Effect of Sodium Ascorbate, Grape Seed Extract, and Aloe Vera Application after In-Office Bleaching on the Bond Strength of Enamel: A 3-Year Evaluation

Table 2

Microtensile bond strength (µTBS) values (means ± standard deviations) of the different experimental groups.

Experimental groups	Restauration moment	Storage time
		24 hr	3 years
Control (without bleaching)	Immediately	28.0 ± 2.8	31.4 ± 4.3
After bleaching (without antioxidants)	Immediately	22.5 ± 3.5^d; ≠	27.9 ± 3.0^b; =
	7 days after bleaching	23.5 ± 1.3^d; ≠	30.3 ± 5.9^ab; =
	14 days after bleaching	32.6 ± 3.2^a; =	31.0 ± 4.3^ab; =
After bleaching + sodium ascorbate 10%	Immediately	27.6 ± 2.6^b; =	28.1 ± 2.7^b; =
	7 days after bleaching	27.2 ± 2.9^bc; =	30.0 ± 5.7^ab; =
	14 days after bleaching	31.6 ± 1.6^ab; =	31.0 ± 4.3^ab; =
After bleaching + Aloe vera	Immediately	20.1 ± 1.7^d; ≠	27.8 ± 5.0^b; =
	7 days after bleaching	27.7 ± 2.3^bc; =	31.7 ± 1.4^ab; =
	14 days after bleaching	30.2 ± 4.5^b; =	31.8 ± 4.2^ab; =
After bleaching + grape seed extract	Immediately	21.8 ± 1.6^d; ≠	31.9 ± 4.4^ab; =
	7 days after bleaching	27.8 ± 1.3^b; =	34.6 ± 4.4^a; ≠
	14 days after bleaching	29.6 ± 1.6^b; =	31.3 ± 5.1^ab; =

() Similar letters mean statistically similar groups (3-way repeated measures ANOVA and Tukey test; ). The symbol ( = ) means similarity and the symbol (≠) difference compared to the control group for each time (Dunnett’s post hoc test, ). ( ) No significant difference was observed when the 24 hr control group was compared with the 3-year control group (t-test, ).