The oroantral communication is one of the accidents most common after dental extractions in posterior maxillary region, involving mainly the first molar. The diagnosis must be realized through radiographic and clinical methods (Valsalva's Maneuver) and the treatment must be effect early, avoiding infection of the sinus and installing itself maxillary sinusitis. The treatment of the previous maxillary sinusitis must be instituted before the oroantral fistula plastic closure. The purpose of the study was to report three clinical cases of oroantral communication, furthermore to direct the professionals to the diagnosis and surgical treatment
oroantral fistula; maxillary sinusitis