The aim of this study was to evaluate the effectiveness of platelet-rich fibrin (PRF) in repairing of Schneiderian membrane perforations in rabbit maxillary sinus. A total of 42 female New Zealand rabbits were randomly divided into two groups. Symmetrical bony defects were created 1 cm in diameter and the sinus membranes were exposed. The Schneiderian membranes were elevated in both sinuses and each membrane was perforated with a 1 cm incision. No treatment was applied to the right perforations in both groups. Left-sided perforations were closed with collagen membrane in the first group and PRF membrane in the other group. Seven animals randomly selected from each group were sacrificed at weeks 1, 2 and 4 in order to be able to examine the amounts of lymphocytes, fibroblasts, veins, and collagen fibers in the area where the membranes were applied. Histological analyses showed that there were no statistically significant differences between the collagen membrane and the PRF membrane in the healing of sinus perforation area. PRF may be considered as an alternative application to collagen membrane in sinus membrane perforations. (C) 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.