Do Different Tooth Bleaching–Remineralizing Regimens Affect the Bleaching Effectiveness and Enamel Microhardness In Vitro?

Table 3

The means and standard deviations of microhardness values among the experimental groups at three different depths of measurements.

Study groups	D1 (20–30 µm)	D2 (50–60 µm)	D3 (120–100 µm)	Repeated measurement analysis
NC	327.4 ± 52.0^aA	336.7 ± 49.4^aB	399.7 ± 44.1^aC	F = 60.8,
B	174.3 ± 35.9^bA	273.8 ± 24.0^bB	336.5 ± 13.9^bcC	F = 175.34,
FHA/B	230.9 ± 11.8^cA	284.0 ± 15.4^bB	324.9 ± 20.9^cC	F = 226.97,
FHA + B	256.5 ± 18.3^dA	329.1 ± 15.4^aB	356.4 ± 20.0^abC	F = 148.06,
B/FHA	253.7 ± 17.2^dA	338.2 ± 24.0^aB	359.0 ± 14.7^aC	F = 161.52,
NaF/B	268.4 ± 33.6^dA	342.5 ± 30.1^aB	362.0 ± 30.3^abC	F = 210.57,
NaF + B	271.7 ± 48.8^acdA	345.4 ± 39.1^aB	364.6 ± 34.4^abC	F = 156.14,
B/NaF	283.4 ± 41.1^adA	348.1 ± 22.8^aB	362.8 ± 16.9^aC	F = 87.83,
One-way analysis of variance	F = 20.17,	F = 15.65,	F = 9.02,	Interaction F = 11.55,

The different lowercase superscript letters in the columns indicate statistically significant differences at . The different uppercase superscript letters in the rows indicate statistically significant differences at .