Search

The Aim of the Study: Comparative study of the precision of the junction of modern implant systems with standard and custom abutments., Materials and Methods: The study was carried out by the method of computed X-ray microtomography on an X-ray microtomograph Heliscan micro CT using the ImageJ program in the laboratory «Systems for Microscopy and Analysis» of the Skolkovo Technopark. The measurement of the gap width between the implant and the abutment for each sample was carried out at 20 points according to the algorithm: the total length of the connection between the implant and the abutment; step (distance) between 5 equidistant points along the contact between the abutment and the implant; the measurements were repeated in 2 perpendicular sections along the joint node axis. The study was conducted on the example of seven implant systems common in Russia. The effect on the implant-abutment assembly of a multiple functional load of 250 N at an angle of 45° (7.6 million cycles) was studied., Results: It has been established that the precision of the junction of modern implants with standard abutments is different and is characterized by the length of the contact from 268 to 1300 µm, the gap at the level of the platform from 5.0 to 11.7 µm, and the asymmetry of the contact in diameter by 2.4-14.2 µm. Abutments individually made in modern CAD/CAM laboratories do not have significant dimensional differences with standard abutments, but they have technological defects. The functional load expands and deforms the gap between the implant and abutment junction in the upper half of their contact., Conclusion: The results obtained demonstrate the capabilities of the computer X-ray microtomography method, which can be used to control the quality of manufacturing collapsible dental implants, the accuracy of manufacturing individual abutments in CAD/CAM laboratories, as well as in the development of new dental implant systems. The dimensional parameters of the junction node determine the advantages of the deep cone connection of the implant and the abutment.

Aim: To compare dental and psychological status in athletes of Olympic teams and the population of Moscow., Materials and Methods: In order to study the features of the dental rehabilitation of Olympic athletes, a comparative study of the dental and psychological status of 132 athletes was carried out when they were included in the Olympic teams and 104 residents of Moscow of the same age. Clinical x-ray examination was supplemented by «Hamburg testing» of the masticatory apparatus and psychological examination using common questionnaires and scales., Results: The study revealed a difference in the status of dental status, the results of the "Hamburg Testing" and psychological examination between athletes of the Olympic reserve and the population of Moscow of the same age. Athletes showed a lower quality of previous treatment of caries and its complications, insufficient oral hygiene, more frequent detection of chronic periodontitis, diseases of the oral mucosa, secondary deformations of the dentition, pathological phenomena of the temporomandibular joint, masticatory apparatus dysfunction according to the results of the "Hamburg Testing". Athletes also established psychological status features: higher rates of reactive and personal anxiety, the presence of depressive manifestations, lower quality of sleep and quality of life., Conclusion: The revealed patterns can provoke muscle hyper-tone and muscular-articular dysfunction of the maxillofacial region, which must be taken into account during the dental rehabilitation of athletes of Olympic teams.

The Aim: To identify the problematic issues of assessing the hygienic state of the oral cavity and the clinical development of possible algorithms for their solution using our modified, highly sensitive (up to 150 CFU/ml versus 5·10 6 -5·10 8 CFU/ml), objective (2-3% error) method fluorescence spectroscopy., Material and Methods: In a clinical study on 20 patients of working age, it was shown that the authors modified fluorescence spectroscopy method allows each patient to individually perform a comprehensive digital express indication and objective analysis of the oral hygiene state based on express registration and analysis of the entire aggregate of aerobic-anaerobic microflora of various oral biotopes (biotope teeth, lips, gums, cheeks, palate, tongue and saliva) online., Results: Integral indicators of the hygienic state of the oral cavity in individuals with satisfactory oral hygiene before and after brushing have been obtained, which describe the hygienic state of both the oral cavity as a whole and individual biotope in their relationship., Conclusion: The results made it possible to substantiate a more objective quantitative methodology for assessing the hygienic state of the oral cavity for the implementation of its individually substantiated clinical use with the identification of the biotope (biotopes) of the mouth, which is the main source of its pollution.

Superelastic titanium alloys (titanium-niobium-zirconium and titanium-niobium-tantalum) are considered to be the more advantageous choice for dental implants than titanium alloys due to their physico-mechanical properties close to those of the bone tissue. Morphological studies of the biocompatibility of these alloys in comparison with titanium were carried out in vivo. Scanning electron microscopy and microprobe elemental analysis of the tissue along the interface between the bone and titanium/superelastic titanium alloys showed similar morphology and elemental composition both on days 30 (poorly mineralized connective tissue was detected in sites of contact with titanium alloy samples) and 90 after surgery (the surface of the titanium alloy samples was covered with mineralized tissue similar by its composition to the surrounding bone).

