Scanning electron microscopy evaluation of smear layer removal using ethylenediaminetetraacetic acid, etidronic acid, and chitosan nanoparticle solution as root canal irrigants

Aim: The purpose of this study is to evaluate and compare the efficacy of 17% EDTA, 18% etidronic acid, and 0.2% chitosan nanoparticle solution in smear layer removal using SEM image analysis. Methods: Thirty freshly extracted mandibular premolars were used. After biomechanical preparation, the samples were divided into Group I (17% EDTA), Group II (18% etidronic acid), and Group III (0.2% chitosan nanoparticle solution) containing 10 samples each. Longitudinal sectioning of the samples was done. The samples were observed under SEM at apical, middle, and coronal levels. The images were scored according to the criteria by Hullsman. Statistical analysis was done, with the significance level set at P < 0.05, and performed with SPSS 16.0 statistical package for Windows. Results: Smear layer removal at coronal, middle, and apical thirds was more effective when final irrigation was performed using 0.2% chitosan solution, followed by 17% EDTA. At the apical third, all the irrigants showed poor smear layer removing property, but chitosan showed comparatively better results. Conclusion: 0.2% chitosan nanoparticle solution was more effective in removing the smear layer when compared to 17% EDTA and 18% etidronic acid irrigants.