RESUMEN
OBJECTIVE: A systematic review (SR) was conducted to answer the following focused question based on PICO strategy: In patients who were submitted to harvesting palatal free gingival graft, could platelet-rich fibrin (PRF) application in comparison with another method improve the healing, pain, and control of postoperative bleeding in the palatal area in randomized clinical trials? METHODS: A SR was conducted according to the PRISMA guidelines. The MEDLINE (PubMed), Scopus, Embase, and Web of Science databases were searched, and hand searches were made, covering the period up to August 2020, for randomized clinical trials (RCTs) reporting the effect of PRF membrane in postoperative palatal healing management compared with any other methods. The risk of bias (RoB) of the studies included was assessed by using the RoB 2 tool. RESULTS: The electronic search strategy identified 150 articles. After title screening and abstract reading, 141 studies were excluded, and 9 full-text publications were comprehensively evaluated. Finally, 8 articles were included in the systematic review. Six studies showed that the PRF membrane was effective in improving wound healing during the first 2 weeks. As regards patient-centered outcomes, five studies showed that PRF promoted less postoperative pain. Finally, five studies that evaluated bleeding showed that the PRF membrane improved control of postoperative bleeding. RoB was classified as low in 4 studies, 3 with some concerns, and only one study did not describe the outcome data, and as this was missing, it was not possible to verify the protocol of data analysis for this study; therefore, it was classified as having high RoB. CONCLUSION: Within the limitations of this study, the collective evidence emerging from this SR may support the use of PRF membrane in the palatal area after free gingival graft harvesting. The results of this review must be interpreted with caution, due to the low number of RCTs included and high degree of heterogeneity among the PRF protocols. Further well-designed RCTs with accurate protocol and standard PRF parameters are required in order to gain clear understanding of the influence of PRF on wound healing and patient-centered outcomes. CLINICAL RELEVANCE: The use of PRF membrane for the protection of the palatal donor site following free gingival graft harvesting procedures improves wound healing and patients' quality of life.