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Techniques and methods for the design of tooth and jaw systems with artificial implants are analyzed. The mathematical model is based on data of precision measurements of the entire complement of biometric characteristics that determines the properties of a biomechanical system. The calculations presented here make it possible to predict complications that may arise in the process of implanting dentures.

We compared the morphology and differentiation capacity of human stromal cells derived from bone marrow (BMSC), adipose tissue (ATSC), hair follicle dermal papilla (DPC) and dermal fibroblasts (DFb). All cells have fibroblast-like morphology. ATSC and DPC cells expressed stem cell the surface markers CD105, CD49d, and STRO-1, which were revealed immunocytochemically. CD49d was not found on BMSC. The low expression of CD49d and STRO-1 was registered in the DFb population. ATSC, BMSC, and DPC have similar capacities for adipo- and osteogenic differentiation. These cells, cultured in appropriate induction media, alter the phenotype and synthesize specific proteins. However, the expression of differentiation in the DPC population is lower than in ATSC and BMSC cultures. We propose that these cell populations have primitive progenitor cells with properties of mesenchymal stem cells.

Three groups of biostable composite materials were studied. The initial binder polymers (polymethylmethacrylate, polyamide-12, superhigh-molecular-weight polyethylene) and hydroxyapatite-containing composites on the basis of these polymers were tested. Biostable polymers, including those containing hydroxyapatite, were nontoxic for fibroblasts and mesenchymal stem cells: the adhesion parameters for these cells were maximum for polyamide-12 and superhigh-molecular-weight polyethylene and did not depend on the presence of hydroxyapatite. Cell adhesion to “ pure” polymethylmethacrylate was significantly lower than to other composites, but increased after integration of hydroxyapatite. The efficiency of proliferation of fibroblast and mesenchymal stem cell on the surface of polyamide-12 and superhigh-molecular-weight polyethylene was maximum and did not depend on the presence of hydroxyapatite. The efficiency of cell proliferation on the surface of “pure” polymethylmethacrylate was low, but increased significantly if it was combined with hydroxyapatite, particularly in areas of mineral particles accumulation. It seems that the presence of high amounts of hydroxyapatite in polymethylmethacrylate samples promotes cell adhesion and proliferation.

Parathyroidectomy increases the degree of(45)Ca fluctuations between the blood and mineralized tissues (bones and teeth) in rats, which is associated with a decrease in 14C-glycine incorporation into bone proteins. Disturbances in Ca(2+)metabolism and transport during hyperparathyroidism are partly prevented by parathyroidectomy. It is mainly related to variations in the interaction of parathyroid hormone, calcitonin, 1.25(OH)2D3, and other bioactive substances, but not to initiation of mineralization with protein matrixes.

Chemical modification of HA with PAA and PVP solutions prior to PMMA/HA composite synthesis gave rise to a significant improvement of the bending and impact strength as well as a hardness and emollescence temperature of the final product. Polymer-polymer complexes, formed as a result of chemical interaction of non-reacted (with HA calcium ions) carboxyl group of PAA with PVP at the interface of HA with PMMA, play a key role in this improvement. Using IR spectroscopy and X-ray photoelectron spectroscopy, it was shown that all components of PMMA/HA composite can be linked together either by ionic bonds or by hydrogen bonding. This significantly enhances the mechanical properties of such bioactive polymer systems, and their functionality as an implant material.

We have investigated the biocompatibility of calcium phosphate coatings deposited by pulsed laser ablation from hydroxyapatite (HA) targets onto polyethylene and Teflon substrates. It was found that the cell density, attachment, and morphology of primary rat calvaria osteoblasts were influenced by both the original polymer and by the nature of the apatite coatings. HA coatings on Teflon were found to have higher biocompatibility in terms of cell adhesion and spreading. In vivo studies of bone response to coatings deposited by KrF excimer and CO2 lasers on commercial Ti6A14V alloy implants show that both deposition techniques suppress fibrous tissue formation and promote osteogenesis. © 1998 Society of Photo-Optical Instrumentation Engineers.

In experiment on rats in the immunodeficiency the use of recombinant epidermal growth factor was substantiated that let to speed up reparative regeneration at concentration 500 ppb/l drinking water.

