2007 Volume 50 Issue 3 Pages 373-378
The purpose of this study was to investigate the effect of bleaching agent with titanium dioxide and lowconcentration hydrogen peroxide in terms of tooth color and roughness of the enamel surface. Pyrenees® (Mitsubishi Gas Chemical Company) and Shofu Hi-Lite™ (Shofu) were used as bleaching agents. A powerful standard halogen lamp, Hyperlightel (Kuraray Medical), was used as a light source for the experiment. The bleaching agents were applied on bovine enamel. The tooth color was measured with a spectral color-difference meter for micro-surface, VSS300H (Nippon Denshoku), and evaluated with the CIE L*a*b* color system. A handysurf E-30A (Tokyo Seimitsu) was used for measuring the roughness of the enamel surface (Ra) after each treatment. Twenty bovine crowns were assigned to two groups: group P was bleached with Pyrenees, and group H was bleached with Hi-Lite. The ΔE*ab was 3.38 on average with group P and was 3.65 on average with group H. The post-treatment L* levels in groups P and H were significantly higher than the pre-treatment levels. a* levels in the two groups gradually increased, but there was no significant difference compared with the pre-treatment levels. The post-treatment b* levels in the two groups were significantly lower than the pre-treatment levels. There was no significant difference among the two groups. The post-treatment Ra in the two groups showed no significant difference compared with the pre-treatment levels. From the results of this study, it was suggested that Pyrenees could develop the same effects as Hi-Lite.
