REACTIVE CHANGES IN THE TEMPOROMANDIBULAR-JOINT AFTER MANDIBULAR MIDLINE OSTEODISTRACTION

The purpose of this study was to evaluate the histologic changes withi n the condyle in response to mandibular widening using osteodistractio n. Mandibular midline osteotomies were made in nine Macaca mulatta mon keys and tooth-borne distraction devices were bended to the mandibular dentition, Distraction was continued until a 3-5 mm widening was achi eved. The appliances were then stabilized for a period of 4 weeks. Non -decalcified sagittal sections of the lateral, middle and medial third s of the condyles were analyzed. although three of the seven animals s howed no unusual morphology, four others exhibited morphologic differe nces within the fibrous layer, cartilage layer or bone/cartilage inter face. Histologic changes mere seen to occur in the fibrous layer, cart ilaginous layer and cartilage/bone interface. The severity of these ch anges were correlated with the likely rotational forces directed at th e condyle on the postero-lateral and antero-medial surfaces.