Effect of Various Staining Beverages on the Color Stability of CAD/CAM PMMA Denture Teeth: An in Vitro Study

Objective: This study aimed to compare the color change of computer-aided design (CAD)/computer-aided manufacturing (CAM) polymethyl methacrylate (PMMA) denture teeth and conventional acrylic teeth after immersion in three staining beverages (coffee, red tea, and cola) for a day, 7 days, and 30 days.

Materials And Methods: Group 1: Conventional acrylic teeth (n = 32). Group 2: Milled CAD/CAM teeth out of PMMA disc (n = 32). The specimens of each material were further divided into four subgroups: (1) Control group, distilled water (n = 16). (2) Red tea solution (n = 16). (3) Coffee solution (n = 16). (4) Cola (n = 16). The color change ( ) was assessed using a spectrophotometer at four time points: at the baseline (t ), on the 1st day (t ), on the 7th day (t ), and the 30th day (t ) of immersion. Kolmogorov-Smirnov test was applied, followed by performing independent samples t test, one-way analysis of variance and post-hoc Tukey tests to compare the color change values at different time points.

Results: The mean score of NBS values of the coffee solution indicates perceivable color change at the end of the 30th day in the conventional acrylic teeth group. It was 0.843 ± 0.395 at t , then increased to 1.017 ± 0.477 at t and to 2.259 ± 1.059 at t . There is a statistically significant difference (p < 0.05) in color change values between both tooth types at the end of the 30th day of immersion in red tea solution and a statistically significant difference at the end of the 7th day (p < 0.05) and the 30th day (p < 0.05) of immersion in coffee solution.

Conclusions: CAD/CAM PMMA teeth are more color stable than conventional acrylic teeth after 30 days of immersion in coffee and red tea solution.