title: Effect of chitosan-ethylenediamine tetraacetic acid on Enterococcus faecalis dentinal biofilm and smear layer removal.
abstract: OBJECTIVE
  The objective of the study was to evaluate the effectiveness of chitosan and chitosan-ethylenediamine tetraacetic acid (EDTA) (3:1,1:1,1:3) in comparison with 5.2% sodium hypochlorite (NaOCl) in disinfecting Enterococcus faecalis biofilm on root canal dentin and in the removal of smear layer with minimal erosion.
  
  
  METHODS
  Seventy single-rooted extracted human mandibular premolars (n = 70) were selected for the study. Forty tooth samples were biomechanically prepared, vertically sectioned, and sterilized by autoclaving. The tooth sections were artificially infected with E. faecalis (ATCC 29212 [n = 35] and clinical isolate [SBEF2, n = 35]) to form mature dentinal biofilm in vitro. The tooth samples were treated with the test solutions: chitosan and chitosan-EDTA (3:1, 1:1, 1:3), and the killing time was determined. The smear layer removal ability of the test solutions (Group A: chitosan-EDTA [1:1], Group B: EDTA, Group C: control) (n = 10 tooth/group) was assessed.
  
  
  RESULTS
  Chitosan and chitosan-EDTA (3:1, 1:1, 1:3) exhibited antibacterial activity against both the strains of E. faecalis. Chitosan and chitosan-EDTA caused 3 log reduction in the viable count of the sessile cells of E. faecalis at 15 min while 5.2% NaOCl exhibited 99.98% inhibition at 15 min. Chitosan-EDTA (1:1) was found to be effective in removing the smear layer and showed lesser erosion than EDTA at the coronal and middle portions.
  
  
  CONCLUSIONS
  Chitosan-EDTA (1:1) is a potential root canal irrigant that performs a dual role - root canal disinfection and smear layer removal.
authors.affiliation: Department of Conservative Dentistry and Endodontics, Sree Balaji Dental College and Hospital, BIHER, Bharath University, Chennai, Tamil Nadu, India.
authors.forename: Nagarajan
authors.initials: N
authors.lastname: Geethapriya
authors.affiliation: Department of Conservative Dentistry and Endodontics, Sree Balaji Dental College and Hospital, BIHER, Bharath University, Chennai, Tamil Nadu, India.
authors.forename: Arunajatesan
authors.initials: A
authors.lastname: Subbiya
authors.affiliation: Department of Microbiology, Research Laboratory for Oral and Systemic Health, Sree Balaji Dental College and Hospital, BIHER, Bharath University, Chennai, Tamil Nadu, India.
authors.forename: Kesavaram
authors.initials: K
authors.lastname: Padmavathy
authors.affiliation: Department of Microbiology, Research Laboratory for Oral and Systemic Health, Sree Balaji Dental College and Hospital, BIHER, Bharath University, Chennai, Tamil Nadu, India.
authors.forename: Krishnan
authors.initials: K
authors.lastname: Mahalakshmi
authors.affiliation: Department of Conservative Dentistry and Endodontics, Sree Balaji Dental College and Hospital, BIHER, Bharath University, Chennai, Tamil Nadu, India.
authors.forename: Paramasivam
authors.initials: P
authors.lastname: Vivekanandan
authors.affiliation: Department of Conservative Dentistry and Endodontics, Sree Balaji Dental College and Hospital, BIHER, Bharath University, Chennai, Tamil Nadu, India.
authors.forename: Virudhachalam Ganapathy
authors.initials: VG
authors.lastname: Sukumaran
keywords: Chitosan; Enterococcus faecalis; chitosan-ethylenediamine tetraacetic acid; dentinal biofilm; ethylenediamine tetraacetic acid