The long-term results of modified maxillomandibular advancement in Asian OSA patients

Maxillomandibular advancement (MMA) surgery is considered a highly successful treatment for obstructive sleep apnea (OSA). Various modifications to the technique have been described. We aim to study the long-term results in Asian patients who underwent a modified MMA procedure intended to avoid bimaxillary protrusion and which involved four-quadrant bicuspid extractions with posterior maxillary alveolar setback.

A review of operative logs from 2000 to 2003 was conducted to identify Asian patients who underwent modified MMA during that period, for treatment of moderate and severe OSA. Sleep indices and psychometric performances were prospectively analyzed.

Eight Asian patients were included. The mean length of follow-up was 14.4 years (range: 13.0-16.5). Mean preoperative apnea-hypopnea index (AHI) was 48.9 (range: 19.0 to 84.8). Mean post-operative AHI was 31.6 (range: 6.2 to 79.5). This reduction was statistically significant (p<0.05). Epworth Sleepiness Scale and Functional Outcomes of Sleep Questionnaire (FOSQ) revealed that majority of the patients (75%) did not have excessive daytime somnolence and all patients had high FOSQ totalled scores (mean 17.7, range 11.8 to 20), indicating good functional performance.

This series is the longest follow-up of an Asian cohort who underwent modified MMA. With a mean follow-up of 14.4 years, improvement in AHI is still observed but not at a degree as large as prior studies with shorter lengths of follow-up. The purported efficacy of MMA for Caucasian patients may not be reproducible in Asian patients and long-term sustainability of this treatment's efficacy requires rigorous evaluation.