A Study on the Mechanism of the Neck Muscle Pain originated from Occlusal Disharmony.

有咬合干扰的颞下颌关节患者常主诉不仅有咀嚼肌疼痛，还有颈部肌肉疼痛。关于颈部肌肉疼痛的治疗和病因机制，目前仍有一些不明确的问题。因此，我们对胸锁乳突肌（SCM：最大的颈部外侧肌肉）的疼痛进行了一些研究。因此，我们取得了显著的成就。所获得的结果概要将在下面加以说明。为TMJ患者的治疗提供指导。本文报道了颞下颌关节伴SCM疼痛的临床病例，采用正确的前路引导重建治疗。明确了SCM在咬合功能中的作用。SCM的疼痛主要发生在肌肉的插入部分（SCM- i），而不是肌肉的中间部分（SCM- m）。因此，我们通过解剖和肌电图实验来研究上颌一号和上颌一号在咬合功能中的功能差异。通过解剖观察，证实了SCM腹部数量在个体间存在一定差异。通过肌电图分析，发现sc - 1与sc - m的肌电图存在定性和定量上的差异。scm -1的肌电功率谱具有低频带峰（12-13 Hz）。这一峰值表明，在咬合过程中，scm - 1的活动可以通过肌肉的拉伸反射来调节。另一方面，sm - m的肌电图具有更高的频带。scm - 1肌电功率值比SCM-M肌电功率值随咬合力的增大成比例增大。这些结果表明，SCM- i在咬合功能中是活跃的，而SCM在咬合功能中似乎具有插入和中间部分的功能分化。

TMJ patients with occlusal interferences often complain of pains not only in masticatory muscles but also in neck muscles. There are still unclarified points regarding the treatment and the causative mechanism of the pain in neck muscles. Therefore we made some studies focused on the pain in the Sternocleidomastoid Muscle ( SCM : the largest lateral neck muscle). As a result, we have made a remarkable achievements.The outline of the results obtained will be described below.1. We gave a guidance for the treatment of TMJ patients.W had trported on clinical cases of TMJ patients with pain in SCM treated errectively by the reconstruction of proper anterior guidance.2. We clarified the function of SCM during occlusal functions.The pain in SCM occurs mainly in the insertion of the muscle (SCM-I) reather than in the middle part of the muscle (SCM-M). Therefore we made anatomical and electromyographical experiments to investigate the functional differentiation between the SCM-I and the SCM-M during occlusal functions.From the anatomical observation, it was confirmed there are some variations between individuals in the number of belly of SCM. From the electromyographic analysis, it was revealed there are qualitative and guantitative differences between the EMG of SCM-I and that of SCM-M. The powerspectrum of the EMG from the SCM-I had low frequency band with a peak(12-13 Hz).This peak shows that the activity of the SCM-I during occlusal function can be regulated by stretch reflex of the muscle. On the other hand the EMG from the SCM-M bad higher frequency band. The power value of EMG of SCM-I was more increased than that of SCM-M in proportion to the increase of occlusal force. From these results,it reveals that SCM-I is active during occlusal functions and SCM seems to have a functional differentiation between insertion and middle part during occlusal function.