Biofi lm forming capacity of Enterococcus faecalis on Gutta-percha points treated with four disinfectants using confocal scanning laser microscope: An in vitro study

Abstract

Background: The aim of this study was to evaluate and compare the in vitro biofi lm forming capacity

of Enterococcus faecalis on Gutta-percha points disinfected with four disinfectants.

Materials and Methods: A total of 50 Gutta-percha points used in this study were divided into

four test groups based on disinfectant (5.25% sodium hypochlorite, 2% chlorhexidine gluconate, 20%

neem, 13% benzalkonium chloride [BAK]), and one control group. The Gutta-percha points were

initially treated with corresponding disinfectants followed by anaerobic incubation in Brain Heart

Infusion broth suspended with human serum and E. faecalis strain for 14 days. After incubation,

these Gutta-percha points were stained with Acridine Orange (Sigma – Aldrich Co., St. Louis, MO,

USA) and 0.5 mm thick cross section samples were prepared. The biofi lm thickness of E. faecalis

was analyzed quantitatively using a confocal scanning laser microscope. Results statistically analyzed

using analysis of variance. P < 0.05 was considered to be signifi cant.

Results: Confocal scanning laser microscope showed reduced amount of E. faecalis biofi lm on Guttapercha

points treated with BAK and sodium hypochlorite. Post-hoc (least square differences) test revealed

that there is no statistically signifi cant difference between BAK and sodium hypochlorite groups (P > 0.05).

Conclusion: This study illustrates that the Gutta-percha points disinfected with sodium hypochlorite

and BAK showed minimal biofi lm growth on its surface.

Key Words: Benzalkonium chloride, biofi lm, chlorhexidine gluconate, confocal scanning laser microscope, Enterococcus faecalis, sodium hypochlorite