Comparison of Autologous Conditioned Serum and Platelet‐Rich Plasma Following Arthrocentesis in Temporomandibular Joint Osteoarthritis: A Randomized Clinical Trial

ABSTRACT Background Temporomandibular joint osteoarthritis (TMJ‐OA) is a degenerative condition that negatively affects quality of life. Although platelet‐rich plasma (PRP) is widely used, its efficacy remains controversial. Autologous conditioned serum (ACS), which targets inflammation via interleukin‐1 receptor antagonist (IL‐1Ra), has emerged as a novel biological therapy. Objective To compare the effects of two autologous biological agents, PRP and ACS, used as adjuncts to arthrocentesis, on pain, maximum mouth opening (MMO) and joint sounds in patients with TMJ‐OA. Methods This randomized, single‐centre clinical trial with blinded outcome assessment and statistical analysis included 75 patients with TMJ‐OA. Participants were allocated to three groups: ACS, PRP and control ( n = 25 each). All patients underwent arthrocentesis; the ACS and PRP groups received 1 mL intra‐articular injections, while the control group received no additional treatment. Outcomes were assessed at baseline, 1 week, 1 month, 3 months and 6 months by a blinded assessor. Pain was evaluated using a visual analogue scale (VAS), MMO was measured in millimetres and joint sounds were clinically assessed. Results Baseline characteristics were comparable among the groups. From the first week onward, significant differences in VAS and MMO were observed at all follow‐up time points ( p < 0.001). Both ACS and PRP groups demonstrated greater improvement compared to the control group. However, no consistent statistically significant differences were observed between the two treatment groups. Joint sounds decreased significantly in both treatment groups, particularly at later follow‐up periods. Conclusion Both ACS and PRP following arthrocentesis improved clinical outcomes in TMJ‐OA, with no consistent superiority between treatments. Trial Registration ClinicalTrials.gov : NCT06839326