. 2018 Oct 2;26:e20170589. doi: 10.1590/1678-7757-2017-0589

Table 3. Mean values and standard deviations of relative areas of carbonate (CO₃ ^2-) peak V3 (1070 cm^-1) (in arbitrary units) of FT-Raman spectra of sound and demineralized enamel at baseline (T₀) and after bleaching (T_b).

Treatments	Sound enamel				Demineralized enamel
	T₀		T_b		T₀		T_b
C	3.66	(0.16)^Aa	5.51	(0.22)^Ab	2.19	(0.32)^Aa ^*	5.39	(0.56)^Ab ^*
HP	3.56	(0.29) ^Aa	3.13	(0.24)^Ba	1.95	(0.44)^Aa ^*	4.11	(0.31)^Bb ^*
HPF	3.57	(0.15) ^Aa	5.23	(0.47)^Ab	1.97	(0.28)^Aa ^*	5.42	(0.63)^Ab
HPC	3.49	(0.21) ^Aa	6.55	(0.89)^Ab	2.07	(0.77)^Aa ^*	5.38	(0.88)^Ab

Mean values followed by distinct letters differ statistically at 5%, according to three-way ANOVA and Tukey test (p<0.05). Uppercase letters compare treatments (in columns) and lowercase letters compare time (in row).

Asterisks (*) compare each enamel condition within time

C: control

HP: 35% hydrogen peroxide

HPF: fluoride-based bleaching agent containing 35% hydrogen peroxide

HPC: calcium-based bleaching agent containing 35% hydrogen peroxide

Table 3. Mean values and standard deviations of relative areas of carbonate (CO3 2-) peak V3 (1070 cm-1) (in arbitrary units) of FT-Raman spectra of sound and demineralized enamel at baseline (T0) and after bleaching (Tb).

Table 3. Mean values and standard deviations of relative areas of carbonate (CO₃ ^2-) peak V3 (1070 cm^-1) (in arbitrary units) of FT-Raman spectra of sound and demineralized enamel at baseline (T₀) and after bleaching (T_b).