The effects of immobilization on the rabbit temporomandibular joint.

While the effects of immobilization of joints covered with hyaline cartilage have been widely studied, the effects on the fibrous tissue-covered temporomandibular joint have not been studied as extensively. This study was designed to determine the short-term effects of immobilization on the rabbit temporomandibular joint. Nineteen rabbits were placed in maxillomandibular fixation. The temporomandibular joints were studied histologically after periods of from ten to 28 days. Significant thinning was observed as early as after ten days, as was degeneration of the cartilage. Degeneration became progressively more severe as the duration of the immobilization increased. Reparative events began appearing after 28 days. These findings suggest that although initially immobilization produces destructive changes, the changes may well be reversible.