title: Evaluation of Antimicrobial and Antifungal efficacy of Chitosan as endodontic irrigant againstEnterococcus FaecalisandCandida AlbicansBiofilm formed on tooth substrate.
abstract: BACKGROUND
  Bacterial biofilms formed on the root canal wall are often difficult to remove. This study aimed to evaluate the cytotoxic effect and antibacterial efficacy of chitosan when used as root canal irrigant againstE. FaecalisandCandida albicansbiofilm formed on tooth substrate.
  
  
  METHODS
  The present study evaluated antibacterial effect of 0.25% Chitosan, 0.5% Chitosan, 2% chlorhexidine and 3% sodium hypochlorite againstEnterococcus faecalisandCandida Albicans. Agar-well diffusion methods, minimal inhibitory concentration tests and biofilm susceptibility assays were used to determine antibacterial activity. Teeth specimens were sectioned to obtain a standardized tooth length of 12mm. Specimens were inoculated with 10 mL of the freshly preparedE. Faecalissuspension andCandida albicansfor 4 weeks. The specimens were then instrumented with ProTaper rotary files F3 size. After irrigation with test solution, three sterile paper points were placed into one canal, left for 60 s and transferred to a test tube containing 1 mL of reduced transport fluid. The number of CFU in 1 mL was determined.
  
  
  RESULTS
  3-week biofilm qualitative assay showed complete inhibition of bacterial growth with 3% Sodium hypochlorite, 2% Chlorhexidine and Chitosan except saline, which showed presence of bacterial growth. Significant reduction of colony forming units (CFU)/mL was observed for the chitosan groups and the antibacterial activity of the chitosan groups was at par with 3% NaOCl and 2% Chlorhexidine. It was observed that the chitosan showed no cytotoxicity at 3mg/ml and 10% cytotoxicity at 6mg/ml.
  
  
  CONCLUSIONS
  The use of chitosan as a root canal irrigant might be an alternative considering the various undesirable properties of NaOCl and chlorhexidine.Key words:Biofilm, Candida albicans, Chitosan, Cytotoxicity, Enterococcus faecalis.
authors.affiliation: Senior Resident Associate Professor, Department of Conservative Dentistry and Endodontics, Maulana Azad Institute of Dental Sciences, New Delhi, India.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Yadav
authors.affiliation: Associate Professor, Department of Conservative Dentistry and Endodontics, Maulana Azad Institute of Dental Sciences, New Delhi, India.
authors.forename: Sarika
authors.initials: S
authors.lastname: Chaudhary
authors.affiliation: Professor Department of Microbiology, University of Delhi South Campus.
authors.forename: Rajendra K
authors.initials: RK
authors.lastname: Saxena
authors.affiliation: Professor and HOD Department of Conservative Dentistry and Endodontics, Maulana Azad Institute of Dental Sciences, New Delhi, India.
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Talwar
authors.affiliation: MDS, Senior resident, Department of conservative dentistry and endodontics, Maulana Azad Institute of Dental Sciences, New Delhi, India.
authors.forename: Sudha
authors.initials: S
authors.lastname: Yadav