Evaluation of the condylar movement on MRI during maximal mouth opening in patients with internal derangement of TMJ; comparison with trans cranial view

악관절 내장증 환자의 최대 개구시 하악과두 운동량에 대한 자기공명영상 평가; 경두개촬영법과의 비교

Purpose: To evaluate the condylar movement at maximal mouth opening on MRI in patients with internal derangement. Materials and Methods: MR images and transcranial views for 102 TMJ s in 51 patients were taken in closed and maximal opening positions, and the amount of condylar movement was analyzed quantitatively and qualitatively. Results: For MR images, the mean condylar movements were 9.4 mm horizontally, 4.6 mm vertically and 10.9 mm totally, while those for transcranial views were 12.5 mm, 4.6 mm, and 13.7 mm respectively. The condyle moved forward beyond the summit of the articular eminence in 41 TMJs (40.2%) for MR images and 56 TMJs (54.9%) for transcranial views. Conclusion: The horizontal and total condylar movements were smaller in MR images than in transcranial views.