Abstracts—dental radiology vol. 36, 1996

Abstract

Quantitative analysis of the temporomandibular joint(TMJ)motion in patients with craniomandibular joint disorder was performed by means of magnetic resonance (MR) im aging. This study included. 134 patients(37 men and 97 women, mean age 34.0 years)having craniomandibular joint disorders diagnosed clinically and 16 healthy volunteers(14 men and 2 women, mean age 35.0 years). A 1.5 T superconductive MR unit(Signa Advantage, GE), 3-inch bilateral surface coils(as a receiver)and a body coil(as a transmitter)were used with the multiplanar gradient echo technique(MPGR). The obtained sagittal images were displayed in a closed loop cine fashion. The images were then digitized and transferred to a computer workstation (H 2050 G, Hitachi)for analysis of motion using original software. The results obtained were as follows: 1 ) Abnormalities of the disk position were identified in 82% of the patients. However, no malpositions of the disk were identified in 18% of the patients. 2) The cases with anterior disk displacement without reduction were associated with restriction of anterior translation of the condyle, and the motion of the opposite side was abnormal. 3) In the cases with disk displacement with reduction, the condylar paths were of the figure-of-eight shape. 4) The advantage of this analysis is that simultaneous evaluation of bilateral TMJ and accurate evaluation of condylar paths is possible.