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VOLUME 23 , ISSUE 10 ( October, 2022 ) > List of Articles


Antibacterial Efficacy of Irrigants with Varying Osmolarity on E. faecalis Biofilm: An In Vitro Study

Pradeeba Anandi Jeya Goutham, Arathi Ganesh, C Benedict Paul

Keywords : Chlorhexidine, Hyperosmotic salt solution, Hypoosmotic salt solution, Irrigants, Osmolarity, Povidone iodine, Root canal disinfection, Sodium hypochlorite

Citation Information : Goutham PA, Ganesh A, Paul CB. Antibacterial Efficacy of Irrigants with Varying Osmolarity on E. faecalis Biofilm: An In Vitro Study. J Contemp Dent Pract 2022; 23 (10):998-1003.

DOI: 10.5005/jp-journals-10024-3417

License: CC BY-NC 4.0

Published Online: 07-03-2023

Copyright Statement:  Copyright © 2022; The Author(s).


Aim: To evaluate the role of the addition of different concentrations of sodium chloride salt to conventional intracanal irrigants to vary their osmotic values and thereby compare their antibacterial efficacy. Materials and methods: In an active attachment biofilm model, Enterococcus faecalis (ATCC 29212) biofilms were grown. Sodium chloride salts were added to 100 mL of distilled water to make 6M (hyperosmotic), 0.5M, and 0.25M (hypoosmotic) sodium chloride solutions, respectively. The experimental groups were divided into three groups: Group I: 5.25% sodium hypochlorite, group II: 2% chlorhexidine, and group III: 2% povidone iodine, and four subgroups within these three groups, such as subgroup A (without salt solution), subgroup B (with 6M of hyperosmotic salt solution), subgroup C (with 0.5M of hypoosmotic salt solution), and subgroup D (with 0.25M of hypoosmotic salt solution), respectively. Biofilms were treated with all the subgroups for a contact time of 15 min. A crystal violet assay was done to estimate the bacterial cell biomass. Results: The results revealed that subgroups IIIB, IB, and IID, ID had a statistical reduction in bacterial biomass at p < 0.05. There were no significant differences between subgroups IC, IIC, and IIIC and subgroups IA, IIA, and IIIA. Conclusion: The antibacterial efficacy of all three irrigants was significantly affected by varying the osmolarities. Clinical significance: The results prove that the hyperosmotic and hypoosmotic salt solutions, along with irrigants, have enhanced antibacterial efficacy on E. faecalis biofilm due to its ability to vary the turgor pressure of cell wall, as well as the inherent properties of the irrigants such as hypochlorous acid formation, ionic interaction, and free radical interactions.

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