Objective
The objective was to characterize the contralateral non‐surgical temporomandibular joint (TMJ) in mice that had an opposing osteoarthrosis(OA)‐like joint induced by unilateral partial discectomy.
Methods
TMJs on one side in mice were subjected to partial discectomy. Both surgical and contralateral non‐surgical TMJs were collected at 4, 8, 12 and 16 weeks post‐surgery for histological examination. The morphology of the articular cartilage of the condyle was evaluated using a scoring system.
Results
A progression of articular cartilage degeneration was seen in the TMJs following unilateral partial discectomy, including increased proteoglycan staining in the extracellular matrix at 4 weeks, the appearance of chondrocyte clusters at 8 weeks, reduced proteoglycan staining and fibrillation at 12 weeks and the loss of articular cartilage at 16 weeks. In the contralateral non‐surgical TMJs, increased proteoglycan staining occurred in the articular cartilage of the condyle at 8 weeks and continued to age.
Conclusion
The result indicated that OA‐like changes in one TMJ by partial discectomy could initiate early‐onset articular cartilage degeneration in the contralateral non‐surgical TMJ in mice.