ИСТИНА

Implants based on biocompatible materials can be used for restoring the functions of damaged bone tissue and replacing the lost bones. When a polymer with viscoelastic mechanical properties is introduced into the materials, it is possible to create a composite material that could be reversibly deformed over wide range without significant stressing surroundings. In addition to the similarity of their chemical composition to that one of native bone, architecture of the material should facilitate the flow of biological fluxes, bone ingrowth (i.e., osteoconductive properties) and determine the required mechanical characteristics (strength/ stiffness). This work was aimed at the development of osteoconductive composite materials with viscoelastic properties based on calcium phosphate-filled hydrogels for their use in the reconstruction of bone tissue. The following tasks were accomplished: a) fabrication of layered calcium phosphates (brushite CaHPO4∙2H2O and octacalcium phosphate (OCP) Ca8(HPO4)2(PO4)4∙5H2O); b) design of osteoconductive architecture of implants in sense of reaching high permeability and low stiffness; c) testing the ways of uniform filling of hydrogels by calcium phosphates; d) search for optimal parameters of stereolithography 3D-printing of composite hydrogel/calcium phosphate implats, viz., type and concentration of photoinitiator, the degree of dilution of the monomer, the degree of loading the gel with calcium-phosphate powder; e) carrying out the rheological, mechanical and biology tests of the biocomposites.