal surgery).
■ Additionally, one should ascertain if the patient has completed skeletal growth
(continued height, foot, and hand growth), as Le Fort I advancement surgery is
most stable and indicated when skeletal maturity is reached.
■ History of orthodontic treatment (duration, modalities) should be assessed.
■ Physical examination should include an overall assessment of facial balance
and proportions including photo documentation of the frontal, lateral, and
oblique face in the repose and in full animation; this should include a focused
intraoral exam.
■ This intraoral exam is imperative to assess overall dental health,
missing/diseased teeth, previous palatal surgery, or scarring over the
buccal/gingival mucosa.
■ Intraoral pictures should be obtained of midline occlusal as well as bilateral
canine to mandibular molar relationships.
■ Intraoral exam should include inspection of orthodontia (wires, brackets,
hooks, etc.) and clearly identify the dental malocclusion, skeletal dysplasia,
and if any maxillomandibular cant exists.
■ Bimanual palpation of the temporomandibular joint on opening and closing
of jaws for preoperative assessment of this complex joint is crucial.
■ Palatal and oronasal fistulae should be noted. The pharynx should be
examined as well as a detailed intranasal exam performed to check for any
septal deviation, perforations, or enlarged turbinates.
■ One of the most effective orthognathic surgical options in addressing midfacial
hypoplasia with class III malocclusion is to combine a Le Fort III osteotomy in
conjunction with a multiple-piece Le Fort I osteotomy.
■ This can make a profound change and correct a midface global hypoplasia in
conjunction with severe dental malocclusion (FIG 5).
IMAGING AND OTHER DIAGNOSTIC STUDIES
■ Traditionally, posteroanterior and lateral cephalograms as well as a panoramic
x-ray are obtained (FIG 6).

FIG 5 • Virtual surgical plan of combined Le Fort III
osteotomy and advancement with three-piece Le Fort I
segmentation.
FIG 6 • Panorex (A) and posteroanterior (B) and lateral

(C) cephalograms.
■ Periapical views around missing bone along the alveolus may allow the
surgeon to assess if simultaneous bone grafting is needed at time of Le Fort I
advancement.
■ Craniofacial CT scanning has become the mainstay in complex orthognathic
surgery and is a requirement for 3D VSP, model, and splint fabrication.
■ To facilitate the VSP, the preoperative occlusion must be obtained via dental
stone models with bite registrations, or a digital dental scan of the teeth can be
performed, which is then incorporated into the craniofacial CT for the VSP.
■ 3D tissue rendering can also be used by overlapping the soft tissue window
on top of the bony images.
■ Traditional imaging, plaster model surgery, and splint fabrication still remain
an acceptable preoperative workup for orthognathic surgery.
■ Preoperative splint fabrication is key to achieving an intraoperative result,
which matches the preoperative plan. Segmental Le Fort splints should have a
palatal bar incorporated to provide additional stabilization and minimize
relapse; this is particularly important in the cleft palate patient.
SURGICAL MANAGEMENT
Preoperative Planning
■ Stress importance of education with family and patient on pre- and
postoperative nutritional optimization, oral hygiene, postoperative activity
restrictions, and the likelihood of having a splint in place postoperatively.
■ In the cleft patient, discussion on the potential of remaining in
maxillomandibular fixation (MMF) for a postoperative period of several weeks
should be conducted.
■ Duration of MMF is clinician dependent and is related to the extent and
direction of movement in the maxilla, the previous surgical history, and the
stability of the rigid fixation.
■ The possibility of postsurgical MMF can be anxiety provoking for patients
and made easier by thorough preoperative discussion and education.
Positioning
■ Patient is placed supine on the operating room table with a padded shoulder
roll placed to maintain the head and neck in a neutral or slightly extended

