Influence of Irrigation with NaOCl and Chlorhexidine on Microleakage

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1 / Christos Gogos1 / Nikolaos Economides1

1Aristotle University of Thessaloniki, School of Dentistry, Department of Endodontology, Thessaloniki, Greece


Background: Irrigation during endodontic therapy is required in order to remove debris, tissue remnants, microbes and smear layer. Sodium hypochlorite (NaOCl) and Chlorhexidine (CHX) are the most commonly used irrigants. Although they are reported to have good antimicrobial effects, both have limitations. Hence, a combination of NaOCl and CHX has been proposed to compensate for these limitations. However, this association forms a dense, orange-brown precipitate that stains walls of the pulp chamber. The aim of this study was to clarify in vitro if this precipitate affects the microleakage of endodontic sealers.

Material and Methods: Extracted human teeth were used for this study. The teeth were cut at the height of the cervix and instrumented with NiTi rotary instruments. They were then divided into 2 experimental groups. In the first group (Group A) irrigations were performed with 2ml NaOCl 1%, 1ml EDTA 17% and 1ml CHX 0.2% and in the second (Group B) with 2ml NaOCl and 2ml CHX. Following this, they were obturated with gutta-percha and roth sealer. The microleakage was determined using a fluid filtration method. The measurements were repeated a month later. All analyses were performed using Fisher exact test.

Results: Microleakage of Group A was lower than microleakage of Group B but the difference was not statistically significant.

Conclusion: The precipitate that is formed by NaOCl and CHX did not affect microleakage of endodontic sealers.

Keywords: Irrigation; Precipitate; Microleakage; Sodium hypochlorite; Chlorhexidine


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Citation Information: Balkan Journal of Dental Medicine. Volume 19, Issue 1, Pages 38–42, ISSN (Online) 2335-0245, DOI:, July 2015