Dual properties of zirconia coated porous titanium for a stiffness enhanced bio-scaffold

Porous titanium (Ti)-based scaffolds are a promising approach for achieving stiffness reduction. To be used as a biomaterial, porous Ti scaffolds (P-Ti) must have suitable wear and corrosion resistance and the generation of either metallic wear debris or Ti ion release should be insignificant throughout a large timescale. The present study combines a porous structure appropriate for cell ingrowth with a physically and chemically stable thin-film coating to create a load-bearing bio-inspired scaffold. The as-designed zirconia-coated P-Ti (Z-P-Ti) was made via a hydrothermal process, followed by a sol-gel method. Mechanical tests were conducted primarily on P-Ti, and chemical stability tests were conducted on Z-P-Ti. The biocompatibility test results correlated with cell mitigation into Z-P-Ti were compared with those for reference surfaces. The results show that Z-P-Ti is load-bearable with an increased surface hardness and roughness. 3T3 cell morphology and viability assessed using the live/dead cell staining protocol show a significant enhancement of cell affinity on the surface of Z-P-Ti. The combination of porous Ti, a load-bearable structure, and biocompatible zirconia coating makes the designed biomaterial promising for many applications, such as vertebral discs. (C) 2017 Elsevier Ltd. All rights reserved.