Magnetic resonance imaging assessment of the temporomandibular joint in disk displacement.

Twenty-four patients (48 joints) presenting signs and symptoms of internal derangement of the temporomandibular joint (TMJ) were studied, combinations of coronal and sagittal magnetic resonance imaging (MRI) being used for assessment of the TMJ disk. In the coronal MRI, lateral or medial disk displacement was confirmed in 10/48 joints (20.8%). Disk displacement in a lateral direction was confirmed in six joints, and in a medial direction in four joints, while, in the sagittal images, anterior displacement of the disk without reduction (ADWR) was observed in 20/48 joints (17/24 cases), among which bilateral ADWR were found in three cases. Rotational disk displacements were observed in eight joints, and of these cases six were anterior and lateral disk displacements, while the remaining two were anterior and medial disk displacements. The disks tended to be displaced in a lateral direction in cases of rotational disk displacement.