Analysis of preferential apatite/collagen orientation in bones and development of bone implants for inducing sound orientation

Abstract

Bone is a natural composite material with anisotropic hierarchical structure predominantly consisting of collagen fibrils and biological apatite (BAp) crystals, where the crystallographic c-axes of the BAp well aligns with the long axis of the collagen fibrils. This anisotropic micro-organization is believed to be responsible for anisotropic mechanical functions which bones exhibit [1]. Indeed, the BAp orientation was proven to be a pivotal determinant of Young's modulus of bone [2] using regenerating long bones. Therefore, reconstructing and/or maintaining the appropriate BAp/collagen orientation is quite important in bone therapies including orthopedic implantation. In this presentation, we introduce the BAp/collagen orientation analyzed in the normal and regenerated bones, and propose novel implant devices that was developed aiming at maintaining a soundness of bone's anisotropic microstructure.

[1] T. Nakano et al.: Bone 31, 479-487, 2002.

[2] T. Ishimoto, T. Nakano et al.: J. Bone Miner. Res. 28, 1170-1179, 2013.