Abstract
Corrosion of implant alloys releasing metal ions has the potential to cause adverse tissue reactions and implant failure. We hypothesized that macrophage cells and their released reactive chemical species (RCS) affect the alloy's corrosion properties. A custom cell culture corrosion box was used to evaluate how cell culture medium, macrophage cells and RCS altered the Tiβ6Alβ4V corrosion behaviors in 72 h and how corrosion products affected the cells. There was no difference in the charge transfer in the presence (75.2 Β± 17.7 mC) and absence (62.3 Β± 18.8 mC) of cells. The alloy had the lowest charge transfer (28.2 Β± 4.1 mC) and metal ion release (Ti < 10 ppb, V < 2 ppb) with activated cells (releasing RCS) compared with the other two conditions. This was attributed to an enhancement of the surface oxides by RCS. Metal ion release was very low (Ti < 20 ppb, V < 10 ppb) with nonactivated cells and did not change cell morphology, viability, and NO and ATP release compared with controls. However, ILβ1Ξ² released from the activated cells and the proliferation of nonactivated cells were greater on the alloy than the controls. In summary, macrophage cells and RCS reduced the corrosion of Tiβ6Alβ4V alloys as hypothesized. These data are important in understanding host tissueβmaterial interactions. Β© 2004 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 717β724, 2004