Table 1.

Comparison of mean dentinal tubule occlusion scores between different groups during using One-way ANOVA test.

Acid challenge	Groups	N	Mean	SD	Min	Max	P-value
Before acid challenge	Group 1	20	4.1	0.64	3	5	<0.001*
	Group 2	20	4.55	0.69	3	5
	Group 3	20	2.5	0.69	1	3
	Group 4	20	1.55	0.61	1	3
After acid challenge	Group 1	20	4.25	0.64	3	5	<0.001*
	Group 2	20	4.8	0.41	4	5
	Group 3	20	3.55	0.76	1	4
	Group 4	20	1.85	0.67	1	3