Bactericidal activity of phosphoric acid, citric acid, and EDTA solutions against Enterococcus faecalis.
OBJECTIVE
The objectives of this study were to evaluate the minimal bactericidal concentration (MBC) for Enterococcus faecalis of phosphoric acid, citric acid, and ethylenediaminetetraacetic acid (EDTA) solutions, and to determine the contact time required for 2.5% and 5% phosphoric acid, 10% and 25% citric acid, and 17% EDTA to exert bactericidal activity.


METHODS
Bactericidal activity was tested by means of the dilution neutralization method in accordance with BS-EN-1040:2005 norm, using contact times of 0.5 to 60 minutes.


RESULTS
The MBCs of citric and phosphoric acid were 20% and 2.5%, respectively. EDTA solution lacks bactericidal activity, even after 60 minutes of contact. The 2.5% and 5% phosphoric acid solutions required 5- and 3-minute contact times, and the 10% and 25% citric acid solutions required 10- and 3-minute contact times, respectively.


CONCLUSIONS
Phosphoric acid revealed bactericidal activity against E. faecalis and required less time than citric acid to exert its activity.
Department of Operative Dentistry, Faculty of Dentistry, University of Granada, Spain.
María Teresa
MT
Arias-Moliz
Carmen María
CM
Ferrer-Luque
Elena
E
Espigares-Rodríguez
José
J
Liébana-Ureña
Miguel
M
Espigares-García
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002614:Chelating Agents / Q000008:administration & dosage / Q000494:pharmacology; D019343:Citric Acid / Q000008:administration & dosage / Q000494:pharmacology*; D004492:Edetic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D013293:Enterococcus faecalis / Q000187:drug effects*; D006801:Humans; D008422:Materials Testing; D008826:Microbial Sensitivity Tests; D010756:Phosphoric Acids / Q000008:administration & dosage / Q000494:pharmacology*; D012388:Root Canal Irrigants / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
D000900:Anti-Bacterial Agents; D002614:Chelating Agents; D010756:Phosphoric Acids; D012388:Root Canal Irrigants; D019343:Citric Acid; D004492:Edetic Acid; C030242:phosphoric acid