Antimicrobial and cytotoxic effects of phosphoric acid solution compared to other root canal irrigants

• Published in: Journal of applied oral science 2015-04, Vol.23 (2), p.158-163
• Main Authors: Prado, Maíra, Silva, Emmanuel João Nogueira Leal da, Duque, Thais Mageste, Zaia, Alexandre Augusto, Ferraz, Caio Cezar Randi, Almeida, José Flávio Affonso de, Gomes, Brenda Paula Figueiredo de Almeida
• Format: Article
• Language: English
• Subjects: Animals; Anti-Infective Agents - pharmacology; Bacteria - drug effects; Bacteria - growth & development; BALB 3T3 Cells; Candida albicans - drug effects; Candida albicans - growth & development; Cell Survival; Chlorhexidine; Chlorhexidine - pharmacology; Citric acid; Citric Acid - pharmacology; Colony Count, Microbial; Cytotoxins - pharmacology; Dentistry; DENTISTRY, ORAL SURGERY & MEDICINE; Edetic Acid - pharmacology; EDTA; Materials Testing; Mice; Microbial Sensitivity Tests; Original; Phosphoric acids; Phosphoric Acids - pharmacology; Products with antimicrobial action; Root Canal Irrigants - pharmacology; Sodium Hypochlorite - pharmacology; Time Factors; Toxicity test
• ISSN: 1678-7757; 1678-7765; 1678-7765; 1678-7757
• DOI: 10.1590/1678-775720130691

Phosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer. The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics. The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (solution and gel), and 5.25% NaOCl were evaluated. The antimicrobial activity was tested against Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Actinomyces meyeri, Parvimonas micra, Porphyromonas gingivalis, and Prevotella nigrescens according to the agar diffusion method. The cytotoxicity of the irrigants was determined by using the MTT assay. Phosphoric acid presented higher antimicrobial activity compared to the other tested irrigants. With regard to the cell viability, this solution showed results similar to those with 5.25% NaOCl and 2% chlorhexidine (gel and solution), whereas 17% EDTA and 10% citric acid showed higher cell viability compared to other irrigants. Phosphoric acid demonstrated higher antimicrobial activity and cytotoxicity similar to that of 5.25% NaOCl and 2% chlorhexidine (gel and solution).