Impact of resin composite cement on color of computer-aided design/computer-aided manufacturing ceramics

Abstract

Objective: To analyze the impact of the color of a resin composite cement (RCC) on the optical properties of different computer-aided design and computer-aided manufacturing (CAD/CAM) ceramics.

Materials and methods: Specimens (N = 220, thickness: 0.9 ± 0.03 mm) were fabricated from: leucite (Initial LRF Block/IPS Empress CAD), lithium disilicate (Amber Mill/IPS e.max CAD), lithium metasilicate (Celtra Duo), and lithium alumina silicate ceramic (n!ce) in translucency levels HT and LT. All specimens were bonded with an RCC (Light+/Warm+). Color was analyzed (spectrophotometer) initially as well as after bonding of RCC with CAD/CAM ceramics using CIELab and CIEDE2000. Kolmogorov-Smirnov test, one-way ANOVA and t test served for analyzing (α = 0.05).

Results: Highest impact on ΔE presented the choice of ceramic (η_p² = 0.155/p < 0.001), followed by translucency level (HT/LT; η_p² = 0.050/p = 0.001) as well as interaction between ceramic and translucency level (η_p² = 0.175/p < 0.001). ΔE00 was mainly influenced by the choice of ceramic (η_p² = 0.490/p < 0.001), the shade of resin composite (η_p² = 0.031/p = 0.012) as well as the interaction between ceramic and resin composite (η_p² = 0.258/p < 0.001).

Conclusions: RCC shades presented differential impacts on color change of CAD/CAM ceramics.

Clinical significance: Knowledge of the impact of available RCC shades on different CAD/CAM ceramics is crucial for an esthetic outcome and proper selection of ceramic restorations.

Keywords: CAD/CAM ceramic; CIEDE2000; CIELab; color change; optical properties; resin composite cement.