Chondrogenic effect of the perichondrium graft on the internal derangement and osteoarthritis of the temporomandibular joint of the rabbit.

Internal derangement of the temporomandibular joint is usually defined as the disruption of the condyle and disc relationship. In addition to this description the other elements of the joint including the cartilage surface, synovial fluid, the ligaments and the bony surface itself demonstrate varying degrees of pathology in concordance with the stage of the internal derangement, as well. This study is designed to create an osteoarthritic model in the rabbit temporomandibular joint. A 2×2mm defect was performed on the cartilage surface of the both condyles of each animal (n=30). The osteoarthritic changes were demonstrated by computerised tomography sections. The right joints of the animals constituted the control group and the left, the study group. At the time of the defect generation, a perichondrium graft from the animal's ear was implanted onto the defect in the study group. The control group was left to heal secondarily. The joints of three randomized groups of 10 animals for each were inspected at the 4th, 6th, and 8th weeks. Cartilage regeneration and regression of the osteoarthritic changes were demonstrated in the study group both in the 6th and 8th week groups. However, the control group showed less cartilage regeneration and progression of the osteoarthritic changes in all weeks, with progression with time. The perichondrium graft has demonstrated chondrogenic effect on the condyle and this in turn changed the progression to internal derangement.