In vitro biocompatibility studies of fibroblast cells on Ti-Ta alloys

Medical science has enabled the substitution and reinforcement of body organs and tissue through the evolution of better materials. Metallic implants have been utilized to aid in injury wound healing as bone replacements, endoprosthesis, and percutaneous devices. Of concern with metallic devices is the prolonged effects and service life of the implant. It is known that metallic dissolution and premature failure can occur in the body leading to complications for the host. In an effort to provide more corrosion resistant materials with adequate strength for better resistance against high cycle fatigue, Ti-Ta alloys are presented to compete with current, popular materials such as Ti6A14V. This research focuses on the binary alloy systems of Ti40Ta and Ti50Ta alloys for implant consideration. Three heat-treated versions of the Ti-Ta system that demonstrated high strength properties were also assessed. Cell culture testing of NIH-3T3 fibroblast cells was conducted to perform biocompatibility testing on these metal substrates. MTT cytotoxicity assays were performed to evaluate cellular behavior on the metal substrates. Flow cytometry assays were conducted to analyze rates of cell growth and cycling to determine best surface conditions among these metals. Results indicate very similar cellular activity on the Ti alloys and to a lesser degree on the commercially pure titanium and tantalum. Flow cytometry tests showed similar cellular growth rates on the different materials and on the control plastic. MTT assays indicate a higher degree of proliferation on the Ti-Ta alloys and on the Ti6A14V. Although the Ti and Ta elemental materials supported slightly fewer cells on their surface, differences were minimal. Ti-Ta alloys appear to be comparable if not slightly more compatible than the standard Ti6A14V.