title: Effect of mouthwashes on the composition and metabolic activity of oral biofilms grown in vitro.
abstract: OBJECTIVE
  The aim of this study was to determine the effect of an oxygenating mouthwash compared to two other established mouthwash products on bacterial composition and metabolic activity of oral biofilms in vitro.
  
  
  METHODS
  Twelve healthy subjects participated as donors. Plaque-saliva mixture inoculated biofilms were grown and treated with 3 different chemotherapeutic mouthwashes [amine fluoride/stannous fluoride (MD), oxygenating agent (AX), chlorhexidine 0.12 % (PA), and water (W)]. Effects of treatments were assessed on biofilm composition (16S rRNA gene amplicon sequencing), production of organic acids (formate, acetate, lactate, propionate, butyrate using capillary electrophoresis), and viability of the remaining biofilm (CFUs).
  
  
  RESULTS
  Microbial profiles of biofilms clustered per inoculum donor and were dominated by the genera Veillonella, Streptococcus, and Prevotella. Microbial diversity was only reduced after PA treatment. Significant changes in composition occurred after treatment with AX, resulting in lower proportions of Veillonella and higher proportions of non-mutans streptococci. Production of all organic acids after PA and lactate after MD was significantly lower as compared to W. AX resulted in reduction of acetate, butyrate, and propionate and increase in lactate production (p < 0.05). Viable counts were significantly lower after PA and AX treatments compared to W, while no significant reduction was observed after MD.
  
  
  CONCLUSIONS
  All studied mouthwashes affected the in vitro biofilms differently. The effects of the AX treatment were the most prominent which resulted in changes of the bacterial composition and metabolism.
  
  
  CONCLUSIONS
  Awareness by the dental team that mouthwashes can change the bacterial composition and metabolism is important when advising its use.
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Free University Amsterdam, Gustav Mahlerlaan 3004, 1081, LA, Amsterdam, The Netherlands. M.Fernandez.y.Mostajo@acta.nl.
authors.forename: Mercedes
authors.identifier: http://orcid.org/0000-0002-5341-3015
authors.initials: M
authors.lastname: Fernandez Y Mostajo
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Free University Amsterdam, Gustav Mahlerlaan 3004, 1081, LA, Amsterdam, The Netherlands.
authors.forename: Rob A M
authors.initials: RAM
authors.lastname: Exterkate
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Free University Amsterdam, Gustav Mahlerlaan 3004, 1081, LA, Amsterdam, The Netherlands.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Buijs
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Free University Amsterdam, Gustav Mahlerlaan 3004, 1081, LA, Amsterdam, The Netherlands.
authors.forename: Wim
authors.initials: W
authors.lastname: Crielaard
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Free University Amsterdam, Gustav Mahlerlaan 3004, 1081, LA, Amsterdam, The Netherlands.
authors.forename: Egija
authors.initials: E
authors.lastname: Zaura
mesh_terms: D000328:Adult; D000588:Amines / Q000494:pharmacology; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects*; D002710:Chlorhexidine / Q000494:pharmacology; D004338:Drug Combinations; D005260:Female; D005460:Fluorides, Topical / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D054892:Metagenome; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009067:Mouthwashes / Q000494:pharmacology*; D016877:Oxidants / Q000494:pharmacology; D014002:Tin Fluorides / Q000494:pharmacology
chemical_list: D000588:Amines; D000891:Anti-Infective Agents, Local; D004338:Drug Combinations; D005460:Fluorides, Topical; D009067:Mouthwashes; D016877:Oxidants; D014002:Tin Fluorides; C094808:amine fluoride solution; C059813:Meridol; D002710:Chlorhexidine
keywords: Antimicrobials; Biofilm; Microcosm; Mouthwashes; Organic acids