Prostaglandin E2 in temporomandibular joint synovial fluid and its relation to pain and inflammatory disorders

Purpose: The aim of this study was to investigate temporomandibular joint (TMJ) synovial fluid (SF) levels of prostaglandin E-2 and its relation to general inflammatory activity and its influence on specific TMJ pain in patients with inflammatory TMJ disorders. Patients and Methods: The study comprised 24 patients (30 joints) with inflammatory TMJ disorders and 4 healthy persons (6 joints). TMJ pain at rest, tenderness to palpation of the TMJ, and TMJ pressure pain threshold, as well as pain during joint movements (PM), were assessed. PGE levels were analyzed in synovial fluid samples (SF-PGE(2)) and blood plasma (P-PGE(2)), The erythrocyte sedimentation rate (B-ESR) as well as the serum levels of C-reactive protein (S-CRP) and antinuclear antibodies were determined. Results: PGE(2) was undetectable in the plasma find in the TMT SF of the healthy persons. In the patients, PGE(2) was detectable in 20 of the 30 (67%) SF samples. SF-PGE(2) was significantly :Ind positively correlated to PM in the patients. There were significant correlations between P-PGE(2) and B-ESR as well as the S-CRP, Conclusions: This study shows that the synovial fluid in patients with TMJ inflammatory disorders frequently has a detectable level of PGE(2) that is related to TMJ allodynia. The plasma levels of PGE(2) seem to be related to the general inflammatory activity in these patients.