A model for internal derangement and osteoarthritis of the temporomandibular joint with experimental traction of the mandibular ramus in rabbit

OBJECTIVES: The purpose of this study is to make a model of internal derang ement (ID) and osteoarthritis (OA) by postero-superior displacement of the mandible in the rabbit temporomandibular joint (TMJ). MATERIALS AND METHODS: Sixteen Japanese white rabbits (8 months old) were s ubjected to traction of the mandibular ramus in the postero-superior direct ion unilaterally using elastic force and five rabbits were used as the cont rol, The operations were performed without surgical invasion of the TMJ cap sule. Temporomandibular joint tissue was removed after 4 weeks and Technovi t and paraffin sections with or without decalcification were observed histo logically. RESULTS: In contrast to the control group, it showed anterior disc displace ment, disc deformity, resorption of subchondral bone and osteophyte formati on in the drawing side of the experimental group. Intra-articular fibrous a dhesions were observed in both sides. CONCLUSION: It is concluded that posterosuperior displacement of the mandib le caused ID and OA in the rabbit TMJ. This model may contribute to the und erstanding of the etiology of human temporomadibular disorders (TMD).