METHOD FOR ELIMINATION OF DEFECT OF MIDDLE ZONE OF FACE AFTER RESECTION OF MAXILLOFACIAL TISSUES Russian patent published in 2024 - IPC A61B17/16 A61C8/00 A61B17/88 A61B6/03 G16H30/20 A61C13/34 

FIELD: medicine.

SUBSTANCE: invention relates to maxillofacial surgery. Performing virtual modeling according to computed tomography data and obtaining configurations of bone structures, which correspond to the contours of the lost parts of the facial skull of the patient. Zygomatic implants are positioned in the area of the defect, taking into account the requirements of the planned orthopedic structure supported on them. Based on the virtual simulation, a zygomatic implant positioning template is simulated with a polished part of the zygomatic implant body in the zygomatic bone and positioning the zygomatic implants from the opposite side. Software is used to select the position and angle of the zygomatic implant. Virtual simulation is followed by a surgical intervention. First stage of the surgical intervention involves an incision on the opposite side of the defect from the vestibular surface of the upper jaw from the lateral incisor to the first molar. Then, two vertical incisions are made, the distal one being located along the distal edge of the sub-zygomatic crest. Mucoperiosteal flap is detached and a palatal surface of the alveolar crest and a hard palate are exposed. Further, a medial surface of a zygomatic bone body and a zygomatic arch is peeled off to the zygomatic notch and the retractor is fixed. Further, the first preparation is started with a pilot ball-shaped bur from the palatal side of the upper jaw in the area of the missing teeth, perforating the zygomatic bone with sodium chloride irrigation. Preset trajectory and direction of the bur is visually controlled with a surgical template when passing a maxillary sinus in a projection of a lower zygomatic crest to perforation of an internal cortical layer of the zygomatic bone. Apical part of the bed is formed by drills with a gradually increasing diameter of the drills to perforation of the external cortical layer of the zygomatic bone. Further, the probe is used to measure the osteotomy depth. Zygomatic implant is installed with involvement of external cortical layer of zygomatic bone. Zygomatic implant, made self-tapping, with length of 27–60 mm with diameter of 3.5–4.1 mm, is introduced into the prepared bed using an implant driver for tip 20:1 with torque of 45 N. Last revolutions are completed mechanically using a torque screwdriver. Torque is 70 N. Zygomatic implant platform is positioned parallel to an occlusal plane with an outlet of the fixing screw shaft with angle of 45–55° relative to the zygomatic implant body. Second preparation and introduction into the prepared bed of the zygomatic implant is performed in the distal portions in the area of the missing teeth similarly to the first preparation. Second stage of the surgical intervention is followed by a horizontal incision from the opposite side in the area of the post-resection defect of the upper jaw in the middle of the zygomatic bone stump in the post-resection region. Mucoperiosteal flap of a medial surface of a zygomatic bone body and a zygomatic arch is detached. Retractor is passed to the zygomatic notch. Zygomatic implants with a polished portion are marked and positioned in the zygomatic bone stump using guide templates. Further, the third preparation is started with a pilot ball-shaped bur, forming a bed under the zygomatic implant and perforating the zygomatic bone with irrigation with sodium chloride. Preset trajectory and direction of the bur is visually controlled with a surgical template. Further, the probe is used to measure the depth and direction of the zygomatic implant, after which the zygomatic implant is installed with the involvement of the external cortical layer of the zygomatic bone. Zygomatic implant with length of 27–60 mm with diameter of 3.5–4.1 mm with a working part immersed in the bone, is introduced into the prepared bed using an implant driver for tip of 20:1 with torque of 45 N and the last revolutions are completed mechanically using a torque screwdriver. Torque is 70 N. Zygomatic implant platform is positioned parallel to an occlusal plane with an outlet of the fixing screw shaft with angle of 45–55° relative to the zygomatic implant body. Fourth preparation and introduction into the prepared bed of the zygomatic implant is performed in the distal portions similarly to the third preparation. Zygomatic implant is placed in the area of the zygomatic bone, and the positioning of the platform relative to the occlusal plane is controlled. Then the implant driver is removed and the healing abutment is fixed. Edges of the mucoperiosteal flap are matched, covering the polished part of the zygomatic implant, and the wound is closed by means of interrupted and blanket sutures. After the surgical intervention, the patient is prescribed an antibacterial therapy and anti-inflammatory drugs and assessing the state of the zygomatic bone and upper jaw in the area of the zygomatic implants for the absence of inflammatory phenomena. That is ensured by a panoramic orthopantomogram, followed by a panoramic image in a direct projection. Oral cavity is treated with an antiseptic solution after each meal 3 times a day. In 48 hours after the operation, a screw-retained orthopedic structure is made on the zygomatic implants.

EFFECT: method enables to perform low-traumatic elimination of the defect of the middle zone of the face after resection of tissues of the maxillofacial region, provides functional and aesthetic restoration within a single surgical intervention, as well as accurate installation and positioning of the zygomatic implant.

3 cl, 25 dwg, 1 ex