Examination of color change after accelerated aging of glass ceramic crowns using zirconium cor and different cements

The aim of this study is to investigate the color changes in the same color, form and thickness of feldspatic glass ceramics (Cerec Blocs) crowns which cemented with 3 different dual-cure resin cements (Rely X U200, G-CEM LinkForce and Panavia V5) on zirconium cor after accelerated aging in the thermal cycler device. Using CAD / CAM system (Cerec AC), feldspatic glass ceramics (CerecBlocs) crowns that have thickness of 1 mm and 100 μ cement space and zirconium cors were produced. For each dual-cure cement, 15 samples were produced and a total of 45 crowns were produced. After 24 hours of cementation and after 1750, 3500 and 7000 thermal cycling aging, color measurments was performed separately for each sample with spectrophotometer (SpectroShade Micro). The color results obtained were calculated by CIEDE2000 color difference formulation and mean ΔE00 values of each research group were obtained. The minimum color change after 7000 thermal cycling aging occurred in samples of the Panavia V5 cement group (ΔE00: 0.97). While the average ΔE00 of Rely X U200 cement group samples was 1.08, in the G-CEM LinkForce siman group the mean ΔE00 was: 1.41. As the number of thermal cycles increased, the average ΔE00 value increased in all 3 dual cure cements. The fastest color difference occurred after 1750 thermal cycles. Color difference is slower after 3500 and 7000 thermal cycles. The absence of an amine agent in the content of Panavia V5 resin cement and the lack of benzoyl peroxide agent in the content of Rely X U200 resin cement resulted in the color being more stable in these cements.