The condyle-fossa relationship in temporomandibular disorders. Considerations on the pathogenetic role of the disc.

AIM: The purpose of this study is to evaluate the condylar position and its variation in patients with temporomandibular joint (TMJ) disorders before and after therapy with occlusal gnathologic devices. METHODS: Twenty-five TMJ of 25 patients with temporomandibular joint disorder were examined by linear measurement of the anterior, posterior and superior joint space between the condyle and glenoid fossa through cephalometric analysis on X-ray tomography of the TMJ and by calculating the condylar position with the Pullinger and Hollender method. RESULTS: The average condylar position in the TMJ with DTM was posterior with a mean value of 22.2% and a range from 14.3% to 36%. The condylar position of 25 TMJs was: anterior 0(0%); centric 8(32%) and posterior 17(68%). After therapy with occlusal gnathologic devices the average condylar position was centric with a mean value of 0.6% and a range from 5.3% to 6.6%. The condylar position of 25 TMJs was: anterior 2(8%); centric 22(88%) and posterior 1 (14%). CONCLUSIONS: The hypothesis can be advanced that joint pathology is the consequence of the alteration of the condyle position and therefore of the mandibular movement and vice versa. Therapy with occlusal devices makes it possible to modify the condylar position by increasing the condylar capability to recapture the joint disc.