Table 2 Descriptive values of ∆T of the retainer materials with different surface textures at difference times after staining – Mean (\(\pm\)SD)

Coffee

1.519

(0.690)

1.770 ^b,c

(0.210)

24.198 ^a,b,d

(6.224)

16.528 ^a,b,d

(5.422)

2.101 ^a,b,c (0.258)

23.466 ^a,b,d (6.543)

17.429 ^a,b,d (7.931)

Tea

0.952 ^a

(0.407)

0.901 ^a

(0.291)

20.183 ^a,b,d

(5.282)

20.368 ^a,b,d

(5.882)

1.190 (0.231)

25.190 ^a,b,d (2.162)

19.184 ^a,b,d (6.160)

Wine

1.055 ^a

(0.356)

1.130 ^a

(0.165)

1.176

(1.098)

1.563

(0.711)

1.051 (0.305)

2.281 ^a,d (1.654)

1.926 ^d (0.472)

Water

2.285

(0.459)

1.964

(0.258)

2.567

(0.439)

2.276

(0.533)

0.697 (0.264)

0.154

(0.674)

0.812 (0.281)