title: Community-level assessment of dental plaque bacteria susceptibility to triclosan over 19 years.
abstract: BACKGROUND
  Triclosan is a broad-spectrum antimicrobial agent used in toothpaste to reduce dental plaque, gingivitis and oral malodor. This community-level assessment evaluated the susceptibility of dental plaque bacteria to triclosan in samples collected over 19 years.
  
  
  METHODS
  A total of 155 dental plaque samples were collected at eleven different times over 19 years from 58 adults using 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride toothpaste and from 97 adults using toothpaste without triclosan. These included samples from 21 subjects who used triclosan toothpaste for at least five years and samples from 20 control subjects. The samples were cultured on media containing 0, 7.5 or 25 μg/ml triclosan. Descriptive statistics and p values were computed and a linear regression model and the runs test were used to examine susceptibility over time.
  
  
  RESULTS
  Growth inhibition averaged 99.451% (91.209 - 99.830%) on media containing 7.5 μg/ml triclosan and 99.989% (99.670 - 100%) on media containing 25 μg/ml triclosan. There was no change in microbial susceptibility to triclosan over time discernible by regression analysis or the runs test in plaque samples taken over 19 years including samples from subjects using a triclosan-containing dentifrice for at least five years.
  
  
  CONCLUSIONS
  This community-level assessment of microbial susceptibility to triclosan among supragingival plaque bacteria is consistent with the long-term safety of a 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride dentifrice.
authors.forename: Violet I
authors.initials: VI
authors.lastname: Haraszthy
authors.forename: Prem K
authors.initials: PK
authors.lastname: Sreenivasan
authors.affiliation: University at Buffalo, School of Dental Medicine, 222 Foster Hall, 3435 Main Street, Buffalo NY 14214-3008, USA. jjzambon@buffalo.edu.
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Zambon
mesh_terms: D000328:Adult; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D001419:Bacteria / Q000187:drug effects*; D058491:Bacterial Load; D001431:Bacteriological Techniques; D002327:Cariostatic Agents / Q000627:therapeutic use; D003773:Dental Plaque / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability; D012969:Sodium Fluoride / Q000627:therapeutic use; D014100:Toothpastes / Q000627:therapeutic use; D014260:Triclosan / Q000627:therapeutic use*
chemical_list: D000891:Anti-Infective Agents, Local; D002327:Cariostatic Agents; D014100:Toothpastes; D014260:Triclosan; D012969:Sodium Fluoride