The aim of the study was to evaluate the effectiveness of platelet-rich fibrin (PRF) for closer of oroantral communication (OAC) during two months of clinical and radiographical follow-up. Eleven patients of both sexes(45.5% males ,54.5% females) included in this study who had (OAC) after dental extraction. The closer was done by using fibrin clot which was plugged into the alveolar socket of the extraction site that contains the communication, and then we sutured the fibrin membrane to the gingival borders above it. The results revealed that (PRF) can close the oroantral communication successfully in 81.8% of the sample with the following complications :pain 27.3% , edema 18.2% , dehiscence 18.2%. We conclude that platelet-rich fibrin can close oroantral communication that results from dental extraction when it has been used as a clot and membrane together with simple complicated subsequent clinical symptoms and without radiographical signs of inflammation of the maxillary sinus.