Relevance. According to the conclusion of the European Federation of Periodontology, late complications of dental implantation include inflammation of the tissues in the reimplantation zone after the completion of osseointegration in the form of periimplantation mucositis and reimplantitis. According to many authors, in the first two months after dental implantation, in the case of initial insufficiency of soft tissue thickness in the operation area, when a minimum volume of biological width (3 mm on average) is formed, bone tissue loss is provoked, this property is especially pronounced when using lamellar dental implants. In the maxilla, overimplantation of a massive plate implant can lead to the development of inflammation of the paranasal sinuses. The most traditional options for mucosal augmentation in the area of implantation in the maxilla are grafting with local tissues or autotransplantation of a free flap from a donor site. Also used are resorbable collagen matrices (Resorbable Collagen Matrix – RCM) or membranes that protect the underlying tissues from external influences, completely close the surgical wound, prevent pathological scarring and allow you to control the epithelialization process.

The purpose of the study. To increase the effectiveness of complex treatment of complicated reimplantitis in the maxilla, sinusoethmoiditis, by sanitation and the use of a collagen membrane for the combined closure of the oro-antral fistula.

Material and methods. The article is devoted to the clinical case of complications of the use of a lamellar dental implant in the maxilla, diagnosis and treatment by an interdisciplinary surgical team of the City Clinical Hospital N.I. Pirogov of the Department of Healthcare of Moscow. A staged surgical intervention for the removal of a detailed laminar implant, unilateral ethmoidotomy and maxillary sinusectomy, and combined closure of the oro-antral communication with the use of local tissue plasty with a flap from the cheek and the installation of a collagen membrane are described.

Results. To close a large bone defect in the area of the alveolar part of the maxilla, the bioPLATE Contur membrane was used, which is characterized by increased extensibility up to 50% of the original dimensions and elasticity. The mucoperiosteal flap was laid without tension over the collagen membrane and fixed with two-row interrupted sutures. The sutures were removed on the 14th postoperative day, the wound was epithelialized throughout, without signs of inflammation.

Conclusions. Complications of dental implantation in the maxilla are manifested in the form of a loss of bone volume and a defect in the alveolar margin of the maxilla, the development of inflammatory complications of adjacent tissues and anatomical structures. This requires a multidisciplinary approach in diagnosis and surgical treatment with a comprehensive planning of patient rehabilitation. The use of a combined method of closing a bone defect with a collagen resorbable membrane and a buccal mucoperiosteal flap with suturing with a double-row suture makes it possible to achieve a satisfactory course of the postoperative period, avoid recurrence of the oro-antral fistula, and prepare the patient for further dental rehabilitation.