Magnetic resonance imaging in the evaluation of temporomandibular joint disc displacement--a review of 144 cases.

One hundred and forty four patients underwent magnetic resonance imaging (MRI) for evaluation of suspected internal derangement (ID) of the temporomandibular joint (TMJ). All scans were performed on a state-of-the-art scanner by highly experienced technologists and evaluated by a single Head and Neck/Maxillofacial radiologist. Seventy-nine percent of patients were female and 21% male. Age distribution of the cases was bi-modal with first peak at 20-30 years of age and second peak at 50-60 years of age. Of the 82.5% of cases with disc displacement, 59.5% demonstrated reduction with opening and 40.5% did not reduce. Anterior disc displacement is common (44%) and sideways displacement rare (4%). Antero-lateral displacement was the second commonest type of displacement (29%) probably related to the weakness of the lateral disc attachment.