The antibacterial activity of a Ag+-implanted titanium surface modified with a covalent graft of poly(vinylpyrrolidone) (PVP) (Ag+/PVP-Ti) against Escherichia coli (E. coli) colonies was first evaluated in vitro. The result showed that the sterilizing efficiency of Ag+/PVP-Ti was approximately 100% against E. coli while keeping a low Ag+ release amount which was far below the human cell toxicity concentration.