Abstract:

Objective　To study the gene expression changes in extracelluar matrix of condylar cartilage following disc anterior displacement of rabbit TMJ.Methods　The right sides of 28 joints in 40 rabbits were subjected to surgical operation of disc dis- placement. The condylar CollagenⅡand Aggrecan mRNA expression were detected byin situhybridization.Results　Collagen II and Aggrecan mRNAmainly expressed in the lower zone of condylar chondrocyte. Aggrecan mRNA decreased faster than colla- gen II following disc displacement, and adjusted to normal later.Conclusion　Anterior disc displacement leads to alteration of ex- tracellurar matrix gene expression in the condylar chondrocyte, which means the start of remodeling.

Key words: temporomandibular joint, disc displacement, collagenⅡ, aggrecan, in situhybridization