Abstract
The aim of this study was to derive the relationship between clinical symptoms and disc configuration on MR images of both sides with TMJ symptoms present or absent in juvenile patients with unilateral symptomatic temporomandibular disorders. The subjects were comprised of a study group of 80 juvenile patients with unilateral TMJ symptomatic temporomandibular disorders. The TMJ assessment consisted of the disc position, disc morphology and disc reduction at the maximum opening position using sagital MR images. Anterior disc displacement (ADD) was observed in 73 (91.3%) out of 80 patients consisting of 40 (50.0%) patients with bilateral ADD,31 (38.8%) patients with unilateral ADD on the side with the symptom and 2 (2.5%) patients with unilateral ADD on the side without the symptom. ADD was observed in 71 (88.8%) out of 80 TMJs on the side with the symptom and 42 (52.5%)out of 80 TMJs on the side without the symptom (p<0.01). Intermediate level of ADD was observed more on the side with the symptom of TMJ,43 (60.6%), than on the side without the symptom,23 (54.8%), (p< 0.05). Disc deformation was observed more on the side with symptom TMJ,44 (55%), than on the side without symptom 27 (33.8%) (p<0.05). ADD without reduction at the maximum opening position was observed more on the side with the symptom 41 (57.7%), than on the side without symptom 13 (31 %), of TMJ. Number of juvenile patients with bilateral ADD seemed to increase with their age. From this study it was clear that the grade of the ADD on the side with the symptom in juvenile patients with unilateral symptomatic disc disorders was worse than that of the ADD on the side without the symptom.
Moreover, these results implied that unilateral ADD may be one of the etiological factors of ADD on the contralateral side because of derangements of bilateral condylar movements.
