I removed a failed implant at the maxillary first molar site. After removal of the implant, I placed Beta Tricalcium Phosphate (bTCP) into the implant site and sutured the buccal and palatal flaps closed. It has remained closed and looks normal 4 days post-op, but the patient complains of severe pain and drainage from the sinus. My guess is that some bone graft particles (200 to 500 microns in size) perforated the membrane and went into the sinus. The patient is on 500mg azithromycin twice daily and yet he is not seeing any remission. Should I change his antibiotic regimen or should I open up and remove graft particles – although in this case I would have to close an obvious oroantral communication. Please advise.