SEM evaluation of apical intraradicular dentine cleanliness and degree of erosion after the application of three irrigating solutions

Manuele Mancini, Luigi Cianconi

Department of Restorative Dentistry and Endodontics, University of Rome “Tor Vergata”, Rome, Italy.

DOI: 10.4236/ojst.2013.32030                

Abstract

Aims: The aim of the study was to compare the efficacy of 37% phosphoric acid, 12% nitric acid, 17% EDTA in endodontic smear layer removal and degree of erosion in the apical third of endodontic canals. Methods and Material: One hundred and four extracted single-rooted human teeth were randomized into four groups (n = 26) and instrumented using ProTaper Universal Ni-Ti rotary instruments. Each canal was irrigated with one of the following solutions: 37% phosphoric acid, 12% nitric acid, 17% EDTA, 5.25% NaOCl (control). All specimens were then irrigated with 5 mL distilled water and dried with sterile paper points. Kruskal-Wallis and Mann-WhitneyU statistical tests were used. Results: Scanning electron microscopy (SEM) evaluation showed no significant differences among test reagents in smear layer removal. However, the efficacy of 12% nitric acid and 17% EDTA in removing the smear layer was significantly greater than 5.25% NaOCl (control). Degree of erosion could not be evaluated. Conclusion: Protocols used in this study were not sufficient to completely remove the smear layer in the apical third of shaped root canals.

Keywords

EDTA; Nitric Acid; Phosphoric Acid; Irrigation; Smear Layer

Conflicts of Interest

The authors declare no conflicts of interest.

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