Effects of injectable platelet-rich fibrin (i-PRF) application as root surface biomodification on gingival fibroblasts: an in vitro study.

BACKGROUND: Root surface biomodification (RSB) enhances tissue attachment by removing the smear layer, facilitating collagen fibril formation, and promoting clot formation and stabilization. This study aimed to evaluate the efficacy of injectable platelet-rich fibrin (i-PRF), an autologous blood product, as a potential adjunct to ethylenediaminetetraacetic acid (EDTA) for RSB in gingival fibroblast attachment and proliferation in vitro. METHODS: Dentin discs (4 mm in diameter) underwent root surface debridement to remove damaged cementum. The discs were treated with 24% EDTA, followed by the application of i-PRF for 1, 3, 5-min. Enamel matrix derivatives (EMD) were used as a positive control (5 min application), while untreated discs served as the negative control. Cell viability was assessed using the XTT assay. Cellular morphology was examined via scanning electron microscopy (SEM), and cytoskeletal organization was analyzed using fluorescence microscopy (FM) analysis. Intracellular and extracellular alkaline phosphatase (iALP/eALP) gene expression levels were evaluated. Data was analyzed using ANOVA. RESULTS: XTT analysis revealed no statistically significant difference in cell viability between the i-PRF and the EMD groups at different time points. Actin filament organization was evident in the i-PRF 3-min group and became more pronounced in the i-PRF 5-min and the EMD groups. The i-PRF 3-min, i-PRF 5-min, and the EMD groups exhibited a spindle-shaped fibroblast morphology. No statistically significant difference was observed in iALP levels between the i-PRF 5-min and the EMD groups (p > 0.001). The EMD group exhibited the highest eALP level (p < 0.001), while the i-PRF 3-min and 5-min groups demonstrated the second highest levels. CONCLUSION: The application of i-PRF for 5 min following EDTA treatment appears to enhance gingival fibroblast proliferation, attachment, and ALP expression. The effectiveness of i-PRF may vary depending on the duration of the application. Therefore, in vitro data from i-PRF followed by EDTA application to dentin surfaces may be useful for further development of in vivo and clinical approaches.