Methods: Four different shades of acrylic resin denture teeth were selected from three manufacturers. The teeth were evaluated in two phases: Phase I, upon staining for 7 days in distilled water (control Group A), red wine (experimental Group B) and coffee (experimental Group C), and Phase II, upon artificial ageing in a Weather-Ometer for a total exposure of 150 kJ/m2 (control Group A; Phase I). Denture tooth positioning jigs were fabricated and color data recorded by means of an intra-oral spectrophotometer and expressed using the Commission Internationale d’Eclairage (CIE) L*a*b* color notation system. Means and standard deviations were determined. The staining data were analysed by three-way ANOVA, while the artificial ageing data were analysed by two-way ANOVA. Fisher’s PLSD intervals were calculated at a significance level of P >0.05.
Results: In the staining experiment, the main effects of stains and denture teeth and the two-way and three-way interactions among stains, denture teeth and shades were significant of P> 0.05). The same was true for the main effects of denture teeth and shades and their interactions in the ageing experiment.