RU2714618C1 - Method for augmentation of atrophied part of alveolar process of jaw - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to surgical and orthopedic dentistry, and can be used for augmentation of atrophied part of alveolar process of jaw. For this purpose, an individual titanium membrane repeating the shape of the defect, including holes for filling the augmentation zone and holes for fixing screws. For making the membrane, an X-ray examination of the jaw is performed using a cone-beam computer tomography. Obtained data in DICOM format is converted to .stl format and used in software 3 Shape to recreate model of lost bone tissue volume of alveolar process, creating 3D model of defect area and 3D model of individual membrane with holes. Using 3D printing by means of laser sintering from titanium dust there made is individual membrane with thickness of 0.3 mm with holes. Membrane is installed with overlapping augmentation zone, fixed and filled with autobone chips mixed with artificial material xenograft in ratio 1:1.

EFFECT: invention provides reducing operation time and postoperative complications.

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Description

The invention relates to medicine, namely to surgical and orthopedic dentistry and can be used for augmentation of the atrophied part of the alveolar process of the jaw.

There is a method of augmentation of the atrophied part of the alveolar process of the jaw, including an incision in the area of the defect of the jaw, peeling of the mucosal-periosteal flap, mobilization of the flap, skeletal bone tissue of the outer surface of the alveolar process and perforations in the cortical layer, filling the augmentation zone with a mixture of autologous bone material and autologous bone , overlapping the augmentation zone with a limiting membrane in the form of a titanium mesh and its fixation, suturing of the wound (Titanium mesh and particulate cancellous bone and mar row grafts to augment the maxillary alveolar ridge. R.K. Gongloff, M. Cole, W. Whitlow, PJ Boyne // International Journal of Oral and Maxillofacial Surgery, Volume 15, Issue 3, June 1986, Pages 263-268). This method is the closest analogue.

The disadvantage of this method is the need to adapt the titanium mesh to the recipient area individually for each patient during surgery. This product is manufactured by the factory method, has a rectangular or square shape and goes on sale only a certain size. During the bone augmentation surgery, it is necessary to cut out the mesh of the desired size and bend it in the shape of the defect, which sometimes takes a lot of time and requires repeated fitting. In addition, using a titanium mesh, it is impossible to repeat the individual anatomy of the patient's jaw. It is only possible to approximately adjust the volume of bone tissue, based on the defect. Another disadvantage is the need to overlap the titanium network on top of the collagen membrane in order to prevent immersion growth from the epithelium of the mucous membrane.

The technical result of the invention is the restoration of the anatomy of the original bone tissue, the creation of an individual membrane of any complexity, the reduction of operating time, the absence of the need to correct an individual membrane during surgery, the possibility of wearing temporary prostheses in the early postoperative period, the absence of the need to remove the membrane in case of partial exposure, reduction of postoperative complications, improved aesthetic results.

The specified technical result is achieved in the method of augmentation of the atrophied part of the alveolar process of the jaw, including an incision in the area of the jaw defect, peeling of the mucosal-periosteal flap, mobilization of the flap, skeletonization of the bone tissue of the outer surface of the alveolar process, perforation in the cortical layer, filling of the augment area and augmentation mixture osteoplastic material, the installation of a titanium membrane in the defect zone and its fixation, suturing of the wound, in which an individual titanium membrane that repeats the shape of the defect, including holes for filling the augmentation zone and holes for fixing screws, for the manufacture of which an X-ray examination of the jaw is preliminarily performed using a cone-beam computed tomography scanner, the data obtained in DICOM format are converted into .stl format and used in software providing for the reconstruction of the model of the lost volume of bone tissue of the alveolar process, create a 3D model of the defect zone and a 3D model of an individual meme apertured wound by 3D printing by laser sintering of a titanium dust produced individual membrane thickness 0.3 mm orifice, wherein the membrane is set augmentation overlapping zone, fix and filled autokostnoy shavings, mixed with artificial pictures xenografts in a ratio of 1: 1.

A computerized approach to creating an individual membrane makes it possible to accurately reproduce the anatomy of the jaw before a defect occurs, based on similar areas in the oral cavity in which teeth are present or by an average value. Thanks to this, you can achieve the best aesthetic results for patients.

