To examine the change in color (ΔE) at different intervals over a week of four CAD/CAM block materials in three shades stored in red wine.
Method:
Five disks of each shade BL2, B1, and A3 (or most similar shade) of four CAD/CAM materials (Group 1 - Lava Ultimate, 3M ESPE; Group 2 - Vita Enamic, Vident; Group 3 - EmpressCAD and Group 4 - e.maxCAD, IvoclarVivadent) were sectioned and polished through 1200-grit SiC on both sides to a thickness of 1.0±0.05 mm. Specimens were stored in red wine (Loca Ciuca Chianti 2007) at 37°C. Each group of specimens were removed, steam cleaned, and measured using a Hunter Lab UltraScanVIS Spectrophotometer with a white background at baseline, 1hr, 6hrs, 12hrs, 24hrs, 3 days, and 7 days for CIE L*a*b* values. Using the CIE L*a*b* values, ΔE was calculated between baseline and each time interval for each disk of material/shade. Data was analyzed by one-way univariate analysis of variance (ANOVA), p < 0.05. Follow up multiple comparisons (Tukey HSD) were performed to examine material differences, time differences within each material, and sensitivity of each shade.
Result:
The ΔE values ranged from 1.09±0.21 (A3–1hr) to 4.77±0.51 (A3-7 days) for Group 1, 0.49±0.42 (B1–6hr) to 5.06±0.78 (BL2-7 days) for Group 2, 0.37±0.11 (BL2–6hr) to 1.83±0.63 (A3-7 days) for Group 3, and 0.59±0.39 (B1–3 days) to 2.94±0.64 (BL2-7days) for Group 4. Statistically significant differences were observed with respect to time for Groups 1 and 2 while only Group 4 BL2 had any differences in Groups 3 and 4. Shade BL2 was the most sensitive shade.
Conclusion:
Within the bounds of this study, Groups 1 and 2 had statistically higher ΔE values at most time/shade intervals. Shade BL2 was the most sensitive giving a statistical difference while shade B1 was the least.