2004 Volume 25 Issue 2 Pages 72-76
Abstract : In this study, we observed the smear layer on root canal dentin after using the following hand instruments : a stainless steel K-file, an H-file, trial-manufactured H-files, and a trial-manufactured K-file, by SEM, and we also observed after application of 10% polyacrylic acid to those smear layers. With application of 10% polyacrylic acid for 20 seconds to those smear layers, dentinal plugs were not observed by SEM, except with use of a K-file and a trial-manufactured K-file. Therefore, it is considered that the H-file and the trial-manufactured H-file hardly created dentinal plugs in root canal shaping. It is suggested that EDTA is necessary to remove the smear layer and dentinal plug created using a K-file ; however, application of 10% polyacrylic acid for 20 seconds is sufficient to remove the smear layer created by an H-file or a trial-manufactured H-file.