In vitro evaluation of tooth-color change using four paint-on tooth whiteners

The effectiveness of four paint-on tooth whiteners was evaluated and compared in this in vitro study. Sixty extracted anterior teeth were selected and randomly assigned to five groups: 1-(AS) Artificial Saliva (Roxane); 2-(MSW) Sparkling White (Meijer); 3-(CNE) Crest Night Effects (Procter & Gamble); 4-(ABB) Beautifully Bright (Avon) and 5-(CSWN) Simply White Night Gel (Colgate-Palmolive). The teeth were cleaned with a soft bristle toothbrush and toothpaste (Procter & Gamble) to remove any residue from the storage solution. The bleaching gels were painted onto the surface of the teeth, and they were then wrapped in gauze moistened with artificial saliva and kept in 100% humidity at 98 degrees F in a laboratory oven (Precision Scientific model 18EG) for 24 hours. The treatment was repeated once a day for 14 days. Visual color assessment was done using a value-oriented Vitapan Classical Shade Guide (Vident) and a colorimeter (Minolta Chroma Meter CR 321). PVS jigs (Exaflex, GC America) were fabricated for each tooth. Visual and colorimetric readings were recorded at baseline, 7 and 14 days. One-way ANOVA and Tukey multiple comparisons test were used to assess differences between groups. CNE and CSWN presented the highest mean number of shade changes and deltaE*ab Colorimeter readings. ABB and MSW did not significantly lighten the teeth, as measured by either method of evaluation after two weeks of the bleaching regimen.