FIELD: medicine.SUBSTANCE: invention refers to medicine, particularly to orthopaedic dentistry, and is intended for use in complex jaw prosthesis of patients with extensive defects of maxillofacial tissues. Bone defect of upper jaw of patient is tightly covered with moist sterile tissues so that edges of defect remained open to depth of 5–10 mm. Impressions are taken from both jaws by alginate or silicone mass, according to which models from gypsum are moulded. Model of the upper jaw is installed on the platform of the vacuum apparatus and squeezed on it with a standard plate of silicone. Squeezed plate is removed from gypsum model of upper jaw, obturating part of plate is cut with scissors or cutter so that edges of plate overlap along entire perimeter of bone defect by 5 mm. Obturating plate in the form of a "hat with margins" is fitted in a bone defect of the upper jaw and an impression of the upper jaw is taken with an alginate or silicone mass. Impression is cast by gypsum, having removed from it a plate in the form of a "hat with fields". Further, a wax base with wax beads is made, central occlusion or central ratio of jaws, artificial teeth is determined. Fitting the wax structure of the prosthesis in the oral cavity, prosthesis polymerisation, treatment and polishing. In the oral cavity, the obturating part of the prosthesis of a thin plate in the form of a "hat with margins" is first pre-inserted, and a replacement resection prosthesis is fitted in which the occlusive portion of the main prosthesis tightly enters the removable obturating part from the silicone plate. For better sealing obturating parts can be lubricated with Corega gel.EFFECT: use of this prosthesis provides dense defect obturation of the defect in the nasal or maxillary sinus cavity with the possibility of fast replacement of the occlusive part at its infection or change of the size or shape of the defect without change of the resectional prosthesis, facilitated fitting of the occluding pr
