Abstract
AIM: This study evaluated the color aging of two computer aided design/computer aided manufacturing (CAD/CAM) provisional materials of different compositions (polymethyl methacrylate and composite resin) after exposure to thermal aging and immersion in coffee for 3, 6, and 12 intraoral months. SETTING AND DESIGN: The current in vitro study was conducted from September to December 2021 at the Craniofacial laboratory at the Saint Joseph University in Beirut, Lebanon. MATERIALS AND METHODS: The shades of 2.0 mm thick, 10.0 mm in diameter disk shaped specimens of VITA CAD Temp(®) and Ceramill(®) TEMP were measured using the VITA Linearguide 3D MASTER(®) and a conversion table to extract the CIE LFNx01aFNx01bFNx01 values on a white background (n = 30). STATISTICAL ANALYSIS USED: The color differences ΔE at 3, 6, and 12 months were calculated and analyzed by repeated measures ANOVA followed by Bonferroni multiple comparisons, univariate analyses, and one sample t tests. RESULTS: The mean ΔE(T1/T0), ΔE(T2/T0), and ΔE(T3/T0) values were significantly higher than the cutoff values for acceptability and perceptibility for the VITA CAD Temp(®) and the Ceramill(®) TEMP groups. In addition, the increase in ΔE overtime was significantly greater in the Ceramill(®) TEMP group compared to the VITA CAD Temp(®) group. CONCLUSIONS: The Ceramill(®) TEMP changed color more and faster than the VITA CAD Temp(®). In addition, whether at 3, 6, or 12 months, the color variations of both materials are not only perceptible but also unacceptable compared to the initial shade.