The effect of resin cement and background color on color of different ceramic CAD/CAM blocks

The final color of esthetic restorations depends on the backgrounds, thickness of the ceramic, the color of the underlying tooth, and the color of the composite resin cement. The aim of our thesis study was to evaluate the effect of the tooth-shaded composite background color, ceramic type and resin cement shade on the final color of thin restorations. Nanoceramic Cerasmart (GC Corp, Tokyo, Japan) and leucite reinforced feldspathic ceramic Initial LRF (GC Corp, Tokyo, Japan) CAD/CAM blocks with (A2/ HT) were used for ceramics specimens. Ceramic specimens (thickness 0.8 mm±0.02) were sliced at 400 rpm and under water cooling in the cutting device from the blocks. To represent the prepare teeth, tooth-shaded composite backgrounds (4 mm thickness) were obtained by using A1/A3 shaded composite resin. Ceramics were cemented to backgrounds using three different colors (neutral N; warm, W; and translucent, Tr) of try-in dual polymerized resin cement (Variolink II Try-In; Ivoclar-Vivadent, Germany) Color measurements were made with a spectrophotometer device. ∆E00 values was calculated using the values of L, a, b in each measurement, according to the formula CIEDE2000. ∆E00 values were evaluated statistically (p=0.05). In Initial LRF ceramic group, there was a significant difference between A1 and A3 backgrounds when light cement was used (p <0.05). There was no significant difference in other groups (p> 0.05). In conclusion, it was found that the material content had no effect on the final color of the restoration and the dark background resulted in more color change in thin ceramic restorations.