Healing following conventional and cryosurgical discoplasty in the monkey temporomandibular joint.

The techniques of conventional discoplasty and the scar producing potential of cryosurgical treatment of the bilaminar region were examined in a study of 17 adult female cynomologous monkeys. Temporomandibular joint (TMJ) tissues were obtained at four and 10 days, four, 20, 52, and 78 weeks after surgery, and compared to TMJ tissues in unoperated control animals. No clinically observable changes in weight, occlusion, or jaw function were identified. All the surgical sites healed normally. At necropsy, lesions of the articular surface of the condyle were apparent in areas that had been surgically "shaved." The anterior, intermediate, and posterior zones of the surgically-treated discs were generally free of change. Two cryosurgically-treated discs showed lesions and perforations. Histologic and autoradiographic observations suggested that the bilaminar area heals quickly with minimal scarring, following both conventional surgical manipulation and cryosurgery. Under the conditions of this experiment the cryosurgical technique was judged not to be superior to the conventional surgical approach.