Table 4.

Impression technique accuracy in the anterior and posterior regions using the Mann-Whitney U test

Techniques	Variables	Number of impressions	Median	Mean	SD	P value
Open tray	Anterior	13	0.04	0.0569	0.0497	0.360
	Posterior	27	0.03	0.0659	0.0737
Closed tray	Anterior	13	0.03	0.0515	0.0571	0.039*
	Posterior	27	0.04	0.1026	0.1013

*Significance level p ≤ 0.05