Reconstructive surgery often collides with complicated task of defect recovery in the situation of deficit of maxillofacial skeleton tissues, that leads to necessary search of accessible cells source with osteogenic potentials and proper substrate for cell transplantation. In the study the regeneratory potential of stromal cells of adipose tissue was tested in the rabbit model of mandible through angle defect. Cells of allogenic and autologic nature stimulated reparative osteogenesis but their influence upon bone matrix maturation was different. When the construction with allogenic cells was transplanted reaction of its rejection was not detected on histological level.

In experiment on 12 Chinchilla rabbits dynamics of reparative regeneration was studied at the terms 2 and 4 months. Bone defect in mandible corner was closed by osteoplastic material Gapkol which was covered from inside by allogenic or autologic stem cells received from rabbit adipose tissue. The results of the ray tracing methods of study were verified by SEM and histological methods.

In experiment on rabbits by histomorphometric method it was shown that after the use during 4 months of titanium plate with the culture of marrow mesenchymal stromal cells there happened full infill of mandible defect by lamellar bone tissue. In control group (titanium plate with inactivated culture of cells) the defect was replaced by regenerate, the most part of it was rough fibrous connective tissue. In experimental group in the central parts of the defect regenerate were characterized by bigger weight of lamellar bone matrix if compared with the peripheral parts of the defect that testified to higher level of its differentiation. Use of stem cells on titanium carrier led in 4 months experiment to full infill of jaw defect by lamellar bone tissue.

With the help of flow cytometry it was shown that for patients with hypergic inflammatory process in maxillofacial region the reduction of lymphocytes relative number was typical as well as their absolute number reduction. Direct and very strong correlation was established between absolute lymphocytes number in peripheral blood and absolute number of CD3 and CD4 lymphocytes subpopulations by correlation analyses. The reduction of absolute lymphocytes number in peripheral blood let speak with more probability about the reduction of the number of CD3 and CD4 lymphocytes subpopulations and diagnose secondary immune deficit.

Aim of the study was substantiation in experiments on rabbit ramus mandibulae of the method of mesenchymal stem cells (MSC) on the carrier from titanium and gold alloy for reparative osteogenesis enforcement. There was shown stimulating action of the MSC implantation in the bone wound upon reparative osteogenesis at the terms from 1 to 4 months. It was concluded that implants from titanium and gold alloy may be used as carrier for MSC for bone tissue reparative regeneration stimulation.

We compared the morphology and differentiation characteristics of the human cells from bone marrow, adipose tissue, hair papilla and skin dermis. All cell types showed fibroblastic morphology. Immunofluorescent analysis showed that adipose tissue derived stem cells (ADAS) and hair papilla cells (HPC) expressed CD105, CD49d and STRO-1, bone marrow mesenchymal stem cells (BMSC) were absent for CD49, dermal fibroblasts (DFb) expressed CD49 and STRO-1 at low level. Populations of ADAS, BMSC and HPC had similar capacities to lipid and bone differentiation. Following exposure to appropriate induction stimuli, these cells changed phenotype and expressed specific cell markers. However, the rate and extent of HPC differentiation were lower in comparison with populations of ADAS and BMSC. We propose that all investigated cell populations contain primitive progenitor cells with mesenchymal stem cell properties.

Dysbiotic shifts in intestinal and integumentary microflora were studied in 10 test-subjectes during 7-day "dry" immersion. Essentially every test-subject reduced significantly fecal lactoflora and developed dysbiotic shifts in the microbial landscape of various types of integument. Pharyngeal microflora was analyzed in 22 normal volunteers for 7-day "dry" immersion. Two probiotic preparations were administered to prevent pharyngeal dysbiosis: peroral dry lactobacterin and topical collagen-immobilized lactobacterin. The peroral probiotic stimulated growth of pharyngeal opportunistic pathogens preventing translocations of the intestinal microflora. The topical probiotic, on the opposite, reduced the content of opportunistic pathogens in the throat; however, it provoked gastrointestinal dysbiosis. It appears that the most effective prophylaxis of pharyngeal dysbiosis can be reached by prescription of both topical and peroral probiotics.

