Studied 62 teeth removed for medical reasons in 54 adults (32 men and 22 women) of different ages to determine age-related changes in the root tips of teeth.Were used methods of odontoscope, x-ray examination, and prepared and studied thin sections of tooth roots. It is established that with age, in the absence of resorption of the apex and gipertireoze in the apex of the tooth root, in adults there is a reduction of the diameter of the root canal in the apical third of the root, due to the formation of secondary dentine, as well as a slight thickening of the cement in the region of apical hole. Thus, increases with age the distance between apical constriction, apical foramen and the radiographic apex of the tooth root. People young and middle age obliteration of root canal teeth are studied according to x-rays does not occur. In elderly and senile obliteration of the root canals of the teeth in the area of the tops are marked at 75% and 79%, respectively, but in thin sections of the roots, which according to x-ray examination is determined by the obliteration of the cavity of the tooth root, the channels typically have a lumen, that is, they are passable for endodontic instruments.

Smear layer is created by rotary and hand instrumentation. This layer closes dentin tubules and reduces the effect of irrigating solutions, the quality of obturation and outcome of endodontic treatment. The aim of this study was to assess the quality of removal the smear layer with the traditional way of chemo-mechanical instrumentation and with addition of a new instrument XP-endo Finisher. This in vitro study included 40 single-rooted extracted premolars, аnd 20 molars which were separated into 3 groups - «A», «B» and «С». All groups were preparing using NiTi instruments ProFile, NaOCl 3%, EDTA 17%. In groups «B» and «С» the smear layer was removed using XP-endo Finisher. In SEM we received results based on Hulsmann criteria in each canal third (coronal, middle and apical), which were analyzed. Application of XP-endo Finisher removed the smear layer from root canal walls in all segments.

The aim of the study was a comparative analysis of a number of factors of nonspecific and specific immune defense in the oral cavity in patients with rheumatoid arthritis (RA). In a blindly controlled study, 75 volunteers of both sexes aged 35-44 years, equally divided into three groups, participated. In group 1 there were patients with newly diagnosed RA, in group 2 - patients with chronic generalized periodontitis and multiple caries of teeth without concomitant general somatic pathology, in group 3 - practically healthy patients with CFR<10. The concentration of lysozyme, neopterin, γ-interferon, neutrophil elastase, thiol status and IL-4 was studied in the oral fluid. It was revealed that at 100% prevalence of dental caries and inflammatory periodontal diseases in RA patients there were hypo salivation phenomena, a decrease in the concentration in oral liquid (OL) lysozyme, IL-4 and thiol status. On the contrary, there was an increase in the levels of neopterin, γ-interferon and elastase. It was concluded that the activity of local cellular and humoral immunity in the oral cavity decreased in patients with RA, in particular, the increase in proteolytic activity of OL and the decrease in its antioxidant protection. Recommended preventive and therapeutic dental activities in patients with RA primarily focus on stimulating salivation and minimizing the cytotoxic immune response. In the second turn - to reduce the proteolytic activity of mixed saliva and increase the anti-oxidant protection of periodontal and mucosal tissues.

In experiments with 390 outbred male rats that were: 1) on the cariogenic diet of Stefan (for 2 months), 2) under crowding stress (40 individuals in the cage for the first month, 30 for the second month), 3) a combination of those factors, it has been established that hypothyroidism (injection of Mercazolil in the dose 25 mg/kg during the first month, then in a half dose till the end of the experiment) reduces, while small doses of L-thyroxine (1,5 - 3,0 mcg/ kg for 28 days, then - 1,5 mcg/kg until the end of the study), on the contrary, increase the resistance of dental solid tissues to caries. The dental solid tissues resistance increase to caries by iodine-containing thyroid hormones is caused by the increase of the structural and functional stability of the enamel, its density, the mineralizing potential, the level of calcium and the antioxidant activity in the saliva.

