Temporomandibular joint, also known as temporomandibular joint, his exact location should be in the external auditory canal mouth of the anterior lateral, when touching with a finger, when opening the mouth can be clearly felt to move. The TMJ is usually symmetrical bilaterally, and there is no obvious tenderness when pressed. Some patients may have tenderness after pressing and cause tremor, which is mainly due to the incorrect way of chewing when eating. Generally, it is necessary to chew bilaterally, not with one side of the habitual chewing, so that one side of the joint force, will cause bilateral development imbalance, because of the cause of temporomandibular arthritis, activity is too large, when opening the mouth will cause bilateral asymmetric, produce noise, easy to dislocation of the temporomandibular joints.