Removal of smear layer by various root canal irrigations in primary teeth

Abstract

PurposeProper root canal irrigation is essential for endodontic treatment. To evaluate the effectiveness of several root irrigation regimens, the extent of the removal of smear layer from the root canal in primary teeth was analyzed. MethodsFifteen extracted human primary teeth were divided into five groups and subjected to the following irrigation regimes: Group 1, needle irrigation with saline; Group 2, needle irrigation with 5% sodium hypochlorite (NaOCl); Group 3, ultrasonic irrigation with 5% NaOCl; Group 4, needle irrigation with 14% ethylene diamine tetraacetic acid (EDTA); Group 5, ultrasonic irrigation with 14% EDTA. The percentage of open dentinal tubules (POD) in the irrigated root canal was analyzed using a scanning electron microscope. ResultsPOD for Groups 4 and 5 were significantly higher than Groups 1, 2, and 3 (p < 0.01, respectively). POD for Group 3 was significantly higher than Groups 1 and 2 (p < 0.01, respectively). By contrast, in Groups 4 and 5, erosive effects such as enlargement of orifices of dental tubules were observed. In Group 3, the smear layer was removed without erosion. ConclusionThese results suggest that root canal irrigation with NaOCl using an ultrasonic effectively removed smear layer from the root canal in primary teeth.