In vitro comparison of the color degradation of two computer-aided design/computer-aided manufacturing provisional materials: A 12-month simulation.

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.