Closure and Reconstruction of Oroantral Communication Caused by Peri-Implantitis Following Maxillary Sinus Augmentation: A Case Report

A 60-year-old female patient was referred for the closure of an oroantral communication (OAC) that developed at the site of the maxillary second molar.The cause was severe bone resorption and destruction of the maxillary sinus floor due to peri-implantitis in an implant placed with sinus augmentation.The OAC was closed using a buccal advanced flap combined with a connective tissue (CT) graft.Shortly thereafter, a similar course occurred at the implant placed at maxillary first molar, which was removed and treated using the same method.After confirming OAC closure and allowing sufficient soft tissue healing, the maxillary bone was reconstructed through lateral window sinus augmentation.Subsequently, implants were reinserted in stages, and following progressive loading with a provisional restoration, final prostheses were delivered.