Injectable platelet rich fibrin effect on laser depigmented gingiva: a clinical randomized controlled split mouth trial with histological assessment.

Objective: To determine whether intra-mucosal injection of injectable platelet-rich fibrin (i-PRF) can promote healing after Diode Laser Gingival Depigmentation (DLGD).

Methodology: A total of 20 arch sites of hyperpigmented gingiva of 10 patients underwent DLGD. For each patient, two arch sites were randomly assigned for either intra-mucosal injection of i-PRF (G1-i-PRF) (n=10 sites) or no treatment (G2-Control): (n=10 sites). Wound Healing Score (WHS), patient satisfaction, and Pigmentation Index (DOPI) were measured at 1 week and 1 and 3 months postoperatively. Histological assessment of tissue specimens was performed at baseline and 1 week.

Results: The percentage change in WHS at 1 week was significantly higher in G1 (58.34±15.43) compared to G2 (37.50±11.79). At day 1, 50% of patients in G1 were pain free compared with 75% in G2, who had mild pain. Mean DOPI decreased significantly at 3 months in both groups (P-value <0.001), without significant differences between groups. G1 specimens showed significantly higher epithelial thickness (P-value <0.001), as well as a higher number of blood vessels and less percentage of inflammatory cells.

Conclusions: i-PRF demonstrated better clinical and histological healing potential and less patient discomfort compared to sites without treatment after DLGD. Registered at https://clinicaltrials.gov/ as (NCT05283668).