Studies on effect of physical therapies and occlusal splints on temporomandibular disorders using blood flow analyses of masseter muscles

本研究的目的是从血流状态的角度阐明物理治疗和咬合夹板对颞下颌疾病（TMD）患者的肌肉疲劳是否有效。方法采用3波长近红外光谱法测定咬肌血流，血流参数为总血红蛋白体积（THb）、氧合血红蛋白体积（OXHb）、脱氧血红蛋白体积（deOXHb）、氧饱和度（StO2）。物理治疗的对象为无咀嚼系统肌肉疼痛史的健康受试者，夹板治疗的对象为有咀嚼肌肉症状的TMD患者，使用稳定夹板。物理治疗为20分钟热敷和30分钟肌电监护。<结果与讨论>1)热敷后THb、OXHb和StO2显著大于静息时。热敷前后deOXHb值无显著差异。结果表明，热敷可以影响咬肌的血流量状态，热敷的效果是增加局部血容量，为有氧能量代谢创造有利条件。2)应用肌动监护仪前后各血流量参数均无显著差异。3)静息时，有夹板的StO2平均值明显大于无夹板的StO2平均值。在咬合期间和咬合后，有夹板的THb明显大于无夹板的THb。结果表明，短期内佩戴稳定夹板会影响咬肌的血流量。然而，长期使用夹板的效果尚不清楚。佩戴夹板后咀嚼肌血流量的纵向变化有待进一步研究。

The purpose of this study was to clarify whether physical therapies and occlusal splints are effective against muscle fatigue of temporomandibular disorders (TMD) patients from the point of view of blood flow state.<Methods>Blood flow of masseter muscles were measured using 3-wave-length near-infrared spectroscopy, and the blood flow parameters were total hemoglobin volume (THb), oxygenated hemoglobin volume (OXHb), deoxygenated hemoglobin volume (deOXHb), and oxygen saturation level (StO2). Subjects for the physical therapies were healthy subjects with no history of muscle pain in the masticatory system, while subjects for the splint therapy were TMD patients with masticatory muscle symptoms who used stabilization splints. The physical therapies applied were 20-minite hot pack and 30-minite myo-monitor.<Results and discussion>1)THb,OXHb and StO2 after the hot pack application were significantly larger than those during resting. The deOXHb showed no significant difference between the values before and after the hot pack application. The results suggest that the blood flow state of human masseter muscles can be influenced by a hot pack, and that the effect of hot pack therapy is to increase regional blood volume and that it creates the advantageous conditions for aerobic energy metabolism.2)There was no no significant difference between the values before and after myo-monitor application in all parameters of blood flow.3)During resting, mean values of StO2 with the splint were significantly larger than those without the splint During and after clenching, THb with the splint was significantly larger than that without the splint. The results suggest that the blood flow of masseter muscles can be influenced by wearing stabilization splints in the short term. However, effect of longtime using of splints is still unknown. Further studies on longitudinal change in blood flow stale of masticatory muscles in wearing splints are needed.