Biorhythms with higher levels of activity of sorbitol dehydrogenase and lactate dehydrogenase in blood plasma, specific activity of sorbitol dehydrogenase, lactate dehydrogenase, and malate dehydrogenase in the liver, and body weight of rats were more pronounced in the spring-summer period than in the autumn-winter period. These specific features were revealed in animals feeding a normal diet or food with 54 and 27% sugar substitute sorbitol. However, specific activity of glucose-6-phosphate dehydrogenase in the liver was higher in the autumn-winter period. Activity of sorbitol dehydrogenase in blood plasma increased by tens of times due to induction of sorbitol synthesis (substrate) in the liver. Sugar substitute xylitol is structurally similar to sorbitol, but is not the substrate for sorbitol dehydrogenase. However, the effect of xylitol on activities of lactate dehydrogenase, malate dehydrogenase, and glucose-6-phosphate dehydrogenase in the spring-summer period was similar to that of sorbitol.

Histamine releasing and immunomodulating activity of the following dental restorative materials (DRM) - Prizmafil, Filtek Z250, XRV Herculite Prodigy, Glasiosite, Te-Econol, Valux Plus, Polofil Supra were studied. It was shown that DRM under study as a rule did not possess the ability to release histamine (H) from human blood basophile (BB) excluding Filtek Z250 which release H from BB in patients with allergy and sound donors. The studied DRM implanted under mouse skin were able to modulate immune response to the allergen, at that some of them increased antibodies of IgE-class forming and other suppressed immune response caused by IgG-antibody forming. Received data have certain significance in the scheme of safety evaluation and individual assessment of DRM having acceptable biocompatibility for specific patient.

In rat experiments the ability of noncollagen bone proteins (NCBP) in the composition of osteoplactic modified material Gapkol (not tanned in formalin and subjected to vacuum extraction) to increase bone reparation in comparison with traditional Gapkol was studied. Quantitative evaluation was performed on rat parietal bone and qualitative evaluation was performed on rat mandible. It was shown that Gapkol with NCBP (not tanned in formalin and subjected to vacuum extraction) increased reparative osteogenesis.

Different types of dental materials (DM) were studied for their capacity to release histamine in vitro from basophils of whole blood of allergic patients and healthy donors using automated and computerized glass fiber-based leukocyte histamine release test (LHRT). It was shown that some types of DM possessed ability to release histamine from basophils and some didn't. There were no differences in histamine releaseability from basophils obtained from allergic patients and healthy donors. LHRT gives opportunity to recognize of DM possessing high or low histamine releaseability as well as to detect individual sensitivity to different DM. Thus, LHRT can be used for preliminary assessment of DM for their biocompatibility and also for individual selection of suitable DM for particular patient to avoid unwanted side effects.

Four groups of 1-month-old rats were fed with standard diet (SD) for a month, 46% SD + 54% sorbitol, 54% saccharose or 27% sorbitol + 27% saccharose. Fed with 54% sorbitol and with 27% sorbitol + 27% saccharose differed from rats given 54% saccharose and 100% SD (they were thin, had hyperreaction to light, diarrhea). Liver mass in all the tests in autumn and winter (AuWi) is lower than in spring and summer (SpSu). It is lower in 54% sorbitol, higher in 27% sorbitol + 27% saccharose, the highest in 54% saccharose and 100% SD. Specific activity (SA) of lactate dehydrogenase (LDG) is higher, glucose-6-phosphate dehydrogenase (G-6-PDG) is lower in SpSu than in AuWi in 4 diets. In 54% sorbitol and 27% sorbitol + 27% saccharose SA of LDG, G-6-PDG and succinate dehydrogenase (SDG) is not higher than in 100 SD. SA of SDG and LDG in SpSu is higher than in AuWi, G-6-PDG is lower in SpSu. SA of these three enzymes is not higher in 54% sorbitol than in 100% SD in contrast to 4-fold rise of SA of sorbitol dehydrogenase. Biorhythms of enzyme SA reflect the results of interaction of adaptive molecular mechanisms of the body, including genetic ones, with changing environment.

