. 2020 Sep 8;14(4):525–532. doi: 10.1055/s-0040-1713058

Table 2. Mean values (SDs) of ∆E* of white group in each concentration over aging period.

∆ E	12 h	24 h	48 h	72 h
Group	12 h	24 h	48 h	72 h
Abbreviation: SD, standard deviation. Note: Tukey test with a level of significance of 0.05. Groups with the same superscript uppercase letter per column or lowercase letter per row are not significantly different ( p > 0.05). ^a Values of ∆ E * > 1.0a.
White - control	0.60 (.07) Aab	0.54 (0.06) Bab	0.98 (0.06) Cab	1.12 ^a (0.06) Cab
White - 0.5% ZnO	0.40 (0.05) Aab	0.51 (0.10) Bab	0.90 (0.06) Cab	1.13 ^a (0.05) Cab
White - 1.0% ZnO	0.55 (0.06) Aa	0.63 (0.07) Ba	1.10 (0.08) Ca	1.1 ^a (0.06) Ca
White - 1.5% ZnO	0.41 (0.06) Ab	0.58 (0.04) Bb	0.73 (0.05) Cb	0.78 (0.04) Cb
White - 2.0% ZnO	0.41 (0.05) Aa	0.76 (0.04) Ba	1.0 (0.06) Ca	1.10 ^a (0.06) Ca