Department of Temporomandibular Disorders, Center for Advanced Oral Medicine, Hokkaido University Hospital, Sapporo, Japan.
Department of Crown and Bridge Prosthodontics, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan.
J Prosthodont Res. 2024 Jan 16;68(1):92-99. doi: 10.2186/jpr.JPR_D_22_00231. Epub 2023 Mar 31.
Purpose This study aimed to measure masseter muscle activity throughout the day in outpatients suspected of having awake bruxism (AB) and/or sleep bruxism (SB) and examine the relationship between AB and SB by comparing muscle activity during daytime wakefulness and nighttime sleep.Methods Fifty outpatients with suspected SB and/or AB participated in this study. A single-channel wearable electromyogram (EMG) device was used for EMG recording. The selected EMG bursts were divided into bursts during sleep (S-bursts) and bursts during awake state (A-bursts). The number of bursts per hour, average burst duration, and ratio of burst peak value to maximum voluntary contraction were calculated for both the S- and A-bursts. These values of the S- and A-bursts were then compared, and the correlations between them were analyzed. Additionally, the ratios of phasic and tonic bursts in the S- and A-bursts were compared.Results The number of bursts per hour was significantly higher for A-bursts than for S-bursts. No significant correlation was found between the numbers of S- and A-bursts. The ratio of phasic bursts was large and that of tonic bursts was small in both the S- and A-bursts. A comparison of the S- and A-bursts showed that the S-bursts had a significantly lower ratio of phasic bursts and higher ratio of tonic bursts than the A-bursts.Conclusions The number of masseteric EMG bursts during wakefulness did not show any association with that during sleep. It became clear that sustained muscle activity was not dominant in AB.
本研究旨在测量日间门诊疑似觉醒磨牙症（AB）和/或睡眠磨牙症（SB）患者的咀嚼肌活动，并通过比较日间清醒状态和夜间睡眠期间的肌肉活动，来研究 AB 和 SB 之间的关系。
本研究纳入了 50 名疑似 SB 和/或 AB 的门诊患者。使用单通道可穿戴肌电图（EMG）设备进行 EMG 记录。选择的 EMG 爆发被分为睡眠期间的爆发（S-爆发）和觉醒状态期间的爆发（A-爆发）。计算了每小时爆发次数、平均爆发持续时间和爆发峰值与最大自主收缩的比值，用于 S-和 A-爆发。然后比较 S-和 A-爆发的这些值，并分析它们之间的相关性。此外，还比较了 S-和 A-爆发中相性和紧张性爆发的比值。
A-爆发的每小时爆发次数明显高于 S-爆发。S-和 A-爆发的数量之间没有发现显著相关性。S-和 A-爆发中相性爆发的比例较大，紧张性爆发的比例较小。S-和 A-爆发的比较表明，S-爆发的相性爆发比例明显低于 A-爆发，紧张性爆发比例明显高于 A-爆发。
觉醒状态下咀嚼肌 EMG 爆发的次数与睡眠期间没有任何关联。这表明在 AB 中，持续的肌肉活动并不占主导地位。
