RESUMEN
The aim of this study was to compare in vitro the debridement ability of Canal Master and K-Files using scanning electron microscope. One hundred and twelve freshly extracted human upper central incisor teeth were divided into two groups of 56 each. One group was instrumented using Canal Master and another group was instrumented using K-Files. The teeth were sectioned longitudinally and examined under the SEM. Scanning electron micrographs were qualitatively and statistically analysed for the degree of cleanliness with regard to the presence of debris, smeared layer and patency of dentinal tubules in the apical third of each root canal. In order to determine whether there is a difference between the two instrumentation techniques, a chi-square test of equal proportions was used. This test gave a chi-square value of 24.19 (P < .001). Both the instrumentation techniques were ineffective in completely debriding the canals. However, the results showed that the Canal Master produced cleaner showing lesser debris than that produced by K-Files.