Abstract

The aim of this study was to investigate the influence of tumor necrosis factor-α (TNF-α) in temporomandibular joint (TMJ) synovial fluid and blood on the treatment effect on TMJ pain by intra-articular injection of glucocorticoid in patients with chronic inflammatory TMJ disorders. High pretreatment level of TNF-α in the synovial fluid was associated with a decrease of TNF-α and elimination of pain upon maximal mouth opening. Elimination of this TMJ pain was accordingly associated with decrease in synovial fluid level of TNF-α. There was also a significant decrease of C-reactive protein and TMJ resting pain after treatment. In conclusion, this study indicates that presence of TNF-α in the synovial fluid predicts a treatment effect of intra-articular injection of glucocorticoid on TMJ movement pain in patients with chronic TMJ inflammatory disorders.