In the 3Shape tool software, based on the volume of voxels (DICOM computed tomography data), the required bone surface area is created in .stl format.

The manufacturing technology of an individual titanium membrane in the form of a solid plate, including holes for filling the augmentation zone and holes for fixing screws, using 3D printing by laser sintering from titanium dust using a Concept Laser Mlabcusing 90 × 90 apparatus, Germany (SLS technology; AlexLou, Carol Grosvenor . "Selective lasers intering, birth of an industry") makes it possible to create it of any shape, width and height, based on the defect zone and the anatomical features of the zone in which bone augmentation and subsequent dental implantation will be performed.

The thickness of the titanium membrane is 0.3 mm and is optimal for ensuring high membrane strength and shape retention.

The membrane used is a completely milled structure and therefore there is no possibility of microbial invasion under the membrane. In this regard, there is no need to remove the membrane in case of partial exposure, in contrast to the mesh membrane.

The method is illustrated in FIG. 1-13, where:

in FIG. 1 - X-ray examination of the jaws using a cone-beam computed tomograph in DICOM format;

in FIG. 2 - a bone tissue surface area required for augmentation in .stl format;

in FIG. 3 - model of an individual membrane;

in FIG. 4 - pronounced vertical and horizontal atrophy of the alveolar ridge on the lower jaw on the right;

in FIG. 5 - section of the mucous membrane in the middle of the alveolar ridge

in FIG. 6 - skeletal bone tissue, perforations in the cortical plate.

in FIG. 7 - installation of the membrane in the augmentation zone.

in FIG. 8 - fixation of an individual membrane in the augmentation zone using titanium screws;

in FIG. 9 - introducing a mixture of bone materials through the corresponding holes in the membrane;

in FIG. 10 - the application of non-absorbable sutures;

in FIG. 11, 12 - removal of stitches in 10-14 days,

in FIG. 13 - postoperative 3D-CT.

The method is carried out, for example, as follows.

An x-ray examination of the jaw is carried out using a cone-beam computed tomograph in the DICOM format. On the obtained images (Fig. 1), the site 1 of the atrophied part of the alveolar process to be augmented is determined. Using the 3Shape tool software, based on the voxel volume, the required portion 2 of the atrophied part of the alveolar ridge is created in the .stl format (Fig. 2).

Model the lost volume of section 3 of bone tissue. Create a 3D model 3 of an individual membrane with holes 4 of rectangular shape 2-3 mm wide, 4-6 mm long in the amount of one or two for making osteoplastic material under the membrane and 5 holes for fixing screws with a diameter of 1.2-1.5 mm in the amount of 3-5 screws.

Model 3 of an individual membrane is sent to 3D printing, where a blank of 0.3 mm thickness is made from titanium dust by laser sintering, which is then processed and sent to a medical institution for surgery.

Immediately before the operation, the individual membrane is sterilized (cold sterilization, autoclaving).

The surgical stage begins with anesthesia. An incision 6 of the mucous membrane is made, the mucoperiosteal flap is exfoliated, and the flap is mobilized. Then bone skeletonization is performed, perforation 7 is performed in the cortical layer of the jaw bone.

The sterile membrane 8 is installed with the overlap of the augmentation zone, fixed with several titanium screws with a diameter of 1.2-1.5 mm and a length of 4 to 12 mm. The number of fixing elements is chosen taking into account the anatomy, bone density, membrane size at the laboratory stage. Typically, a secure fit can be achieved with 3-5 screws.

A mixture of 9 autocostal chips with artificial xenograft material is introduced in a 1: 1 ratio through the corresponding openings 4 in the membrane 8, which were previously modeled at the laboratory stage. Suture 10 is carried out with non-absorbable suture material supramide 5.0.

Sutures are removed after 10-14 days. Removal of the membrane 8 is carried out after 4-5 months, after which the volume of augmented bone tissue is assessed, a new 3D-KT examination 11 is performed, and the installation of dental implants in the area of the enlarged bone tissue is planned.

The method is confirmed by a clinical example.

