The change of teeth color, whiteness variations and its psychosocial and self-perception effects when using low vs. high concentration bleaching gels: a one-year follow-up

Table 3 Comparison of ΔE values and Color change using CIEDE2000 formula, with data from the Vita Easyshade spectrophotometer measurements at different times expressed as mean and SD

Assessment points	Color change by ΔE			Color change by ΔCIEDE2000
Assessment points	37.5% Hydrogen Peroxide	6% Hydrogen Peroxide	Mann-Whitney test*	37.5% Hydrogen Peroxide	6% Hydrogen Peroxide	Mann-Whitney test*
Baseline vs. 1-wk after bleaching	8.67 ± 2.61	5.59 ± 3.41	0.000	5.10 ± 1.57	3.22 ± 1.90	0.000
Baseline vs. 1-mth after bleaching	9.05 ± 2.74	5.08 ± 2.11	0.000	5.37 ± 1.61	2.94 ± 1.15	0.000
Baseline vs. 6-mths after bleaching	8.01 ± 2.84	5.07 ± 2.98	0.001	4.73 ± 1.59	2.87 ± 1.61	0.000
Baseline vs. 12-mths after bleaching	8.37 ± 2.73**	5.27 ± 2.53**	0.000	4.92 ± 1.55**	3.07 ± 1.36**	0.000

* for comparison between both groups in each assessment time; ** for comparison between two assessment time (1-month vs 12-month after bleaching) in each group. No significant difference was found (Wilcoxon test; p > 0.05).** for comparison between two assessment time (1-month vs 12-month after bleaching) in each group. No significant difference was found (Student t test for paired sample; p > 0.05)

ISSN: 1472-6831