Porous Ti-10Mo alloy fabricated by powder metallurgy for promoting bone regeneration

Abstract

Porous Ti-10Mo alloys were fabricated by powder metallurgy using a space-holder method. The pore characteristics, microstructure, mechanical properties, in vitro biocompatibility, and in vivo osseointegration of the fabricated alloys were systematically investigated. The results show that with different weight ratios of the space-holder (NH 4-HCO 3) added, all of the porous Ti-10Mo alloys sintered at 1,300°C exhibited a typical Widmanstätten microstructure. The porosity and average pore size of the porous structures can be controlled in the range of 50.8%-66.9% and 70.1-381.4 μm, respectively. The Ti-10Mo alloy with 63.4% porosity exhibited the most suitable mechanical properties for implant applications with an elastic modulus of 2.9 GPa and a compressive yield strength of 127.5 MPa. In vitro, the alloyconditioned medium showed no deleterious effect on the cell proliferation. The cell viability in this medium was higher than that of the reference group, suggesting non-toxicity and good biological characteristics of the alloy specimens. In vivo, after eight weeks' implantation, new bone tissue formed surrounding the alloy implants, and no noticeable inflammation was observed at the implantation site. The bone bonding strength of the porous Ti-10Mo alloy increased over time from 46.6 N at two weeks to 176.4 N at eight weeks. Suitable mechanical properties together with excellent biocompatibility in vitro and osteointegration in vivo make the porous Ti-10Mo fabricated by powder metallurgy an attractive orthopedic implant alloy.

Design and performance evaluation of additively manufactured composite lattice structures of commercially pure Ti (CP–Ti)

“…It is well known that the pore features, such as porosity and pore size, can significantly influence the biological properties of implants [ 44 ]. In this study, the pore features are directly related to the strut radius.…”

“…For example, with a larger strut radius, the pore size and the porosity decrease which leads to an increase in the volume and the surface area. However, there is a reduction in specific surface area ( Table 2 ), which is not beneficial for adhesion, proliferation, and differentiation, and the transportation of nutrients [ 44 , 45 ]. Meanwhile, with the larger strut radius, the maximum von-Mises stress becomes smaller, which is beneficial for the mechanical properties.…”

Magnesium in Synthesis of Porous and Biofunctionalized Metallic Materials

“…Considering that allowing successful osseointegration is one of the main requirements of dental and orthopedic implant materials, the porous structures are highly promising for those applications. It has also been reported that macro-pores are beneficial for multiple biological processes as cell attachment, ingrowth of osteoblasts, vascularization, and osteoconductivity [85]. However, an adequate vascularization requires pores with diameters larger than 100 μm, specifically in the range from 100 to 500 μm [15,86].…”

The effect of Cu content on corrosion, wear and tribocorrosion resistance of Ti-Mo-Cu alloy for load-bearing bone implants

“…It should be noted that the surface of all the samples formed stable oxide films before sliding. When sliding started the formed mixed oxide films were damaged by the mechanical attack at the contact region [40,41], leading to a sharp decrease in the OCP. However, when the de-passivation and passivation rates reached a dynamic equilibrium, the OCP values became relatively stable.…”