Dental implants of TiTa 30 produced by powder technology

摘要

The production and the mechanical properties of porous parts of the biocompatible titanium alloy TiTa30 produced via powder metallurgy are described. The aim of the study was to create endosseous dental implants with a low Young's modulus and a porous surface, which will result in a good load transfer from the implant to the bone thus stimulating the formation of new bone and ultimately by the ingrowth of bone into the surface of the implant lead to a good anchorage in the bone. Other applications of such porous parts might be bearings or filters. The new alloy TiTa30 was melted in an electric-arc furnace in a water-cooled mould in an argon atmosphere and then powdered by the hydrogenation - dehydrogenation (HDH)- process. Samples were produced by unidirectional pressing and then sintering of the green bodies under vacuum. The influence of the sintering parameters (particle size, compacting pressure, sintering time and temperature) on the mechanical properties was investigated. While the Young's modulus and the yield strength varied only with the resulting porosity, the fatigue strength of the samples also depended on the particle size and the sintering temeprature and time. It was possible to produce samples with a Young's modulus comparable to that of bone nd a fatigue strength high enough for use as a dental implant. In addition to the mechanical testing the functionality of the implants (bone ingrowth and implant anchorage) was dtested in-vivo in animal experiments.