Abstract Objectives The aim of this RCT was to clinically evaluate swelling, pain and wound healing following submucosal infiltration of injectable Platelet-Rich Fibrin (i-PRF) after extraction of impacted lower third molar. Materials and methods The study was designed as a double-blinded, parallel group, randomized controlled clinical trial. 56 patients were divided into 2 groups: in the control group the socket was left to heal spontaneously, while the test group was treated with submucosal infiltration of i-PRF. Swelling was measured with a flexible ruler using the diagonals joining Trago and Pogonion, Gonion and labial cleft. The swelling was calculated as the sum of these diagonals before surgery, on day 3 and 7. Pain was assessed by VAS scale until the 7th postoperative day. Surgical wound healing was evaluated by the Healing Index by Landry on 3, 7 ,14 and 21st day postosperatively. The relation between duration of intervention and total swelling was also evaluated. Results 56 patients were enrolled in this study (28 for the test group and 28 for the control group). Randomization resulted in groups with similar baseline characteristics. No patients were lost during the follow-up and no adverse events were noted. On day 3 the total swelling was 12.7 ± 0.92 mm for control group and 12.1 ± 0.75 mm for test group; on day 7 it was 12.3 ± 0.88 mm for control group and 11.7 ± 0.73 mm for test group. A statistically significant difference was found on day 3 ( p = 0.006) and on day 7 ( p = 0.018). The relation between total swelling and duration of intervention was not statistically significant ( p = 0.276). A significant reduction in pain scores was observed in the i-PRF group on days 1 and 3 ( p < 0.001). Surgical wound healing also showed statistically significant improvement in the i-PRF group at all time points (days 3, 7, 14, and 21; p < 0.05). Conclusions Within the limit of our study, this randomized controlled clinical trial suggests that submucosal infiltration of i-PRF after the extraction of impacted lower third molars effectively reduces postoperative swelling and pain, while also promoting faster wound healing. Clinical Relevance The adjunctive use of injectable platelet-rich fibrin (i‑PRF) after surgical removal of impacted mandibular third molars may contribute to improve early postoperative outcomes by attenuating soft tissue inflammation, reducing pain intensity, and accelerating wound healing. By potentially lowering the need for nonsteroidal anti-inflammatory drugs (NSAIDs) and minimizing associated adverse effects, i‑PRF represents a minimally invasive, autologous approach that could enhance patient comfort, reduce recovery time, and support faster return to daily activities.
Aliberti et al. (Fri,) studied this question.