Table 1.

The mean and standard deviation of Ra and Rz (μm) of all subgroups affected by different surface treatment methods and coloring techniques

Variable	Surface treatment method	Coloring technique
		White	Internal staining	External staining
Ra	Unpolished	1.01±0.19Aa	0.89±0.36Aab	0.45±0.5Ab
	Shofu polishing system	0.1±0.01Cb	0.21±0.04Ba	0.08±0.01Ab
	Dental direct polishing system	0.07±0.02Ca	0.15±0.17Ba	0.07±0.01Aa
	Glazing	0.44±0.13Bab	0.58±0.43ABaBa	0.17±0.08Ab
Rz	Unpolished	4.7±0.61Aa	4.25±1.4Aa	3.54±0.61Aa
	Shofu polishing system	0.42±0.07BCb	1.15±0.21Ca	0.31±0.08Cb
	Dental direct polishing system	0.3±0.1Ca	0.43±0.17Ca	0.29±0.09Ca
	Glazing	0.92±0.02Bb	2.7±1.1Ba	0.88±0.08Bb

Different superscript capital letters in each column and lower case letters in each row indicate statistically significantly difference (P<0.05)