position.
■ Intubation is often preferred via an endonasal-tracheal route to avoid difficulty
in assessing occlusion during the procedure.
■ Care must be taken to ensure the tube’s security, and this is achieved by
securing the endotracheal tube to the caudal nasal septum using a 2-0 silk
suture in a horizontal mattress fashion with care to avoid the endotracheal
tube from placing pressure on the nasal ala.
■ The tube is draped cranially up over the forehead, padded, and secured with
another circumferential 2-0 silk suture anchored to the scalp within the
anterior hairline (again to avoid pressure of the tube on the alar rim of the
nose or skin of the face; FIG 7).
■ If the vertical position of the maxilla is going to be altered, it is helpful to use a
reference marker.
■ This is made either via Kirschner wire anchored at the nasofrontal junction or
via tattoo at the medial canthus using 25-gauge hollow-bore needle and inked
dye (methylene blue or gentian violet).
FIG 7 • Frontal (A) and lateral (B) views of
intraoperative draping showing endonasal-endotracheal
tube position, padding, sterile draping, and positioning.
■ This reference mark will be used to measure preoperative measurements to
the right and left occlusal surfaces of the maxillary teeth (or orthodontic

brackets) and ensure the postoperative vertical position of the maxilla is
achieved as planned.
■ Two large-bore IVs are placed at the start of the case for fluid resuscitation
management.
■ An arterial line and a Foley urinary catheter are typically placed. The arterial
line will allow the surgeon and the anesthesiologist to assess the hypotensive
anesthesia (mean arterial pressure less than 60) that is typically required during
the maxillary down-fracture.
■ A dose of IV dexamethasone is given in the OR as well for edema
management. An IV dose of antibiotics (clindamycin or ampicillin) is given for
prophylaxis.
■ Intraoral chlorhexidine solution is used to wash the face and eyelids closed
with occlusive dressings to avoid corneal abrasions. The face is prepped with
dilute Betadine.
Approach
■ Intraoral approach is standard with infiltration of local anesthesia (0.25%
bupivacaine with 1:200 000 epinephrine solution) along the gingivobuccal
sulcus of the maxilla as well as intranasally into the nasal septal mucosa.
T E C H N I Q U E S
■ Incision and Dissection
■ With the upper lip retracted atraumatically, an upper gingival incision is
made leaving a generous (5–7 mm) cuff of gingiva in place to facilitate easy
watertight closure.
■ This incision is extended from first molar to first molar with needle tip
electrocautery on a low setting. Incise perpendicular to the mucosa and then
aim perpendicular to the bony maxilla to avoid perforations of the nasal
mucosa and injury to the facial muscles or buccal fat. This also helps avoid…
avoid “buttonhole” perforations in the gingiva.
■ Once the periosteum is palpated and noted, it is scored with the
electrocautery from the lateral maxillary buttress to below the level of the
piriform apertures bilaterally.

■ Using a sharpened periosteal elevator (Molt no. 9 or equivalent), a
subperiosteal dissection is performed bilaterally over the face of the maxilla,
extending medially along the medial buttresses, superiorly to the level of the
infraorbital nerves, and laterally around alveolar processes of the maxilla to
the pterygomaxillary junction.
■ Care is taken around the piriform apertures bilaterally to avoid perforation
into the nasal mucosa; often, this dissection is performed with a Freer
elevator to free the floor of the nose and caudal septum from the cranial
surface of the palate.
■ Le Fort I Osteotomy of the Maxilla
■ Once exposure is obtained, marking of the planned osteotomy with a sterile
bone pencil or electrocautery scoring is performed to indicate the level
medially and laterally of the height of the osteotomy that should be made.
■ Intranasally, this is never higher than the inferior turbinates and always
above the level of the apices of the teeth (maxillary canine is the longest—
up to 30 mm).
■ Prior to sectioning the bone of the maxilla, hypotensive anesthesia is
preferred with mean arterial pressures in the 45 to 59 mm Hg range to assist
with visualization and mitigate blood loss from bony edges.
■ The osteotomy is performed with either a reciprocating saw or an ultrasonic
bone saw, cutting first from the medial (piriform rim) to lateral buttress or
from lateral to medial along the anterior maxilla while placing a malleable
Freer elevator to protect the nasal lining and endotracheal tube from saw
injury.
■ The same osteotomy is completed on both sides of the maxilla (TECH FIG
1).
■ A curved blunt-ended “pitchfork” osteotome is then used to straddle the
caudal septum with the nasal mucosa elevated in a protected manner, and a
mallet or digital pressure is used to divide the vomer from the bony palate.

