中国实用口腔科杂志

中国实用口腔科杂志 ›› 2010, Vol. 3 ›› Issue (11): 680-682.

• 论著 • 上一篇    下一篇

嚼肌肌电信号的最大Lyapunov指数分析

  

  1. 1. 3M中国有限公司， 广州  510663；2. 中山大学光华口腔医学院·附属口腔医院修复科，广州  510060；3. 南方医科大学生物医学工程学院， 广州  510515
  • 收稿日期:2010-08-30 修回日期:2010-10-25 出版日期:2010-11-15 发布日期:2010-12-10

  • Received:2010-08-30 Revised:2010-10-25 Online:2010-11-15 Published:2010-12-10

摘要：

目的    计算嚼肌在牙尖交错位（ICP）紧咬时表面肌电的最大Lyapunov指数，引入一个新的量化指标，分析咀嚼系统肌电信号的混沌特征。方法    于2009年5—7月在中山大学医学院在校学生中选取20名口颌系统基本正常的个体，其中男、女各10名。在ICP位紧咬时采集其左、右嚼肌的表面肌电，利用小数据量法计算嚼肌肌电信号的最大Lyapunov指数，并进行统计学分析。结果    男性个体左、右两侧嚼肌最大Lyapunov指数分别为17.882±1.7498和18.244±1.3028，女性为14.839±1.8198和14.866±1.3947。 对数据进行两因素析因设计的方差分析，性别差异具有统计学意义，女性的最大Lyapunov指数小于男性（F = 41.158，P＜0.001）；左、右侧部位差异无统计学意义（F = 0.151，P = 0.700）。结论    嚼肌在ICP位紧咬时表面肌电具有混沌特征，适合用非线性动力学方法进行分析。

关键词: 嚼肌, 表面肌电, 最大Lyapunov指数, 混沌

Abstract:

Objective    To calculate the largest Lyapunov exponents of the surface electromyography （EMG） signal of the masseter in the position of the ICP， and analyze the chaos character of the surface EMG of the muscles of mastication system. Methods    Ten male and 10 female young volunteers were involved in this study； the signals of surface EMG of bilateral masseter in the position of ICP were collected；the largest Lyapunov exponents of the EMG signal were calculated using a method from small data sets. Results    The signal of the surface EMG of the masseters were analyzed with nonlinear dynamics methods；the bilateral means of largest Lyapunov exponents of male were 17.882±1.7498 and 18.244±1.3028， while the exponents of female were 14.839±1.8198 and 14.866±1.3947. The data were processed with reusable two-factor analysis of variance，and the results indicated that the factor of gender had effects on the exponents（F = 41.158，P＜0.001）， which meant the largest Lyapunov exponents of male were larger than those of female， and the factor of side of left or right had no effects on the exponents（F = 41.158，P < 0.001）， indicating there was no statistic difference in the largest Lyapunov exponents between right side and left side. Conclusion    The signal of surface EMG of the masseter in the position of the ICP has the character of chaos； the methods of nonlinear dynamics are helpful to analyze the EMG signals of mastication system.

Key words: masseter；surface EMG； largest Lyapunov exponent；chaos