An experimental study on reconstruction of the condyle of the temporomandibular joint using free autogenous costal perichondrial grafts in rabbits

Objective. The purpose of this study was to develop a new method to regenerate articular cartilage of the temporomandibular joint (TMJ) by transplantation of free autogenous costal perichondrium (PC). Study design. In the study, 50 adult rabbits received the operation. For the surgery in the test group, the rabbits were randomly matched in pairs within the group and underwent the surgery of cross transplantation of costal PC after trimming the articular surface of the condyle. Operations were carried out in the same way in the experimental group except for PC transplantation. Instead, the suture was stitched in stratified order in the control group. Examination methods included observation of sections under the microscope, observation of specimens under the electron microscope, proliferating cell nuclear antigen (PCNA) staining, and biochemical analysis of glucuronic acid (GA) content and collagen content. The results of different groups were compared with ANOVA. Results. The transplanted homologous PC escaped observable immune repulsion so that it could survive to form new joint cartilage with approximately normal tissue structure and biochemical constitution. The reproduction process was similar to the normal one, but was prolonged a little. At the later stage, the degeneration and calcification in the basal layer increased. However, because of its limited scope, no apparent effect on cartilage growth and function was observed. Conclusions. Homologous xenografting of free costal PC will not result in an apparent immunorejection of the host. Instead, the grafts can maintain their existence by obtaining nutrition from surrounding tissues and regenerate cartilage tissue. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: 664-668)