We studied pharyngeal microflora in 22 healthy volunteers after 7-day dry immersion. For prophylactic pharyngeal dysbiosis, we used two probiotic drugs: oral -- "lactobacterin dry" and local --"lactobacterin immobilized on collagen". Administration of oral probiotic was accompanied with growth of pharyngeal opportunistic microflora preventing translocation of intestinal microflora. Local probiotic, on the contrary, decreased opportunistic microflora in the pharynx, but was associated with gastrointestinal dysbiosis. It is evident that combined use of topic and oral probiotic provides maximal effective prophylaxis of pharyngeal dysbiosis.

One-month rats were randomized to a diet containing sorbitol (SOR) (54%), saccharose (SACCH) (54%) or that containing SOR (27%) and SACCH (27%). They were kept on the diets for 1 or 3 months. At the age of 2 and 4 months, the rats were returned to the routine diet of a vivarium. The experiments were terminated when the rats were aged 2, 4, and 7 months. In all seasons, the monthly diets containing 27% and 54% of SOR increased the serum activity of sortibol dehydrogenase (SDH) by several and tens of times. The 3-month diet produced the same effect. It suddenly turned out that the 54% SACCH diet also increased SDH activity, but to a lesser extent than a combination of 27 SOR and 27% SACCH, and by tens of times less than the 54% SOR diet. Comparison of three diets showed the same relationship between the increases in SDH activity in the liver. With excess dietary SOR, a very high increase was first found in serum and hepatic SOD activity by an induction mechanism.

In experimental study on 4 mongrel 4-5 year old dogs under intravenous anesthesia (rometar) after turning back of mucous-periosteum flap and forming artificial defects of hard tissues in the upper third of a dental root the defects were filled with glass-ionomer cement (Ketac-molar, 3M-Espe), composite light cured material (Heliomolar flow, Ivoclar-Vivadent), amalgam with high silver content (Amalcap Plus regular non-Gamma-2, Ivoclar-Vivadent) or with material for dental root perforation closure (PRO-Poot mta, Dentsply). It was found that parodontium reacted to these filling materials by inflammation. The glass-ionomer cement and material for dental root perforation closure had lesser effect on parodontium in comparison with composite and amalgam.

Four samples of dental materials (DM) estd for root canal filling, Septodent (S), Zinkoxide (Z), Foredent (F) and Cialite Regular (CR), were studied for their ability in vitro to release histamine (HR) employing the computerized fiber glass based histamine release assay using whole blood from allergic patients and healthy donors. It was found that F induced high and S low levels of HR from blood basophils from both allergic and non-allergic subjects. Z and CR did not induce HR from blood basophils similar to the negative control. The HR assay may be a useful method for preliminary investigation of DM employed for root canal fillings for safety as well as for selection of specific DM for individual patients.

In spite of the complications after expander use the advantages of local plastics predetermine constant return to the method. Systemic use of hypoxic training produces stimulating effect on the skin microcirculation and can be used widely in clinical surgical practice in cases of local plastic operations to prevent possible complications reducing consequences of blood supply disturbance and tissue oxygen provision. The method of hypoxic adaptation let us receive as non-medicamentous mean to prepare for shorter period of time more vital flap.

We studied concentration of histamine (Hs), serotonin (St) and catecholamines (CA) in the cells and plasma of venous and capillary blood of 466 patients with bronchial asthma (BA) and 40 controls free of BA. It was found that blood cells sorb, secret Hs, St and CA and participate in exchange of Hs, St and CA between tissues and blood. Contents of Hs, St and CA in BA patients is increased but CA decreased in the cells and plasma of capillary blood. Such distribution between Hs and CA can be explained by changed activity of histidindecarboxilase necessary for histamine synthesis. Capillarovenous difference by Hs, St and CA detected in the control group was also found in BA, being more pronounced in exogenic BA. It is suggested that BA patients have disturbed tissue-blood barrier and systemic alterations of synthesis and utilization of biogenic amines in blood of BA patients.

Systemic immunity was studied in patients with chronic generalized parodontitis. This group of patients had distinct changes in immunologic system: depression of T- and stimulation of B-cellular immunity without accumulation of plasma cells and initiation of effective humoral response. Increased peripheral blood number of lymphocytes expressing induction of apoptosis CD95 receptors and ligand for this receptor CD95L (Fas-L) can lead to intensification of lymphocyte apoptosis and may be the reason for T-cell deficit development. The results of the study confirm the important role of immune system disturbances in pathogenesis of chronic generalized parodontitis.

