Self-repair capability of surgically created incisions in TMJ disc: An experimental study on goats

This study was to investigate whether surgically created incisions in discs at different sizes would heal spontaneously. Thirty mature goats were randomly divided into group A (1 mm), group B (3 mm) and group C (5 mm) according to the length of incision on the discs. Five animals in each group were sacrificed at 3 and 6 months postoperatively. The disc and condyle were evaluated by gross, histological and immunohistochemistry examinations. 1-mm discal incisions healed spontaneously with nearly normal gross and histological appearance at 6 months postoperatively, while 3-mm and 5-mm discal incisions failed to heal. Degenerative changes were observed in the fibrocartilage in both 3-mm and 5-mm incision groups, with a greater extent in the 5-mm group. Our results suggested that the TMJ disc of goat has limited self-repair capability to damage, which will be useful for making pre-surgical decisions related to the size and healing period of TMJ disc perforations.