RU2320285C2 - Method for restoring alveolar jaw bone crest and periodontium tissues having reduced recovery potential - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves removing pathologically changed structures. Defect is filled with blood clot from jaw bone and/or periodontium ligament. Autologic vascular cellular fraction containing stem cells is transplanted into tissular defect region. The fraction contains fibroblast-like cells separated from fat and cleared from mature adipocytes without preliminary culturing.

EFFECT: accelerated recovery; enhanced effectiveness in forming new dentogingival attachment.

2 dwg

Description

The invention relates to medicine and can be used in surgical dentistry, periodontics and maxillofacial surgery, to restore the natural structure and function of the bones of the alveolar ridge and periodontal tissues with reduced regenerative potential.

As a result of chronic destruction of the bones of the alveolar ridge of the jaw and the supporting apparatus of the tooth, the regional blood flow worsens, the density of the remaining bone structures increases, and the size of the bone marrow compartment decreases. This leads to a deficiency of cells capable of differentiating into necessary cell lines during reparative regeneration. During recession of periodontal tissues, an avascular exposed and exposed to surface hypermineralization root surface acts as a substrate for constructing a new supporting apparatus of the tooth. The high prevalence of defects in the jaw bones and periodontal tissues, the development of pronounced soft tissue and skeletal deformities in the dentoalveolar region determine the urgency of high-quality medical rehabilitation of such patients.

In the surgical treatment of bone defects and periodontal tissues, various osteoplastic materials are used to stimulate osteogenesis in combination with a culture of diploid fibroblasts from human embryonic tissue (RU 2210352 C1, 08.20.03; RU 2231986 C1, 10.07.04), as well as with allofibroblasts cultivated on dura mater (Tumanov et al., 1998), which fill anatomical defects. However, the clinical and histological results after such interventions are extremely ambiguous: a nonfunctional scar forms, an overgrowth of the marginal epithelium and a lack of normal tooth-gingival attachment in the periodontal tissue healing zone are noted, excessive calcification with violation of the skeletal functions of the tissue, encapsulation of implant granules is noted in the replaced area of the jaw bone reactions to a foreign body are often observed, up to pyrogenic effects (Perova, 2005). Xenogenic materials are relatively slowly reconstructed in the defect zone, carry the danger of an immune conflict, the risk of transmission of animal infections to humans is not excluded.

A known method of restoring bone integrity (RU 2240135 C1, 11/20/2004), involving the use of a mammalian bone marrow cell culture containing osteogenesis precursor cells.

The method consists in the fact that cells of the stromal and lymphomacrophagic series of the bone marrow are cultured in an osteogenic induction medium until a monolayer culture is formed on an allogeneic demineralized bone matrix and a sponge from biodegradable material and introduced into the bone defect, achieving revascularization using a bone autograft.

The disadvantages of this method are the difficult preparation of a bone marrow transplant for wide clinical use, the high risk of complications in the donor area, the long term of treatment and the onset of a beneficial result, the potential risk of spontaneous oncogenetic transformation during transplantation of cultured “adult” human stem cells (Singh et al 2004) , the risk of genetic instability due to the appearance of hybrid cells with a polyploid karyotype as a result of culture passaging, virus transmission, progression sc diseases by shutting down the cells of the cell cycle - apoptosis (Ogle et al 2005).

The objective of the present invention is to ensure the reliability of treatment results, eliminating the risk of developing neoplastic processes, increasing the degree of medical and social rehabilitation, reducing treatment time.

The essence of the invention consists in introducing into the bone defect zone of the jaw alveolar ridge or periodontal tissues before implantation and a biocompatible barrier membrane (adjuvant condition for regeneration), an autologous vascular-cell fraction containing mesenchymal stem cells isolated from adipose tissue, purified from mature adi having fibroblast-like morphology, without preliminary cultivation, for the restoration of bone and periodontal tissues, which during a long pathological This process has a reduced regenerative potential. Moreover, during recession of periodontal tissues, instead of implanting the membrane, the exposed surface of the tooth root is preliminarily covered with a palatine subepithelial connective tissue flap.

