Biomorphic porous Ti6Al4V gyroid scaffolds for bone implant applications fabricated by selective laser melting

Gyroid structures exhibiting interconnected porosity and mean curvature of zero have the closest resemblance to native bone. Interconnected Ti6Al4V pores of different sizes such as 250, 300, 350 and 400 µm were designed and fabricated using selective laser melting (SLM). The fabricated samples were analysed for microstructure using Scaning electron microscopy and phases using X-ray Diffraction. The prevailing trend of decrease in compressive strength with increase in pore size was observed during compression tests; among all the pore sizes, 250 µm pore size showed an excellent compressive strength of 205 MPa. The biocompatibility of such porous structures for bone tissue engineering was evaluated using Human mesenchymal stem cells (hMSCs) through Alamar Blue^® assay and visualization of cytoplasm and nucleus using fluorescence microscopy. Gyroid scaffold with pore size 350 and 400 µm displayed the highest biocompatibility; however, 250 µm pore size demonstrated an optimum combination of overall mechanical and biological properties viable for practical applications.