Periodontal dressing consisting of collagen and Lactobacillus casei 37 cell suspension (cell concentration 108 cells/ml) was created and used in combined treatment of patients with chronic generalized parodontitis. Efficacy of the developed isolation was explained by a considerable decrease of the number and frequency of isolation of aggressive microbial representatives (pigment synthesizing Bacteroids, Actinomyces and Str. intermedius) in periodontal pockets and also Fungus (Candida albicans). This periodontal dressing provided remission up to 10-12 months.

The histamine-releasing activity of acrylic plastics (ftorax, stomacryl, ethacryl) used for denture making and maxillofacial prostheses was studied by automated and computer-aided fiber glass method for evaluating histamine release from whole blood basophils. The results indicate that some plastics made by the thermo-polymerization method (for example, ethacryl) are characterized by higher histamine-releasing activity than the plastics made by polymerization using superhigh frequency electromagnetic energy. The method is recommended for preliminary screening of new polymers intended for dentistry and for individual selection of materials with consideration for their safety and strength characteristics.

Mathematical simulation, estimation, and evaluation of stress-deformed status of bone tissue under the roots of functionally loaded mandibular abutment teeth after their depulpation were carried out. The resultant mathematical model, realized in the SPLEN-K system, is the key stage in the development and subsequent clinical application of automated diagnosis and consultation complex for patients with dentition defects.

The experimental study of the properties of the collagen- and hydroxyapatite-containing osteoplastic material HAPKOL-I by bone marrow hemopoiesis was made in comparison with existing material HAPKOL. HAPKOL-I is a working name of the material consisting of HAPKOL and composition of non-collagen bone proteins produced from xenogenic bone material. Long-term cultures of bone marrow from mice (C57B1/6xCBA)F1 of dexter type were used. Cultivation time was 7, 14, 21 and 28 days. Intensity of hemopoietic processes was assessed on the samples; absolute count of stromal and hemopoietic cells on the membrane was calculated. It was found that in long-term cultures of the bone marrow stromal and hemopoietic cells develop on the materials HAPKOL and HAPKOL-I, processes of formation of hemopoietic microenvironment provide normal hemopoiesis. On both materials there was a gradual increase of cell counts, a rise in the number of stromal and a fall in the number of hemopoietic cells. More intensive hemopoiesis on the material containing non-collagen bone proteins may be due to this factor.

The mechanisms of lip wound healing after bilateral crossing of the inferior alveolar nerve (IAN) were studied on Chinchilla rabbits in 3 experimental series, 6 animals per series. In group 1 bilateral crossing of IAN was carried out, in group 2 bilateral crossing of IAN was paralleled by removal of a mucous flap in the middle of the lower lip, and in group 3 the same wound as in group 2 was created, after which the wounds in this group were daily treated with a special ointment and a single injection of lidocaine (1% solution) under the wound. The nerve crossing led to development of ulcer on the lip with degenerative changes in the vascular walls, destruction of nerve fibers, and fragmentation of some axial cylinders. Crossing of IAN simultaneously with removal of the lower lip flap led to more severe degenerative changes in the tissue. Daily treatment of the lip with the ointment and lidocaine blocking normalized wound healing. A possible mechanism of the changes observed is discussed.

Tissue reactions to active modified composite material were studied in experiments on Chinchilla rabbits. In the first series of experiments plates from composite material were implanted: polymethylmethacrylate (PMMA) plates were used in group 1, PMMA composition with hydroxyapatite (HAP) in group 2, and PMMA composition with HAP modified by polyacrylic acid in group 3. The content of HAP in each group was 30% by weight. Implantation of plates from pure PMMA induced atrophic processes with formation of connective tissue capsule at the site of implantation. In the second series of experiments the manifestations of inflammatory reactions in the bone and adjacent tissues, caused by HAP release into tissue, were observed, which were paralleled by activation of bone formation, which sometimes acquired the pattern of a hyperproductive reaction. PMMA/HAP composite modified by chemical bond proved to be the most effective: its implantation caused no manifest pathological reactions and inflammatory infiltration; no intraosseous deposition of crystals were detected. Intensive osteogenesis round the implanted plate was observed.