The technical result of the invention is to compensate for the deficiency of progenitor cells in reduced bone and periodontal tissues due to the morphogenetic abilities of autologous pluripotent cells that differentiate into the desired cellular phenotype in the tissue microenvironment; an increase in the rate of osteogenesis and the formation of a new periodontal attachment corresponding to a natural sample, which allows to qualitatively increase the effectiveness of treatment by an average of 93%; reduction of almost 3 times the rehabilitation period; reliable relapse prevention; a twofold reduction in the risk of deformations of the dentoalveolar region and bones of the facial skeleton. In the remote observation period, no cases of neoplastic processes were detected.

The method is as follows. A bone defect in the alveolar crest of the jaw or supporting tooth tissues is subjected to curettage to remove pathologically altered structures; during recession of periodontal tissues, the exposed root surface is treated with a solution of citric acid (pH 1.0) for demineralization. Defects are filled with blood obtained from the bone marrow spaces and the vital periodontal ligament. Specially prepared according to the method of P. Zuk et al. Are transplanted into a blood clot. (2002) an autologous vascular cell fraction containing mesenchymal stem cells — fibroblast-like cells isolated from adipose tissue and purified from mature adipocytes without prior cultivation. A biocompatible non-resorbable barrier membrane is implanted on top of the regeneration focus, and, upon elimination of tissue recession, a subepithelial connective tissue autologous palatine flap. The surgical wound is sutured and covered with a periodontal dressing (such as VocoPac) for 2-3 days.

The following examples illustrate the present invention. The method was tested in an experiment on 2 guinea pigs, in a clinic - for 18 patients (38 defects in bone and periodontal tissues), including in surgical dentistry - for 4 patients, in periodontology - for 11 patients, maxillofacial surgery - for 3 patients .

An animal experiment showed a significant acceleration of the primary healing process of the surgical wound when using an autologous vascular-cell fraction (Fig. 1a) containing fibroblast-like cells (FB), compared with the control (conventional healing of the defect). Noteworthy is a significant (almost 5-fold) increase in the number of actively working cells in the regeneration zone. The formation of the spongy structure of the osteoid matrix was noted already in the 1st week after the operation, while in the control - by the end of the 2nd week. The surface of the newly formed numerous bone trabeculae (MK-young bone) was covered with many active osteoblasts (OB), which give a positive reaction to alkaline phosphatase, walled osteocytes (OC) were already detected in the thickness of the osteoid matrix, the intertrabular spaces were filled with young myeloid tissue (MT) with thin-walled blood vessels of the sinusoidal type (CS) (figb). After 4 weeks in the test group, the artificially formed bone defects of the animal were completely filled with bone with all the characteristic histological signs of mature structures, while in the control at this time only the stage of replacement of the primary osteoid matrix with coarse bone was determined.

Clinical results showed that the healing rate of the surgical wound increased on average by 2 times. Already by the 6th day, the sutures lost their fixation properties due to the rapid epithelization of the wound, while in the control they were removed on the 12-15th day. The exposure of the barrier membrane did not require more than 10 days in situ due to the formation of a submembrane tissue with clearly differentiated structures by this time. In the control group, a new granulation tissue was formed during these periods, and the regenerate volume was significantly higher in the test group and fulfilled the defect volume completely set by the membrane. In the near term of observation, it was noted that the tissue profile formed in the defect zone is less susceptible to retraction (shrinkage) processes, as well as connective tissue autograft tissue during the elimination of periodontal recession - within 10-15% compared to the control, where the retraction of the newly formed tissue amounted to 25 % The identified trend was also observed in assessing long-term results up to 1 year: the level of residual recession of periodontal tissues compared with the control group was 1.3 mm ± 0.1 and 3.2 mm ± 1.7, respectively; the volume of the submembrane useful tissue profile during restoration of the tooth support apparatus was 93% compared to 65% in the control, atrophy of the bone crest after tooth extraction (about 20% compared to the control, where up to 40-50% is noted).

Using the method allowed to significantly reduce the time (almost 3 times) and increase the effectiveness of treatment of patients with severe destructive processes in the dentoalveolar region and periodontal tissues by an average of 93% (in the control, up to 70%).

