Synovial fluid levels of VEGF and FGF-2 before and after intra-articular injection of hyaluronic acid in patients with temporomandibular disorders: a short-term study

Our purpose was to measure the temporomandibular joint (TMJ) synovial fluid (SF) levels of vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) before and after intra-articular injection of hyaluronic acid (HA) and to investigate the possible mechanism involved in the therapeutic value of HA. We analysed the synovial fluid of 30 patients with unilateral internal derangement (ID) or osteoarthritis (OA) of the TMJ (confirmed by magnetic resonance imaging and cone-beam computed tomography) and recorded clinical signs and symptoms including maximal mouth opening, subjective joint pain, and joint noise at the patient's each visit. All clinical signs significantly improved after injection of HA, and there was no significant difference between ID and OA groups. In synovial fluid parameters, the concentration of VEGF was significantly higher before treatment with HA than after treatment, but there was no significant difference in the concentration of FGF-2 between before and after treatment. The study findings suggest intra-articular injection of HA may reduce the synovitis and improve the internal state of the TMJ in a short period.