In structure of stomatologic diseases the periodontitis takes the third place after caries of teeth and a pulpitis, in an age group of 34-47 years the frequency of this form of complications of caries reaches 50%. Results of treatment of a chronic apical periodontitis at 45 patients are given in article. The total of the cured teeth made 47. In the main group (25 patients) applied complex treatment with use of introduction in a periodontium the center of the destruction of tissues behind an apex of osteoplastic materials namely enriched with blood plasma thrombocytes. It is established that use of the specified combination by 30 days promotes acceleration of processes of a reparation of a bone tissue of a periodontium and leads to reduction of terms of treatment. It is confirmed with indicators of optical density of a bone tissue at a chronic apical periodontitis by means of methods of a radioviziografiya and a computer tomography.

Chronic apical periodontitis ranks third in terms of referral to a dentist. The main role in the development of this disease is attributed to the microbial factor. Therefore, in the treatment of chronic apical periodontitis, a qualitative antibacterial treatment of the root canal is necessary. Ultrasound is one of the methods of disinfection. With the help of clinical research, as well as microbiological examination of the microflora of the root canals of the teeth before and after antibacterial treatment, the anti-inflammatory and antimicrobial effect of ultrasound was assessed.

Dynamics and proportions of proinflammatory and anti-inflammatory cytokines in patients with dental implantation were studied. In 106 patients with dental implants without complications, the study was performed before and after 7-10, 30 days. IL-1β, IL-6, TNF-α, IFN-γ, IL-4, IL-10 were determined in the gingival fluid by solid-phase enzyme immunoassay. A significant increase in the level of TNF-α and IL-10 was observed on day 7-10, and TNF-α at day 30. At 7-10 days after implantation, an imbalance in the ratio of IL-1β / IL-10, TNF-α / IL-4, TNF-α / IL-10 was observed in comparison with the control, the proportion of pro- and anti-inflammatory cytokines was almost normalized on day 30, Only the ratio of TNF-α / IL-10 remained elevated. The enhanced synthesis of pro-inflammatory cytokines was countered by the enhanced synthesis of IL-10, which in our opinion is related to the ability of IL-10 to inhibit the cytotoxic activity that TNF-α exerts.

The results of the studies made it possible to substantiate the efficiency of the use of the ultrasonicated bactericidal solution of nanosilver during disinfection of Root Canal Systems. On the basis of clinical observations, it was revealed that when nanosilver is used as a bactericidal agent with a prolonged biocide effect, the number of patients with negative dynamics of apical chronic periodontitis treatment decreases in the near and distant observation periods.

With the purpose to study the mechanisms of formation and peculiarities of chronic gingivitis course in patients with chronic infectious diseases, the examination has been carried out of 45 patients with gingivitis on the background of HIV-infection, hepatitis C, chronic brucellosis; 15 patients with gingivitis without infectious diseases and 45 patients with infectious diseases without gingivitis. It was determined that in the patients with gingivitis and chronic infectious diseases the development of local inflammatory reaction is characterized by increased frequency of recurrence of gingivitis with its prolongation. The endogenous intoxication which is caused primarily by the chronic infectious diseases, play the main role in the forming of clinical specificity of gingivitis in patients with co-morbidities.

The present study aimed at the development of an endodontic simulation model, able to implement the electronic method of working length determination (EAL) in a setting of undergraduate learning. The development of the simulation model was accompanied by several investigations, helping to assess products’ potential and aiming to create the sound scientific basis for its future implementation as a learning tool. This investigation was conducted in the framework of the regular phantom-lab course. During the initial implementation 450 student have been trained. The models’ capability to imitate clinical conditions was investigated by means of radiographic, macrophotograpic and CAD/CAM techniques. The EAL-features of the present model allowed not only for precise determination of apical constriction (R²=0,0198) versus radiographic method (R² = 0,0019), but also granted a precise preparation of the apical constriction in the vast majority of cases (up to 83%).

