[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.

[Laboratory assessment of deformational features in thermoplastic materials for removable dentures].

The paper presents the results of laboratory tests of base thermoplastic materials Acry F711 and Flexi N512 in comparison with the traditional acrylic base material Ftoracs to study their deformational properties when loaded by repetitive forces close to the functional chewing loads.

[Polyurethane denture base material "Pentalur" and modified polyurethane compositions: comparative study of mechanical properties].

Results of laboratory tests of polyurethane based material "Pentalur" conducted to determine its mechanical properties proved the material to meet basic requirements for removable dentures materials. The introduction of simple poluethers with certain molecular weight as well as 1,4-butanediol allows varying polyurethane properties in a fairly wide range. This range of polyurethane mechanical properties along with good biocompatibility opens new possibilities in creation of removable dentures with improved functional properties as well as maxillofacial prosthesis.

[Special basic material for microwave polymerization of AKR-MV]. / Spetsializirovannyi bazisnyi material dlia mikrovolnovoi polimerizatsii AKR-MV.

Some physical and mechanical properties of the new acrylic material ACR-MW for microwave polymerization, the base material Etacryl-02 ("Stoma", Ukraine) and their analogue Acron MC (GC Lab Technologies Inc., Japan). The findings suggest that the new special denture base material ACR-MW for rapid microwave polymerization (3 min at 100%) possesses the highest bending strength with lower water absorption and solubility. The properties of ACR-MW meet the requirements of ISO 1567.

[Characteristics of wearing resistance of materials for repair of masticatory teeth]. / Iznosostoikost' materialov, ispol'zuiushchikhsia dlia vosstanovleniia zhevatel'nykh zubov.

Wear resistance parameters were evaluated for 5 materials used for masticatory teeth filling. The study was carried out on an Uism-1 device for evaluation of abrasion resistance of dental materials by the friction method during circular movement of a premolar (removed for orthodontic indications) along the surface of reference material. Similar abrasion resistance in the material-tooth pair was detected for 4 materials: Herculite XRV (Kerr-Sybron), Unirest (Stomadent), Dyract AP (Dentsply/De Trey), and Tytin amalgams (S.S. White); the parameters of wear differed. The highest wear of material paralleled by high tooth abrasion were detected for Filtek P-60 (3M/Dental) material.

[A light-hardened polymeric material for metal-plastic whole-cast fixed dentures]. / Polimernyi material svetovogo otverzhdeniia dlia metalloplastmassovykh tsel'nolitykh nes''emnykh zubnykh protezov.

Self-hardening material for metal plastic permanent dentures, has been developed by the Central Research Institute of Dentistry for the first time in Russia. Its physicomechanical properties are described and the results of toxicological trials are presented. The new material is superior in wear resistance to foreign analogs Kulzer Dentacolor and ESPE Visio-Gem. Toxicological studies demonstrated the biological inertness of the material during long contact with the internal media of human organism and the absence of toxic, sensitizing, and mutagenic action.