Abstract: Objective: To investigate whether rhythmic masticatory muscle activity (RMMA) is associated with sleep micro-arousals (MA), and analyze the association between RMMA of sleep bruxism patients(RMMA/SB) and autonomic cardiac activity. Methods: Thirty SB subjects and thirty control subjects for two consecutive nights were performed by polygraphic recordings. MA index and RMMA index were scored. The mean heart rate from a series of 10 cardiac cycles was calculated at 60, 40, 20 and 5 sec before RMMA onset respectively. To assess a transient beat-to-beat heart rate change in relation to the RMMA onset, heart rate from 5 cardiac cycles before and 5 cycles after the onset were also calculated. Results: Sleep bruxism(SB) subjects showed a higher incidence of rhythmic masticatory muscle activity (RMMA) than control subjects (6.10±1.05 vs. 1.81±0.39, P<0.0001). However, no difference was found in according to their micro-arousal index（7.72±1.21 vs.7.53±1.33, P=0.5641). RMMA/SB was associated with sleep micro-arousals. In both groups, transient heart rate acceleration was observed in relation to the onset of RMMA episodes. Conclusion: RMMA is associated with sleep micro-arousals. In SB subjects, a clear increase in sympathetic activity precedes SB onset.

Key words:  , sleep bruxism, heart rate variability, micro-arousals, sleep cycles

摘要： 目的: 研究夜磨牙(sleep bruxism ,SB)患者睡眠期咀嚼肌节律性运动（RMMA)发生的微觉醒机制。方法:对30名夜磨牙患者、30名正常人进行连续2夜的多导睡眠监测， 研究RMMA事件与微觉醒（MA）的时间相关性；比较2组间RMMA指数及MA指数的差异；RMMA事件发生前60 s、前40 s、前20 s、前5 s，共5个时间点的各连续10个心动周期的平均心率，以及RMMA事件发生前后各5个心动周期的心率变化。结果: 夜磨牙症患者微觉醒指数（7.72±1.21）与正常对照相似(7.53±1.33, P=0.5641)；但咀嚼肌节律性运动频率，即磨牙指数[(6.10±1.05)次/h]约3倍于正常对照组[(1.81±0.39)次/h, P<0.0001)]。 RMMA事件与MA存在高度时间相关性。夜磨牙患者RMMA事件发生前1个心动周期开始心率明显加快。 结论: 夜磨牙患者较正常人群有较高的RMMA频率， RMMA与睡眠微觉醒相关，磨牙事件发生时伴随明显的心脏交感神经活动增加。

关键词:  , 夜磨牙；心率变化；微觉醒；睡眠周期

CLC Number: 

• R787.2