Effectiveness of glaze in reducing color change and staining in denture bases and 3D-printed teeth: An in-depth colorimetric analysis

Objective: To evaluate the effectiveness of a glaze in reducing the discoloration in aged resins used for denture bases and denture teeth (heat-polymerized and 3D-printed) when exposed to a coloring substance. Methods: Specimens (20 × 10 × 10 mm) were obtained using denture base resins: heat-polymerized (HT) and 3D-printed (P and C), and attached denture teeth: prefabricated in acrylic resin (AT) or 3D-printed (T_P and T_C). Samples were divided into two groups: unglazed and glazed (n = 32). They underwent thermal cycling (10,000 cycles) and were immersed in distilled water and coffee for 7 days. CIELab color differences were determined at eight points of each sample using a spectrophotometer, before thermocycling and after immersion in the solutions. The coordinates (ΔL∗, Δa∗, and Δb∗) and ΔE00 data were analyzed using the Mann-Whitney test to compare treatments within each resin type, the Friedman test for over time evaluation, and the Kruskal-Wallis test to compare resins within each treatment type. Results: Glazing of aged resins and staining with coffee reduced color changes, rendering them lighter, redder, and less yellowish (p  0.05). Conclusions: Glaze treatment effectively reduced coffee-induced staining on aged 3D-printed denture base resins and denture teeth. Clinical significance: The application of light-curing glaze to the resin on 3D-printed denture bases minimizes coffee-induced discoloration, preserving aesthetics and prolonging the longevity of the denture.