Příprava a hodnocení mechanických vlastností biokeramiky

Abstract

Thesis is focused on the preparation and characterization of porous bioceramic material for biomedical applications based on silicon nitride. Silicon nitride is a very promising biomaterial due to the combination of its mechanical properties, wear resistance, chemical inertness, low density and good biocompatibility. Theoretical analysis and description of biomaterials and their properties is in the first part of the thesis, where the used materials and their use in the form of bone tissue replacement are also described. Another important issue is the structure of the trabecular bone tissue, which will be replaced by the material. The first aim of the work was to prepare spherical ceramic particles with defined porosity and increased bioactivity and their characterization. The second goal was to use porous particles for the preparation of composite materials using calcium phosphate cement. The experimental part is focused to the preparation of porous ceramic particles prepared from a ceramic suspension containing silicon nitride, which is a bioinert component with good mechanical properties, and calcium phosphate as a bioactive component. The particles were prepared by spraying a stable ceramic suspension into liquid nitrogen and then lyophilizing and sintering. In the next part of the work, the prepared particles are evaluated in terms of structure, size, porosity, mechanical and biological properties. With the characterization of the material, the effects of individual production parameters on the chemical and phase composition of the final products were also described. In the last part, possible methods of particle utilization in composite biomaterials are proposed and experimentally verified. The whole work is an initial design for the production of a new material based on silicon nitride with a wide range of biomedical uses.