Effect of Maxillomandibular Advancement Surgery on Pharyngeal Airway Volume and Polysomnography Data in Obstructive Sleep Apnea Patients

Abstract

To study volumetric changes in the upper airway in patients with obstructive sleep apnea (OSA) after maxillomandibular advancement (MMA) and compare those findings with polysomnographic (PSG) data of the same patients. The study included 20 patients with OSA (1 woman and 19 men; mean age, 48yr; range, 31 to 59yr). Mean values of angles formed by the sella, nasion, and B point and the sella, nasion, and A point before surgery indicated mandibular and maxillary retrognathia, respectively. All patients were treated with MMA and pre- and postoperative orthodontics. Pre- and post-treatment cone-beam computed tomograms were used to measure upper airway volume and PSG data were used to examine the apnea-hypopnea index (AHI) and oxygen desaturation index (ODI-3 or ODI-4). In addition, Epworth Sleepiness Scale (ESS) score, General Health Questionnaire (GHQ-12) score, and amount of MMA were collected from patients' files. Mean maxillary and mandibular advancement was 4.6±1.9 and 9.3±1.7mm, respectively. A statistically relevant increase (mean, 64.1%) in airway volume was found, with large individual variation. ODI-3 or ODI-4 and AHI values showed statistically relevant improvements from before to after surgery. ODI-3 or ODI-4 score decreased from 12.3±9.8 to 4.0±4.2 and AHI score decreased from 21.4±13.8 to 5.8±7.2. ESS scores showed improvement (lower scores) after surgery for most patients (n=15), whereas GHQ-12 scores showed improvement (lower scores) for only 6 patients. MMA increases upper airway volume and lessens OSA symptoms according to PSG data. MMA can be considered curative treatment for OSA; however, residual apnea as measured by the AHI can be found in many patients.