The Effect of Immobilization on the Healing Process of Experimental Microtrauma of the Articular Disc on the Temporomandibular Joint of Monkeys

Abstract

This study concerns the effect of immobilization on the healing process of the experimental microtrauma of the articular disc on the temporomandibular joint of the monkeys.
Temporomandibular joints were opened surgically and the discs were injured by a special type of knives for microtrauma. Two kinds of microtrauma were produced. One was confined to the articular surface of the disc and the other was beyond the articular surface over the peripheral synovial lining.
The opposite side of the temporomandibular joint operated on was used as control.
Then these mandibles were immobilized by intermaxillary wire fixation from one week to six weeks. In one of these animals, the mandible was remobilized for over nine weeks after six weeks of immobilization.
Sections from the temporomandibular joints showed that no repair was demonstrated in the injured area which mas confined to the articular surface. But in the wound communicating with the peripheral synovial lining, immature mesenchymal cells began to invade along the bottom of the incisive cleavage from the synovial lining to the wound.
Up to six weeks of immobilization, no adhesion to the articular eminence and condylar process in the central portion of the articular disc was observed.