Yumi Imamura, DDS, Masayuki Otsuki, DDS, PhD, Alireza Sadr, DDS, PhD, and Junji Tagami DDS, PhD
Cariology and Operative Dentistry, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University. Tokyo, Japan
Purpose: This study evaluated the effect of sodium fluoride (NaF) solution and casein phosphopeptide- amorphous calcium phosphate (CPP-ACP) paste on the prevention of re-staining after in-office bleaching in vitro using an artificial discoloration tooth model.
Materials and Methods: Fifty extracted bovine teeth were stained in black tea and bleached by an in-office beaching material (TiON In Office). The teeth were divided into five groups, with 10 teeth in each group (n=10). They were treated with 2.0% or 0.2% NaF solution, CPP-ACP paste (MI Paste) or CPP-ACP paste containing fluoride (MI Paste Plus) for 1 hour. A group left without application served as control group. Then, each tooth was immersed into the black tea again. CIE L*a*b* of the stained surface of each tooth was measured by a dental color meter (Shade Eye NCC) after bleaching, at 1, 3, and 6 hours, and 1, 2, 3, and 7 days after immersion, and the changes in color were evaluated. Other specimens were prepared and the bleached and stained surfaces were observed by a scanning electron microscope (SEM) at each period.
Results: Color change increased gradually by immersion in the black tea in all groups. The color change in all experimental groups was less than that of control group. Repeated measure ANOVA showed that both the treatment solution and the immersion time significantly affected ΔE (p<0.05). A remarkable difference was not found in the SEM images among all groups at each period.
Conclusion: It was concluded that application of NaF and CPP-ACP would be able to decrease re-staining and discoloration of teeth after office-bleaching.
(Asian Pac J Dent 2013; 13: 47-55.)
Key Words: CPP-ACP, re-staining, sodium fluoride, tooth bleaching