Diagnostic Criteria Used in i‐ PRF Trials for Articular Temporomandibular Disorders: A Scoping Review

OBJECTIVE: Injectable platelet-rich fibrin (i-PRF) is increasingly used for articular temporomandibular disorders (TMD), but it is unclear whether randomised controlled trials (RCTs) report validated diagnostic criteria for participant enrolment. This scoping review maps the diagnostic instruments reported in i-PRF RCTs for articular TMD. It does not assess whether diagnostic systems were applied correctly or the accuracy of diagnoses. METHODS: Following the JBI framework and PRISMA-ScR, RCTs evaluating i-PRF for articular TMD and reporting pain and/or maximum mouth opening were searched in six databases, without date or language restrictions, plus grey literature, trial registries and reference lists. Diagnostic approaches, sample characteristics, imaging, interventions, comparators, follow-up and adverse events were charted. RESULTS: Thirteen RCTs were included. Three reported DC/TMD for enrolment, two from the same research group. Five reported Wilkes staging, three reported imaging without a clinical diagnostic system, and two reported no diagnostic criterion. No trial reported RDC/TMD. CONCLUSION: Fewer than a quarter of i-PRF RCTs reported enrolment using a currently validated diagnostic system. This methodological finding does not indicate whether i-PRF is effective. Future trials should use DC/TMD and report diagnostic procedures in full.