Effect of nonthermal atmospheric discharge on tooth bleaching

Ayaka Kusanagi, DDS, Masayuki Otsuki, DDS, PhD, and Junji Tagami, DDS, PhD

Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan



Purpose: The purpose of this study was to evaluate effect of nonthermal atmospheric discharge on tooth bleaching in vitro by color measurement using a dental colorimeter and an industrial colorimeter.
Materials and Methods: The air stream of nonthermal atmospheric discharge was exposed on the hematoporphyrin stained paper for 5, 10, 20, 30, and 60 minutes respectively. The air stream without atmospheric discharge (negative control) and a commercially available tooth bleaching material (positive control) were also prepared. The L*a*b* values on the treated surface at each step was measured by a dental colorimeter and an industrial colorimeter. Color difference was calculated from those values. The artificial discolored bovine teeth samples were prepared and exposed by the air stream of atmospheric discharge for 5, 10, 20, 30, and 60 minutes, and the color change was evaluated.
Results: The nonthermal atmospheric discharge showed bleaching effect for both hematoporphyrin stained paper and artificial discolored bovine teeth. Although the measured color values of both colorimeters were not consistent statistically, they showed high correlation.
Conclusion: It was concluded that nonthermal atmospheric discharge showed the bleaching effect and two colorimeters were useful for measuring color of hematoporphyrin stained paper and artificial discolored bovine teeth.
(Asian Pac J Dent 2018; 18: 7-14.)
Key Words: atmospheric discharge, color meter, plasma, tooth bleaching