Antibacterial Effect of Different Concentration of Boric acid against Enterococcus Faecalis Biofilms in Root Canal

Recai ZAN, Ihsan HUBBEZOGLU, Ali Kemal OZDEMIR, Tutku TUNC, Zeynep SUMER, Oguzhan ALICI
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The aim of this study was to investigate the antibacterial effects of
different concentration of boric acid in root canals that were
infected with Enterococcus faecalis biofilms. 104 single-canal
premolar teeth were prepared and then disinfected and sterilized.
E.faecalis were inoculated into the root canals and kept at 37°C for
24 hours. The re-inoculation procedure was repeated on the first,
fourth, seventh and tenth days with fresh culture. The infected root
canals were divided into one negative (saline), one positive
(sodium hypochlorite) control group, and three experimental
groups (boric acid; 2%, 4% and 6%) (n=20). Paper points were
placed in root canals before and after irrigation to control and
evaluate the biofilm formation. Biofilms were counted on blood
agar plates, and the data were evaluated and statistically analyzed
using one-way ANOVA and Tukey’s test. There were statistically
significant differences among three experimental group (boric
acid; 2%, 4% and 6%). Although 6% concentration of boric acid
indicated the highest antibacterial effect, it could not exhibit the
same antibacterial effect as NaOCl. As a new product boric acid
indicated considerable bactericidal effect against E.faecalis
biofilms. However, the use of boric acid can be advisable with high
concentrations and long irrigation time for root canals disinfection.


Boric acid, root canal, microorganisms

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