[The use of intraosseous appliances considering the anatomical features of the hard palate]. / Ispol'zovanie vnutrikostnykh apparatov s uchetom anatomicheskikh osobennostei tverdogo neba.

OBJECTIVE: The aim of the study. To improve the effectiveness of patients' treatment with narrow upper jaw by improving the stability of intraosseous devices. MATERIALS AND METHODS: 40 patients with the narrow upper jaw, from 12 to 40 years old, were treated. 50 self-drilling orthodontic miniscrews of each manufacturer, i.e. «BioRay¼, Taiwan, «Turbo¼, Russia, a total of 100 items, were inserted into a palate. RESULTS: The greatest thickness of the cortical bone relative to the sagittal plane was observed at a distance of 6 mm from the incisor canal, which averages 6.32 mm. Relative to the transversal plane, the greatest bone thickness was observed 3 mm laterally from the median palatine suture and averages 7.62 mm. The smallest thickness of the mucous membrane of the hard palate is noted 6 mm distal from the incisor canal and 3 mm laterally from the palatine suture is on average 4.56 mm. CONCLUSION: The protocol for determining the individual position of the miniscrew for each patient, taking into account all his anatomical features, is a necessary tool for clinical success.

[Manufacturing of zirconia restorations by means of additive fabrication. Part 2]. / Ispol'zovanie additivnykh tekhnologii dlya izgotovleniya zubnykh protezov iz dioksida tsirkoniya. Chast' 2.

Additive fabrication (AF) or layer-by-layer synthesis technologies is one of the most dynamically developing areas of digital production. Modern additive technologies can be used to fabricate zirconia-based restorations. The second part of this article will present the fabrication of zirconia restorations using additive technologies such as selective laser sintering (SLS), selective laser melting (SLM), binder jetting (BJ), robocasting (fusion deposition modeling, FDM), as well as the advantages and disadvantages of the mentioned technologies. The analysis of the presented works indicates the need for further research aimed at optimizing 3D printing of zirconia restorations.

[Manufacturing of zirconia restorations by means of additive fabrication. Part I]. / Ispol'zovanie additivnykh tekhnologii dlya izgotovleniya zubnykh protezov iz dioksida tsirkoniya. Chast' I.

Additive fabrication or layer-by-layer synthesis technologies is one of the most dynamically developing areas of digital production. Modern additive technologies can be used to fabricate zirconia-based restorations. The first part of this article will present the fabrication of zirconia restorations using additive technologies such as stereolithography, digital light processing, selective laser sintering, selective laser melting and inkjet printing, as well as the advantages and disadvantages of the mentioned technologies.

[Comparative evaluation of traditional and speed sintering of dental ceramics based on zirconium dioxide]. / Sravnitel'naya otsenka traditsionnogo i skorostnogo obzhiga stomatologicheskoi keramiki na osnove dioksida tsirkoniya.

This study analyzed the traditional and high-speed firing of dental ceramics based on zirconia. The types of furnaces for sintering zirconia, the basic principles of traditional, high-speed and super-speed firing, as well as the effect of the sintering protocol on the structure, physical, mechanical, optical properties, wear and marginal fit of zirconia were evaluated. The analysis showed that it`s necessary to develop a special optimal sintering technique using particular protocols in specific types of furnaces for each dental ceramic material based on zirconia, taking into account the composition and structure of the ceramics. To write this review, articles from the electronic databases of Medline, PubMed and the websites of dental journals were used.

[Reinforcement of photosensitive material for bases of orthodontic appliances]. / Armirovanie svetootverzhdaemogo polimera dlya bazisov ortodonticheskikh apparatov.

OBJECTIVE: The objective of the study was to improve the strength properties polymer by modifying its basis with various materials. MATERIAL AND METHODS: A polymer in the form of a pink-colored plasticine mass with veins was studied, a quartz mesh «Quartz splint mesh¼ manufactured by RTD (France) and two metal gold-plated wire mesh (0.1 mm and 0.15 mm in diameter) manufactured by Renfert (Germany). Modified test specimens, 65×40×3.5 mm in size were covered with a lavsan film and at a slight pressure the material was rolled out with a glass cylinder flush with the frame. Curing was carried out in Fhotopress photopolymer (Aveyron, RF) under the 460-470 nm wavelength light for 6 minutes on each side. The plates were sawn with a mill in the form of strips 64×10×3.3 mm and kept in distilled water at 37 °C for 50 h before testing. The test of the reinforced samples was carried out with a middle and lower location of quartz and metal grids pre-treated with adhesive and subjected to a 4-point bending test. Bending strength, bending modulus, and fracture deformation were determined using a Zwick/Roell Z010 testing machine with a constant crosshead speed under loading (5±1) mm/min. The statistical significance of the influence of reinforcing elements on the performance of the basic physical and mechanical properties of the base material was determined using Student's t-test. RESULTS: The value of fracture toughness index K1 at the lower location of the quartz mesh was 3.72±0.43 MN/m1.5, which was 4.9 times significantly higher than K1 for the non-reinforced material (p=0.0001). CONCLUSION: The ability to achieve maximum material strength with the lower reinforcement method increases the functional usefulness of removable orthodontic and orthopedic structures with a basis of «Nolatek¼ light-cured material.

