Reproducibility of Replicated Trabecular Bone Structures from Ti6Al4V Extralow Interstitials Powder by Selective Laser Melting

Abstract

The field of orthopedic regenerative medical studies has begun to use porous metal structures for biomedical implants, which have lower strength and ingrowth behavior, similar to bones. It is possible to produce such porous metal structures with a designable microarchitecture or replicated topology by additive manufacturing. The main purpose of using these artificial pore geometries in the biomedical field is to increase the biocompatibility of the product by imitating the bone. In this study, bone samples from the femoral and vertebral regions of a sheep were obtained and scanned by microfocus computed tomography (Micro-CT). Trabecular bone models were produced from Ti6Al4V extralow interstitials powder using the selective laser melting with 1:1, 1:1.25, and 1:1.50 scales. The produced samples were scanned using Micro-CT, and 3D models were formed. The 3D models of the trabecular bone and samples were aligned in a computer environment to determine deviations in both size and angle of arms in the trabecular structure. It was found that the deviations decreased when the angle was above 60 degrees, whereas they significantly increased with the size below 150 microns. The size distribution and interconnectivity ratio of the pores formed in the production was obtained from the PNMs. It was determined that the mean equivalent diameters of vertebra and femoral pores, from the pore network models are 767 +/- 265 mu m and 623 +/- 245 mu m, and concluded that the samples produced in the scale of 1: 1 and 1: 1.25 could represent the pore size distribution in the bone.