Abstract: PURPOSE:Using X-ray cephalometrics to analyze the alteration of adult patients' oropharyngeal airway with mandibular prognathism after bilateral sagittal split ramus osteotomy, in order to provide some essentials for treatment and prevention of recurrence. METHODS: Twenty adult patients with mandibular prognathism underwent mandibular setback by way of sagittal split ramus osteotomy. Lateral cephalometrics X-ray films were taken 1 week before treatment, 1 week and 6 months after treatment. The data was collected and analyzed using SPSS 17.0 software package. RESULTS: The patients with skeletal mandibular prognathism underwent orthognathic surgery successfully. The length of soft palate increased and the space of oropharyngeal airway reduced significantly 1 week after surgery (P<0.05); six months after surgery, the length of soft palate reduced and the space of oropharyngeal airway increased significantly (P<0.05). There was no significant difference in the length of soft palate and space of oropharyngeal airway between 1 week before operation and 6 months after operation. CONCLUSIONS: Bilateral sagittal split ramus osteotomy reduced the oropharyngeal airway of patients with skeletal mandibular prognathism significantly in short time, which may cause sleep apnea syndrome. But after a period of adaptation and tissue remodeling, the patients' oropharyngeal airways are inclined to return to the original position.

Key words: Supported, by, Science, and, Technology, Planning, Project, of, Liaoning, Province, (2013021005), and, Science, and, Technology, Planning, Project, of, Shenyang, City, (F11-262-9-42).