Table 3. Surface roughness values (Ra) (median and 25%–75% values) of the tested groups.

Groups	Water				Coffee
	Baseline	1 week	6 weeks	p	Baseline	1 week	6 weeks	p
Control	0.15 (0.16–0.35)	0.17 (0.13–0.25)	0.18 (0.12–0.23)	0.476	0.17 (0.09–0.19)	0.18 (0.16–0.20)	0.19 (0.12–0.30)	0.586
Modeling Liquid	0.12 (0.08–0.19)	0.13 (0.08–0.16)	0.15 (0.12–0.27)	0.417	0.09 (0.07–0.12)*	0.10 (0.09–0.18)*	0.11 (0.08–0.14)*	0.528
Universal adhesive	0.13 (0.11–0.24)	0.15 (0.11–0.28)	0.18 (0.09–0.19)	0.607	0.14 (0.11–0.20)	0.15 (0.12–0.21)	0.15 (0.14–0.16)	0.788
Primer	0.20 (0.11–0.43)	0.27 (0.14–0.39)	0.28 (0.13–0.34)	0.939	0.18 (0.17–0.27)	0.18 (0.12–0.25)	0.21 (0.13–0.26)	0.649
p	0.086	0.131	0.223		0.027	0.024	0.029

^*Represents a significant difference among the groups in a column (p < 0.05).