Residency · Residency · Oral Maxillofacial Surgery

Le Fort I Osteotomy: Technique and Complications

Overview

The Le Fort I osteotomy is the standard surgical approach for repositioning the maxilla in orthognathic surgery. It allows three-dimensional movement including advancement, setback, impaction, downgrafting, rotation, and cant correction. It can be performed as a single-piece or segmental osteotomy. First described by Cheever in 1864, it was popularized by Obwegeser and refined by Bell and Epker.

Indications

The Le Fort I osteotomy is indicated for maxillary anteroposterior discrepancy (prognathism or retrognathism), vertical maxillary excess (VME) presenting as a gummy smile or long face syndrome, vertical maxillary deficiency (short face), transverse maxillary deficiency (segmental Le Fort I with palatal expansion), maxillary cant (asymmetric vertical position), obstructive sleep apnea (as part of maxillomandibular advancement), cleft lip and palate with maxillary hypoplasia, and post-traumatic maxillary deformity.

Preoperative Planning

Planning includes cephalometric analysis and clinical facial assessment, virtual surgical planning (VSP) or conventional model surgery, fabrication of intermediate splints (for two-jaw cases) and final splints, assessment of the nasal airway, sinus health on CBCT, and septal deviation, dental models with verification of the planned occlusion, and discussion with the orthodontist regarding presurgical decompensation.

Surgical Technique

Anesthesia and Preparation

General anesthesia with nasal endotracheal intubation (RAE tube) is used. A throat pack is placed and the oral cavity is prepped with chlorhexidine or betadine. Local anesthetic with vasoconstrictor (lidocaine with 1:100,000 epinephrine) is injected along the incision line and around the greater palatine foramina, followed by a 7-10 minute wait for vasoconstriction.

Incision and Exposure

A circumvestibular incision is made horizontally in the maxillary vestibular mucosa, 5 mm above the mucogingival junction, extending from first molar to contralateral first molar. A full-thickness mucoperiosteal flap is elevated superiorly to expose the anterior maxillary wall, pyriform rim, infraorbital nerve (which is identified and protected), and zygomatic buttress bilaterally. Subperiosteal dissection continues posteriorly along the zygomatic buttress to the pterygomaxillary junction. Nasal mucosa is elevated from the nasal floor and lateral nasal wall through intranasal dissection. The descending palatine vessels are identified and protected at the junction of the hard and soft palate, marking the posterior limit of the osteotomy.

Osteotomy

The lateral wall osteotomy is a horizontal cut extending from the pyriform rim to the pterygomaxillary junction bilaterally, performed with a reciprocating saw or piezosurgery. The cut is placed above the root apices (typically 5 mm above, at 30-35 mm above the occlusal plane) and below the infraorbital foramen (minimum 5 mm). Bilateral symmetry is essential for proper leveling. The nasal septum osteotomy uses a guarded osteotome to separate the nasal septum from the maxillary crest. The lateral nasal wall osteotomy uses a thin osteotome through the lateral nasal wall in the inferior turbinate region. The pterygomaxillary disjunction uses a curved osteotome (Tessier or Obwegeser type) placed at the pterygomaxillary junction, directed anterosuperior to posteroinferior, with care to avoid misdirection toward the skull base. This step carries the highest hemorrhage risk from the internal maxillary artery and pterygoid venous plexus.

Down-Fracture

After completing all osteotomy cuts, the maxilla is down-fractured using digital pressure or Rowe disimpaction forceps for controlled fracture. Any remaining bony connections are completed with an osteotome. Once mobilized, the maxilla is attached only by the palatal soft tissue pedicle, which preserves the blood supply. The sinus is inspected, bony interferences are removed, and the nasal septum is cleared if it impedes movement.

Mobilization

The maxilla is moved into the planned position with full passive mobility confirmed in all directions. Bone is removed from the posterior maxilla, nasal septum, or sinus walls as needed for the planned movement. For impaction, a strip of bone is removed from the lateral wall corresponding to the amount of vertical reduction.

Positioning and Fixation

The intermediate splint (in two-jaw cases) or final splint is placed and intermaxillary fixation is established. Condyles are confirmed seated in the fossae without distraction. Maxillary position is verified with internal and external reference points. Fixation typically uses four L-shaped or straight miniplates (2.0 mm), with two at the pyriform rim and two at the zygomatic buttress, providing a minimum of four fixation points for stable three-dimensional positioning. Bicortical screws at the zygomatic buttress are an alternative. Bone grafts are placed if downgrafting (interpositional grafts maintain vertical height and prevent relapse).

Closure

An alar base cinch suture passes transnasally through the periosteum at the alar base bilaterally to prevent alar widening. V-Y closure advances the midline upper lip mucosa to prevent thinning of the upper lip and blunting of Cupid's bow. The circumvestibular incision is closed in a watertight fashion with resorbable sutures. The throat pack is removed and the oropharynx is suctioned.

<image>Step-by-step surgical illustration of the Le Fort I osteotomy showing: (A) the circumvestibular incision and subperiosteal dissection, (B) the horizontal lateral wall osteotomy from pyriform rim to pterygomaxillary junction, (C) the down-fracture with Rowe forceps, and (D) rigid fixation with four miniplates at the pyriform and zygomatic buttress positions</image>

Segmental Le Fort I Osteotomy

Indications

Segmental Le Fort I osteotomy is indicated for transverse maxillary deficiency requiring expansion beyond what orthodontics can achieve, anterior open bite closure (posterior impaction with segmental movements), and correction of significant curve of Spee or cant in specific segments.

