2022 Volume 43 Issue 3 Pages 164-171
Abstract : Purpose : This study aimed to evaluate the effectiveness of a sonic-powered irrigation system (EDDY) used in combination with ethylene diamine tetra acetic acid (EDTA) and sodium hypochlorite (NaOCl) on smear layer removal and dentinal erosion.
Materials and Methods : Noncarious human single-rooted teeth (n=60) were decoronated and their root canals were then prepared up to #40/.08 at a 10-mm working length. These root canals were irrigated with needles or EDDY with EDTA and NaOCl in various sequences and durations (n=5 each). The removal of the smear layer and the degree of dentinal erosion were assessed by scanning electron microscope observation. The percentage of smear layer covering the canal wall and dentin tubules was scored : score 1, smear layer almost absent ; score 2, 25% or less ; score 3, 25-50% ; score 4, 50-75% ; score 5, 75-100%. The degree of dentinal erosion was also scored : score 1, no erosion, all tubules look normal in appearance and size ; score 2, moderate erosion, the peritubular dentin is eroded ; score 3, severe erosion, the intertubular dentin is destroyed. The data were statistically analyzed by one-way ANOVA followed by a post-hoc Bonferroni test.
Results : The canal walls were consistently cleaner in the coronal and middle thirds than in the apical third in all specimens of the syringe irrigation groups. The 60 s EDDY irrigation removed more smear layer from the canal wall in the apical third than the 30 s EDDY irrigation and the 30 and 60 s syringe irrigations. The NaOCl with 60 s EDDY followed by EDTA with 60 s EDDY irrigation showed less dentinal erosion compared to the EDTA with 60 s EDDY followed by NaOCl with 60 s EDDY irrigation.
Conclusion : The NaOCl with 60 s EDDY followed by EDTA with 60 s EDDY irrigation is effective for smear layer removal and erosional inhibition from the root canal walls from the apical area to the coronal area.
