单侧后牙缺失对咀嚼肌肌电图的影响

目的:观察单侧后牙缺失对咀嚼肌肌电图的影响,从而探讨单侧后牙缺失在颞下颌关节(temporomandibular joint, TMJ)发病中的作用。方法:对40例单侧上颌后牙缺失患者组成的缺牙组和40例牙列完整的自愿者组成的对照组,进行肌电图检查。结果:缺牙组无论是松弛状态或紧咬时咀嚼肌的电位明显高于对照组(P<0.05),并且缺牙组紧咬时同名肌不对称性活动增加(P<0.05),其中对照组的咬肌肌电活动的对称性明显高于缺牙组(P<0.01),以上变化缺牙侧较非缺牙侧显著(P<0.05)。结论:单侧后牙缺失可以对咀嚼肌肌电图造成影响,可能是颞下颌关节疾病的发病原因之一。

The influence of unilateral posterior teeth loss on the electromyography of masticatory muscles

Objective: To investigate the influence of unilateral posterior teeth loss on the electromyography ofmasticatory muscles and to explore the role of unilateral posterior teeth loss in the etiology of temporomandibular diseases.Methods: The electromyography of masticatory muscles was studied in 40 patients with unilateral posterior teeth loss and40 volunteers with complete dentition as control. Results: The EMG activity of masticatory muscles was higher duringclenching or relaxation condition in patient group than in the control group (P<0.05). Asymmetry activity of homonymousmuscles increased during clenching in the patient group. The symmetry of EMG activity in masseter muscle was higher inthe control group than in the patient group (P<0.01). Conclusion: Unilateral posterior teeth loss has effect on theelectromyography of masticatory muscles and may play a role in temporomandibular diseases.