Экспериментальная модель для исследования биологически детерминированных взаимодействий в области контакта имплантат - костная ткань

Aim: a) to develop the method for surface modification of polytetrafluoroethylene (PTFE) by applying a nanostructured metallic or ceramic coating, b) to study the possibility of using this obtained structures with different coatings as an experimental model for analysis of the fine interactions in the contact implant-tissue zone. The study demonstrates that the surface modification of PTFE by magnetron sputtering of nano-Ti and Ti-Ca-P-C-O-N leads to increased integration potential of materials. Data obtained indicate that the designed constructions can be successfully used as an experimental model for studying the interactions of implant - tissue interface elements of periimplant area.В задачи работы входило: а) разработка метода модификации поверхности политетрафторэтилена (ПТФЭ) путем нанесения наноструктурного металлического или керамического покрытия; б) исследование возможности использования полученной таким образом конструкции с различными по составу покрытиями в качестве экспериментальной модели для исследования тонких взаимодействий в области контакта имплантат - тканевые элементы периимплантационной зоны. Исследование продемонстрировало, что модификация поверхности ПТФЭ путем магнетронного напыления нанопокрытий Ti и Ti-Ca-P-C-O-N приводит к повышению интеграционного потенциала материалов. Полученные результаты свидетельствуют о том, что разработанные конструкции могут быть с успехом использованы в качестве экспериментальной модели для изучения взаимодействий в области интерфейса имплантат - тканевые элементы периимплантационной зоны

Characteristics and in vitro response of thin hydroxyapatite-titania films produced by plasma electrolytic oxidation of Ti alloys in electrolytes with particle additions

The enhancement of the biological properties of Ti by surface doping with hydroxyapatite (HA) is of great significance, especially for orthodontic applications. This study addressed the effects of HA particle size in the electrolyte suspension on the characteristics and biological properties of thin titania-based coatings produced on Ti–6Al–4V alloy by plasma electrolytic oxidation (PEO). Detailed morphological investigation of the coatings formed by a single-stage PEO process with two-step control of the electrical parameters was performed using the Minkowski functionals approach. The surface chemistry was studied by glow discharge optical emission spectroscopy and Fourier transform infrared spectroscopy, whereas mechanical properties were evaluated using scratch tests. The biological assessment included in vitro evaluation of the coating bioactivity in simulated body fluid (SBF) as well as studies of spreading, proliferation and osteoblastic differentiation of MC3T3-E1 cells. The results demonstrated that both HA micro- and nanoparticles were successfully incorporated in the coatings but had different effects on their surface morphology and elemental distributions. The micro-particles formed an irregular surface morphology featuring interpenetrated networks of fine pores and coating material, whereas the nanoparticles penetrated deeper into the coating matrix which retained major morphological features of the porous TiO2 coating. All coatings suffered cohesive failure in scratch tests, but no adhesive failure was observed; moreover doping with HA increased the coating scratch resistance. In vitro tests in SBF revealed enhanced bioactivity of both HA-doped PEO coatings; furthermore, the cell proliferation/morphometric tests showed their good biocompatibility. Fluorescence microscopy revealed a well-organised actin cytoskeleton and focal adhesions in MC3T3-E1 cells cultivated on these substrates. The cell alkaline phosphatase activity in the presence of ascorbic acid and β-glycerophosphate was significantly increased, especially in HA nanoparticle-doped coatings