title: Plaque-left-behind after brushing: intra-oral reservoir for antibacterial toothpaste ingredients.
abstract: OBJECTIVE
  Plaque is never fully removed by brushing and may act as a reservoir for antibacterial ingredients, contributing to their substantive action. This study investigates the contribution of plaque-left-behind and saliva towards substantivity of three antibacterial toothpastes versus a control paste without antibacterial claims.
  
  
  METHODS
  First, volunteers brushed 2 weeks with a control or antibacterial toothpaste. Next, plaque and saliva samples were collected 6 and 12 h after brushing and bacterial concentrations and viabilities were measured. The contributions of plaque and saliva towards substantivity were determined by combining control plaques with experimental plaque or saliva samples and subsequently assessing their viabilities. Bacterial compositions in the various plaque and saliva samples were compared using denaturing gradient gel electrophoresis.
  
  
  RESULTS
  The viabilities of plaques after brushing with Colgate-Total® and Crest-Pro-Health® were smaller than of control plaques and up to 12 h after brushing with Crest-Pro-Health® plaques still contained effective, residual antibacterial activity against control plaques. No effective, residual antibacterial activity could be measured in saliva samples after brushing. There was no significant difference in bacterial composition of plaque or saliva after brushing with the different toothpastes.
  
  
  CONCLUSIONS
  Plaque-left-behind after mechanical cleaning contributes to the substantive action of an antibacterial toothpaste containing stannous fluoride (Crest-Pro-Health®).
  
  
  CONCLUSIONS
  The absorptive capacity of plaque-left-behind after brushing is of utmost clinical importance, since plaque is predominantly left behind in places where its removal and effective killing matter most. Therewith this study demonstrates a clear and new beneficial effect of the use of antibacterial toothpastes.
authors.affiliation: Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
authors.forename: Marieke P T
authors.initials: MP
authors.lastname: Otten
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Busscher
authors.forename: Frank
authors.initials: F
authors.lastname: Abbas
authors.forename: Henny C
authors.initials: HC
authors.lastname: van der Mei
authors.forename: Chris G
authors.initials: CG
authors.lastname: van Hoogmoed
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D058645:Denaturing Gradient Gel Electrophoresis; D003773:Dental Plaque / Q000382:microbiology* / Q000517:prevention & control*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D012463:Saliva / Q000382:microbiology*; D014100:Toothpastes / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D014100:Toothpastes