METHOD FOR ASSESSING BONE TISSUE OF ALVEOLAR RIDGE OF LOWER JAW IN PREPARATION FOR DENTAL IMPLANTATION Russian patent published in 2023 - IPC A61B5/107 A61B6/02 A61B6/14 

FIELD: surgical; orthopaedic dentistry.

SUBSTANCE: invention can be used to assess the bone tissue of the alveolar crest of the lower jaw in preparation for dental implantation. Cone-beam computed tomography (CBCT) of the dentition, intraoral scanning or taking impressions is performed, followed by casting of plaster models and their scanning, modelling of future orthopaedic restorations. CT images are loaded into DICOM medical imaging software with an interactive coordinate system and the ability to reorient sectional planes to build reformats. In the coronary and sagittal reformates, the centre of the axes of the section is shifted to the edentulous area of the jaw. On the axial reformat, the section axis is rotated to build the sagittal reformat, so that it passes mesiodistally along the edentulous jaw area. On the sagittal reformate, the section axis is rotated to build the coronary reformat, so that it passes through the centre of the future orthopaedic crown, along the vertical axis of the implant, determined at the preliminary planning stage and transferred with a reference to anatomically unchanged structures. On the coronary reformat, the sectional axis, which serves to build the sagittal reformat, is rotated so that it runs along the vertical axis of the implant. The cut of the alveolar ridge in the coronary reformate is rotated in such a way that the sectional axis, which serves to build the coronary reformat, is located vertically. In the sagittal reformat, the thickness of the selected layer of the section axis, which serves to construct the coronal reformat, is set to 3 mm. On the resulting cut of the alveolar ridge in the area of the future implant installation in the coronary reformat, a horizontal line is drawn along the upper border of the mandibular canal and another horizontal line is drawn along the top of the alveolar ridge and the distance between them (H) is measured. The width of the alveolar ridge is measured at the level of its top along a horizontal line drawn along the top of the alveolar ridge, and at distances of 1 mm, 3 mm, 5 mm from it along lines parallel to it. A virtual analogue of the implant planned for installation is placed parallel to the constructed axes of section in the coronary and sagittal reformat at a distance of at least 2 mm from the horizontal line along the upper border of the mandibular canal and at least 1.5 mm from the lingual undercut. If at levels of 1 mm, 3 mm, 5 mm from the edge of the implant to the surface of the alveolar ridge, at least 1.5 mm of bone tissue is determined in the vestibular and lingual directions, and the length of the implant is more than or equal to 8 mm, the volume of bone tissue is considered sufficient for implantation operations, otherwise perform bone grafting of the alveolar ridge and not earlier than 6 months later re-evaluate the bone tissue of the alveolar ridge, performing the same sequence of actions as before bone grafting of the alveolar ridge, and the difference is that on the cut of the alveolar ridge on the CT image in the coronary reformat, a horizontal line is drawn along the upper border of the mandibular canal, and a reference line is drawn along the upper border of the mandibular canal at a distance H from the horizontal line. After that, parallel to the reference line, a horizontal line is drawn along the top of the newly formed alveolar ridge, the height of the newly formed ridge is measured, at distances of 1 mm, 3 mm and 5 mm from the reference line, bone tissue is measured and evaluated, as well as before bone grafting of the alveolar ridge.

EFFECT: effective implant treatment by evaluating the parameters of the edentulous alveolar ridge before and during the process of replenishing the missing volume of bone tissue.

1 cl, 33 dwg, 2 ex