Operative Technique in Plastic Surgery – Kevin C.Chung

18
CHAPTER
Orbital Expansion for
Anophthalmia and
Microphthalmia
Brad Morrow and Rogerio I. Neves
DEFINITION
■ Anophthalmia, either congenital or acquired, is a rare condition in the pediatric
population.
■ Development of the globe is critical for the stimulation of orbital and
maxillofacial growth.
■ Absence of a globe results in severe facial asymmetry due to bony and soft
tissue hypoplasia.1,2
■ Anophthalmia presents a unique challenge to the reconstructive surgeon to
create an aesthetic orbit, restore facial harmony, and improve the psychosocial
well-being of the affected child.
■ Orbital expansion is a minimally invasive technique that avoids the morbidity
of orbital osteotomies. In properly selected patients, accelerated orbital growth
is achievable and can reverse the midface discrepancies by bone remodeling.
ANATOMY
■ Although the orbit is a pear-shaped cavity with a posteriorly tapering apex to
the optic canal, it can be thought of as a box with four walls: medial, lateral,
floor, and roof (FIG 1A).
■ The medial wall, composed of the ethmoid, lacrimal, maxillary, and sphenoid
bones, is the thinnest section and adjacent to the ethmoid and sphenoid
sinuses.
■ The lateral wall, composed of the zygoma and the greater wing of the
sphenoid, is the thickest section and extends to the equator of the globe to
protect the posterior portion, yet allow for peripheral vision. It is separated

from the lesser wing of the roof by the superior orbital fissure (FIG 1B,C).
■ The floor, composed of the maxillary, palatine, and zygomatic bones, ends at
the pterygopalatine fossa and contains the infraorbital neurovascular
structures.
■ The roof, composed of the frontal bone and the lesser wing of the sphenoid,
also forms the base of the anterior cranial fossa.
■ The diameter of the globe exponentially expands during the first 12 months of
age.3 The rate of expansion begins to slow during 12 to 35 months of age and
tapers off by 8 years of age when the diameter is approximately 96% of mature
growth. Orbital dimensions and subsequent bony growth are significantly
correlated with changes in globe diameter.
■ Based on anthropometric soft tissue measurements, Farkas et al.4 determined
that approximately 90% of orbital growth occurs by 5 years of age.
PATHOGENESIS
■ Congenital anophthalmia occurs in the first weeks of gestation during neural
tube formation when the neuroepithelium of the ventral forebrain fails to
invaginate and form the optic vesicles.
■ Etiology
• Primary genetic defect
∘ SOX2
∘ PAX6
∘ CHX10
∘ GDF6
• Gestational
∘ Rubella
∘ Varicella
∘ Herpes simplex virus
∘ Cytomegalovirus

∘ Intrauterine exposure to thalidomide
∘ Vitamin A deficiency
■ Incidence
• The reported incidence ranges from 0.2 to 1.5 per 10 000 births.
■ Acquired enucleation or evisceration after birth secondary to:
■ Tumor
• Retinoblastoma
• Choroidal melanoma
■ Trauma
■ Infection
NATURAL HISTORY
■ The developing globe is critical for the stimulation of orbital and maxillofacial
growth.
■ Absence of a globe creates a three-dimensional midface hypoplasia of the
skeletal, soft tissue, and adnexal structures.1,2
■ The resulting bony orbit is markedly reduced in volume and dimensions of the
aperture.
■ Horizontal and vertical zygomaticomaxillary development is subsequently
affected with ipsilateral deficiencies manifested as a canted occlusal plane, loss
of facial width, and projection of the malar prominence.
■ The hypoplastic skeletal foundation creates significant soft tissue asymmetries
with an inferiorly displaced eyebrow and short phimotic eyelids.
■ Adnexal structures are also poorly developed with contraction of the
conjunctiva and fornices.
■ Enucleation in early childhood results in arrest of symmetric orbital growth.
The severity of hypoplasia depends on the age at surgery as the orbit rapidly
expands during the first 5 years of life.
■ Without restoration of intraorbital volume and pressure, through autologous or
alloplastic material, the socket and fornices contract, which compromises the
ability to wear a prosthesis.
■ As the infant progresses through childhood to adolescence, facial asymmetries
will become more pronounced.

Frontal bone Ethmoid bone Lacrimal bone Nasal bone Infraorbital foramen Maxillary bone A Sphenoid bone, greater wing Superior orbital fissure Anterior clinoid process Optic canal Anterior cranial fossa Frontal bone Ethmoid bone Lacrimal bone Maxillary bone Maxillary sinus -Supraorbital foramen -Fossa of the lacrimal gland - Frontozygomatic suture -Zygomatico- temporal foramen - Lateral orbital tubercle of Whitnall Zygomaticofacial foramen Zygomatic bone Frontal bone Frontal sinus Lateral orbital tubercle of Whitnall - Zygomatic bone - Inferior orbital fissure Maxillary bone Maxillary sinus Anterior ethmoidal foramen Posterior ethmoidal foramen Optic canal Pituitary fossa Sphenoid bone - Palatine bone Pterygopalatine fossa

FIG 1 • A. Frontal view of the orbital bones. B,C. Lateral
and medial walls of the orbit.
PATIENT HISTORY AND PHYSICAL FINDINGS
■ Anophthalmia or microphthalmia is predominantly unilateral but can be
bilateral (FIG 2).
■ Children with severe microphthalmia may retain potential for vision, and a
complete examination is critical. A pediatric ophthalmologist should assess
vision, including electrodiagnostic studies.
■ Flash visual evoked potentials establish optic nerve dysfunction and the
presence of residual vision.
■ Electroretinogram may identify retinal dysfunction.
■ In unilateral cases, the contralateral globe, lens, and optic nerve must be
examined for additional anomalies such as a coloboma, cataract, glaucoma,
retinal dystrophy, or optic nerve hypoplasia.
■ The lacrimal system may be dysfunctional ranging from canalicular stenosis to
nasolacrimal duct obstruction that requires dacryocystorhinostomy.
■ A complete assessment of the child must be undertaken to determine the
presence of associated systemic abnormalities including craniofacial, cardiac,
genital, respiratory, neurologic, or metabolic.
■ Anophthalmia-plus syndrome includes anophthalmia, cleft lip and palate,
facial clefts, and sacral neural tube defects.
IMAGING
■ Diagnostic imaging should be obtained to evaluate the intraorbital contents.
■ Ultrasound of the orbit may determine whether an ocular remnant or cyst is
present. Simultaneous renal ultrasound is recommended due to the association
of ophthalmic and renal anomalies.
■ Computed tomography (CT) precisely delineates the bony anatomy but poorly
defines the soft tissue structures and exposes the child to radiation. The
implementation of low-dose radiation protocols has significantly lowered this
theoretical risk (FIG 3).

