Matrix metalloproteinase-2 in synovial lavage fluid of patients with disorders of the temporomandibular joint

We examined the matrix metalloproteinase-2 (MMP-2) activity in synovial lavage fluid of patients with disorders of the temporomandibular joint (TMJ) and explored the possible correlationship between MMP-2 activity and radiological changes. We studied 86 patients and 10 healthy volunteers. An arthrogram and a double contrast arthrotomogram were taken to evaluate intra-articular morphological changes. The patients were divided into three groups: no abnormality (n = 36), internal derangement (n = 39), and osteoarthritis (n = 11). Samples of synovial fluid were studied by gelatin zymography, and we sought a correlation between the band detected and radiological findings. ProMMP-2 was detected in all samples and active MMP-2 was detected in 9/36 with no abnormality, 14/39 with internal derangement and 5/11 with osteoarthritis. No active form of MMP-2 was detected in the control group. The incidence of active MMP-2 was high in the internal derangement group and highest in the osteoarthritis group, which suggests that active MMP-2 plays an important part in the development of conditions of the TMJ.