Articular disk displacement of TMJ due to trauma.

One hundred and thirty native American Indian patients undergoing orthodontic treatment for malocclusions were screened for temporomandibular joint (TMJ) abnormalities. These patients were followed over the course of orthodontic treatment and six of these patients suffered a traumatic injury to the TMJ. These six patients who had been previously screened and found to be asymptomatic, developed symptoms. Three were diagnosed with articular disk displacement of the TMJ confirmed by magnetic resonance imaging (MRI).