Table 1. Samples analyzed by SEM according to the residue presence.

Groups	N a	+ b	- c
Mtwo R/solvent	13	3	10
Mtwo R	10	2	8
ProTaper/solvent	9	1	8
ProTaper	10	4	6

^a N:total number

^b +:filling residue detected

^c -:filling residue not detected