A method is presented that allows creating plastic patterns in the laboratory using computer tomography data, laser surface scanning of teeth, as well as a number of computer programs, the use of which in endodontic dentistry can accurately determine the topographic dimensions of their coronary cavities. The use of this method in the clinic will significantly save the loss of hard tissues of teeth when creating endodontic access.

Dens invaginatus (dens in dente) is a frequent malformation of the hard tissues of the tooth the maxilar permanent lateral incisors. This anomaly is often not identified by the dentist during examinations and are not correctly diagnosed in the treatment. On the basis of a clinical case of chronic periodontitis of the tooth 1.2, which was specified malformation in combination with the wrong early diagnosis, developed perspective of the phenomenon in relation to the upper second incisors. Recommended x-ray diagnostics of all lateral upper incisors, visually discovered a blind fissure. Also discusses the use of the material Biodentine as an alternative to endodontic treatment in the case of extensive destruction of dens invaginatus malformation.

The frequency of the decay of the ceramic materials used was Vita-95 and Noritake, and methods for their recovery have been proposed. In 119 patients with sintered prosthesis, 63 bridges were examined, 34 of which were made of Noritake and 29 from Vita-95. Of the 56 metal-ceramic crowns, 30 were manufactured using Noritake and 26 crowns using Vita-95. The disintegration of prostheses made from the mass of Noritake and Vita-95 was noted in 53,8 ± 6,2% and 46,2 ± 6,7% of cases, respectively. In 19,3 ± 8,2% of cases, ceramic decays were observed in molars and premolars in the chewing plane of the mandible. At Vita-95 after firing of an opaque ceramic layer, microcracks were detected in 8,6 ± 1,4% of cases, when using Noritakе material - in 13,3 ± 1,7% of cases, which is 1,5 times more often (p < 0, 05). According to the comparative analysis, the ceramic material Vita-95 (Germany) was more effective than the ceramic mass of Noritakе (Japan). To restore the prosthesis proposed two options: restoration by laboratory methods and directly in the oral cavity.

The evaluation time ranges from 6 months to 2 years and 47 patients were examined. The material comprised 97 teeth restored with 156 quartz fiber posts. We did final postendodontic restoration after sanation or after we noticed positive dynamics. Patients were from 18 to 71 years old. All the teeth were previously endodontically treated with vertical condensation of warm gutta-percha and eugenol-free sealer. 62 treated teeth were restored with one post, 20 teeth had two posts, 15 teeth had three posts, and only 9 teeth with oval-shaped canals were restored with the accessory posts. In observation time we didn’t find out any complications, discoloration of teeth, debonding and fractures of posts.

Relevance of the research topic: modern bleaching systems are based on the use of hydrogen peroxide preparations or carbamide peroxide, in combination with activating factors. Hydrogen peroxide acts as a strong oxidant by the formation of free radicals, reactive oxygen molecules and hydrogen peroxide anions. Many researchers believe that the discoloration of tooth whitening is determined primarily by changes in the dentin. Others dispute the idea of color change in dentin and believe that it occurs only in enamel, masking unchanged dentin. Objective: to study histological changes in the structure of hard tooth tissues during whitening. Materials and methods: 12 intact teeth removed by orthodontic indications after in vitro bleaching procedure and 4 intact teeth not subjected to the bleaching procedure were selected. To whiten teeth, a system was used that included a gel based on 24% hydrogen peroxide (Amazing White Professional). After the bleaching procedure, histological preparations were made and the study was carried out using a microscope mVIZO-101 (OJSC LOMO, Russia). Results: the surface of the enamel after bleaching had a significant number of wedge-shaped defects, as well as a slight delamination. In the upper and middle third of the enamel, cavity changes in the form of pores in a significant amount were observed. The dentinal tubules were enlarged, the location was not traced. Conclusions: a single photochemical bleaching procedure leads to significant morphological changes in the structure of hard tissues of the teeth, which manifest themselves as wedge-shaped defects in the enamel, as well as the appearance of cavities in the enamel-dentine border and the heterogeneity of dentin with a significant number of pores.