title: In vitro Resistance Testing of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to Triclosan.
abstract: OBJECTIVE
  To determine the sensitivity of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to triclosan, and determine if these bacteria develop resistance to triclosan upon prolonged exposure.
  
  
  METHODS
  Susceptibility to triclosan was tested against three periodontal pathogens P. gingivalis, P. intermedia, and T. forsythia. Escherichia coli strains sensitive and resistant to triclosan were used as biological controls to confirm the efficacy of triclosan in the assays. Agar plates were prepared locally with vitamin K and hemin-supplemented medium.
  
  
  RESULTS
  Porphyromonas gingivalis and P. intermedia did not grow on plates containing ≥ 2 μg/ml triclosan, while T. forsythia did not grow on ≥ 1.66 μg/ml. Colonies of P. intermedia resistant to triclosan developed after prolonged incubation at 2 μg/ml, but this resistance disappeared during subculture in the absence of triclosan.
  
  
  CONCLUSIONS
  No significant resistance to triclosan was detected for these species.
  
  
  CONCLUSIONS
  Dental products containing triclosan can be beneficial in controlling periodontal disease.
authors.affiliation: Assistant Professor, Department of Pediatric Dentistry, King Abdulaziz University Jeddah, Kingdom of Saudi Arabia, e-mail: Deema.farsi@gmail.com.
authors.forename: Deema
authors.initials: D
authors.lastname: Farsi
authors.affiliation: Department of Microbiology, The Forsyth Institute, Cambridge Massachusetts, USA.
authors.forename: Anne
authors.initials: A
authors.lastname: Tanner
mesh_terms: D024881:Drug Resistance, Bacterial; D016966:Porphyromonas gingivalis / Q000187:drug effects*; D018713:Prevotella intermedia / Q000187:drug effects*; D000070436:Tannerella forsythia / Q000187:drug effects*; D014260:Triclosan / Q000494:pharmacology*
chemical_list: D014260:Triclosan
keywords: Laboratory research; Porphyromonas gingivalis; Prevotella intermedia; Tannerella forsythia; Triclosan susceptibility.