The effects of mandibular setback surgery on the upper airway and sleep quality in skeletal Class III patients and comparison with control subjects: a pilot study

Abstract

The aim of this study was to determine the effects of mandibular setback surgery exceeding 5 mm on upper airway and sleep quality in skeletal Class III patients, with comparisons to Class I controls. Sixteen individuals per group were selected based on their ANB angle and surgical need. 2D and 3D airway analyses were conducted. Sleep quality was assessed using the Epworth Sleepiness Scale, the STOP-Bang questionnaire, and a sleep study. Following surgery, all of the skeletal Class III malocclusion patients transitioned to a Class I relationship. This transformation was accompanied by a significant reduction in pharyngeal airway space, minimum cross-sectional area (minCSA), and airway volume. Additionally, the mandibular plane to hyoid distance and airway length increased, and the total apnea–hypopnea index (AHI), obstructive AHI, and snoring levels were elevated. Compared to the control group, significant narrowing of the minCSA and reduction in airway volume, especially in the lower segment, were observed. However, no significant change in sleep quality was noted. In conclusion, the altered upper airway anatomy after mandibular setback surgery exceeding 5 mm in skeletal Class III patients was associated with an increase in AHI, but overall sleep quality was not altered compared to Class I subjects.