No abstract

Relevance. The creation of porous three-dimensional materials for bone defects compensation and its subsequent regeneration is an important direction of medical materials science. The key issue in the interaction of an implant and bone tissue is the surface properties of the implant.The purpose of the study is to evaluate the physicochemical properties and compatibility of tissues of a living organism and porous implants with calcium phosphate Zn- and Ag-containing formed by microarc oxidation.Materials and Methods. Implants with various types of porous structure were made by direct laser sintering of titanium alloy Ti-6Al-4V powders. The calcium phosphate coatings, including Zn- and Ag-containing, were formed on the implants surface by microarc oxidation.Results. Coatings, deposited in electrolytes of various compositions, were uniformly distributed over the implants mesh structure. The phase composition of Zn-containing coatings, deposited in the acidic electrolyte, was represented by amorphous calcium phosphates. Ag-containing coatings, deposited in the alkaline electrolyte, had an amorphous-crystalline structure, the crystalline phase of which was identified as tricalcium phosphate in the α and β modifications. The samples of extracts of calcium phosphate Zn and Ag-containing coatings were co-cultured with pFb line of the human postnatal fibroblasts for 48 hours at 37°C in 5% CO2 atmosphere. The MTT test revealed a high metabolic activity of the co-cultured fibroblasts in comparison with the fibroblasts of control.Conclusion. The pFb line of the human postnatal fibroblasts retained their viability for 48 hours of co-culturing with calcium-phosphate Zn- and Ag-containing coatings. The tested product and its components did not negatively affect the cellular respiration. However, further studies are needed to determine the rate of bioresorption and the degree of antibacterial activity of calcium-phosphate Zn- and Ag-containing coatings.

Цель: исследование зависимости физико-механических характеристик опорных каркасов кольца для аннулопластики митрального клапана от режимов его термообработки. Материалы и методы. Оценивали характер изменения кривых «сила-деформация» в условиях одноосного сжатия экспериментальных образцов, обработанных при варьировании температуры, времени и давления во время задания рабочей формы. Результаты. Отмечено, что повышение экспозиции, температуры, а также снижение давления приводило к увеличению жесткости конструкции и прочности в диапазоне малых деформаций. При этом степень влияния температуры и времени сопоставимы по вкладу. В первом случае изменение параметра на 40% (500-700 градусов) вызывало изменение механических свойств кольца в виде прироста силы на 20%. Аналогичное изменение времени (4,5-6,5 мин) термообработки вызывало 27-процентный прирост силы, необходимой для сжатия на 15%. Заключение. Выявленные в работе экспериментальные зависимости позволяют определить основные рекомендованные параметры режима термообработки: диапазон температур 600-700 градусов, экспозиция от 10,5 минуты, давление воздуха в камере печи 0,1-0,5 атм.