Nanostructured Hybrid Materials for Bone Tissue Regeneration

The study of materials for bone tissue repair is one of the most important subjects in the field of materials research for biomedical applications. Bone can be considered as a biological hybrid material composed of an organic component, collagen, and an inorganic one, nanocrystalline carbonate hydroxyapatite (CHA). Both phases integrate each other into a nano-metrical scale in such a way that the crystallite size, nanofibers orientation, short range order between both components, etc. determine its nanostructure and therefore the function and mechanical properties of each kind of bone. On the basis of bone regeneration, new biomaterials have been developed. These materials stimulate the bone tissue formation by promoting the osteoblast proliferation and differentiation. One of the most promising alternatives is to apply materials with similar nanostructure to that of natural bone tissue. In this sense, the nanotechnology and the development of organic-inorganic hybrid materials provide excellent possibilities for improving the conventional bone implants. The present article reviews the advances in silicate - containing hybrids for bone tissue repair, as well as the chemical methodologies that allow to control the material nanostructure. Special attention is paid to bioactive hybrid materials, which are able to produce biological apatites on their surfaces when they are in contact with physiological fluids.