Endosseous Oroantral Port for Minimal Intervention in Treating Chronic Sinusitis

Inclusion Criteria: * No medical history of diseases involving bone metabolism * Unilateral or bilateral maxillary sinusitis, as evident by radiographic and endoscopic modaleties, which have not responded to optimal conservative treatment * Patient who is edentulous in the maxillary region and is interested in dental implant * The patient does not participate in another clinical study * The patient can read and understand the informed consent Exclusion Criteria: * Medical history of increased risk of developing bone necrosis (MRONJ - medically related osteonecrosis of the jaw , or ORN - osteoradionecrosis) * patients who are not interested or need dental implants * Patients with maxillary sinus neoplastic pathology * Chronic maxillary sinusitis with polyps * Pregnant women