АннотацияПредмет. Применение провизорных (временных) конструкций является важным моментом с точки зрения биологии, эстетики, биомеханики. Новые бис-акриловые материалы помогли устранить некоторые проблемы, связанные с традиционными акриловыми материалами. Однако их недостатком является возможность поломки в зонах повышенного напряжения.Цель исследования -изучение прочности на изгиб балок-образцов, выполненных их акрилата и бис-акрилата, после починки.Методология. На универсальной испытательной машине исследовали 7 групп образцов в зависимости от материала (самотвердеющей акриловой пластмассы Re-fine Bright (Yamahachi Dental MFG., CO., Japan) или самотвердеющей бисакриловой композиционной пластмассы Protemp 4 (3М ESPE)), а также способа починки сломанных образцов. Фиксировали силу разрушения, вычисляли средние значения и ошибку средней. Проверяли нормальность распределения результатов. Определяли статистические различия между группами с использованием непараметрического критерия Краскела-Уоллиса.Результаты. Выявлены существенное снижение прочности у всех склеенных образцов для бис-акрилата (группы 2, 4; p<0,05) либо тенденция к этому (группы 3, 5; 0,050,05).Выводы. Сравнение усилий разрушения на изгиб балок из бис-акриловой композиционной пластмассы Protemp 4 выявило существенное ослабление прочности после любых видов починки. При починке балок из акриловой пластмассы Re-fine Bright посредством той же пластмассы с мономером прочность восстанавливается практически до первоначальной.Ключевые слова: акрилаты, бис-акрилаты, склеенные балки-образцы, прочность на изгиб

Background. To date, numerous retrospective studies on the use of resin-bonded fixed partial dentures (RBFPD) have proven their reliability. Nevertheless, there are still questions about the design of posterior resin-bonded fixed partial dentures for replacing 1 and 2 missing teeth. Objectives. The present research was an in vitro study of the fracture strength of resin-bonded fixed partial dentures (RBFPD) with movable connector on the heat-pressed ceramic minor retainer when replacing 1 or 2 missing premolars. Methods. The laboratory research was carried out to study the fracture strength of fixed/movable RBFPD on acrylic moulds with a space equivalent to one or two premolars. The nature of RBFPD destruction and breaking loads in newtons were assessed by comparing the mean values according to the t-test. We studied 4 groups of RBFPD, depending on the type of retainer and the number of lost teeth. Results. The smallest fracture strength (1017.0 ± 49.0 N) was observed in the group with two missing teeth. In groups with 1mm thick occlusal rest, its deformation was observed. In the groups with 2 mm thick occlusal rest, partial fracture of the ceramic minor retainer was observed. Fixation loss of the adhesive wings or cast crowns as a large retainer was not observed. Conclusions. Fixed/movable RBFPD replacing two missing premolars are less fracture resisted then when replacing one missing premolar. Fixation loss of the large retainers was not observed. Adhesive wings were as effective as cast crowns as a large retainer.

Background. Joint pain is often associated not only with disc displacement but also due to the level of inflammatory mediators in the synovial fluid. Injections of platelet growth factor not only expand the joint cavity, performing a purely mechanical function but also create a high concentration of growth factor in the synovial fluid, which favorably affects the cartilage tissue, joint capsule, ligamentous apparatus. Objectives ― to study the effectiveness of platelet growth factor in the complex treatment of patients with TMJ malfunctions. Methods. A clinical examination of two groups of patients (50 people) aged 18 to 67 years with a malfunctions of TMJ was conducted. Were used in all patients in the complex: splint therapy, myogymnastics, and manual traction drive. For the first group (25 people), concentrated growth factor in the liquid phase (PRP) was used in the treatment. For the second group (PRP) was not used. The patients were divided into two groups randomly. Results. The results of the study were carried out according to the following criteria: pain in TMJ with a maximum opening of the mouth, protrusion, laterotruzii, sound phenomena in TMJ, myofascial pain (palpation), the presence of deviation/deflection of the lower jaw, incisional distance. Conclusions. 1. Complex therapy, including splint therapy, myogymnastics, manual traction of the disc, the use of platelet growth factor, showed good results in the treatment of TMJ malfunctions. 2. According to all the studied criteria (pain in TMJ with a maximum opening of the mouth, protrusion, laterotruzii, sound phenomena in TMJ, myofascial pain (palpation), the presence of deviation/deflection of the lower jaw), the most effective result of treatment was obtained after 1 month.