불소이온을 함유한 인공타액 내에서의 Ti-Ag 합금의 부식저항성

Abstract

Fluoride has been one of the most widely studied caries-preventive agent since it was found to be responsible for reduction of dental caries. Dental gels and rinses for caries prophylactic contain fluoride at concentrations ranging from 0.1% to 1%. In addition, many types of fluoride releasing materials have been used in dental applications. The purpose of the study was to investigate the addition effect of fluoride into artificial saliva on the corrosion resistance of pure titanium and titanium-silver alloys. Titanium and titanium-silver alloys were arc-melted, homogenized at 950?C for 72 hours, hot-rolled, and solution heat-treated and quenched. In order to investigate the effect of the fluoride ions on the corrosion resistance, potentiodynamic polarization testing, potentiostatic testing and open circuit potential measurement were performed in artificial saliva containing 0.1% and 1% NaF. Passive current densities of titanium and titanium-silver alloys increased with increasing NaF concentration. Titanium-silver alloys had a higher corrosion resistance than titanium in high NaF concentrations. The open circuit potential of titanium reacted sensitively and decreased with increasing fluoride concentration but that of titanium-silver alloys with a high silver content reacted less sensitively to fluoride ion concentration. Titanium-silver alloys had a higher resistance against the aggressive attack of fluoride ions and showed a more stable open circuit potential and current density than titanium in the fluoride-containing solution. Therefore, it is thought that their use in complicated environments like dental fields could reduce the concern about corrosion by existence of fluoride in oral cavity.