Shiraishi Yuki, Tachibana Masaya, Shirota Ai, Mohri Ikuko, Taniike Masako, Yamashiro Takashi, Kato Takafumi
Department of Orthodontics and Dentofacial Orthopedics, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan.
Department of Oral Physiology, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan.
Sleep. 2021 Nov 12;44(11). doi: 10.1093/sleep/zsab156.
The present study aimed to clarify the physiological relationships between rhythmic masticatory muscle activity (RMMA) and cyclic changes in cortical, autonomic, and arousal-motor activities during sleep in sleep bruxism (SB) children.
Polysomnographic recordings were performed on 15 SB children (9 boys, 6 girls, 10.3 ± 2.5 years) and 18 control children (5 boys, 13 girls, 10.7 ± 3.1 years) free from sleep and developmental disorders. Sleep and RMMA were scored by the standard rules. Sleep cycle was divided into NREM and REM sleep segments and the frequency of RMMA, transient arousal and movement, and cortical and cardiac activities were then quantitatively analyzed in relation to sleep cycles.
Neither sleep architecture nor sleep stage distribution of RMMA significantly differed between the two groups. In sleep cycles, SB children showed more frequent RMMA in all segments than controls, while cyclic changes in cortical and autonomic activities did not significantly differ between the two groups. In SB children, RMMA was the most frequent in the last NREM segment before REM sleep and was associated with increases in cortical beta activity and arousal; more than 70% of RMMA time-dependently occurred with cortical and motor arousals.
This is the first study to suggest that the potentiation of RMMA occurrence was associated with transient arousal under cyclic sleep processes in primary SB children.
本研究旨在阐明睡眠磨牙症（SB）儿童睡眠期间节律性咀嚼肌活动（RMMA）与皮质、自主神经及觉醒运动活动的周期性变化之间的生理关系。
对15名SB儿童（9名男孩，6名女孩，10.3±2.5岁）和18名无睡眠及发育障碍的对照儿童（5名男孩，13名女孩，10.7±3.1岁）进行多导睡眠图记录。按照标准规则对睡眠和RMMA进行评分。将睡眠周期分为非快速眼动（NREM）和快速眼动（REM）睡眠阶段，然后定量分析RMMA、短暂觉醒和运动以及皮质和心脏活动的频率与睡眠周期的关系。
两组之间的睡眠结构和RMMA的睡眠阶段分布均无显著差异。在睡眠周期中，SB儿童在所有阶段的RMMA均比对照组更频繁，而两组之间皮质和自主神经活动的周期性变化无显著差异。在SB儿童中，RMMA在REM睡眠前的最后一个NREM阶段最为频繁，且与皮质β活动增加和觉醒有关；超过70%的RMMA随时间与皮质和运动觉醒同时出现。
这是第一项表明原发性SB儿童在周期性睡眠过程中RMMA发生增强与短暂觉醒相关的研究。
