Formation of New Bone with Preferentially Oriented Biological Apatite Crystals Using Novel Cylindrical Implant Containing Anisotropic Open Pores Fabricated by Electron Beam Melting (EBM) Method

Abstract

New cylindrical bone implants containing elongated pores interconnected as open pores were fabricated by an electron beam melting (EBM) method from Ti–6 mass% Al–4 mass% V ELI powders of 65 μm in mean diameter. New bone formed in the elongated pores of implant and preferential arrangement of biological apatite c-axis were confirmed along the long bone axis by the microbeam X-ray diffraction method. Bone mass and preferential degree of biological apatite c-axis as a bone quality parameter decreased with the distance from the edge of implant along the longitudinal bone axis because of a stress shielding effect. However, clear interconnection of new bone appeared through the implant with elongated pores parallel to the bone axis, while the defected portion was not recovered with new bone without the new implant.