We studied the stress-strain state of the bone tissue and maxillary full-arch fixed implantretained denture. Load was applied to the anterior (150 N) and posterior (250 N) parts of the denture supported by 6 or 4 implants, including zygomatic ones and placed by on-all-4 treatment technology. The obtained stress values in the bone tissue, implants, and denture show a large strength margin of structural materials. At the same time, the bone strength values were low, especially around the zygomatic and distal implants of all-on-4-implants-supported dentures when the posterior part of the denture was under load.

Aim: To analyze the effectiveness of orthodontic treatment in 7-9 years old children, dental status in children residents of Moscow was compared with 15-17 years adolescents with completed bite formation., Material and Methods: The adolescents were divided into two groups: those who received orthodontic treatment during the mixed dentition period and those who did not receive the treatment. A WHO survey chart was used to assess the dental status of children (WHO, 2013) with additional section 'Dentoalveolar anomalies'. DMFT and DMFT+dft, OHI-S, CPI, PAR, Little irregularity index and DAI were assessed in all groups. The need for dental and orthodontic treatment was calculated., Results: Dental morbidity in Moscow children during the mixed dentition period was characterized by a high prevalence of caries (92.0%) with an intensity of 1.67±0.03, the 17.0% prevalence of premature teeth loss and dentoalveolar anomalies in 73.9% of children with a combination of anomalies in 60.8% of children. Orthodontic treatment in the mixed dentition period is associated with systematic professional control and by the age of 15 years results in two-fold reduction in the intensity of caries and periodontal disease, proper detection of poor hygiene and the lower prevalence of abnormal positioning of the teeth (crowding and misalignment of teeth) and the improvement of dental arches ratio (completely eliminating cross-bite). At the same time early orthodontic treatment has no significant effect on the prevalence of tooth rotation, interdental spaces, deep, open, distal, mesial occlusion and displacement of dental arches., Conclusion: Orthodontic treatment of children during the mixed dentition period is indicated in cases of crowding and displacement of teeth, as well as cross-bite; with respect to other types of dentoalveolar anomalies, early orthodontic treatment is only justified by the severe impact of dentoalveolar anomalies on psychological and functional indicators.

In order to analyze the complexity and cost of methods of modern orthodontic treatment for children in the mixed bite period as well as to determine the necessary costs for eliminating dentoalveolar anomalies in primary school children taking into account the prevalence of anomalies we studied the duration and frequency of orthodontist visits during treatment using the 2x4 technique, a removable plate with artificial teeth, a ring with a spacer, a plate with a front bite pad, a plate with a shutter for the tongue, and Twin-block appliance, Dilar mask in combination with an expansion apparatus, plates with a screw, appliance with a hyrax expansion screw. Based on the complexity the salary of the orthodontist and other personnel, the costs of maintaining the doctor’s workplace and the dental technician are calculated. The cost of consumables at the clinical and dental stages was determined considering the purchase prices and the cost of a specific manipulation by weighing or measuring. When calculating the necessary funding for early orthodontic treatment modern data on the prevalence and structure of orthodontic pathology in children during the mixed bite period were used. It was found that the complexity of modern orthodontic treatment during the mixed bite period varies from 5.55 hours (spacer with a ring for premature loss of a temporary tooth) to 10.73 hours in the treatment of a distal bite with a twin-block device. The cost of orthodontic treatment in mixed bite varies from 12.6 thousand rubles (a spacer with a ring for premature loss of a temporary tooth) to 33.4 thousand rubles for the treatment of a mesial bite using a Dilar mask in combination with an expanding device. Given the prevalence of dentoalveolar anomalies in children during mixed bite period, the necessary financial costs for orthodontic treatment per child examined should be at least 30 thousand rubles, and at least 40 thousand rubles for a child with a dentoalveolar anomaly.

The purpose of the study was to study the stress-strain state of bone tissue and a permanent prosthesis on implants installed in the frontal part of the upper jaw. The 150N load was applied to the frontal and 250N to the side of the non-removable prosthesis on six or four implants, including zygomatic and 'All-On-Four' technology. The values of stresses in bone tissue, implants and prosthesis are obtained, which show a large margin of strength in structural materials. At the same time, the bone strength is low, especially around the zygomatic implants and the extreme implants 'All-on-4' with the load of the lateral part of the prosthesis.

