Changes of the collagen fibre arrangement of the rabbit temporomandibular joint following discectomy

Purpose: The purpose of the present study is to examine changes in arrangement of collagen fibres of the temporomandibular joint (TMJ) following discectomy. Material and Methods: Twelve male Japanese white rabbits were used. The right TMJs of six rabbits were surgically exposed, and the disc removed with a scalpel. Three untreated and three sham-operated rabbits were used as controls. The TMJs were removed in three rabbits 1 month and in three other rabbits, 3 months after discectomy and processed for demonstration of collagen fibres. Results: One month after discectomy, collagen fibres in the fibrous layers of condyle and articular eminence were of various sizes and were running in various directions. Collagen fibres in the cartilaginous layers were sparser in the study TMJs than in the control TMJs. Three months after discectomy, the direction of collagen fibres in the fibrous layers of the condyle and articular eminence became organized and were similar to that in the control TMJs. However, collagen fibres in the cartilaginous layers of the condyle remained sparser 3 months after discectomy than in the control TMJs. Conclusion: Experimental discectomy in the rabbit alters the distribution and density of collagen fibres in the TMJ. Thorough postoperative follow-up seems to be necessary after discectomy.