MMP-3 and -8 expression is found in the condylar surface of temporomandibular joints with internal derangement.

Background: Internal derangement is one of the most common disorder of the temporomandibular joint (TMJ). The aim of this study was to investigate the associations of matrix metalloproteinase (MMP)-3 and -8 expression in articular condylar surface with different stages of TMJ internal derangement according to Wilkes (Minn Med, 1978; 61: 645-52) and osteoarthrosis (OA) according to Dijkgraaf et al. (J Oral Maxillofac Surg, 1995; 53: 1182-92).

Methods: The study was based on 54 condylar specimens obtained during TMJ surgery. Immunohistochemistry using antibodies specific to MMP-3 and -8, represented in cartilage destruction, was carried out.

Results: In all tissue specimens, MMP-3 expression was intense in the surface layer but showed less intensive staining in the deeper layers. Some MMP-8 expression was also seen. The severity of TMJ internal derangement, however, did not seem to have a statistically significant correlation (P<0.05) with the expression of these enzymes.

Conclusion: The study confirms that distinct expression of MMP-3 and -8 is found in the condylar surface of TMJs with internal derangement.