FIG 2 • Six-month-old patient with right unilateral
congenital microphthalmia.
■ Magnetic resonance imaging (MRI) provides superior detail of intraorbital soft
tissues and intracranial visual pathways and screens for brain anomalies.
■ MRI has the additional advantage of avoiding radiation exposure; however,
sedation is required in order to obtain a high-quality study in a young child.
DIFFERENTIAL DIAGNOSIS
■ Clinical congenital anophthalmia refers to a phenotypic spectrum of blindness
due to a developmental defect of the globe:
■ Anophthalmia: the complete absence of ocular tissue
■ Microphthalmia: the presence of a hypoplastic, rudimentary cyst; ocular
remnant; or globe
■ The distinction is not clinically relevant as the management does not differ and
the terms are frequently interchanged.
NONOPERATIVE MANAGEMENT
■ Multidisciplinary team care is essential for the management of affected
children and includes plastic surgery, pediatric ophthalmology, prosthetic
ocularist, optometry, genetics, and social work.
■ In unilateral cases, vision in the contralateral unaffected eye must be protected
with regular ophthalmologic examinations and safety glasses to prevent
trauma.
■ Conventional treatment of anophthalmia is initiated in the first few weeks of

life by serial placement of progressively enlarging custom-made static acrylic,
glass, or silicone intraorbital and scleral conformers. Although this technique
can enlarge the orbit, it is not without several limitations including the
following:
FIG 3 • Follow-up CT scan showing the appropriate
position of the intraorbital tissue expander.
■ The treatment plan requires significant dedication from the family because
frequent office visits and examinations under anesthesia are necessary.
■ Serial static conformers provide minimal stimulation for orbital growth, and
despite frequent upsizing, development lags behind the contralateral
unaffected side.
■ If the conformer is not worn for a prolonged time, the socket will undergo
contraction.
SURGICAL MANAGEMENT
■ Orbital expansion is indicated for the correction of asymmetry in patients with
congenital or early-age acquired anophthalmia before the completion of orbital
growth.
■ The technique is designed to stimulate orbital growth by recreating the
pressure that would ordinarily be exerted by the globe. Physiologic pressure
allows for orbital expansion and supraphysiologic pressure will lead to
accelerated, or catch-up, growth to correct asymmetries.

■ Various minimally invasive techniques have been described to avoid the
morbidity of orbital osteotomies.
■ Autologous techniques, such as dermal-fat grafts and free tissue transfer,
have been described but are limited due to an unpredictable stimulus for
orbital growth.5,6 Graft resorption secondary to the recipient site’s potential
for revascularization, notably with prior radiation, and hypertrophy secondary
to obesity have been reported.7
■ Tissue expansion is minimally invasive, with controlled gradual expansion to
avoid uncomfortable rapid inflation pressure and the capability to stimulate
accelerated growth of orbital bony and periorbital soft tissue structures to
achieve a reconstruction symmetric to the unaffected side with minimal
complications.8,9
■ Defining the goals of reconstruction and setting realistic expectations is
paramount before proceeding with orbital expansion.
■ The age of the patient is a critical factor when utilizing an orbital expander.
Clinical and experimental studies have examined the effect of increasing
skeletal maturation on the ability to stimulate orbital growth with a tissue
expander. Results have demonstrated that both early and delayed expansion can
generate accelerated, or catch-up, growth; however, delayed expansion has a
significantly decreased ability to reduce orbital hypoplasia and asymmetry.
■ Orbital expansion should begin as early as possible and must be initiated
before complete synostosis of the orbital sutures.6
■ The precise upper age limit has not been well defined, but a study has shown
that the efficacy of orbital expansion may be compromised as early as 4 years
of age.9
■ Proper patient selection is essential. The surgeon should ensure that the
patient’s family will be compliant with regular follow-up in the clinic for
monthly orbital expansion.
■ The patient’s family must also understand that it is a gradual process to expand
the relatively inelastic bones of the orbit. This is in stark contrast to soft tissue
expansion in which elastic structures are rapidly expanded. Complete
correction of orbital asymmetries may require several years with multiple
exchanges to larger expander sizes.
■ Orbital expansion should be approached with caution in patients with acquired
anophthalmia who have previously undergone periorbital radiation as the
complication rate may be significantly increased.

■ Maintenance of intraorbital volume and pressure to prevent contraction is
indicated in patients who have completed correction of orbital asymmetries or
those with acquired anophthalmia after skeletal maturity.
■ Alloplastic options, including hydroxyapatite or silicone implants, retain the
potential for motion in a prosthesis if the extraocular muscles are preserved,
but infection and extrusion can be problematic.
■ Autologous options, including dermal-fat grafts or free tissue transfer, can be
utilized, although unpredictable growth remains a concern. Free tissue transfer
has the advantage of a skin paddle to aid in conjunctival or soft tissue
reconstruction.
FIG 4 • A. Inflated silicone expander with remote
microport. B. A larger expander needs to be folded to fit
in an infant orbit, creating pressure points with higher
extrusion rates.
Preoperative Planning
■ After the patient has undergone a thorough ophthalmologic and radiologic
examination, minimal preoperative planning is required for orbital expansion.
■ Estimation of orbital volume can be difficult, and various sizes of expanders
should be available at the time of implantation. Backup expanders should be
present in case of inadvertent puncture.
■ In general, a 1- to 2-mL spherical expander can be utilized in a 3- to 6-
month-old patient (FIG 4A).
■ Selecting the proper sized expander is crucial to minimize potential
complications.

■ If the implant is too large, a fold in the expander can create a flaw in the
integrity of the shell and cause device failure (FIG 4B).
■ Furthermore, a crease can also cause pressure necrosis on the conjunctiva
and subsequently develop into wound breakdown and expander exposure.
■ When deciding between two expanders, placement of the smaller expander
lessens the likelihood of a crease or fold. This does not hinder the
reconstruction as expanders can be overinflated in excess of the manufacturer’s
recommended fill volume or exchanged for a larger size at a later date.
■ A consolidation period of 3 months is strongly recommended between
expander exchanges.
Positioning
■ The patient is positioned supine on the operating table such that the orbit and
temporal and parietal scalp are accessible.
■ Anesthesia should be induced with a secured endotracheal tube because
repositioning and rotation of the head are required during surgery.
■ A gel pad or Mayfield headrest may be used.
■ In a unilateral procedure, the contralateral eye is protected by taping the
eyelids closed and using ophthalmic Betadine to prevent potential corneal
abrasions or chemical injury.
■ All potential pressure points on the body must be padded.
Approach
■ Placement of an orbital expander is approached through the periorbita and
temporal hair-bearing scalp.
T E C H N I Q U E S
■ Exposure and Orbitotomy
■ An incision measuring 2 to 3 cm is made in the temporal hair-bearing skin
(TECH FIG 1A). Superficial to the temporal fascia, a tunnel is created to the
lateral orbital wall and the temporoparietal scalp.
■ The conjunctiva is incised to gain access to the intraorbital contents.
■ If present, enucleation of residual orbital contents can be performed in

