J Dent Res Dent Clin Dent Prospects. 2017;11(4): 215-221.
doi: 10.15171/joddd.2017.038
PMID: 29354247
PMCID: PMC5768953
Scopus ID: 85056532701
  Abstract View: 1026
  PDF Download: 811
  Full Text View: 631

Basic Research

Original Article

Antibacterial effect of different concentrations of sodium hypochlorite on Enterococcus faecalis biofilms in root canals

Mohammad Forough Reyhani 1, Yousef Rezagholizadeh 1*, Mohammad Reza Narimani 2, Lotfollah Rezagholizadeh 3, Mohammad Mazani 3, Mohammad Hossein Soroush Barhaghi 4, Yavar Mahmoodzadeh 3

1 Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
2 Iranian Center of Excellence in Health Management, Tabriz University of Medical Sciences, Tabriz, Iran
3 Department of Biochemistry, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
4 Department of Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
*Corresponding Author: *Corresponding Author; , Email: reza34055@gmail.com


Background. The aim of this study was to evaluate the effectiveness of different concentrations of sodium hypochlorite (NaOCl) solution in reducing bacterial growth in Enterococcus faecalis biofilms in root canals.

Methods. The root canals of maxillary central incisors of 104 subjects underwent chemomechanical debridement. In order to remove the smear layer, 5.25% sodium hypochlorite solution was used for 3 minutes in the root canals. Then, the samples were immersed in 1 mL of 17% EDTA for 3 minutes. Finally, the root canals were irrigated with phosphate-buffered saline (PBS) solution. After removing the smear layer, the samples were sterilized. Then E. faecalis biofilms formed within the root canals at 4-, 6-, and 10-week intervals were evaluated. Each group was divided into 4 subgroups in terms of the antibacterial treatment: group 1: 1% NaOCl solution; group 2: 2.5% NaOCl solution; group 3: 5.25% NaOCl solution; and group 4: PBS solution. After preparation of root canal filings, the counts of live bacteria were calculated through the classic method of counting, i.e. colony forming units (CFU), followed by the analysis of data.

Results. In groups 2 and 3, there was no bacterial growth due to complete removal of E. faecalis biofilms (P<0001), while the bacterial counts in group 1 at 4-, 6- and 10-week intervals decreased compared to the control group.

Conclusion. The bacterial cells in mature and old biofilms have higher resistance to 1% NaOCl solution compared to the young biofilms. However, the 2.5% and 5.25% NaOCl solutions caused complete inhibition of the growth of E. faecalis biofilm in all the stages of development.

First Name
Last Name
Email Address
Security code

Abstract View: 1027

Your browser does not support the canvas element.

PDF Download: 811

Your browser does not support the canvas element.

Full Text View: 631

Your browser does not support the canvas element.

ePublished: 19 Dec 2017
EndNote EndNote

(Enw Format - Win & Mac)

BibTeX BibTeX

(Bib Format - Win & Mac)

Bookends Bookends

(Ris Format - Mac only)

EasyBib EasyBib

(Ris Format - Win & Mac)

Medlars Medlars

(Txt Format - Win & Mac)

Mendeley Web Mendeley Web
Mendeley Mendeley

(Ris Format - Win & Mac)

Papers Papers

(Ris Format - Win & Mac)

ProCite ProCite

(Ris Format - Win & Mac)

Reference Manager Reference Manager

(Ris Format - Win only)

Refworks Refworks

(Refworks Format - Win & Mac)

Zotero Zotero

(Ris Format - Firefox Plugin)