TECH FIG 1 • Le Fort I osteotomy.
■ Often, a hand is placed intraorally along the soft palate to palpate when the
osteotomy is complete and stop unwanted injury to the soft palatal tissues and
associated local structures.
■ After separation of the septum from anterior to posterior nasal spine, the
osteotomy of the lateral wall of the maxillary buttress is completed with a
thin ribbon osteotome.
■ The posterior wall of the maxilla is gently sectioned using either an
osteotome and a mallet or an ultrasonic saw.
■ The bone in this region is thin, and care should be taken to avoid injury to
the descending palatine artery, internal maxillary artery, and the pterygoid
plexus.
■ Using a curved narrow osteotome and mallet, the lateral and posterior most
extent of the Le Fort I osteotomy is completed with a hand placed intraorally
and finger placed in the retromolar area over the hamulus to palpate the
medial extent of the osteotomy, serving as a guide to the separation and to
minimize injury to the intraoral mucosa and local structures.
■ The curved osteotome should be placed posterior to the maxillary
tuberosity within the pterygomaxillary groove, angling transversely and
slightly caudal.
■ Prior to down-fracturing the maxilla, the clinician should identify the region
for segmentation, and the corticotomy should be made meticulously under
direct vision making sure not to injure the roots of the teeth.

■ Down-Fracture of the Maxilla
■ When the lateral pterygoid plates are sectioned from the maxilla, the tooth-
bearing maxilla will be separated from the cranial portion with gentle digital
downward pressure.
■ Bone spreader (laminar spreader) can be used at the thick medial and lateral
maxillary buttresses to be sure maxillary down-fracture is complete.
■ If down-fracture does not occur with digital pressure, take time to recheck all
previous osteotomies for completion as the down-fracture should be
controlled, along previous osteotomy lines in order to avoid unfavorable
fractures.
■ With maxilla down-fractured and soft tissues stretched, one should evaluate
and control any bleeding with bipolar cautery and/or packing and evaluate for
any tears in nasal mucosa, which should be repaired with absorbable suture to
avoid synechiae or nasal bleeding postoperatively.
■ With down-fracture completed, Rowe disimpaction forceps and/or pterygoid
S-shaped retractors can be placed bilaterally in the piriform or behind the
lateral pterygomaxillary osteotomies, respectively, to stretch and advance the
maxilla in an anterior plane, taking care to do this in a controlled fashion on
slow stretch to avoid avulsion of soft tissue and hence blood supply.
■ Segmentation of the Maxilla
■ Controlled segmentation of the maxilla (into two or three pieces) is often
performed in patients with unilateral/bilateral cleft palate and alveolus, in
syndromic patients with skeletal dysplasia, and in otherwise healthy patients
who have suboptimal orthodontia.
■ Converting the segmentation corticotomies, made prior to down-fracture of
the maxilla, to segmented osteotomies is now undertaken (Video 1).

Video p2-c023
■ In the cleft palate patient requiring a two-piece segment, it is often preferred
to go through the alveolar cleft anteriorly where the bone stock is lower in
general.
■ This also helps mitigate vascular compromise.
■ The alveolar osteotomy is generally between the canine and premolars
(sometimes between canine and lateral incisors), and then is extended
posteromedially to meet a midsagittal osteotomy.
■ In the cleft palate patient requiring significant transverse expansion and
multiplane occlusal correction, three-piece segmentation is ideal.
■ Again, the alveolar segmentation is usually at the canine-premolar (or
sometimes canine-lateral incisor) regions bilaterally, and then the
osteotomy is extended posterior medially to parasagittal osteotomies in a
“horseshoe” fashion.
■ The parallel parasagittal osteotomies provide the advantage of increased
transverse expansion and minimized soft tissue trauma to the midpalatal
region, which is generally more tenuous (TECH FIG 2).
■ In a noncleft patient requiring a two-piece segmentation, this is traditionally
achieved by planning a standard Le Fort I osteotomy in conjunction with
segmentation between the two central incisors.
00:00 / 00:00