[Adhesion of dental cements to zirconia restorations. Part 2]. / Adgeziya tsementov k keramicheskim zubnym protezam iz dioksida tsirkoniya. Chast' 2.

The information about methods of surface preparation for dentures made from ceramic based on zirconium dioxide for better adhesive fixation is presented in the first part of this article. Micromechanical methods of preparation for cementation of the surface of a zirconia dental prosthesis are discussed in the first part of this article. The second part of the article provides an overview of scientific research on chemical methods for preparing a surface made of zirconia and the problem of the bond strength of polymer cement with a prepared surface made of zirconia.

[The experimental study of a Russian orthodontic mini-screw]. / Eksperimental'noe issledovanie otechestvennogo ortodonticheskogo minivinta.

BACKGROUND: The aim of this research is the experimental study measuring stability of the orthodontic miniscrews «Turbo¼ designed in Russia in comparison with its foreign analogues, namely, «Vector Tas¼ (USA) and «BioRay¼ (Taiwan). MATERIAL AND METHODS: Four self-drilling orthodontic miniscrews of each manufacturer, i.e. «Vector Tas¼, USA, (10-mm length, 2-mm diameter), «BioRay¼, Taiwan, (10-mm length, 2-mm diameter), «Turbo¼, Russia, (9-mm length, 2-mm diameter), a total of 12 items, were inserted into native pig mandible sample. Their stability was estimated by torques using a dynamometer (Zahoransky AG, Germany) and «Periotest¼ device («Periotest M¼, Germany). This experiment was conducted in native pig mandible sample immediately after the screws' placement and in 7 days after loading at an angle 70°. RESULTS: After application of a load, the decreased torque values and increased Periotest values were registered in all orthodontic miniscrews. CONCLUSION: Orthodontic miniscrews «Turbo¼ designed in Russia are slightly inferior to «VectorTas¼ miniscrews and superior to «BioRay¼ miniscrews in primary stability and stability after 7 days under loading.

[Fluorescence of zirconia-based dental ceramic materials]. / Fluorestsentsiya stomatologicheskikh keramicheskikh materialov na osnove dioksida tsirkoniya.

The review contains information about the fluorescent properties of natural teeth, fluorescent additives, fluorescent liquids for staining zirconium dioxide, fluorescent powders, pastes, glazes, and cements for zirconia, methods for measuring fluorescence. Factors affecting the fluorescent properties of ceramics are also reported.

[Adhesion of dental cements to zirconia restorations (part 1)]. / Adgeziya tsementov k keramicheskim zubnym protezam iz dioksida tsirkoniya (chast' 1).

The analysis of modern scientific data on traditional and adhesive fixation of zirconia restorations, adhesion of various cements to zirconium dioxide, methods of surface preparation of ceramic restorations is presented. Micromechanical methods of preparation for cementation of the surface of a zirconia dental prosthesis are discussed in Part 1.

[Translucent zirconia ceramics for fabrication monolithic restorations: review. Part 2]. / Prozrachnaya keramika na osnove dioksida tsirkoniya dlya izgotovleniya monolitnykh zubnykh protezov: obzor publikatsii v mezhdunarodnykh zhurnalakh. Chast' 2.

Translucent zirconia ceramics for fabrication monolithic restorations is a ceramic material of latest generation. The objective of this literature review is discussing the ways to increase the transparency of zirconia, novel technologies of its manufacturing (part 1) and laboratory procedures for fabrication translucent zirconia restorations, factors affecting the transparency, optical and physico-mechanical properties of the material, as well as indications for its use (part 2).

[Translucent zirconia ceramics for fabrication of monolithic restorations: review. Part 1]. / Prozrachnaya keramika na osnove dioksida tsirkoniya dlya izgotovleniya monolitnykh zubnykh protezov. Obzor publikatsii v mezhdunarodnykh zhurnalakh. Chast' 1.

