The effects of mandibular advancement appliance therapy on jaw-closing muscle activity during sleep in patients with obstructive sleep apnea: a 3-6 months follow-up

Abstract

Study objectives: The main aim of this study was to investigate the effects of mandibular advancement appliance (MAA) therapy on jaw-closing muscle activity (JCMA) time-related to respiratory arousals, and on JCMA time-related to nonrespiratory arousals in patients with obstructive sleep apnea.

Methods: Eighteen patients with OSA (mean ± standard deviation = 49.4 ± 9.8 years) with a mean ± standard deviation apnea-hypopnea index of 22.0 ± 16.0 events/h of sleep participated in a randomized controlled crossover trial in which two ambulatory polysomnographic recordings, 1 with an MAA in situ and another without the MAA in situ, were performed. JCMA was quantified as the sum of rhythmic masticatory muscle activities and other orofacial activities.

Results: Significant reductions in the apnea-hypopnea index (Z = -2.984; P = .003), in the respiratory arousal index (Z = -2.896; P = .004), and in the JCMA time-related to respiratory arousal index (Z = -3.434; P = .001) were found with MAA in situ. On the nonrespiratory arousal index, and on the JCMA time-related to nonrespiratory arousal index, MAA had no significant effect (T = 2.23; P = .82; and Z = -0.66; P = .51, respectively).

Conclusions: This study shows that effective mandibular advancement appliance therapy significantly reduces jaw-closing muscle activities time-related to respiratory arousals in OSA patients. Future studies are needed to confirm these findings in obstructive sleep apnea patients with comorbid sleep bruxism.

Clinical trial registration: Registry: ClinicalTrials.gov; Name: The Effects of Oral Appliance Therapy on Masseter Muscle Activity in Obstructive Sleep Apnea; Identifier: NCT02011425.

Keywords: mandibular; masticatory muscles; obstructive sleep apnea; oral appliance; sleep bruxism; upper airway.

© 2020 American Academy of Sleep Medicine.

Figures

Figure 1. JCMA time-related to respiratory and nonrespiratory arousals indices.

(A) Individual values of the JCMA time-related to respiratory arousals index without MAA in situ and with MAA in situ (n = 18). There was a significant reduction in the JCMA time-related to respiratory arousal index with MAA in situ (*P = .001). (B) Individual values of JCMA time-related to nonrespiratory arousals index (n = 18). No significant effect was observed of the MAA on the JCMA time-related to nonrespiratory arousals index (P = .507).