Effect of Metal Released from Ti Alloy Wear Powder on Cell Viability

Ti alloy disks were separately worn with pins of the same alloy or apatite ceramics in Eagle's medium. Wear powders sterilized in either a heating oven or ethanol were separately added to culture media. The effect of the Ti wear powder sterilized in a heating oven on cell viability was smaller than that of powder sterilized in ethanol. The effect of wear powder generated with the apatite ceramic pin on cell viability was also larger than that generated by the alloy pin. The relative growth ratios of L929 and MC3T3-El cells for Ti-6Al-4V alloy wear powder sterilized in ethanol decreased from a smaller amount than those of the Ti-15Zr-4Nb-4Ta and Ti-15Sn-4Nb-2Ta alloy wear powders. The concentration of V released from the wear powder into the medium increased moderately with increasing wear powder. This effect was approximately in agreement with the results estimated from medium extraction with high-purity V particles. For the Ti-15Zr-4Nb-4Ta and Ti-15Sn-4Nb-2Ta alloy wear powders sterilized in ethanol, the maximum Ti concentration released from the wear powder was approximately in agreement with the results obtained with high-purity Ti particles. On the contrary, for Zr, Nb, Ta and Sn, the maximum metal concentrations released from the wear powders were lower than those obtained with high-purity metal particles.