磨牙症是由于咀嚼肌产生一种功能性收缩 ,使下颌正常生理休息位中断 ,表现为磨动牙齿或将牙齿咬紧。 1 971年Ｒａｍｆｊｏｒｄ[1 ] 将之定义为“副功能性磨动牙齿” ,并提出紧咬牙和磨动牙齿间是有区别的。紧咬牙称为正中磨牙症 ,磨动牙齿称为非正中磨牙症。磨牙症对人体可产生 Bruxism is due to a functional contraction of the masticatory muscles, so that the normal physiological resting position of the mandible interrupted by the performance of grinding teeth or teeth clenched. 1 In 1971 Ramfjord [1] defined it as “para-functional grinding of the teeth” and suggested that there was a difference between a bite and a grinding tooth. Tightening teeth called the median bruxism, grinding teeth known as non-central bruxism. Bruxism can be produced on the human body