Association of masticatory muscle activity with sleep arousal and other concomitant movements during sleep

OBJECTIVE:
This study aims to verify the associations among sleep bruxism (SB), sleep arousal (SA) and concurrent body movements.
MATERIAL AND METHODS:
Subjects underwent a standard overnight polysomnography test and audio-video recordings. Sleep quality was evaluated according to the Rechtschaffen and Kales criteria, while SA was determined as per the American Sleep Disorders Association criteria. Analyses were performed by an external institution after masking of the subjects' information. SB was assessed based on the presence/absence of rhythmic masticatory muscle activity (RMMA) episodes, which were identified by using electromyography of the masseter muscle. The observed simultaneous movements included lower leg movement (LLM), swallowing, face scratching, head movement, body movement, eye blinking, coughing, licking, sighing, body scratching, lip sucking, somniloquy and yawning. The LLM was determined visually, as well as through an increase in the tibialis electromyogram signal. Other movements were visually assessed using audio-video recordings. The incidences of all the simultaneous movements were compared between RMMA with intercurrent SA (SAwRMMA; RMMA episode derived from a masseter electromyogram showing more than 10% of maximum voluntary contraction) and SA without RMMA (SAw/oRMMA).
RESULTS:
Fourteen subjects were included in this study (females/males: 4/10, mean age: 31.5 ± 5.7 years). Among these, LLM, swallowing, body movement, licking, body scratching and lip sucking were frequently observed in SAwRMMA episodes than in SAw/oRMMA episodes, significantly. However, the non-specific simultaneous movements were higher observed in SAw/oRMMA episodes than that in SAwRMMA.
CONCLUSION:
Our results suggest that SB is concurrently activated with LLM in relation to arousal.

This is the peer reviewed version of the following article: Haruna Miki et. al. Association of masticatory muscle activity with sleep arousal and other concomitant movements during sleep.. Journal of Oral Rehabilitation (2020) 47(3), 281-288, which has been published in final form at https://doi.org/10.1111/joor.12913| This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.