Table 3. Comparison of in-office and at-home bleaching by different color coordinates of CIEL*a*b* system, ΔE00 and ΔSGU.

Tooth color parameters	Evaluation period	In-office bleaching	At-home bleaching	P value
ΔL	Final	1.73 (3.29)	0.79 (3.99)	0,159
	2 weeks-post bleaching	-0.14 (6.50)	0.91 (5.36)	0,173
Δa	Final	0.33 (1.54)	-0.09 (1.42)	0.014*
	2 weeks-post bleaching	-0.13 (1.67)	-0.13 (1.25)	0,176
Δb	Final	-2.16 (2.68)	-3.55 (5.89)	0.003*
	2 weeks-post bleaching	-2.99 (2.59)	-4.25 (4.19)	0.037*
ΔE00	Final	4.03 (1.77)	4.33 (2.35)	0,083
	2 weeks-post bleaching	4.01 (1.02)	4.27 (1.59)	0,033
ΔSGU	Final	-3.00 (2.18)	-3.5 (2.27)	0,669
	2 week-post bleaching	-3.00 (2.17)	-4.00 (2.29)	0,445

* Differences were considered statistically significant when p<0.05. Mann Whitney test was applied for statistical comparison.