title: Antimicrobial effect of endodontic solutions used as final irrigants on a dentine biofilm model.
abstract: OBJECTIVE
  To evaluate the residual biovolume of live bacterial cells, the mean biofilm thickness and the substratum coverage found in mixed biofilms treated with different endodontic irrigant solutions.
  
  
  METHODS
  Twenty-five bovine dentine specimens were infected intraorally using a removable orthodontic device. Five samples were used for each irrigant solution: 2% chlorhexidine, 1% sodium hypochlorite (NaOCl), 10% citric acid, 17% EDTA and distilled water. The solutions were used for 5 min. The samples were stained using the Live/Dead technique and evaluated using a confocal microscope. Differences in the amount of total biovolume (μm(3)), number of surviving cells (μm(3)), mean biofilm thickness (μm) and substratum coverage (%) of the treated biofilms were determined using nonparametric statistical tests (P < 0.05).
  
  
  RESULTS
  Similar values of biovolume total, biovolume of live subpopulations and substratum coverage were found in 2% chlorhexidine, 10% citric acid, 17% EDTA and distilled water-treated biofilms (P > 0.05). The lower values of the studied parameters were found in 1% NaOCl-treated dentine (P < 0.05) with the exception of the mean biofilm height criteria that did not reveal significant differences amongst the irrigant solutions (P > 0.05).
  
  
  CONCLUSIONS
  One per cent sodium hypochlorite was the only irrigant that had a significant effect on biofilm viability and architecture.
authors: Department of Endodontics, Dental School of Bauru, University of São Paulo, Bauru, Brazil. ronaldordinola@usp.br
authors: R
authors: R
authors: Ordinola-Zapata
authors: C M
authors: CM
authors: Bramante
authors: B
authors: B
authors: Cavenago
authors: M S Z
authors: MS
authors: Graeff
authors: I
authors: I
authors: Gomes de Moraes
authors: M
authors: M
authors: Marciano
authors: M A H
authors: MA
authors: Duarte
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects*; D002417:Cattle; D002614:Chelating Agents / Q000494:pharmacology; D002710:Chlorhexidine / Q000494:pharmacology; D019343:Citric Acid / Q000494:pharmacology; D004396:Coloring Agents; D003804:Dentin / Q000382:microbiology*; D004492:Edetic Acid / Q000494:pharmacology; D005456:Fluorescent Dyes; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D050296:Microbial Viability / Q000187:drug effects; D018613:Microscopy, Confocal; D009930:Organic Chemicals; D018704:Orthodontic Retainers; D011419:Propidium; D012388:Root Canal Irrigants / Q000494:pharmacology*; D012973:Sodium Hypochlorite / Q000494:pharmacology; D014867:Water
chemical_list: D000890:Anti-Infective Agents; D000891:Anti-Infective Agents, Local; D002614:Chelating Agents; D004396:Coloring Agents; D005456:Fluorescent Dyes; D009930:Organic Chemicals; D012388:Root Canal Irrigants; C103389:SYTO 9; D014867:Water; D019343:Citric Acid; D011419:Propidium; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D002710:Chlorhexidine