The effect of staining solutions on the color stability of provisional prosthodontic materials

Objectives: The aim of this study was to evaluate the effects of staining solutions on the color stability of self-cure provisional resin materials. Methods: The specimens were prepared for each of three auto-polymerized bis-acryl resin and auto-polymerized methyl methacrylate provisional resin material. The baseline color values were measured with a colorimeter according to the CIE L(*)a(*)b(*) color scale. After the first measurement (T-0), specimens were placed in staining solutions (coffee, coca-cola, burn and distilled water for control group) and the other measurements were taken after 24 h (T-1), 1 week (T-2) and 4 weeks (T-3). Results: Data were analyze statistically by (a) repeated measures (ANOVA), (b) one and two way ANOVA, and (c) Tukey HSD multiple comparison tests. At the 24 h immersion period, the post hoc analysis indicated that AccessCrown-coffee revealed the highest Delta E-* values (4.4). At the second immersion period (1 week), Structur2 SC-coffee had the highest Delta E-* values compared with other materials (5.4). Conclusions: The degrees of discoloration were increased with immersion time. The methylmethacrylate resin was more resistant to discoloration than bis-acryl resins. After immersion for 30 days, the coffee solution resulted in unacceptable discoloration for all the tested materials. (C) 2012 Elsevier Ltd. All rights reserved.