TECH FIG 2 • Three-piece segmentation of the maxilla
along parasagittal markings.
■ This can be accomplished by performing the traditional Le Fort I, and then
prior to down-fracturing, a corticotomy is made from the anterior nasal
spine caudally under direct vision between the central incisors.
■ This can be done initially with the reciprocating saw or ultrasonic
handpiece. The corticotomy then is made from the anterior nasal spine
posterior with a small thin osteotome.
■ Subsequently, the down-fracture is completed, and then the segmentation
osteotomy can be propagated and completed after the down-fracture under
direct vision.
■ This stepwise method allows for a more controlled down-fracture of the
maxilla and a directly visualized segmentation.
■ For the noncleft patient requiring a three-piece Le Fort I osteotomy, the
traditional Le Fort I osteotomy is made, and in similar multisegmentation
sequence, the segmentation corticotomies are made prior to down-fracture;
then, after down-fracturing, the segmentation osteotomy can be completed.
■ The segmentation is traditionally between the canine and premolar teeth
bilaterally and then extends posterior medially into the midpalatal area,
which then gets propagated posteriorly to the posterior nasal spine
(“Mercedes” configuration).
■ Some clinicians prefer bilateral parasagittal osteotomies and a “horseshoe”
configuration as this allows for increased transverse expansion and avoids
potential midpalatal soft tissue injuries.

■ Ultimately, osteotomy segmentation location, type, and configuration
depend upon best fit occlusion, extent of transverse expansion, and cant
correction as determined in preoperative model planning as well as clinical
judgment.
■ The osteotomies are made with a reciprocating saw, an osteotome and a
mallet, and/or an ultrasonic saw from posterior to anterior and cranial to
caudal directions.
■ Digital palpation along the palatal mucosa is used to detect when the saw
has completed the bony cuts and to avoid injury to the palatal mucosa.
■ Once the osteotomies are made, they are completed through the alveolar
ridge and between the teeth carefully using fine osteotomes and mallets.
■ The attached gingiva is elevated atraumatically and remains intact over this
interdental alveolar bone, which is segmented to maintain a rich blood
supply to the segmented tooth-bearing maxillary segments.
■ The osteotomies are propagated with a T-handle osteotome using small
rotary movements to ensure the soft tissue can be stretched and the maxilla is
spreading to show completion of osteotomies.
■ Final maxillary splint is placed and wired to the teeth/orthodontia to ensure
transverse expansion/reduction has been obtained.
■ If a segmental Le Fort I is performed to reduce the height or transverse width
of the maxilla, this can be done with soft tissue dissected using a Freer
elevator to maintain periosteal blood flow to the maxilla.
■ The caudal nasal septum may need reduction to avoid bowing or septal
deviation postoperatively for a planned maxillary impaction.
■ Transverse Expansion and Advancement of the
Maxilla
■ After down-fracturing of the maxilla and completion of the
multisegmentation into two or three pieces (by propagating the segmentation
corticotomies with an osteotome), the maxilla is seated into the splint with
26-gauge wires.
■ The maxillomandibular unit is secured together with a 24-gauge wire by
mobilizing the maxilla/splint into occlusion with the mandible.
■ The maxillomandibular unit is rotated into its final position with bone-to-
bone contact.

■ This rotation should be accomplished passively to ensure that the
mandibular condyles remain seated in the glenoid fossa.
■ The position should be evaluated in relation either to internal reference
markers or to external reference points (K-wire or tattoo) to ensure the
planned postoperative movement is achieved; this is particularly important
when there is a significant cant correction.
■ Fixation of the Maxillary Segments
■ With the maxilla in proper position and seated appropriately in MMF with
the occlusal surfaces fitting exactly into the splint, the maxillomandibular
unit is passively rotated into the new position with stable bony contact.
■ The maxillary segments are then fixated to each other and to the cranial
aspect of the maxilla along the medial and lateral buttresses using 2-mm-
thick L-shaped plates along the lateral buttresses and 2-mm-thick inverted-
T–shaped (Lindorf style) plates along the medial buttresses to capture the
central and lateral segments in three-piece maxillary movements.
■ Nonlocking plates and screws are acceptable, and these should be placed
above the level of the dental roots.
■ The plates are bent to follow the natural contours of the maxilla and newly
advanced maxilla (TECH FIG 3).
TECH FIG 3 • A. Three-piece Le Fort I osteotomies
fixated with Lindorf plates and screws. B. Completed
three-piece Le Fort I osteotomies, fixation with Lindorf
plates along medial buttresses, and L-shaped plates
at lateral buttresses. Newly established occlusion is