Three-dimensional evaluation of the pharyngeal airway using cone-beam computed tomography following bimaxillary orthognathic surgery in skeletal class III patients.

Abstract

The study aims to evaluate the pharyngeal airway space (PAS) following bimaxillary surgery in skeletal class III patients and to compare the changes in PAS between genders using cone-beam computed tomography (CBCT). In all, 38 patients (16 male and 22 female) with skeletal class III malocclusion underwent bimaxillary surgery. CBCT scans were acquired approximately 1month before surgery, 3months after surgery, and 6months after surgery. The oropharyngeal volume and the minimum cross-sectional area (CSA) were characterized using the InVivoDental imaging software package at each time point. The volume and minimum CSA decreased significantly postoperatively, which was maintained until 6months postoperatively (p<0.01). The location of the minimum CSA tended to move into the retropalatal and retroglossal areas postoperatively. A strong correlation between volume and minimum CSA was found. The amount of mandibular setback was not correlated with the change in the airway. By gender, significant decreases in both the volume and minimum CSA were found in females (p<0.05) but not in males. Bimaxillary surgery significantly affects PAS. Gender differences should also be considered when considering changes in PAS. An awareness of the effects of bimaxillary setback surgery on the airway should be considered when implementing an orthognathic treatment plan.