Table 4: Analysis of the apical measurement.

-	Expert		Unexpert
-	IG-File	K-NiTi	IG-File	K-NiTi
Correct measurement	27 (90%)	10 (33.3%)	27 (90%)	8 (26.7%)
Overestimation	2 (6.7%)	3 (10%)	--	7(23.3%)
Underestimation	1 (3.3%)	17 (56.7%)	3 (10%)	15(50%)