Effect of Whitening Toothpaste on Surface Roughness and Colour Alteration of Artificially Extrinsic Stained Human Enamel: In Vitro Study

Objective: The aim of this study was to compare five toothpastes in terms of alteration of surface roughness and colour of red-wine-stained human enamel over time after brushing simulation. Methods: Stained specimens were randomly divided into five groups (n = 8): Oral-B Gum and Enamel (C), ZACT Stain Fighter (ZW), Colgate Optic White Volcanic Mineral (CW), Oral-B 3D White Luxe Fresh Breath (3DW), and Thepthai (TW). The colour and surface roughness of the specimens were measured after brushing simulation for four durations; two weeks, one month, six months, and twelve months. Abrasive particles in toothpaste were inspected under a scanning electron microscope. Results: Surface roughness was increased in the specimens that underwent brushing simulation in all groups (p < 0.05). ZW (6.33 +/- 0.98 mu m) exerted the most changes in surface roughness for all durations. Other groups showed similar surface roughness at each time point. Delta E-00 and Delta L were increased in all groups until twelve months; however, there were no significant differences between C (Delta E-00 = 30.17 +/- 4.16, Delta L = 38.19 +/- 4.34), CW (Delta E-00 = 24.25 +/- 10.52, Delta L = 31.12 +/- 11.00), and TW (Delta E-00 = 29.00 +/- 3.96, Delta L = 36.68 +/- 4.53) at any time period. Moreover, ZW (Delta E-00 = 45.6 +/- 8.01, Delta L = 53.03 +/- 6.71) and 3DW (Delta E-00 = 43.6 +/- 7.33, Delta L = 51.03 +/- 6.47) exhibited a substantial change and were statistically differed from the other groups after four-weeks. Various characteristics of abrasive particles were inspected under SEM. Conclusion: All five toothpastes increased the surface roughness altered the colour of red wine-stained human enamel over time.