Table 3. Mean ΔE values and standard deviations for each specimen.
| Zirconia | Lithium disilicate | |||||
|---|---|---|---|---|---|---|
| Background | Thickness (mm) | Shade (3Y) | Shine T (4Y) | High shine (5.5Y) | Rosetta SM (LS) | P-value for ANOVA |
| ND3 | 0.8 | 2.52 ± 0.14 a | 2.68 ± 0.12 a | 2.72 ± 0.31 a | 3.39 ± 0.25 b | < .001 |
| ND9 | 0.8 | 7.98 ± 0.06 a | 8.25 ± 0.32 a | 9.28 ± 0.32 b | 11.75 ± 0.28 c | < .001 |
| Ti | 0.8 | 4.88 ± 0.11 a | 5.36 ± 0.11 b | 6.21 ± 0.26 c | 7.01 ± 0.29 d | < .001 |
| ND3 | 1.5 | 2.37 ± 0.41 a | 2.61 ± 0.21 a | 2.69 ± 0.25 a | 2.36 ± 0.14 a | .02 |
| ND9 | 1.5 | 6.05 ± 0.36 a | 6.57 ± 0.29 b | 7.61 ± 0.17 c | 7.9 ± 0.31 c | < .001 |
| Ti | 1.5 | 4.09 ± 0.64 a | 4.33 ± 0.29 a | 5.11 ± 0.18 b | 4.71 ± 0.14 b | < .001 |
*Under the same conditions, the same superscription indicates that there is no statistical difference in the mean value (P > .05).
**Letters a,b,c,d mean statistically significant differences between groups (P < .05).
***3Y (3 mol% yttria tetragonal zirconia polycrystals), 4Y (4 mol% yttria partially stabilized zirconia), 5.5Y (5.5 mol% yttria partially stabilized zirconia), LS (lithium disilicate).
****ND3 and ND9 of tooth-colored resin substrates to imitate standard dentin (ND3) and severely discolored dentin (ND9), Ti (milled Ti-6Al-4V alloy to imitate titanium abutment).