METHOD FOR PREOPERATIVE PLANNING OF ORTHOGNATIC SURGERY IN PATIENTS WITH CONGENITAL ANOMALIES OF JAWS Russian patent published in 2020 - IPC A61B5/00 

FIELD: medicine.

SUBSTANCE: invention relates to the field of medicine, namely to surgical dentistry and maxillofacial surgery, to a method for preoperative planning of orthognatic surgery in patients with congenital anomalies of jaws, and can be used in conditions of maxillofacial, dental department, as well as other medical institutions. Disclosed is a method for preoperative planning of orthognatic surgery in patients with congenital anomalies of jaws, characterized by the fact that preoperative period before orthognatic intervention is determined by method of cone-beam computed tomography volume and the size of the surgical dentoalform anomalies of the area from the superciliary arcs to the edge of the body of the lower jaw of the patient in the natural position of the head, the obtained tomographic information is stored in a DICOM format and transferred into Dolphin Imaging, using 3dMDface camera of 3D patient's head photo in a natural position (HNP) with its location between two modular units comprising six chambers synchronized in one grip, at photographing speed of 1.5 millisecond with geometric accuracy ≤0.2 mm from 180° covering the patient's head from ear to ear, performing the obtained photographs rendering for 7–8 seconds with their preservation in the OBJ format, upper and lower jaws of the patient with developing abnormalities are made using Zher-mack Hydrogum impression mass to obtain their impressions, cast models of upper and lower jaw casts are molded by casting of prepared impressions with prepared mass of dental gypsum grade 4 using a vibration table and after 30–35 minutes, plaster models are removed from imprint, method includes scanning plaster models in an optical narrow-band scanner Zirkozahn S600 ARTI at scanning accuracy of 10 mcm and rotating models about its axis by 360° with inclination angle from vertical axis by 100° and obtained scans are stored in STL format, alignment with accuracy of 0.1 mm of the results of conical-beam computed tomography, 3D photo of the patient's head and scanning of the gypsum models is performed using the Dolphin Imaging program, performing virtual movements of bone fragments and forming a virtual surgical splint, which is manufactured using 3D printing or milling CAD / CAM for subsequent use of the forthcoming orthognatic operation, volume of movements of bone fragments of the upper and lower jaws of the patient is virtualized for reproduction when performing the forthcoming orthognatic operation.

EFFECT: invention provides sufficient accuracy and visualization of creating the required jaw position when planning orthognatic surgery in patients with jaw anomalies, significant reduction of the risk of postoperative complications of the planned orthognatic interventions, possibility to assess results of orthognatic intervention with simultaneous achievement of the specified aesthetic result on postoperative position of soft tissues of the patient's face.

1 cl, 3 ex