Method: Shades were selected from two flowable composites, A1, A3, and White (WH), Filtek Supreme Ultra Flowable/3M ESPE (FSU); A1, A3 and Bleach (BL), Tetric EvoFlow/Ivoclar Vivadent (TEF), and A1, A3, and B1 micro-hybrid control (Filtek Z250/3M ESPE). Disc shaped specimens (10 mm X 2 mm, n=60) were polymerized using a halogen curing light (Demetron 501, Kerr/Demetron) for 40 seconds. Specimens were finished using 400-grit SiC paper and polished with a one-step polisher (PoGo, Dentsply/Caulk) for 40 seconds. Color measurements were taken at baseline (after 24 hour-storage in distilled water at 37°C) using a spectrophometer (Color-Eye 7000, GretagMacbeth) and after exposure to accelerated aging (150 kJ/m2) in a Weather-ometer (Ci35A, Atlas). Means and standard deviations were determined. The data were analyzed by analysis of variance. Fisher's PLSD intervals at a 0.05 level of significance were determined for mean Lab and ΔE values.
Result: Color parameter changes are listed in the following table,(composite product/shade):
|
TEF/A1 |
TEF/A3 |
TEF/BL |
FSU/A1 |
FSU/A3 |
FSU/WH |
Z250/A1 |
Z250/A3 |
Z250/B1 |
ΔL* |
-1.0(0.3) |
-0.6(0.4) |
-0.3(1.2) |
1.1(0.4) |
0.4(0.4) |
2.0(0.7) |
1.3(0.2) |
1.8(0.7) |
3.2(0.2) |
Δa* |
-0.2(0.1) |
0.2(0.1) |
-0.4(0.1) |
-0.3(0.0) |
-0.6(0.2) |
-0.2(0.3) |
-0.6(0.0) |
-0.5(0.0) |
0.4(0.0) |
Δb* |
0.4(0.4) |
-0.6(0.2) |
-0.5(0.4) |
-3.9(0.3) |
-3.4(0.9) |
-4.6(0.6) |
-0.8(0.2) |
-0.2(0.7) |
0.1(0.2) |
ΔE* |
1.2(0.3) |
0.9(0.3) |
1.3(0.3) |
4.0(0.2) |
3.5(0.8) |
5.1(0.8) |
1.6(0.2) |
2.0(0.7) |
3.2(0.2) |
Fisher's PLSD intervals for comparisons among products and shades were 0.4 for ΔL and ΔE while the corresponding values for Δa values were 0.09. The data showed significant ΔE* and ΔL* main effects for composite product and shades (p<0.001) and interactions (p=0.008 and p=0.03), respectively.
Conclusion: The effects of accelerated aging on color of resin flowable composites are dependent on composite product and shade selection. Tetric EvoFlow displayed the smallest aging-dependent color shift followed by Filtek Z250 and Filtek Supreme Ultra Flowable.
Products supplied by Ivoclar Vivadent.
Keywords: Aging, Color, Composites and Gloss
See more of: Dental Materials 11: Color and Appearance (Esthetics)