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

有咬合干扰的TMJ患者不仅主诉咀嚼肌疼痛，而且还主诉颈部肌肉疼痛。对于颈部肌肉疼痛的治疗和致病机制，目前仍有一些不清楚的地方。因此，我们对胸锁乳突肌(SCM：颈部最大的外侧肌)的疼痛进行了一些研究。结果，我们取得了令人瞩目的成就。现将所取得的成果概述如下。结论：1.对TMJ患者的治疗进行了指导，报道了TMJ患者伴有颈椎前路疼痛的临床病例，采用正确的前路重建治疗。我们阐明了SCM在咬合功能中的作用，SCM的疼痛主要发生在肌肉止点(SCM-I)，而不是肌肉中部(SCM-M)。因此，我们进行了解剖学和肌电实验，研究了SCM-I和SCM-M在咬合功能过程中的功能分化。从解剖观察证实，SCM的腹数存在个体之间的差异。肌电分析表明，SCM-I和SCM-M的肌电有定性和定量的差异。SCM-I肌电的功率谱有一个峰值(12-13赫兹)的低频段，说明SCM-I在咬合功能过程中的活动受肌肉牵拉反射的调节。另一方面，来自SCM-M的肌电不利于更高的频段。SCM-I的肌电功率值比SCM-M的高，且与咬合力的增加成正比。这些结果表明，SCM-I在咬合功能过程中是活跃的，在咬合功能过程中，SCM似乎在插入部分和中间部分之间存在功能分化。

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.