TMJ Disc and Condylar Displacement in the Frontal Plane

It is known from the literature that an anterior disc displacement is as a rule associated with a dorsal and (or) superior condylar displacement, whereas a dorsal disc displacement is connected with an anterior displacement of the condyle in the intercuspal position. No investigations have been done on this subject in the frontal plane. MR investigations of the TMJs were carried out in 38 patients. Disc displacement in the frontal plane was analysed in 72 TMJs. In 47.2% it was associated with condylar displacement in this plane. In 55.5% medial disc displacement was connected with lateral condylar displacement, whereas lateral disc displacement was accompanied by medial displacement of the condyle (p>0.05) in 33.3%. Central position of the condyles was significantly more often (66.6%) noted in TMJs with lateral disc displacement than in TMJs with medial disc displacement (44.4%) (p>0.05). These results were confirmed by tomography in 40 TMJs. CONCLUSION: There is a correlation between disc and condylar displacement in the intercuspal position, not only in the sagittal but also in the frontal plane. To avoid a mistake in the establishment of maxillo-mandibular relationship both the condylar and the disc position should be taken into consideration. Grant of the State Committee for Scientific Research nr 6 PO5E 043 20