The reconstruction of atrophic posterior maxilla by split osteotomy technique and sinus lift with mucous retention cyst removal. Clinical case; [Реконструкция дистального отдела альвеолярного отростка верхней челюсти методом межкортикальной остеотомии и синус-лифтинга с удалением кисты верхнечелюстной пазухи. Клинический случай]

The aim was to demonstrate the possibility of combined reconstruction of the posterior maxilla by split osteotomy and sinus lift with antral pseudocyst (AP) removal of the maxillary sinus (MS). Materials and Methods. This article presents a clinical case of rehabilitation of a patient with partial adentia (K08.1), atrophy of the edentulous alveolar ridge (K08.2), AP of the maxillary sinus (J34.1). Adentia was noted in the projection of teeth 2.3-2.7. According to CBCT, the height of the alveolar ridge averaged 4.4 mm and width was 4.2 mm. An 18×24×20 mm AP was detected on the inferior wall of the left MS. Prosthodontics with implant-supported crowns were planned. At the first surgical stage bone reconstruction and AP removal in one stage was planned. The surgery was performed under local anesthesia with premedication. The AP was removed through an artificial perforation of the MS mucosa after mobilization of the Schneider's membrane. The mucosal defect was repaired with 1 tightening suture and a collagen membrane. The reconstruction area was filled with a 1:1 mixture of autogenous shavings and xenogeneic graft and overlapped with a collagen membrane after alveolar ridge splitting. The wound was sutured with combined sutures. Postoperative appointments were given considering the risk of developing sinusitis. Results. There were no signs of sinusitis after 6 months. Bone formation averaged 13.7 mm in height and 7.1 mm in width and was sufficient for implantation. The achieved results were stable 5 years after prosthetics. Conclusions. The presented method allowed us to optimize the stages and time of reconstruction of the posterior maxilla: we managed to combine bone grafting and sanation of the maxillary floor. We did not find our proposed method in the available literature. © 2020 Clinical Dentistry LLC. All Rights Reserved.