The use of a mandibular repositioning device for obstructive sleep apnea.

The objective of this study was to verify the effect of a mandibular repositioning device (MRD) on polysomnographic parameters and on the mean electromyographic activity of the masseter and temporal muscles in individuals with obstructive sleep apnea syndrome (OSAS). This is a prospective cohort study conducted at multidisciplinary OSAS center in a tertiary referral center. Nineteen individuals with mild or moderate OSAS associated with Mallampati 3-4 were treated with an MRD during sleep. The subjects underwent diurnal electromyography (EM) and nocturnal polysomnography (PSG) examinations both prior and after initial treatment (3 months with MRD for PSG and 6 and 12 months of treatment for EM). The examinations performed at different times were compared. Comparison of the initial and final polysomnography examination revealed a significant mean reduction of apnea-hypopnea index (AHI) from 13.8 to 7.8. The successful treatment rate with the MRD was 52.6%, and the improved treatment rate was 68.4%. Patients with lower pre-treatment AHI presented higher rates of cure. There was no statistically significant change in electromyography examination among different times. The MRD reduced the apnea-hypopnea index in individuals with enlarged base of tongue and mild and moderate OSAS without damaging the function of the masseter and temporal muscles as determined by electromyography.