Example 1. Patient D., 25 years old, turned to the Center for Periodontology and Dental Implantation in Krasnodar with a diagnosis of generalized recession of periodontal tissues in the area of premolars, canines and lateral incisors of the upper and lower jaws, Miller Grade II. Complaints of exposure of the roots of the teeth (figa), noticed since 19 years, the appearance of sensitivity of exposed surfaces to temperature stimuli over the past three years, an aesthetic defect, fear of tooth loss. On the vestibular side, the loss of marginal periodontium is actively progressing at an average rate of about 1 mm per year.

After examining the patient, making diagnostic models of the jaw, acrylic palatine plate and obtaining an autologous vascular-cell fraction, surgical treatment was performed. Under conduction anesthesia Ultracain-forte 1.8 ml in the area of tissue recession of premolars and canine on the lower jaw on the left, a split flap is formed to the level of the alveolar gum. Bilaterally to the defect, supraperiosteal envelopes are excluded, excluding vertical cuts. The root surfaces were cleaned of dental deposits with an ultrasonic apparatus, demineralized with a 3% citric acid solution at pH 1.0 for 1 min, followed by washing with sterile saline. In the donor zone, from the area of the hard palate under Sol infiltration anesthesia. Lidocaini 0.5% 3 ml. Subepithelial connective tissue was taken with a perioste size corresponding to the area of the recipient zone - 24 mm X 12 mm. The wound in the donor zone after hemostasis is sutured with cross tightening sutures. An autograft is placed in a formed envelope with a periosteum to the defect. In the space between the exposed root surfaces and the connective tissue, a blood clot is formed from the preserved periodontal-ligamentous and bone structures, into which an autologous vascular-cell fraction is additionally introduced. The graft is fixed with interrupted sutures placed in the interdental spaces, the epithelial flap is mobilized over the graft and fixed with cross and bypass sutures without tension. The surgical field in the recipient area is covered with VocoPac periodontal dressing for two days. The donor area is protected by an acrylic plate.

On the 3rd day in the field of surgical intervention, slight swelling and discomfort were noted, there were no general reactions. The tissues are in a state of healing, the seams are stable. On the 7th day there were no complaints, the sutures were removed due to wound epithelization in the donor and recipient areas, the transplanted connective tissue flap in the state of formation of a new periodontal attachment. The elimination of symptoms of tooth hypersensitivity was noted. On the 14th day retraction of the transplanted tissue was observed within 10% of the transplanted volume.

After 4 months, the symptoms of periodontal tissue recession were completely eliminated, the bare root surfaces were closed due to the formation of a strong tooth-gingival attachment, the probe depth was 0.8 mm, the width of the attached gum increased from 2.3 mm to 11.7 mm.

After 12 months, the patient has no complaints, the condition of the periodontal tissues in the surgical area is stable, the probe depth is 0.6 mm, the width of the attached gum is 11 mm (Fig.2b). The values of the grafted tissue retraction parameters did not change in comparison with those after 4 months.

Example 2. Patient E., 37 years old, turned to the Center for Periodontology and Dental Implantation in Krasnodar with a diagnosis of chronic generalized periodontitis with developed loss of supporting tissues; periodontal abscess of 16 teeth, periodontal loss of up to 95%. Objective examination data: the gums are swollen, hyperemic, bleed when touched, the average probing depth is 5.5 mm with a loss of gingival attachment of about 7 mm, tooth mobility of the 2nd degree, the defeat of the furcations of molars of the upper jaw F2-F3. After initial therapy and preparation of an autologous vascular-cell fraction, quadrant surgical treatment was performed.

Under palatinal, incisive and infiltration anesthesia of Ubistesin 4% - 3.6 ml, mucoperiosteal flaps in the areas of 12, 13, 14, 15, 16 and 17 teeth are exfoliated. Removed 16 tooth. Periodontal pockets and holes of the removed 16 tooth were cured, teeth root surfaces were cleaned of dental deposits and infected cement, periodontal tissue defect and hole of the 16 tooth were treated with 0.1% sodium hypochlorite solution for 10 minutes, the flaps were de-epithelized. A blood clot was obtained from the surrounding defect and the well of the removed tooth of the bone tissue and the preserved periodontal ligament, into which an autologous vascular-cell fraction containing mulpotent fibroblast-like cells was transplanted. Ecoflon non-resorbable polytetrafluoroethylene membrane was implanted on top of the defect thus filled, the flaps were put in place, the wound was sutured with mattress, cross and interrupted sutures. The surgical field is covered with VocoPac periodontal dressing for two days.