conjunction with expander placement.
■ Through an extended lateral canthotomy incision, the lateral orbital wall is
exposed (TECH FIG 1B).
■ A lateral wall orbitotomy is created.
■ Depending on the patient’s age and ossification of the bone, this may be
achieved with a bur hole or a biopsy punch.
TECH FIG 1 • A. An incision is made in the temporal
hair-bearing scalp superficial to the temporal fascia,
creating a tunnel between the lateral orbital wall and
the temporoparietal scalp. B. Through an extended
lateral canthotomy incision, a lateral wall orbitotomy is
created. The orbital expander is anchored through the
orbitotomy to prevent migration.
■ Orbital Tissue Expander and Microport Placement
■ The silicone expander is placed in the orbit with the collar firmly anchored
through the lateral orbital wall (TECH FIG 2A).
■ This prevents expander migration and allows for a controlled expansion
process.
■ The expander is placed in the intraconal, anatomic position of the globe to
recreate the pressure normally exerted on the bone and soft tissue during
development. Subperiosteal placement is avoided as the periosteum is
inelastic and this would prevent a symmetric 360-degree spherical

expansion.
■ Through the temporal incision, a pocket is developed in the temporoparietal
scalp for placement of the remote microport.
■ The remote microport allows for easy access without distorting the scalp
anatomy.
■ A 30-gauge needle is recommended for inflation to create minimal
discomfort and to avoid leakage from the port.
■ The tubing from the expander and microport are joined with a straight
connector (TECH FIG 2B).
TECH FIG 2 • A. Intraorbital placement of silicone
expander. B. Placement of remote microport in the
temporoparietal scalp.
■ Expander Inflation and Closure
■ The expander is inflated with injectable saline and examined for a leak or
crease.
■ As previously mentioned, a fold or crease in the expander must be avoided
as it can cause device failure or conjunctival breakdown and exposure.
■ If a crease is identified, the expander should be inflated additionally.
■ If the crease is not corrected or this causes excessive tension on the
closure, the expander must be exchanged for a smaller size.

■ The conjunctiva is closed in layers with Tenon capsule, if present.
■ The final fill volume of the expander is determined by the tension on the
conjunctival closure. Tension must be minimized to prevent wound healing
complications.
■ A tarsorrhaphy suture is placed at the conclusion of the procedure.
PEARLS AND PITFALLS
Accelerated
growth
■ Expansion should be initiated at the earliest age possible, preferably
within 3 months, and before synostosis of the orbital sutures. Early
age at expansion can achieve accelerated growth and correct orbital
discrepancies.
Controlled
expansion
■ Anchoring the expander through the lateral wall orbitotomy prevents
migration and creates a controlled expansion.
Iatrogenic
puncture
■ A remote port allows for expansion without the patient visualizing
the needle and reduces the risk of iatrogenic puncture.
Exposure
of the
expander
■ Aggressive inflation of the expander should be avoided, especially in
a patient with prior radiation; risk of exposure increases in this
scenario.
■ Choosing a smaller expander prevents exposure because folds or
creases may cause friction or pressure necrosis on the conjunctiva
and lead to wound breakdown.
Upsizing
the
expander
■ A significant consolidation period is required between upsizing
expanders, preferably 3–6 months.
Leakage
■ Leakage from the port or connector may occur. This may happen
when multiperforating the microport or using needles larger than 30
gauge (FIG 5). With leakage, inflation volume may not represent the
actual intraexpander volume. The port alone may be replaced without
exchanging the entire tissue expander.
POSTOPERATIVE CARE
■ Placement of an orbital expander may be performed as an outpatient
procedure.

■ Patients return to clinic 4 weeks postoperatively to begin the expansion
process, which then proceeds on a monthly basis.
■ Topical anesthetic cream is applied directly over the port site by the parents 1
hour prior to the clinic visit.
■ Placement of the microport in the temporoparietal scalp allows for expansion
in the clinic without the patient visualizing the needle. This avoids an anxious,
moving patient and can prevent iatrogenic rupture.
■ Inflation of the expander is terminated when the patient displays physical signs
of intolerance.
OUTCOMES
■ Multiple investigators have explored orbital expansion for anophthalmia in an
animal model. The data demonstrate a direct relationship between intraorbital
pressure and orbital growth. Expansion at physiologic pressure stimulated
normal orbital growth, but supraphysiologic pressure accelerated growth.
■ Expanders have shown a statistically significant increase in orbital volume
when compared to static conformers of increasing size.10
FIG 5 • Multiperforated microport showing leakage of
the injected saline.
■ Expanders have also exerted trophic effects on periorbital soft tissue and
reduced the degree of zygomaticomaxillary hypoplasia.10,11

■ There are limited clinical data in the literature except for case series due to the
rarity of the condition.
■ Existing data support orbital expansion as a safe and effective procedure to
correct the asymmetries of anophthalmia and microphthalmia.8,12,13
■ Additional data also indicate that expansion should be initiated at the earliest
possible age as the rate of accelerated growth is inversely proportional to age.9
COMPLICATIONS
■ Unplanned expander removal
■ Exposure
■ Rupture
■ Infection
■ Leakage
■ Inadequate correction
■ Residual asymmetry
■ Further soft tissue reconstruction
REFERENCES
1. Gundlach KK, Guthoff RF, Hingst VH, et al. Expansion of the socket and
orbit for congenital clinical anophthalmia. Plast Reconstr Surg.
2005;116:1214-1222.
2. Krastinova D, Kelly MB, Mihaylova M. Surgical management of the
anophthalmic orbit, part 1: congenital. Plast Reconstr Surg. 2001;108:817-826.
3. Escarabage GK Jr, Dutton JJ. Age-related changes in the pediatric human
orbit on CT. Ophthal Plast Reconstr Surg. 2013;29:150-156.
4. Farkas LG, Posnick JC, Hreczko TM. Growth patterns in the orbital region: a
morphometric study. Cleft Palate Craniofac J. 1992;29:315-318.
5. Heher KL, Katowitz JA, Low JE. Unilateral dermis-fat graft implantation in
the pediatric orbit. Ophthal Plast Reconstr Surg. 1998:14(2):81-88.
6. Heinz GW, Nunery WR, Cepela MA. The effect of maturation on the ability to
stimulate orbital growth using tissue expanders in the anophthalmic cat orbit.
Ophthal Plast Reconstr Surg. 1997;13(2):115-128.
7. Quaranta-Leoni FM, Sposato S, Raglione P, Mastromarino A. Dermis-fat graft
in children as primary and secondary orbital implant. Ophthal Plast Reconstr
Surg. 2016;32:214-219.
8. Dunaway DJ, David DJ. Intraorbital tissue expansion in the management of
congenital anophthalmia. Br J Plast Surg. 1996;49(8):529-535.

