Endoscopically assisted sagittal split osteotomy for mandibular lengthening: technical note and initial experience

Abstract

Objective: To demonstrate the feasibility of carrying out a sagittal split osteotomy with rigid osteosynthesis via a small oral incision, working in two distinct tunnels and one corridor, using a standard 30 degrees 4-mm Ø endoscope. The procedure can be classified as minimally invasive, allowing for ambulatory treatment and return to daily activities within a week.

Material and methods: Thirty-one bilateral procedures were performed on selected patients, all of whom needed mandibular lengthening to obtain a functional occlusion and enhanced facial profile.

Results: Transoral osteosynthesis was performed in all but one patient, in whom a transbuccal approach was required to fix the beginning of a "bad" split. Three screws were placed in each of 50 mandibular sides; two screws were placed in each of 10 sides (six screws along the upper border, and four above and below the mandibular canal). Two sides required additional plate osteosynthesis. In four patients, there was fixation instability, either bilaterally with opening of the bite, or unilaterally with protrusion of the mandible; these instabilities were managed conservatively with intermaxillary elastics. In the cases of mandibular lengthening only, oedema was minimal after one week, allowing patients to return to normal daily activities.

Conclusions: Endoscopically assisted mandibular lengthening with bilateral sagittal split osteotomies and transoral osteosynthesis reduces periosteal degloving and consequent oedema. The minimal surface available for screw osteosynthesis contributes to the difficulty of the procedure.