Staining resistance of denture bases produced with different techniques

Purpose: To evaluate the color stability of heat-pressed, CAD/CAM, and 3D printed complete denture resins. Materials and Methods: A total of 90 disk shape resin specimens were manufactured from conventional heat-polymerizing, CAD/CAM subtractively manufactured, and additively manufactured denture resins (n=30); were divided into three groups according to staining solution as coffee, red wine, and distilled water (as a control). Baseline color measurements were performed with a spectrophotometer. The specimens were immersed in solutions for a total of 7 days at 37 °C and second measurements were performed. Color changes were calculated with the CIEDE 2000 (ΔE00) formula. Color differences were assessed using two-way ANOVA (p = 0.05), and the paired t-test was used to compare the L, a, and b parameters in each group before and after staining. Results: Significant color differences were found among the resins and staining solutions. All of the color differences were found in the clinically acceptable range (ΔE00<1.8) except in the heat-pressed group in red wine. Red wine was found to be the most colorant agent among the solutions tested. The heat-pressed resin group demonstrated significantly higher ΔE00 in comparison to the other groups in all aging media (p <.001). Conclusion: The staining resistance of denture resins was influenced by the production technique. Subtractively manufactured, and additively manufactured denture resins were not inferior to conventional resins in terms of color stability.