Summary. Nine endodontic instruments from different manufacturers (Reamers, K‐files, Hedstrom files, K‐FIex files, Flexofiles, S‐files, Burns Unifiles, Flexicut files and Flex‐R files) were used to prepare 180 simulated root canals in resin blocks. The instrument's ability to reproduce a theoretical pre‐established ideal canal shape was assessed by comparing the original canal path with the resulting enlarged canal shape by a double exposure photographic method. The individual ability of each instrument to transport debris was also observed during instrumentation under a stereomicroscope. Regardless of the instrument type, none was able to reproduce ideal results; however, clinically acceptable results could be obtained with all of them. The coronal and apical debris transportation characteristics proved to be similar with all instruments.