Patient K., 57 years old, partial loss of teeth on the lower jaw, atrophy of the alveolar ridge, pronounced vertical and horizontal atrophy of the alveolar ridge on the lower jaw on the right (Fig. 4).

The patient underwent x-ray examination of the lower jaw using a cone-beam computed tomograph (Fig. 1). Using the 3Shape tool software, the image of the bone site for augmentation is made in .stl format.

A model of the lost volume of the bone tissue of the alveolar ridge crest was recreated, a 3D model of the defect zone and a 3D model of the individual membrane with the corresponding holes for making bone-plastic material and for fixing screws were created. Made 2 holes for making osteoplastic material and 3 holes for screws.

Using 3D printing by laser sintering from titanium dust with subsequent processing, a membrane in the form of a plate with a thickness of 0.3 mm with holes was repeated in advance, repeating the shape of the defect.

The sterile membrane is installed with the overlap of the augmentation zone and secured with three titanium screws. After the membrane was fixed, the augmentation zone was filled with a mixture of autostone chips and artificial xenograft material (Geistlich Bio-Oss Spongiosa, Geistlich Pharma) in a 1: 1 ratio. Autologous bone shavings were obtained from the patient intraoperatively from the retromolar region of the lower jaw on the right. Sutures were made with non-absorbable suture material supramide 5.0. Sutures were removed after 14 days. There were no postoperative complications. The membrane was removed after 4.5 months, the required volume of bone tissue was obtained. A postoperative 3D CT scan was performed (Fig. 13), a plan for the installation of dental implants in the area of the enlarged bone tissue was drawn up. Implants are installed in the correct orthopedic position.

According to the claimed method using individual titanium membranes, 20 patients were operated on.

In 17 patients, the postoperative period was uneventful, there were no complications. After removing the individual membrane, the required volume of bone tissue was obtained and dental implants were installed in the correct orthopedic position. In 3 patients in the postoperative period (from 2 to 6 weeks after surgery), a small exposure of the titanium membrane occurred due to deficiency of soft tissues (gums) and the presence of muscle cords. In these clinical cases, premature membrane removal was not performed. Patients were given detailed hygiene recommendations beyond the exposed portion of the membrane. In all 3 clinical cases, there was no microbial invasion under the titanium membrane. After 4-5 months after removal of the individual membrane, the required volume of bone tissue was obtained and dental implants were subsequently installed.

Thus, the use of a whole titanium membrane for bone augmentation solves the problem of the most frequent postoperative complication, namely, exposure of the membrane due to discrepancy of sutures or deficiency of soft tissues in the defect zone. When exposing collagen membranes or a titanium mesh during bone augmentation, it is necessary to remove the membrane, since microbial invasion under the membrane and bone material contamination inevitably occur.

The method provides restoration of the anatomy of the original bone tissue, the creation of an individual membrane of any complexity, reduction of operating time, does not require correction of the individual membrane during surgery, makes it possible to use temporary prostheses in the early postoperative period, improves aesthetic results, ensures the preservation of the shape of the membrane, does not require removal membrane in case of partial exposure, reduces the number of postoperative complications, improves aesthetic results.

Claims (1)

The method of augmentation of the atrophied part of the alveolar process of the jaw, including an incision in the area of the defect of the jaw, peeling of the mucoperiosteal flap, mobilization of the flap, skeletal bone tissue of the outer surface of the alveolar process, performing perforations in the cortical layer, filling the augmentation zone with a mixture of autologous bone chip, the installation of a titanium membrane in the defect zone and its fixation, wound closure, characterized in that an individual titanium membrane is installed, p the repeated defect form, including holes for filling the augmentation zone and holes for fixing screws, for the manufacture of which a preliminary x-ray examination of the jaw using a cone-beam computed tomograph is performed, the obtained data in the DICOM format are converted into the .stl format and used in the 3 Shape software for reconstructing the model of the lost volume of the bone tissue of the alveolar process, create a 3D model of the defect zone and a 3D model of an individual membrane with holes, using 3D echati by laser sintering of a titanium dust produced individual membrane 0.3 mm thick, with holes, wherein the membrane is assembled with overlapping area augmentation, fixed and filled autokostnoy shavings, mixed with artificial xenograft material in a ratio of 1: 1.

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