title: Antimicrobial activity of triantibiotic paste, 2% chlorhexidine gel, and calcium hydroxide on an intraoral-infected dentin biofilm model.
abstract: BACKGROUND
  The purpose of this study was to evaluate the antimicrobial activity of calcium hydroxide, 2% chlorhexidine gel, and triantibiotic paste (ie, metronidazole, minocycline, and ciprofloxacin) by using an intraorally infected dentin biofilm model.
  
  
  METHODS
  Forty bovine dentin specimens were infected intraorally using a removable orthodontic device in order to induce the biofilm colonization of the dentin. Then, the samples were treated with the medications for 7 days. Saline solution was used as the control. Two evaluations were performed: immediately after the elimination of the medication and after incubation in brain-heart infusion medium for 24 hours. The Live/Dead technique (Invitrogen, Eugene, OR) and a confocal microscope were used to obtain the percentage of live cells. Nonparametric statistical tests were performed to show differences in the percentage of live cells among the groups (P < .05).
  
  
  RESULTS
  Calcium hydroxide and 2% chlorhexidine gel did not show statistical differences in the immediate evaluation. However, after application of the brain-heart infusion medium for 24 hours, 2% gel chlorhexidine showed a statistically lesser percentage of live cells in comparison with calcium hydroxide. The triantibiotic paste significantly showed a lower percentage of live cells in comparison with the 2% chlorhexidine gel and calcium hydroxide groups in the immediate and secondary (after 24 hours) evaluations.
  
  
  CONCLUSIONS
  The triantibiotic paste was most effective at killing the bacteria in the biofilms on the intraorally infected dentin model in comparison with 2% chlorhexidine gel and calcium hydroxide.
authors.affiliation: Department of Endodontics, Bauru Dental School of Bauru, University of São Paulo, Brazil. ronaldordinola@usp.br
authors.forename: Ronald
authors.initials: R
authors.lastname: Ordinola-Zapata
authors.forename: Clovis M
authors.initials: CM
authors.lastname: Bramante
authors.forename: Paloma Gagliardi
authors.initials: PG
authors.lastname: Minotti
authors.forename: Bruno Cavalini
authors.initials: BC
authors.lastname: Cavenago
authors.forename: Roberto Brandão
authors.initials: RB
authors.lastname: Garcia
authors.forename: Norberti
authors.initials: N
authors.lastname: Bernardineli
authors.forename: David E
authors.initials: DE
authors.lastname: Jaramillo
authors.forename: Marco A
authors.initials: MA
authors.lastname: Hungaro Duarte
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D058491:Bacterial Load / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects*; D002126:Calcium Hydroxide / Q000627:therapeutic use*; D002417:Cattle; D002710:Chlorhexidine / Q000627:therapeutic use*; D002939:Ciprofloxacin / Q000008:administration & dosage; D003773:Dental Plaque / Q000382:microbiology; D003804:Dentin / Q000382:microbiology*; D006801:Humans; D008795:Metronidazole / Q000008:administration & dosage; D050296:Microbial Viability / Q000187:drug effects; D018613:Microscopy, Confocal; D008911:Minocycline / Q000008:administration & dosage; D018704:Orthodontic Retainers; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D000891:Anti-Infective Agents, Local; D008795:Metronidazole; D002939:Ciprofloxacin; D008911:Minocycline; D002126:Calcium Hydroxide; D002710:Chlorhexidine