Aim: To analyze the shaping ability of Unicone (Medin), Wave One (Dentsply Maillefer) and Reciproc (VDW) reciprocating systems through the use of micro-computed tomography (MCT) in simulated curved canals. Methods: The shaping time, the centering ability and the changes in canal volumes of these systems were measured. Sixty artificial root canals with a curvature range of 300 in resin blocks, were scanned pre and postoperatively by MCT. The resin blocks were divided into four groups (n=15) and the root canals were shaped using three reciprocating systems and Ni-Ti Flex files (Dentsply Maillefer) for the control group. The data were analized using the software CTAnalyser and the Shapiro-Wilks test with p<0.05 indicating a statistically significant difference. Results: The results showed statistically significant difference (p<0.05) between the reciprocating and manual instruments regarding the shaping time. There was not statistically significant difference between the reciprocating systems used in this study. In the cervical portion of the canal, the Unicone system showed the highest volume increase of the reciprocating systems. No statistically significant diferences regarding the centering ability of the reciprocating systems were found. Conclusions: In comparison to the manual preparation technique, the reciprocating instruments provided a faster shaping of the simulated root canals and similar centering ability. Lastly, concerning the volume increase of the root canal portions, statistically significant differences in the cervical portion of the root canals were observed, identifying the highest values for the Unicone group within the reciprocating systems. Lastly, the reciprocating systems provided an adequate centering ability.