9. Morrow BM, Albright WA, Neves RI, et al. Orbital expansion for congenital
anophthalmia may be achievable in infancy but not in childhood. J Craniofac
Surg. 2016;27:1642-1646.
10. Buchman SR, Bartlett SP, Wornom IL, Whitaker LA. The role of pressure on
regulation of craniofacial bone growth. J Craniofac Surg. 1994;5:2-10.
11. Eppley BL, Holley S, Sadove AM. Experimental effects of intraorbital tissue
expansion on orbitomaxillary growth in anophthalmos. Ann Plast Surg.
1993;31:19-26.
12. Grossman MD, Mohay J, Roberts DM. Expansion of the human
microphthalmic orbit. Ophthalmology. 1999;106: 2005-2009.
13. Tse DT, Abdulhafez M, Orozco MA, et al. Evaluation of an integrated orbital
tissue expander in congenital anophthalmos: reports of preliminary clinical
experience. Am J Ophthalmol. 2011;151: 470-482.

19
CHAPTER
Section III: Maxillary
Surgery
Surgically Assisted Rapid
Palatal Expansion (SARPE)
Omri Emodi, Nezar Watted, and Adi Rachmiel
DEFINITION
■ Maxillary transverse deficiency can be treated either orthodontically or
surgically using rapid palatal expansion (RPE). This technique, which involves
enlarging the maxillary dental arch and the palate (roof of the mouth) to re-
establish balance between the width of the jaws through use of an orthodontic
device, forces open the palatal bones via a screw mechanism that is turned
daily.1,2
■ In children and adolescents, conventional orthodontic RPE has been successful
when applied prior to palatal suture closure.3
■ In skeletally mature patients, the possibility of successful maxillary expansion
decreases as sutures close and resistance to mechanical forces increase.4
■ Indications for RPE include5,6 the following:
■ To increase maxillary arch width, which corrects a posterior crossbite
■ To widen the maxillary arch as a preliminary procedure prior to LeFort I
advancement
■ To provide space for crowded maxillary dentition
■ To widen maxillary hypoplasia associated with clefts of the palate prior to
bone grafting1–3
ANATOMY
■ Relevant anatomic regions that contribute to resistance:

■ Anteriorly—piriform aperture pillar
■ Laterally—zygomatic buttress
■ Posteriorly—pterygoid junction
■ Medially—midpalatal suture
■ Important anatomical landmarks:
■ Greater palatine neurovascular bundle—passes through the palatine bone in
the posteromedial wall of the maxillary sinus
■ Nasal mucosa—located medially and should be preserved
■ Root of the canine—apex of the root is more superiorly positioned compared
to other teeth and should be avoided when performing the horizontal
osteotomy.
PATIENT HISTORY AND PHYSICAL FINDINGS
■ Physical examination reveals a constricted upper arch, with a narrow and high
palatal vault.
■ Maxillary dental crowding is present in combination with midface hypoplasia.
IMAGING AND OTHER DIAGNOSTIC STUDIES
■ Posteroanterior cephalogram (interjugal distance, intermolar width)
FIG 1 • Cone-beam computer tomography showing
maxillary transverse deficiency.

■ Cone-beam computer tomography (CBCT; FIG 1)
■ Cast models of the upper and lower jaws: In cases of maxillary transverse
deficiency, a deep curve of Wilson in the lower dentition may mask the
maxillary transverse constriction.
■ Assessing the models in the articulator
DIFFERENTIAL DIAGNOSIS
■ Unilateral or bilateral posterior crossbite (FIG 2A)
■ Narrow tapering maxillary arch form (FIG 2B)
■ Narrow and high palatal vault
■ Excessive buccal corridors (space between the teeth and the corners of the
mouth)
■ Maxillary dental crowding, when extractions are not indicated
■ Maxillary hypoplasia associated with clefts of the palate
NONOPERATIVE MANAGEMENT
■ RPE without surgical intervention can usually be applied until the age of 15.
SURGICAL MANAGEMENT
Preoperative Planning
■ Dental casts
■ Preoperative CBCT or panoramic x-ray as well as posteroanterior
cephalograms (see FIG 1)
■ The Hyrax device for expansion is applied by the orthodontist before surgery
in cases where a tooth-borne device is required. A bone-borne device is placed
intraoperatively.

FIG 2 • A. Bilateral posterior crossbite with anterior
open bite. B. Narrow maxillary arch form with dental
crowding.
Positioning
■ The patient is placed in the supine position.
■ Nasal intubation is used to allow intraoral access.
■ IV muscle relaxant is administered for better mouth opening during the case.
■ A bite block is placed and maintained throughout surgery for easier mouth
opening.
■ Local anesthesia, such as lidocaine 2% combined with adrenaline for
vasoconstriction, is administered.
T E C H N I Q U E S
■ Exposure
■ A bilateral horizontal incision is made within the maxillary vestibule, 2 to 3
mm above the attached mucosa, between the lateral incisor anteriorly and the
first molar posteriorly, keeping the midline frenulum attached for better
aesthetic results (TECH FIG 1).
■ Develop exposure of the lateral maxilla from the central incisors toward the
pterygomaxillary junction posteriorly.
■ Separate the nasal mucosa from the lateral nasal wall using a periosteal or

Freer elevator.
TECH FIG 1 • Horizontal incision is made in the
maxillary vestibule 2 to 3 mm above the attached
mucosa.
■ Osteotomies
■ Using a reciprocating saw, a lateral, horizontal maxillary osteotomy is made
on the lateral maxilla at least 5 mm above the apex of the teeth at the level of
the nasal floor; the osteotomy extends from the pterygoid plate posteriorly
toward the lateral wall of the nose anteriorly.
■ Avoid damage to the canine apex, which is higher than the other tooth roots
(TECH FIG 2A).
■ The nasal septum and the nasal wall should be separated from the palate
using a fine osteotome to protect the nasal mucosa.
■ A sagittal osteotomy is performed between the central incisors (TECH FIG
2B).
■ A thin osteotome is introduced between the two central incisors and an
osteotomy of the midpalatal suture is performed.
■ Avoid perforating the palatal mucosa by palpating the mucosa with a finger
during the osteotomy. The osteotomy is continued until independent
movement of both lateral maxillary segments is accomplished.

■ The pterygomaxillary fissure is osteotomized using a curved osteotome.
■ This step is optional due to the risk of causing uncontrolled bleeding from
the internal maxillary artery or the pterygoid venous plexus. If it is
performed, it is critical to position the osteotome correctly, in an inferior
and medial position (TECH FIG 2C).
■ The desired osteotomies are demonstrated in TECH FIG 2D,E.

TECH FIG 2 • A. A lateral horizontal maxillary
osteotomy on the lateral maxilla is made at least 5 mm
above the apex of the teeth. B. A thin osteotome is
introduced between the two central incisors and
osteotomy of the midpalatal suture is carried out. C.
The pterygomaxillary fissure is osteotomized by a
curved osteotome. This procedure is optional. D,E.

