ЛАБОРАТОРНОЕ ИЗУЧЕНИЕ ПРОЧНОСТИ НА ИЗГИБ АРМИРОВАННОГО БИС-АКРИЛОВОГО МАТЕРИАЛА ДЛЯ ПРОВИЗОРНЫХ ПРОТЕЗОВ

Abstract

Background. The use of provisional (interim, temporary) restorations has become a routine procedure in modern dentists after the end of the era of brazed-stamped bridges. The use of traditional acrylic plastics does not provide the necessary strength for the long-term functioning of provisional prostheses. Bis-acrylic materials have helped to eliminate some of the problems associated with traditional acrylic materials. However the disadvantage of bis-acryls is that they can break relatively easily when placed in areas of increased stress. The use of provisional prostheses, obtained by casting or CAD/CAM technology, undoubtedly solve problems, however, prosthetics are significantly more expensive. Another known and cheaper way is to harden polymers by reinforcing them. Objectives ― to study, when conducting a mechanical test, the fracture resistance of glass fiber-reinforced bis-acrylic composite beams. Methods. On a universal testing machine (three-point flexural test), 8 groups of samples were studied depending on the material — Re-fine Bright acrylic material (Yamahachi Dental MFG., CO., Japan), or Luxatemp bis-acrylic material (DMG) and Protemp 4 (3M ESPE), and also, the method of reinforcement of Protemp 4 with GlasSpan fiberglass tape (GlasSpan). The fracture strength (F) was calculated in MPa. Statistical differences between groups were determined using T-test. Results. Comparison of the fracture strengths results between the first control group (Protemp 4 bis-acrylic plastic without reinforcement) and other groups (glass tape reinforcement) revealed a significant hardening of Protemp 4 after reinforcement (p <0,05). Conclusions. The use of reinforcing glass tape with a full impregnation with an adhesive and a flowable composite increases the strength of Protemp 4 more than 2 times.