Effect of staining beverages and bleaching on optical properties of a CAD/CAM nanohybrid and nanoceramic restorative material

Table 2 Mean differences and standard deviations of whiteness indexes after staining (ΔWI_Dsti), bleaching (ΔWI_Dbl-st), and the residual difference compared to baseline (ΔWI_Dbl-i)

Staining solutions	CAD/CAM restorative materials
Staining solutions	LU	GR
ΔWI_Dst-i
Distilled water	− 0.06 ± 0.01^Aa	− 0.05 ± 0.02^Ba
Coffee	− 8.75 ± 1.33^Ab	− 7.91 ± 1.02^Bb
Tea	− 4.12 ± 0.96^Ac	− 3.37 ± 0.86^Bc
Cola	− 3.04 ± 0.49^Ac	− 3.08 ± 0.39^Ac
Ginger	− 2.18 ± 0.25^Ad	− 2.19 ± 0.27^Ad
ΔWI_Dbl-st
Distilled water	− 0.51 ± 0.06^Aa	− 0.46 ± 0.07^Ba
Coffee	5.23 ± 1.22^Ab	4.83 ± 0.89^Ab
Tea	2.41 ± 0.42^Ac	2.09 ± 0.59^Bc
Cola	1.62 ± 0.28^Ad	1.74 ± 0.26^Bc
Ginger	2.24 ± 0.44^Ac	1.17 ± 0.23^Bd
ΔWI_Dbl-i
Distilled water	− 0.45 ± 0.08^Aa	− 0.49 ± 0.08^Aa
Coffee	− 2.51 ± 1.04^Ab	− 2.48 ± 0.7^Ab
Tea	− 1.65 ± 0.41^Ab	− 1.09 ± 0.24^Bc
Cola	− 1.62 ± 0.21^Ab	− 1.41 ± 0.18^Bd
Ginger	− 0.64 ± 0.09^Ac	− 1.06 ± 0.19^Bc

Mean values represented with different superscript lowercase letter (column) are significantly different (P < 0.05)
Mean values represented with different superscript uppercase letter (row) are significantly different (P < 0.05)

ISSN: 1472-6831