The objective of this study was to investigate and compare the clinical effectiveness of the application of platelet-rich fibrin (PRF) and conventional flap surgery for the treatment of peri-implant bone loss. Nineteen patients (8 women, 11 men) with peri-implant bone loss were randomly allocated to two groups, with the PRF group comprising patients who received fibrin scaffold and the control group made up of those who received only the access flap. At 3 and 6 months after surgery, respectively, the PRF group demonstrated higher mean probing depth reductions (2.41 ± 1.06 and 2.82 ± 1.03 mm versus 1.65 ± 1.02 and 2.05 ± 0.77 mm) and more gains in clinical attachment level (2.89 ± 1.01 and 3.31 ± 1.08 mm versus 1.43 ± 1.08 and 1.84 ± 0.81 mm) compared with the control group. In addition, the increase in the amount of keratinized mucosa from baseline to 6 months postoperatively was statistically significant for the PRF group (P .001). Hence, the data from the current study led to the conclusion that PRF application in periimplant bone loss provided better clinical results than conventional flap surgery.