Evaluation of the Short-Term Influence of Intra-Articular Platelet-Rich Plasma Injection in Patients with Temporomandibular Joint Internal Derangement: A Randomised, Saline-Controlled Clinical Study

Temporomandibular joint disc displacement commonly causes pain, joint sounds, and limited mouth opening, yet the optimal minimally invasive treatment remains uncertain. Platelet-rich plasma, an autologous concentrate of growth factors, has been proposed to encourage intra-articular repair, but placebo-controlled evidence is limited. This randomised, saline-controlled trial compared a single intra-articular injection of platelet-rich plasma with normal saline over the short term. Twenty joints were randomised 1:1 to platelet-rich plasma or to 0.9% normal saline as a control. Pain (10-point visual analogue scale), joint sound (0–2 ordinal scale), and maximum interincisal opening (in millimetres) were recorded at baseline and at one week. Within-group change was assessed with the exact Wilcoxon signed-rank test and between-group differences with the Mann–Whitney U test (two-sided; significance level 0.05). The groups were comparable at baseline (all p > 0.05). With platelet-rich plasma, median pain fell from 7.5 to 2.0 (p = 0.002), clicking resolved in 70% of joints, and median opening rose from 43.5 to 44.5 mm (p = 0.008). Saline changed none of the three outcomes (pain p = 1.000; opening p = 0.625; no joint lost its click). Between groups, platelet-rich plasma was superior for pain (p < 0.001), joint sound (p < 0.001), and opening (p = 0.020), with large effect sizes. Because saline produced no change, the improvements are unlikely to reflect the needle or a placebo effect and more plausibly indicate a genuine, though preliminary, treatment response. Platelet-rich plasma appears to be a potentially useful, minimally invasive option for temporomandibular joint internal derangement, although larger trials with longer follow-up are needed to confirm this.