Pharyngeal airway space changes after counterclockwise rotation of the maxillomandibular complex.

Abstract

The purpose of this study was to evaluate the effects of double-jaw surgery with counterclockwise rotation of the maxillomandibular complex on the pharyngeal airway space and velopharyngeal anatomy in patients with high occlusal plane facial morphology. Fifty patients (22 men, 28 women) with high occlusal plane facial morphology underwent double-jaw surgery with counterclockwise rotation of the maxillomandibular complex. The patients were divided into 2 groups: group 1, 30 patients (8 men, 22 women) who underwent maxillary and mandibular advancement and group 2, 20 patients (14 men, 6 women) who underwent maxillary advancement and mandibular setback. Presurgery and postsurgery lateral cephalometric radiographs were analyzed to correlate changes in pharyngeal airway space dimensions and velopharyngeal anatomy with maxillary and mandibular positional changes. The calibration showed a more than 0.94 correlation for both intra- and interoperator error. The average follow-up time was 29.6 months in group 1 and 22.2 months in group 2. Mean maxillary surgical change at point A was 4.15 mm in group 1 and 2.5 mm in group 2. Mean mandibular surgical change at the genial tubercles was 7.5 mm in group 1 and -4.95 mm in group 2. After surgery, group 1 patients had an increase in pharyngeal airway space of 47% at the soft palate and 76% at the base of the tongue relative to the amount of mandibular advancement. Group 2 patients had a decrease in pharyngeal airway space of 47% at the soft palate and 65% at the base of the tongue relative to the amount of mandibular setback. Double-jaw surgery with counterclockwise rotation of the maxillomandibular complex significantly affects the pharyngeal airway space and velopharyngeal anatomy in patients with high occlusal plane facial morphology, with both mandibular advancement and setback.