[The study on the relationship between the malocclusion of the third molar and craniomandibular dysfunction]

A total of 33 craniomandibular dysfunction (CMD) patients with third molar malocclusion were studied for their occlusion, condyle position, the TMJ arthrograph and EMG of upper and lower lateral pterygoid muscle (Lpt). The results showed that the condyle displacement was related to the malocclusion of third molar, of which it may induce TMJ click as the result of loss of disccondyle harmonious relationship. Most of the patients showed the abnormal EMG of Lpt. Among which some click TMJ showed no obvious condyle displacement while on the others felt severe pain without TMJ click. It can be considered that both the malocclusion of third molar and dysfunction of Lpt may be the cause of TMJ click.