Postoperative course after SSRO in mandibular asymmetries with or without MMF

Objective: The aim of this study was to assess the necessity of maxillo-mandibular fixation (MMF) from a viewpoint of postoperative stability to treat mandibular asymmetries. Materials and methods: Twenty-four patients who underwent surgical correction of mandibular asymmetry were analyzed. The surgical procedure in all patients consisted of bilateral sagittal splitting ramus osteotomy (SSRO). The segments were then fixed rigidly with titanium screws. A postoperative MMF was performed in 12 patients within 1 day of the SSRO. The MMF lasted for 1 week. The other 12 patients were free to move their jaw on the day of the surgery and received occlusal guidance with elastics starting from the third postoperative day. Posterior-anterior cephalograms were taken preoperatively, 1 day postoperatively, and at 1, 3, 6, 12, and 24 months after surgery. Skeletal and occlusal stabilities along with postoperative complications were then assessed. Results: Nausea and pharyngeal discomforts were observed very often in both groups. Even without MMF, occlusions were guided to the objective positions by an average of 3.5 days after surgery. Occlusal and skeletal stability was satisfactory in both groups, and there was no correlation between the surgical results and the use of postoperative MMF. Conclusion: MMF is not necessary after rigid fixation SSRO for mandibular asymmetry, considering the risks of airway distress.