Objective. To investigate whether matrix metalloproteinases (MMPs) and/or aggrecanase in synovial fluid can be used as biochemical markers in the diagnosis of internal derangement (ID) of the temporomandibular joint (TMJ).
Study design. Forty-four samples of synovial fluid were obtained from 35 patients with ID and osteoarthritis (OA) and 15 normal samples from 10 asymptomatic volunteers. MMP-2, -9, and aggrecanase in the synovial fluid were examined by immunoblotting.
Results. The incidences of MMP-2, -9, and aggrecanase expression in the ID and OA group were significantly higher than those in the normal group (P <.05). Those with anterior disc displacement without reduction and severe OA showed significantly high expression of MMP-9 compared with other disease subgroups (P <.05). Conversely, comparatively high expression of MMP-2 and aggrecanase was shown in the early-stage OA group. However, there was no significant difference in expression of MMP-2 and aggrecanase among disease subgroups.
Conclusions. These findings suggested that expression of aggrecanase could be a potential biochemical marker for articular cartilage degradation in ID of the TMJ.