Illustration of SARPE design.
■ Alternate Technique: Bilateral Transverse L-
shaped Maxillary Osteotomy
■ In cases in which there is need to avoid displacement of the premaxillary
segment, an L-shaped osteotomy is performed bilaterally.
■ Osteotomies are made laterally from the pterygoid plate posteriorly to a
position above the roots of the second incisor (TECH FIG 3), continuing
with a vertical osteotomy between the lateral incisor and canine teeth toward
the horizontal osteotomy.6
TECH FIG 3 • Inverted L osteotomy design, frontal (A)
and occlusal (B) views.
PEARLS AND PITFALLS
Orthodontic
appliance
■ The Hyrax should be activated before closing the mucosa. The
opening of the midpalatal suture should be directly viewed.
Nasal
apparatus
■ It is critical to release the nasal septum from the maxilla during the
midpalatal osteotomy to avoid septal deviation.
Bleeding
■ Osteotomy of the pterygoids is optional due to the risk of

iatrogenic injury to the internal maxillary artery and pterygoid
venous plexus. Positioning the osteotome correctly, in an inferior
and medial position, is critical.
■ When separating the lateral nasal walls, avoid the descending
palatine vessels posteriorly.
Anesthetic
consideration
■ SARPE can be done under local anesthesia with IV sedation and
without osteotomy of the pterygopalatine suture due to the high
risk of bleeding.
Midline
osteotomy
■ The midline cut carries the potential to damage the roots of teeth,
compromising perfusion to both bone and soft tissues.
POSTOPERATIVE CARE
■ Activation of the device is initiated on the first postoperative day by turning
the device once a day at a rate of 0.3 mm/d (FIG 3A).
■ Postoperative panoramic x-ray, posteroanterior cephalography, or CBCT
should be performed during postoperative expansion (FIG 3B).
■ Following complete bony and dental arch expansion, orthodontic dental
alignment is performed.
OUTCOMES
■ Increased transverse dimension of the maxilla
■ Wide diastema between central maxillary incisors
■ Elimination of dental crowding
FIG 3 • Several weeks after activation of the Hyrax
palatal expander. A. Photo. B. Radiograph.

■ Reduction of wide black buccal corridors (open space between the lateral
aspects of the posterior maxillary teeth) when smiling
■ Improved nasal breathing
COMPLICATIONS
■ Infection
■ Postoperative bleeding can also occur up to 3 weeks postoperatively, due to
injury of the greater palatine vessels or venous plexus.
■ Periodontal recession
■ Loss of tooth vitality at the osteotomized area
■ Detachment of the orthodontic appliance
■ Asymmetrical expansion
■ Nasal septal deviation2,3
REFERENCES
1. Banning LM, Gerard N, Steinberg BJ, Bogdanoff E. Treatment of transverse
maxillary deficiency with emphasis on surgically assisted-rapid maxillary
expansion. Compend Contin Educ Dent. 1996;17:170, 4-8.
2. Bell RA. A review of maxillary expansion in relation to rate of expansion and
patient’s age. Am J Orthod. 1982;81:32-37.
3. Chrcanovic BR, Custodio AL. Orthodontic or surgically assisted rapid
maxillary expansion. Oral Maxillofac Surg. 2009;13:123-137.
4. Glassman AS, Nahigian SJ, Medway JM, Aronowitz HI. Conservative
surgical orthodontic adult rapid palatal expansion: sixteen cases. Am J Orthod.
1984;86:207-213.
5. Suri L, Taneja P. Surgically assisted rapid palatal expansion: a literature
review. Am J Orthod Dentofacial Orthop. 2008;133:290-302.
doi:10.1016/j.ajodo.2007.01.0216.
6. Anttila A, Finne K, Keski-Nisula K, et al. Feasibility and long-term stability
of surgically assisted rapid maxillary expansion with lateral osteotomy. Eur J
Orthod. 2004;26:391-395.

20
CHAPTER
Premaxillary Segment
Setback
Omri Emodi
DEFINITION
■ Orofacial clefts (OFCs) are the most common birth defect with a prevalence of
17 in every 10 000 live births.1
■ OFCs are most common in Amerindian and Asian populations (15–36/10 000)
and least common among African populations (5/10 000).2,3
■ OFCs involving the lip have a male-to-female ratio of 2:1.
■ Bilateral cleft lip and palate (BLCP) is the most severe of the common OFC
subtypes and represents 1 in 10 patients with clefts of the lip.
■ Subjects with BCLP usually present with maxillary retrognathism, a smaller
mandible with an obtuse gonial angle, greater anterior upper and lower facial
heights, and retroclined maxillary incisors.
■ The premaxilla associated with BCLP may present in multiple positions,
including severe protrusion (FIG 1).
ANATOMY
■ The nasomaxillary process (including the nose and premaxilla) is separated
from the lateral maxillary segments.
■ There is significant variation in the position of the premaxilla in patients with
BCLP.4
■ It may be in correct position in relation to the lateral maxillary segments.
■ The premaxilla may also project anteriorly or rotate up under the nose, with
significant deviation to either side.
■ Severe protrusion of the premaxilla is possible.

FIG 1 • A child with protruded premaxilla.
■ The prolabium (soft tissue on the premaxilla) is composed of skin,
subcutaneous tissue, and fat and is without a muscle layer.
■ Vascular and neural findings include the following:
■ The pterygopalatine portion of the maxillary artery provides major branches
to the maxilla, teeth, palate, and linings of the nose and sinuses.
■ The posterior septal artery alone cannot fully meet the needs of the
premaxilla and requires a complementary supply from the prolabial
circulation (FIG 2).
PATHOGENESIS
■ The embryological development of the upper lip and nose requires a sequence
of complex, genetically programmed events:
■ Fusion of the five major facial prominences occurs between the 3rd and 8th
weeks of gestation.
■ Lip development occurs between the 3rd and 7th weeks.
■ Multiple genetic mutations disrupt facial development, resulting in OFCs.1–3
PATIENT HISTORY AND PHYSICAL FINDINGS
■ BLCP patients with protrusive premaxillae may present at several time points

where treatment can be initiated.
■ Prior to lip repair, presurgical orthodontics may be used to retrocline the
premaxilla.5
FIG 2 • Anatomical description of the blood supply to
the premaxilla in patients with bilateral cleft lip and
palate. Branches from the dorsal nasal artery and the
columellar artery contribute to the blood supply of the
premaxilla.
■ After lip repair, when the patient may require surgical setback of the
premaxilla as an isolated procedure.
■ During mixed dentition (6–8 years of age), when the premaxillary setback
can be performed with a bone grafting procedure.6
■ At the time of skeletal maturity, when orthognathic surgery is planned.
Premaxillary setback should be avoided at the time of orthognathic surgery;
the setback should be completed prior to orthognathic surgery.
■ In an adult, where premaxillary setback can be performed with lip repair.7
NONOPERATIVE MANAGEMENT

■ Nasoalveolar molding (NAM)7
■ A presurgical orthopedic device can be used to guide the lateral alveolar
ridges and premaxillary segment into an improved arch form.
■ Shortly after birth, impressions of the upper jaw and the nose are made.
These impressions serve to construct the orthodontic plate. The purpose of
this plate is to retrocline and symmetrically position the premaxillary
segment.
■ Weekly adjustments are required for maximal effectiveness of the presurgical
appliance.
FIG 3 • Cast model before (A) and after (B) ostectomy.
C. Demonstration of the appliance on the cast model for
postoperative fixation.
■ This process needs to be completed by 4 to 6 months of age. After this time,
the premaxillary segment becomes ossified and cannot be manipulated by
NAM.

