A comparative study of smear layer removal and erosion in apical intraradicular dentine with three irrigating solutions: a scanning electron microscopy evaluation

Introduction: This study compared the efficacy of BioPure MTAD (Dentsply Tulsa, Tulsa, OK), 17% EDTA, and 42% citric acid in endodontic smear layer removal and degree of erosion in the apical third of endodontic canals. Methods: Ninety-six extracted single-rooted human teeth were randomized into four groups (n = 24) and instrumented using System GT nickel-titanium rotary instruments (Dentsply Tulsa, Tulsa, OK). Each canal was irrigated with one of the following solutions: BioPure MTAD, 17% EDTA, 42% citric acid, or 5.25% NaOCl (control). Next, all specimens were irrigated with 5.25% NaOCl. Results: Evaluation by scanning electron microscopy showed no significant differences among test irrigants in removing the smear layer. However, the efficacy of BioPure MTAD and 17% EDTA in removing the smear layer was significantly greater than 5.25% NaOCl (control). The erosive effects of irrigating solutions could not be evaluated. Conclusions: In conclusion, the protocols used in this study were not sufficient to completely remove the smear layer in the apical third of prepared root canals. © 2009 American Association of Endodontists

Microstructural analysis of apical third after treatment with MTAD: an in vitro study

Aim: the goal of current endodontic treatment is to thouroughly clean, shape and tri-dimensionally obdurate root canals. The aim of the present in vitro study was to evaluate how acid pretratment of root surface can be an useful procedure for the above mentioned results.Methodology: the present in vitro study evaluated the microstructural acyion of MTAD, applied for 1,3 or 5 minutes, on root canal walls. The study was performed using SEM analysis and each specimen was judged accordin to a specific score which comprised both intra and peritubular cleanness and erosion of wall surfaces. Results. results showed that the use of MTAD did not allow perfect cleaning of the endodontic space and smear layer was still present. However a stastically significant differenced was noted among the test and control groups. Conclusions:MTAD showed a positive clinical action supporting the cleaning effect due to NaOCl irrigating solutions, but still complete elimination of smear layer was not obtained. As a result, ideal cleaning of the endodontic space is still not available with current materials and techniques