For evaluation of the efficiency of bone substitute, nanostructurized Gamalant-paste-FORTEPlus was placed into a mandibular defect in rats. Bone tissue reparation was evaluated after 30 days by histological methods under a microscope. Use of bone substitute in experimental mandibular defect ensured more complete and rapid restructuring of the bone tissue in comparison with the control (natural healing).

The aim of the study were protocols of dental care in departmental sanatoriums for workers with hazardous working conditions (HWC). Provided dental care and staff features were analyzed in 10 sanatoriums basing on their annual 2016 reports. In Central Clinical Sanatorium 'Malakhovka' dental care need was assessed in 402 males (mean age 39.2±1.2 years) with HWC. The study results were used for guidelines of departmental 'Dental care in resort rehabilitation of workers with hazardous working conditions'.

The article analyzes the results of dental examination of employees with hazardous and normal working conditions in Atomenergomash enterprise with various dental care organization regimens and provides clear evidence of the effectiveness of serial attendances care in enterprise dental offices in terms of reduction in the dental treatment needs. Additional funding for departmental dental services was calculated by comparing the real cost of dental treatment and MHI tariffs allowing implementation of proposed dental care program.

The article presents the results of the survey of 150 dentists from 10 closed administrative units of FMBA health care system of Russia in connection with the dynamics of dental staff withdrawal and reduce of volume of preventive work in schools and factories. These problems were found to be associated with the lack of regulations on mandatory preventive dental examinations of workers with occupational hazards, low tariffs for dental services in obligatory medical insurance program, poor wages an lack of apartments for young dentists.

The long-term results of implant retained restorations with casted and milled frames were compared in clinical and experimental settings. Electrochemical features of milled and casted titanium by contact with titanium implant were assessed. The biocompatibility of milled and casted titanium was studied in mesenchymal stem cells culture. Cross sections were used to assess the marginal fit precision of milled and casted frames.

Bone tissues of human skull, jaws and dental hard tissues are formed under mastication loads acting as functional irritants and thus maintaining their physical qualities. Knowledge of tensions and deformations in bony structures allows creating favorable conditions for dental implant placement and function.

Experience in substantiation, development and implementation of the system of quality of treatment-prevention help control in clinical stomatological centre of the Russian FMBA was described. Indices of stomatological status and quality of stomatological treatment in 35-44 age group in case of traditional organization of quality control in departmental stomatological clinic was given, comparison of the stomatological diseases intensities with the corresponding indices in Moscow and Russia was conducted. Improving dynamic depending upon the volume of stomatological treatment was traced and preferences of fool oral cavity sanation with inclusion of dental prosthetics making were revealed. The system of quality of treatment control based upon organization of consultative expert room was suggested, its efficacy was shown at the analysis of qualitative and quantitative indices of the mentioned above clinical centre work during 2 years in dynamic.

Results of experimental-clinical substantiation of computer technology of intraosseous dental implantation (Materialise, SiCat) planning and new computer technology of optical implantation navigation Monadent were expounded. Results of precision measurement of implant installation into experimental model according to computer planning data were brought. By the example of clinical analyses data of implantation efficacy in 352 patients the advantages of preliminary computer implantation planning were shown. When interviewing doctors and patients benefits of computer implantation planning were disclosed in cases when the plan of treatment was coordinated with the patient. It was forecasted that the use of computer planning in practical implantology would be widened.

Math modeling of mandible was executed in the presence of intraosseous implant in lateral part of dentition. Deflected mode of cortical bone tissue around implant, in alveolus and other mandible parts were studied in case of vertical load of 250 N upon implant. Values of tension in cortical bone tissue in the region of incisors, canines, molars and jaw body spreading in mediodistal, buccolingual and vertical directions were received. Integral tensions were analyzed.

Math modelling "removable dentures-implantate-bone" with size and density of bone tissue as variables was created. It allowed to study biomechanical bases of mandibular bone tissue structures interaction with full removable dentures of different constructions and fixed on intraosseous implantates. Analysis of the received data showed that in the majority of cases it was expedient to recommend 3 bearing (abutments) system of denture making. Rest on 4 and more implantates was appropriate for patients with reduced density of spongy bone and significant mandibular bone atrophy. 2 abutment system can be used in patients with high density of spongy bone and absence of mandibular bone atrophy.