SURGICAL MANAGEMENT
Preoperative Planning
■ A dental impression of the upper jaw is taken using silicone material.
■ A cast model is fabricated from the impressions (FIG 3A).
■ Mock surgery is performed on the model as follows:
■ The premaxilla is osteotomized.
■ The protruded segment is repositioned into the desired location for correction
of the skeletal disorder (FIG 3B).
■ An orthodontic fixation appliance is fabricated to stabilize the segment in its
new position during healing (FIG 3C).
Positioning
■ The child is positioned supine on the operating room table, at 90 degrees from
the anesthesia staff.
■ A shoulder roll is placed for neck extension.
■ An oral RAE tube is used for intubation, and a bite block is used to maintain
the mouth in an open position during surgery.
T E C H N I Q U E S
■ Premaxillary Segment Setback
■ The child’s protruded premaxilla is exposed using an intraoral approach to
the vomer.
■ The blood supply to the premaxilla must be maintained to prevent vascular
necrosis of the segment.
■ Infiltrate local anesthetic (2% lidocaine with 1:1 000 000 epinephrine) to the
upper vestibule and vomer.
■ A vertical incision is made from the anterior to the posterior vomer using a
no. 15 blade (TECH FIG 1A).
■ The nasal layer is separated from the vomer to provide complete exposure of
the underlying cartilage.
■ A 10- to 15-mm ostectomy of the vomer-maxilla junction is performed at the
oral base of the vomer. It should be narrow at the top—facing the nasal side

—and wider at the base, shaped like a triangle (TECH FIG 1B).
■ The triangular space will be closed once the premaxilla is down-rotated
and aligned to the posterior aspect of the vomer.
■ Keep the buccal mucosa intact to maintain adequate blood supply to the
osteotomized premaxilla.
■ Create perfect alignment between the two sides of the reduced vomer.
■ The premaxilla is then fixed with the custom-made orthodontic appliance
with dental wires to adjacent teeth (TECH FIG 1C).
■ In the absence of teeth for fixation of the orthodontic appliance, a K-wire is
used to fixate the premaxilla to the vomer.
■ The mucosa covering the vomer is then sutured with a 4.0 Vicryl suture,
providing watertight coverage of the vomer to reduce infection in the area of
the ostectomy.
■ Mild pressure should be applied to the premaxilla to determine the degree
of stabilization.
■ If lip repair is planned, it is completed in traditional fashion.8
■ The custom-made orthodontic appliance with dental wires is left in place for
3 months.
TECH FIG 1 • A. Surgical exposure of the osteotomy
region. B. Ostectomy of the vomerine segment. C.
Postoperative results with the premaxilla rigidly fixed
with appliance after repositioning.

PEARLS AND PITFALLS
Approach
■ Consideration must be given to the blood supply of the premaxilla.
If this is injured, loss of the premaxilla is likely.
■ The surgeon should approach the premaxilla intraorally with the use
of a Dingman retractor.
■ Surgical exposure of the vomer should be in proximity to the
premaxilla.
■ Nasal layer closure should be watertight for appropriate healing.
Fixation
■ Rigid fixation of the osteotomized premaxilla is crucial for
appropriate healing.
■ In the absence of teeth to fixate the orthodontic appliance to the
premaxilla, a K-wire can be used to fixate the premaxilla to the
vomer.
Stabilization
■ Lip closure can be performed routinely after the premaxilla is
repositioned.
■ The premaxilla may remain mobile without fixation until bone
grafting to the maxillary cleft.
POSTOPERATIVE CARE
■ All patients maintain a strict soft diet for 12 weeks.
■ Oral hygiene is maintained with frequent mouthwashes and gentle brushing.
■ The orthodontic fixation appliance should be left in place for 16 weeks
postoperatively.
■ After removing the orthodontic fixation appliance, a continuous orthodontic
arch wire should be worn by the patient.
OUTCOMES
■ Premaxillary setback with accurate positioning of the premaxilla leads to:
■ Appropriate maxillary arch form
■ Improved success of bone grafting procedures
■ Improved lip cosmesis
■ Improved overall oral function and dental aesthetics5–7
COMPLICATIONS
■ Infection

■ Avascular necrosis of the premaxillary segment
■ Mobility of the premaxilla
■ Iatrogenic damage to tooth buds in the premaxilla6,7
REFERENCES
1. Canfield MA, Honein MA, Yuskiv N, et al. National estimates and
race/ethnic-specific variation of selected birth defects in the United States,
1999-2001. Birth Defects Res A Clin Mol Teratol. 2006;76(11 suppl):747-756.
2. Vanderas AP. Incidence of cleft lip, cleft palate, and cleft lip and palate among
races: a review. Cleft Palate J. 1987;24(3 suppl):216-225.
3. Croen LA, Shaw GM, Wasserman CR, Tolarova MM. Racial and ethnic
variations in the prevalence of orofacial clefts in California, 1983-1992. Am J
Med Genet. 1998;79(1 suppl):42-47.
4. Friede H, Johanson B. A follow-up study of cleft children treated with vomer
flap as part of a three-stage soft tissue surgical procedure: facial morphology
and dental occlusion. Scand J Plast Reconstr Surg. 1977;11:45-57.
5. Grayson BH, Cutting CB. Presurgical nasoalveolar orthopedic molding in
primary correction of the nose, lip, and alveolus of infants born with unilateral
and bilateral clefts. Cleft Palate Craniofac J. 2001;38(3 suppl):193-198.
6. Carlini JL, Biron C, Gomes KU, Da Silva RM. Surgical repositioning of the
premaxilla with bone graft in 50 bilateral cleft lip and palate patients. J Oral
Maxillofac Surg. 2009;67(4 suppl):760-766.
7. Lee UL, Cho JB, Choung PH. Simultaneous premaxillary repositioning and
cheiloplasty in adult patients with unrepaired bilateral cleft lip and palate. Cleft
Palate Craniofac J. 2013;50(2 suppl):231-236.
8. Kim SK, et al. Mulliken method of bilateral cleft lip repair: anthropometric
evaluation. Plast Reconstr Surg. 2005;116(5 suppl):1243-1251.

21
CHAPTER
Le Fort I Osteotomy and
Advancement
Kathlyn K. Powell, Ahmed Elsherbiny, and John H. Grant III
DEFINITION
■ A procedure that involves cutting and repositioning the maxilla to the correct
position
■ It is one of the most common procedures used to correct maxillary dentofacial
deformities including size, position, orientation, shape, and/or symmetry.
■ Often performed with corrective mandibular ramus surgery such as a bilateral
sagittal split osteotomy (BSSO)
■ Corrects in three planes: vertical, horizontal, and transverse

FIG 1 • Osseous anatomy of maxilla: anterior (A), lateral
(B), and basal oblique (C) views.
ANATOMY
Osseous Structures
■ In the anterior view of the skull, the maxilla (FIG 1) forms the piriform
aperture and inferior and medial border of the orbit.
■ The anterior surface of the maxilla is the anterolateral wall of the maxillary
sinus.
■ From the piriform rim to the descending palatine canal, the mean length of
the medial sinus wall is 34 mm; therefore, when creating the osteotomy in the
lateral nasal wall, it should be no further posterior than 25 to 30 mm from the
piriform rim.1
■ The infraorbital foramen is at a variable distance from the inferior orbital rim
and the maxillary alveolus, 8 to 20 mm from the nasal floor.

