Influence of Cement Shades on the Color of Ceramic Laminates

Objectives: Obtaining optimal color of ceramic laminate veneers is a multifactorial process that involves many variables. The purpose of this in vitro study was to compare the color change resulting from cementing 2 shades of IPS-Empress all-ceramic material (translucent-T1 and opaque-O2) to 2 shades of XRV Herculite composite resin (light-A3 and dark-C4) using 2 shades of NX3 resin cement (clear-CL and yellow-Y). Methods: Forty ceramic disks (15x0.5 mm) were prepared, 20 for each shade. Additionally, 40 composite disks (15x4.0 mm) were fabricated, 20 for each shade. The ceramic and composite disks were luted using both shades of the resin cement try-in gel. The specimen combinations were divided into 8 groups (n=5). Color measurement was done using a colorimeter configured with diffuse illumination/0-degree viewing geometry. CIE lightness-L*, chroma-C_ab* and hue angle-h_ab* values were obtained. Results: Mean L*, C_ab*, and h_ab* are listed below:

Groups (n=5)          L*                 C_ab*                   h_ab*

T1-A3-CL       64.6 ± 0.7        7.3 ± 0.6          92.8 ± 1.4

T1-A3-Y         67.2 ± 0.5        9.1 ± 0.7          81.2 ± 1.7

T1-C4-CL       62.0 ± 0.3        6.6 ± 0.1          96.6 ± 1.1

T1-C4-Y         59.8 ± 0.4        6.9 ± 0.2          87.5 ± 0.8

O2-A3-CL      69.6 ± 1.2        6.0 ± 0.6          96.4 ± 1.7

O2-A3-Y         71.1 ± 0.3        7.8 ±0.3           83.7 ± 1.0

O2-C4-CL      67.5 ± 0.9        5.3 ± 0.5          97.7 ± 0.9

O2-C4-Y         65.6 ± 0.4        5.5 ± 0.2          89.6 ± 1.5

Three-way ANOVA and Tukey's Studentized range (HSD) Test (a=0.05) showed significant differences in L* and C_ab* for a change in composite and resin cement shades regardless of the ceramic shade. Conclusion: The color of 0.5 mm ceramic laminate veneers is significantly affected by the color change of the supporting substrate, as well as the luting resin cement. This study was supported in part by Kerr Corp. Orange, CA, USA.