On the 3rd day in the area of the attached gum, there is a slight swelling and discomfort during palpation, fibrinous plaque along the edge of the surgical wound, and slight hyperemia of the gum. Seams are wealthy, stability in the defect zone is preserved. On the 7th day, the patient showed no complaints, palpation of the tissues was painless, the sutures and barrier membranes were removed, the defect zone was filled with young granulation tissue, the beginning of the formation of gingival attachment was noted in depth. There are no complaints on the 14th day, the regenerate tissue is densified, pale pink, does not bleed when probed, a complete fusion of the mucoperiosteal flap with the regenerate tissue is observed, tooth-gingival attachment is actively formed - the probe depth is 2.5 mm. Shrinkage of the tissue profile within 5%.

After 4 months, periodontal pockets are completely absent, the probe depth is up to 1 mm, the shrinkage of regenerated tissues in the molar area is within 10%, in the area of other teeth - up to 5%, the total increase in clinical attachment was 5.8 mm. In the area of 12, 13, 14 teeth, interdental gingival papillae are actively formed. After removal of the temporary tire in the region of the 17 tooth, mobility of the first degree is noted, in the area of other teeth it is absent.

After 12 months, there were no complaints, the color and consistency of periodontal tissues were normal, there was no increase in attachment loss, periodontal pockets were absent, tooth mobility was physiological. Radiologically, the appearance of a shadow of new dense structures in the inter-root zones, a periodontal gap of normal size, is noted. A titanium dental implant is installed in the region of the removed 16 tooth in combination with the movement of the maxillary sinus bottom; primary implant stabilization is achieved in the dense bone structures of the subantral region.

After 24 months, the patient does not complain, the periglossal and near implant tissues are pale pink, dense, the probe depth of the teeth and the implant does not exceed 1 mm, tooth mobility is absent, the implant is adequately loaded and fully functioning for 8 months, osseointegrated over the entire height of the intraosseous part . A significant increase in the dense structures of the alveolar ridge of the jaw in the treated area and the processes of remodeling under the load of near-implant bone structures are noted radiologically.

Thus, the results demonstrate the feasibility of applying the proposed method for restoring the bone of the jaw alveolar ridge and periodontal tissues with reduced regenerative potential in order to achieve a natural structural and functional sample and maintain a healthy state in the region of exposure for a long time.

The method is easily reproducible, does not require significant material costs, is economical, can significantly reduce the treatment time, ensure the reliability of the results at a qualitatively new level and can be applied in practical medicine.

Bibliography

1. Perova M.D. Periodontal tissues: norm, pathology, recovery paths. - M .: Triad - 2005, 312 p.

2. Tumanov V.A., Dmitrieva L.A., Runova G.S., Rudneva E.V. The use of allofibroblast culture in the complex treatment of periodontal diseases. Science - practice: Proceedings of the scientific session of the Central Research Institute of Scientific Research, dedicated. 35th anniversary of the institute. - M., 1998 .-- S. 164-165.

3. Singh S.K., Hawkins S., Clarke I.D. et al. Identification of human brain tumor initiating cells. Nature 2004; 432: 396-401.

4. Ogle B.M., Cascalho M., Platt J.L. Biological implications of cell fusion. Nat. Rev. Mol. Cell. Biol. 2005; 6 (7): 567-575.

5. Zuk P.A., Zhu M., Ashjian P. et al. Human adipose tissue is source of multipotent stem cells. Mol. Biol. Cell 2002; 13: 4279-4295.

Claims (1)

A method of restoring a bone of the alveolar crest of the jaw and periodontal tissues with reduced regenerative potential, including removing pathologically altered structures, filling a defect with a blood clot from the jaw bone and / or periodontal ligament, characterized in that an autologous vascular-cell fraction is transplanted into the region of the tissue defect containing stem cells - fibroblast-like cells isolated from adipose tissue and purified from mature adipocytes, without prior cultivation Nia, the periodontal tissue recession when exposed dental root surface previously coated palatal subepithelial connective tissue graft.

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