■ The nasolacrimal duct lies within the thin bony wall of the maxillary sinus and
the nasal cavity. The duct ends at the inferior nasal meatus through the valve of
Hasner.
■ The inferior nasal meatus is 11 to 14 mm posterior to the piriform aperture
and 11 to 17 mm above the nasal floor.2
■ The root prominences are occasionally visible through the maxillary alveolar
process.
■ The canine is the longest root.
■ Anterior teeth roots are typically more visible.
■ The maxillary suture at the inferior midline of the piriform aperture forms the
anterior nasal spine (ANS), and the anterior maxilla surrounds the piriform
aperture.
■ Extending posteriorly from the ANS is the nasal crest of the maxilla, which
joins the nasal septum. The nasal floor is formed by the maxillary roof.
■ The piriform rim (nasomaxillary buttress) is a vertical pillar of medial midface
support. The zygomaticomaxillary buttress is the pillar of lateral midface
support.
■ The septal or quadrangular cartilage, the vomer, and the perpendicular plate of
the ethmoid bone articulate in the midline with the nasal crest.
■ The junction of the premaxilla and the maxilla contains the incisive foramen,
which contains the nasopalatine vessels and nerves.
■ The hard palate is formed by the fusion of the palatine processes of the two
hemimaxillae and the horizontal lamina of the palatine bones.
■ The posterior border of the maxilla is the maxillary tuberosity.
■ The pterygomaxillary fissure is located between the maxillary tuberosity and
the pterygoid plates of the sphenoid bones.
■ The descending palatine artery is 10 mm medial to the maxillary tuberosity.1
Muscular Structures
■ The orbicularis oris surrounds the stomion (origin: buccinators, depressor
anguli oris, levator anguli oris).
■ Risorius (origin, fascia overlying the parotid gland; insertion, angle of the
mouth)
■ Zygomaticus major (origin, zygomatic bone; insertion, skin at the angle of the
mouth and orbicularis oris)
■ Zygomaticus minor (origin, zygomatic bone; insertion, skin of the upper lip)

■ Levator labii superioris (origin, maxilla; insertion, skin of the upper lip)
■ Levator labii superioris alae nasi (origin, frontal process of the maxilla;
insertion, skin of the upper lip)
■ Levator anguli oris (origin, maxilla; insertion, skin of the upper lip)
■ Levator labii superioris alaeque nasi (origin, upper frontal process of the
maxilla; insertion, upper lip and ala of the nose)
■ Depressor septi (origin, incisive fossa of the maxilla; insertion, base of the
columella and the nasal septum)
■ Nasalis muscles (origin, maxilla; insertion, alar cartilage)
■ Medial fibers blend with depressor septi.
■ Responsible for compression and dilation of nares
■ Primary muscle in alar base cinch
Vascular Anatomy
■ Arteries
■ Perfusion of the maxilla via three main vessels
• Ascending pharyngeal
• Ascending palatal
• Soft palate vessels
• Must maintain posterior pedicle when sacrificing the descending palatine
arteries
■ Veins
■ Pterygoid plexus
• Surrounds the maxillary artery
• Deep to the lateral pterygoid muscle
■ Pterygoid plexus drainage
• Drains to the maxillary vein
• Drains to the deep facial vein and then the facial vein
• Drains to the cavernous sinus through the foramen ovale
• Drains to the middle meningeal veins through the foramen spinosum
PATIENT HISTORY AND PHYSICAL FINDINGS
■ Past medical history, surgical history, allergies, social history, and family
history should be elicited.
■ Patient history should include questions regarding difficulty chewing food,

headaches, temporomandibular joint dysfunction (TMD), speech, growth, and
breathing.
■ Growth evaluation may include the following:
■ Serial physical examinations
■ Serial cephalometric radiographs
■ A hand-wrist film
■ Evaluation of maturation of vertebrae on a lateral cephalometric radiograph
■ TMJ examination
■ Examine muscles of mastication of TMJ capsule for tenderness to palpation.
■ Examine for clicking, popping, or crepitus.
■ Examine for excursive movements, protrusion, and maximal incisal opening.
■ Examine for deviation upon opening.
■ Skeletal examination
■ Vertical orbital dystopia
■ Measure intercanthal distance.
■ Placement of nose in relation to facial midline
■ Transverse dimension
• Maxillary midline in relation to facial midline
• Mandibular midline in relation to maxillary midline and facial midline
• Chin point in relation to facial midline
• Maxillary occlusal plane and cant in relation to the maxillary canine teeth
• Mandibular occlusal plane level vs canted
• Mandibular angles level vs canted
• Maxillary arch width (evaluate utilizing handheld dental models)
■ AP dimension
• Overjet
• Nasolabial angle
• Labiomental fold
• Chin position
• Profile
■ Vertical dimension
• Facial thirds
• Maxillary incisor length
• Maxillary incisor show at rest and high smile
• Gingival show at rest and high smile

■ Dental examination
■ Overall dental health
■ Missing teeth
■ Presence of third molars
■ Overbite
■ Overjet
■ Angle class of occlusion
■ Arch width (evaluate utilizing handheld dental models)
■ Curve of Spee
■ Dental decompensation
■ Periodontal health
■ Soft tissue examination
■ Upper lip thickness and length
■ Nasolabial angle
■ Nasal tip rotation
■ Patients with maxillary deficiency often appear to have a retruded upper lip,
flat malar eminences, deficiency in the infraorbital rims as well as paranasal
sinuses, inadequate tooth show, and a prominent chin relative to the midface
■ Patients have a “psuedoprognathism” with reverse anterior overjet.
■ Patients with vertical maxillary excess (VME) have a long face with excessive
gingival show
■ Mouth breathing is common.
■ Class II malocclusion is common.
IMAGING
■ Panoramic radiograph should be examined for the following:
■ Health of dentition
■ Presence of third molars
■ Pathology
■ Health of the temporomandibular joint
■ Presence of hardware from previous facial surgery
■ Lateral cephalometric radiograph with the patient’s lips relaxed and the
mandible in centric relation
■ Assess the anteroposterior (AP) position of the maxilla.
■ Assess the AP position of the mandible.
■ Assess the AP discrepancy between the maxilla and the mandible.

