Titanium-Zirconium Binary Alloy as Dental Implant Material: Analysis of the Influence of Compositional Change on Mechanical Properties and In Vitro Biologic Response.

Abstract

To evaluate the mechanical properties and biologic response of single-phase Ti-Zr alloys cast in higher-purity casting conditions, with comprehensive compositions (from 10 to 90 mol% of Zr). The mechanical properties and in vitro biologic response with proportional increase of Zr to Ti-Zr alloy composition were assessed. Tensile strength, surface hardness, and Young's modulus were examined. The in vitro cell response of the alloys was also tested with mouse osteoblast cells. Analyses of mechanical tests demonstrated improved strength and reduced Young's modulus on this binary alloy system. In vitro cell culture studies with osteogenic MCT3T-E1 cells exhibited the highest attachment rate with the largest and more mature cells on Ti10Zr, instead of commercially pure Ti, whereas a significantly lower cell attachment rate and delayed alkaline phosphatase-specific activity (ALP) differentiation were detected on Ti50Zr. The results revealed that the composition did have an impact on the in vitro biologic response. Ti-Zr alloys with 50-50 mol% composition had a decreased biologic response, although the mechanical properties improved. The overall highest strength was Ti with 30 mol% Zr without significant decrease of biologic response.