Bioactive bone substitutes for load-bearing applications

The development of biomimetic materials able to regenerate long bone segments is a need of ever increasing relevance, due to the strong impact of bone diseases on human health, quality of life and healthcare costs. Bone regeneration requires biomaterials and devices able to mimic chemistry, morphology and mechanical properties of the living tissues. In this respect, the present work illustrates, under different perspectives, the development of biomimetic materials for bone repair, so as to outline a roadmap for the development of regenerative bone scaffold. Firstly, the chemical aspects of bone mimesis are discussed by describing the development of multi-substituted hydroxyapatite (HA). Then, in the perspective of increasing the mechanical strength of bio-devices, for application in the regeneration of segmental bone defects, the synthesis of new ceramic composite materials, based on HA and calcium silicates, is discussed. Finally a conceptually new approach to mimic the unique morphological features of bones is discussed: taking inspiration by Nature, biomimetic bone scaffolds with hierarchically organized structure can be obtained by biomorphic transformation of natural woods.