■ Assess the maxillary incisor inclination.
■ Assess the mandibular incisor inclination.
■ Assess the facial type.
■ Assess the chin.
■ Preoperative profile, frontal (smiling and rest), and occlusal photographs
should be obtained.
■ Dental models made of stone casts or digital scans are used to evaluate the
dentition as well as to establish the new occlusion.
■ Cone beam computed tomography (CBCT) or computed tomography (CT) is
done for virtual surgical planning (VSP) and/or complex asymmetry cases.
■ PA cephalometric radiograph may be needed in complex cases if CBCT or CT
is not an option.
NONOPERATIVE MANAGEMENT
■ Orthodontic camouflage is an option for nonoperative management if the
deficiency falls within the envelope of orthodontic treatment as described by
Proffit.3
SURGICAL MANAGEMENT
Preoperative Planning
■ Panoramic dental x-ray, cephalometric analysis, and/or cone beam CT should
be reviewed.
■ Model surgery or VSP should be performed in order to determine the most
appropriate movements of the maxilla.
■ A surgical splint will be fabricated from the model surgery or virtual surgical
planning.
■ The need for a bone graft for stability should be determined.
■ Autogenous bone should be harvested prior to the start of the Le Fort I
osteotomy.
■ Allogenic bone is used frequently as well.
Positioning
■ A standard nasotracheal intubation is performed with a Nasal RAE
endotracheal tube.
■ The tube is secured with a headwrap over the forehead. This brings the tube
out of the operative site (FIG 2).

■ The eyes are lubricated and covered with Tegaderm.
■ The patient is placed supine with the head of bed slightly elevated.
■ The arms are tucked at the patient’s side and padded in standard fashion.
Approach
■ An upper buccal sulcus incision with lateral back cut has the advantage of
better preservation of blood supply with sufficient access when compared to
the traditional longer incision.
■ A vertical incision up the zygomatic buttress improves both vascularity and
access.
FIG 2 • Fixation of the endotracheal tube.
T E C H N I Q U E S
■ Preparation and External Reference
■ The patient is prepped and draped with four towels and a head and neck
drape.
■ The mouth is thoroughly irrigated with chlorhexidine gluconate 0.12% oral

rinse.
■ The orthodontic appliances are carefully examined. The surgeon should
know which teeth have bands and brackets and if any brackets are missing.
This is in the event that brackets are dislodged during the case. The surgeon
will know to look for them and not inadvertently leave them in the wound.
This is particularly important when there is a mandibular vestibular incision
for a simultaneous sagittal split osteotomy.
■ If possible, hypotensive anesthesia with a MAP less than 60 should be
performed when the maxilla is down-fractured.
■ Local anesthesia with epinephrine is infiltrated into the maxillary vestibule
from second molar to second molar. Bilateral posterior superior alveolar and
greater palatine nerve blocks are administered (TECH FIG 1A).
■ An external reference in addition to directly measuring marks on the bone is
more accurate when the vertical position of the maxilla is going to be
changed.
■ A 0.035-inch K-wire is placed in the glabella (nasal bone) as an external
stable reference. Soft tissue markers are not accurate.
■ A measurement from the K-wire to the maxillary arch wire at the central
incisors is recorded utilizing a Boley gauge (TECH FIG 1C).
■ The soft tissue midline is marked on the upper lip and verified with the
dental midline (TECH FIG 1B).

TECH FIG 1 • A. Greater palatine nerve block given in
the right side. B. External reference placed on the
upper lip midline. C. Glabellar K-wire and Boley
gauge.
■ Incision and Exposure
■ Retraction is performed with two toe-in retractors placed under the upper lip
while resting on the maxilla.
■ A modified maxillary vestibular incision is made in the unattached mucosa 4
to 5 mm above that attached gingiva with guarded needle tip electrocautery
from first molar to first molar (TECH FIG 2A).

■ This preserves a cuff of mucosa, which makes closure easier at the end of
the case.
■ The incision laterally ends with vertical releasing incisions posteriorly to
increase the vascular flap and perfusion of the maxilla while helping
provide adequate visualization (TECH FIG 2B).
■ The soft tissue is reflected, and the piriform rim, lateral maxillary sinus
walls, ANS, infraorbital foramen, and zygomatic buttresses are exposed
(TECH FIG 2C,D).
■ The posterior maxillary sinus wall and the pterygomaxillary junction are
then exposed.
■ A Freer elevator is used to reflect the nasal floor mucosa from the palatine
bone (TECH FIG 2E).

TECH FIG 2 • A. The planned vestibular incision
showing the lateral vertical releasing incision to
preserve cuff of mucosa at the lateral end of the
incision. B. Left end of incision. C. Exposure of
maxilla. D. Exposure around the infraorbital nerve (left

side). E. The start of piriform aperture dissection
(patient’s right side).
■ Lateral Osteotomies
■ A Seldon retractor is placed posterior to the maxilla.
■ A periosteal elevator is placed inside the piriform rim on the osteotomy side.
■ A sagittal saw is used to make a cut at least 3 to 5 mm above the apices of
the teeth and inferior to the infraorbital foramen from the maxillary buttress
to the piriform rim.
■ The horizontal cut starts 3 to 4 mm above the nasal floor at the piriform rim
and runs obliquely as it moves laterally (TECH FIG 3A).
■ The same steps are repeated on the other side.
■ In cleft distraction cases, the osteotomy is made higher and, in a more
horizontal direction, then sharply curved caudally toward the usual pterygoid
osteotomy site. A rigid external device (RED) is used for fixation (TECH
FIG 3B,C).
■ Some surgeons prefer a modified step osteotomy to prevent vertical
impaction with the advancement and feel it may provide better bone
grafting/fixation (TECH FIG 3D).

TECH FIG 3 • A. The anterior maxillary osteotomy is
completed with the saw. B. Difference between the
conventional osteotomy (black, skull right) and the
osteotomy in cleft patients (blue, skull left), which is
higher and more horizontal. C. The pattern of the
anterior maxillary osteotomy in cleft patients. D. The
modified step osteotomy (blue, skull left).
■ Septal Osteotomy and Pterygoid Plate Separation
■ Curved Mayo scissors are used to separate the nasal septum from the
maxillary crest in an anterior to posterior direction (TECH FIG 4A).
■ Keep the tips of the scissors on the palatine bone as they move posteriorly.
■ Place a finger between the soft palate and the endotracheal tube to prevent
cutting the endotracheal tube.
■ Alternative technique (TECH FIG 4B):
■ A guarded V-shaped osteotome is placed at the top of the ANS and is
driven inferiorly and posteriorly along the nasal floor until the septum is
fully separated from the maxillary crest.

■ The chisel will be palpated at the level of the soft palate. The nondominant
index finger is placed posterior to the soft palate.
■ A curved pterygoid osteotome is placed from the lateral side of the
pterygomaxillary junction aiming inferiorly, medially, and anteriorly parallel
to the occlusion plain.
■ A finger is placed in the oral cavity medial to the junction of the hamulus
and the tuberosity to give support and tactile feedback of the progress of the
osteotomy (TECH FIG 4C).
■ A mallet strikes the osteotome to drive it through the pterygoid plates so that
the maxilla is then separated from the pterygoid plates (TECH FIG 4D).
■ Movement of either the pterygoid plate or the chisel is palpated.
■ The chisel should not be driven through the mucosa.
TECH FIG 4 • A. Septal disconnection by curved