title: Effectiveness of final decontamination protocols against Enterococcus faecalis and its influence on bond strength of filling material to root canal dentin.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effectiveness of final decontamination protocols against Enterococcus faecalis and their influence on bond strength of filling material to root canal dentin.
  
  
  METHODS
  Ninety root canals were enlarged with ProTaper system and inoculated with E. faecalis for 15days. Sixty samples were randomly divided into six groups (n=10) and subjected to following protocols: G1-distilled water(control), G2-2% chlorhexidine, G3-QMix, G4-6.5% grape seed extract, G5-photodynamic therapy with optical fiber and G6-photodynamic therapy without optical fiber. The percentage of bacterial reduction was checked by counting of CFUs. The remaining 30 samples were subjected to the same decontamination protocols (n=5) and filled with gutta-percha and AH Plus sealer in order to perform the push-out test. Data from both tests were subjected to one-way ANOVA followed by Tukey's post hoc procedure (α=0.05).
  
  
  RESULTS
  The greatest bacterial reduction was observed for 2% chlorhexidine, QMix and 6.5% grape seed extract, with no statistically significant difference between them. Photodynamic therapy, with and without optical fiber, demonstrated a significantly higher reduction than distilled water, with no statistically significant difference between them (p<0.05). For the push-out test, final decontamination protocols showed similar bond strength values (p<0.05), with the highest incidence of cohesive failure in all groups.
  
  
  CONCLUSIONS
  The tested final decontamination protocols showed effectiveness against E. faecalis and did not interfere with the bond strength of filling material to root canal dentin.
authors.affiliation: School of Dentistry, University of Passo Fundo, Passo Fundo, RS, Brazil. Electronic address: matheus292@yahoo.com.br.
authors.forename: Matheus
authors.initials: M
authors.lastname: Albino Souza
authors.affiliation: School of Dentistry, University of Passo Fundo, Passo Fundo, RS, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Dalla Lana
authors.affiliation: School of Dentistry, University of Passo Fundo, Passo Fundo, RS, Brazil.
authors.forename: Ezequiel
authors.initials: E
authors.lastname: Gabrielli
authors.affiliation: School of Dentistry of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil.
authors.forename: Marlos
authors.initials: M
authors.lastname: Barbosa Ribeiro
authors.affiliation: School of Dentistry, University of Passo Fundo, Passo Fundo, RS, Brazil.
authors.forename: Daniela Cristina
authors.initials: DC
authors.lastname: Miyagaki
authors.affiliation: School of Dentistry, University of Passo Fundo, Passo Fundo, RS, Brazil.
authors.forename: Doglas
authors.initials: D
authors.lastname: Cecchin
mesh_terms: D001645:Biguanides / Q000627:therapeutic use; D002470:Cell Survival; D002710:Chlorhexidine / Q000627:therapeutic use; D003666:Decontamination / Q000379:methods*; D003786:Dental Pulp Cavity / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000187:drug effects*; D056604:Grape Seed Extract / Q000627:therapeutic use; D006171:Gutta-Percha; D006801:Humans; D008422:Materials Testing; D010778:Photochemotherapy / Q000379:methods*; D011108:Polymers / Q000627:therapeutic use; D012388:Root Canal Irrigants / Q000627:therapeutic use*; D014867:Water
chemical_list: D001645:Biguanides; D056604:Grape Seed Extract; D011108:Polymers; C557698:QMix root canal irrigant; D012388:Root Canal Irrigants; D014867:Water; D006171:Gutta-Percha; D002710:Chlorhexidine
keywords: Bond strength; Enterococcus faecalis; Grape seed extract; Photodynamic therapy; QMix