Single intra-articular administration of injectable platelet-rich fibrin (I-PRF) in alleviating temporomandibular joint pain: A pilot clinical trial

Background. Intracapsular injections are a recognized therapeutic method for temporomandibular joint (TMJ) pain and limited mandibular mobility. Among many injectables, injectable platelet-rich fibrin (I-PRF) is noteworthy for its safety, promising clinical results and potential regenerative effects. The minimal invasiveness of a single injection makes it attractive as compared to arthrocentesis or a series of administrations. Objectives. This single-arm, open-label clinical trial aimed to verify the research hypothesis that a single administration of I-PRF intoTMJ relieves articular pain. Material and methods. The study sample included adults with a history of TMJ articular pain treatment. A single injection of I-PRF into the affected TMJ was performed. Each patient assessed (1) articular pain within the last 7 days, (2) the articular pain provoked by a physical examination, (3) muscular pain, (4) headache, and (5) neck pain before and 14 days after the intervention. The investigator measured (6) pain-free and (7) maximal voluntary mandibular abduction. Results. The study sample included 33 patients and 44 TMJs. No adverse events were observed at the recipient sites (TMJs). The treatment reduced the spontaneous articular pain by 0.5 +/- 1.5 and the provoked articular pain by 1.2 +/- 1.9 visual analog scale (VAS) points, with the differences being statistically significant (p < 0.05). Improvement was observed in 39-48% ofWilkes II-V patients, and 5-14% experienced deterioration up to 2VAS points. Mandibular mobility decreased by an average of 1-2 mm, and no statistically significant effect on muscle pain, headache or neck pain was recorded. Conclusions. A single intra-articular injection of I-PRF into TMJ brings statistically significant articular pain relief, regardless of the assessment method. In non-respondents, subsequent administrations may be considered.