Bone grafts to the maxillary sinus are often required after closure of an oroantral fistula (OAF) to allow for subsequent implant installation. This report describes a single procedure that closes a large OAF using bone grafting to the involved sinus. This technique involves sinus mucosal lifting via elevating the sinus membrane, which is recovered as a continuous layer by combining the residual sinus membranes with a rotated part of oral mucosa around the OAF. Autogenous bone from the ilium was grafted into the prepared sinus space, and the oral side of the graft was covered by a rotated palatal flap. This technique was used to treat 3 patients who had large OAFs in the atrophied posterior maxillary region owing to previous multiple implant failures after sinus lifting. The treatment was successful in all cases. This technique appears to be suitable for large OAFs where implants are subsequently desired.