[Character of zinc-modified titanium surface and its antibacterial property to S.mutans]

To evaluate the chemical composition of the zinc modified surface of implanted titanium and to assess its effect on the antibacterial activity in vitro.

Pure commercial titanium discs were modified with zinc by plasma immersion ion implantation and deposition (PIIID) technique. The surfaces were characterized by X-ray photoelectron spectrometer. To measure the bacterial responses, S. mutans were seeded onto the surfaces of discs in 24-well culture plates at a density of 1×10(9) CFU/mL and observed by a scanning electron microscope. The statistical significance of difference was assessed by ANOVA using SPSS 13.0 software package, followed by a Bonferroni test.

The full range XPS indicated that the main difference of zinc PIIID on the disc was the appearance of the signals of zinc and oxygen. At the same time, the relative atomic concentration of zinc increased gradually with the implanting time, the concentration of zinc in Zn-Ti-80 min group being the highest among the groups. The zinc implanted titanium could affect adherence and the form of S.mutans. The adherence amount of bacteria in Zn-Ti-60 min and -80 min group was significantly less than those in cp-Ti group, Zn-Ti-20 min and -40 min group.

PIIID can successfully introduce zinc into pure titanium surface, which can change adherence and the form of S.mutans slightly.