Technique

The standard Le Fort I osteotomy is augmented with interdental vertical osteotomy cuts (parasagittal). A two-piece osteotomy uses a midline split (single interdental cut between the central incisors). A three-piece osteotomy uses two interdental cuts, typically between the laterals and canines bilaterally. A palatal osteotomy connects the vertical cuts through the palatal bone. Each segment can be independently repositioned. Careful protection of dental roots and descending palatine vessels is essential.

Specific Movements

Advancement

Maxillary advancement moves the maxilla anteriorly and is common in Class III and cleft patients. Bone grafting of lateral wall gaps may be required. The alar base cinch suture is essential because advancement widens the alar base. Some nasal tip elevation is expected, and V-Y closure helps mitigate this.

Impaction (Superior Repositioning)

Impaction is the most stable maxillary movement, involving bone-to-bone contact superiorly. It is indicated for vertical maxillary excess (gummy smile, long face). A strip of lateral wall bone equal to the planned impaction is removed. The septum and inferior turbinates must be reduced if they impede impaction. Autorotation of the mandible closes the bite, which may eliminate the need for mandibular surgery in some Class II patients.

Downgrafting (Inferior Repositioning)

Downgrafting is the least stable movement and requires interpositional bone grafts. It is indicated for short face or maxillary vertical deficiency. Graft materials include autogenous bone (iliac crest, cranium), allograft, and xenograft. Without rigid fixation and grafting, the relapse rate is higher.

Cant Correction

Cant correction involves differential vertical movement -- impaction on one side with downgraft or maintenance on the other. It is best assessed clinically rather than on lateral cephalogram and requires PA cephalogram or 3D imaging. VSP is particularly valuable for asymmetric movements.

Complications

Hemorrhage

Estimated blood loss is typically 200-500 mL but can be significantly more. Sources include the pterygoid venous plexus, internal maxillary artery (especially the descending palatine branch), and the posterior superior alveolar artery. The descending palatine artery is the most commonly injured vessel, typically during the posterior osteotomy or down-fracture. Management includes pressure, electrocautery, packing, and clip ligation, with embolization rarely required. Hypotensive anesthesia (MAP 55-65 mmHg) reduces blood loss.

Unfavorable Fracture (Bad Split)

Pterygoid plate fracture extending to the skull base is rare but dangerous, potentially causing CSF leak or cranial nerve injury. Tuberosity fracture may devascularize the posterior segment. Prevention centers on controlled osteotome direction during pterygomaxillary disjunction.

Vascular Compromise

Avascular necrosis of the maxilla is rare when the palatal pedicle is preserved. Segmental avascular necrosis in multi-piece Le Fort I can occur if the palatal blood supply is damaged. The greater palatine artery must be preserved in segmental osteotomies.

Velopharyngeal Insufficiency (VPI)

Maxillary advancement greater than 10 mm may cause velopharyngeal insufficiency with hypernasality and nasal regurgitation. Risk is higher in cleft patients with an already compromised velopharyngeal mechanism. Preoperative nasopharyngoscopy is recommended for cleft patients and large advancements.

Relapse

Impaction is the most stable movement (less than 10% relapse). Advancement is relatively stable with rigid fixation (10-20% partial relapse). Downgrafting is the least stable (20-30% relapse), though grafting reduces this. Relapse is mitigated by rigid fixation, interpositional grafts, elimination of bony interferences, and proper splint fabrication.

Other Complications

Tooth devitalization occurs in 2-5% of teeth near osteotomy or interdental cuts. Nasal changes include alar base widening, nasal tip elevation, and septal deviation. Infraorbital nerve paresthesia is usually transient and results from retraction. Infection is rare (less than 2%), and plate or screw infection may require hardware removal. Non-union and malunion are rare with proper fixation. Sinusitis from sinus exposure is usually self-limiting.

<image>Diagram illustrating common complications of Le Fort I osteotomy, including the locations of potential hemorrhage (descending palatine artery, internal maxillary artery), the mechanism of unfavorable pterygoid plate fracture, and the concept of velopharyngeal insufficiency following maxillary advancement</image>

Clinical Pearls

The alar base cinch suture and V-Y closure are not optional -- they significantly improve the nasal and lip aesthetic outcome. During pterygomaxillary disjunction, the osteotome must be directed inferolaterally and never superiorly or medially, as superior misdirection risks skull base injury. Controlled hypotensive anesthesia dramatically reduces intraoperative bleeding and improves visualization. If bleeding occurs during down-fracture, blind packing should be avoided; instead, the maxilla should be fully down-fractured and packed posteriorly with direct visualization. Condylar seating must always be checked before applying fixation, as condylar distraction leads to postoperative anterior open bite. In impaction cases, the nasal septum must be adequately reduced, or septal deviation and nasal obstruction will result. For large advancements (greater than 6 mm), counterclockwise rotation of the occlusal plane should be considered to improve both aesthetics and the airway.

References

• Bell WH, Epker BN. Surgical-orthodontic expansion of the maxilla. Am J Orthod. 1976.
• Epker BN. Modifications in the sagittal osteotomy of the mandible. J Oral Surg. 1977.
• Proffit WR, et al. Long-term stability of maxillary intrusion with and without advancement. Int J Adult Orthodon Orthognath Surg. 1996.
• Buchanan EP, Hyman CH. Le Fort I osteotomy. Semin Plast Surg. 2013.
• Doucet JC, et al. Complications of Le Fort I osteotomy: a systematic review. Int J Oral Maxillofac Surg. 2017.
• Obwegeser HL. Surgical correction of small or retrodisplaced maxillae. Plast Reconstr Surg. 1969.

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