Translucent zirconia ceramics for fabrication monolithic restorations is a ceramic material of latest generation. The objective of this literature review is discussing the ways to increase the transparency of zirconia, novel technologies of its manufacturing (part 1) and laboratory procedures for fabrication translucent zirconia restorations, factors affecting the transparency, optical and physico-mechanical properties of the material, as well as indications for its use (part 2).

[Comparative clinical evaluation of the prosthetic treatment quality of molars restored by chairside manufactured CAD/CAM crowns]. / Sravnitel'naia klinicheskaia otsenka kachestva ortopedicheskogo lecheniia moliarov CAD/CAM koronkami metodikoi chairside.

AIM: A comparative clinical evaluation of the results of prosthetic treatment with chairside CAD/CAM crowns for molars made from hybrid ceramics VITA Enamic, blocks of feldspatic ceramics VITABlocs Mark II, blocks of leucite glass IPS Empress CAD. MATERIAL AND METHODS: The study involved 30 patients aged from 19 to 60 years old with defects in hard tissues of molars. For clinical evaluation we used 'Clinical criteria for evaluation of direct and indirect restorations' developed by FDI in 2007, which included the assessment of several aesthetic, functional and biological parameters. We also included 2 additional criteria indicators: the condition of the antagonist tooth and the hygienic condition of the prosthesis in comparison with the hygiene of natural teeth. All patients were randomized into 3 groups of 10 people. After the treatment the clinical quality assessment was carried out in the following time intervals: 30 minutes, 1, 6, 12, 18, 24 months after the fixation of the crown. RESULTS: Clinical evaluation of the results of prosthetic treatment of 30 patients with chairside CAD/CAM crowns made from three different materials did not reveal any significant difference in the clinical criteria for evaluation of direct and indirect restorations within 24 months.

[Modern home-manufactured materials for non-metal dental restorations]. / Sovremennye otechestvennye materialy dlya bezmetallovykh zubnykh protezov.

Metal-free dentures are currently made of 3 types of materials: polymers, composites and ceramics. The present report is devoted to the current status of the production and use of domestic structural materials for metal-free dentures.

Technological features of metal-ceramic prosthesis frameworks manufactured from domestic alloys of precious and base metals. / Tekhnologicheskie osobennosti izgotovleniya litykh karkasov metallokeramicheskikh zubnykh protezov iz otechestvennykh splavov blagorodnykh i neblagorodnykh metallov.

The aim of the study was to examine changes in physical and mechanical properties of dental alloys depending of the initial composition at re-casting. Russianc precious alloys: Plagodent (AuPtPd) and Palladent (PdAu) and base alloys: Vitiriy-N (NiCrMo) and Vitiriy-C (CoCrMo) were used as study samples, which were divided in three groups: a primary casting from the granules; 50% of re-casting; 100% of re-casting. We investigated the yield strength in bending, coefficient of thermal expansion and hardness. Changing in the composition of the alloys has led to changes of all physical and mechanical properties.

[STUDY OF COLONIZATION PROCESSES AND PERSISTENCE OF MICROORGANISMS IN ARTIFICIAL MATERIALS FOR MEDICAL USE].

AIM: Study processes of microbial colonization and persistence of microorganisms in polymer materials for medical use. MATERIALS AND METHODS: Samples (1 x 1 cm plates) of polymer plastics for production of removable dental prosthesis based on polyurethane and acryl were used, that were incubated with clinical isolates of Pseudomonas aeuruginosa, Staphylococcus aureus in Luria-Bertani broth nutrient media for 24, 48 hours and 7, 14 days and for 1, 5 and 3 months at a temperature of 37 degrees C. Dynamics of interaction process of microorganisms with polymer materials were studied using scanning electron microscope Quanta 200 3D (FEI Company, USA). The samples were fixated after incubation with 10% of neutral formaldehyde, dehydration with alcohols or acetone, typical for SEM, was not carried out, that allowed to conserve the native structure of the samples, including exo-cell matrix of biofilms. RESULTS: Electron-microscopical data on stages of interaction of bacteria with the surface of medical plastics were obtained. Biofilms were shown to be formed on abiotic surfaces and biodestructive changes of plastics appeared. A question on the possibility of prolonged persistence of pathogenic for human microorganisms in artificial prosthesis is discussed. CONCLUSION: The developed experimental model of formation of biofilm on abiotic surfaces could be the basis for carrying out studies directed on the fight with biofilms, by using SEM.