title: Antibacterial and anti-biofilm activity of mouthrinses containing cetylpyridinium chloride and sodium fluoride.
abstract: BACKGROUND
  Cetylpyridinium chloride (CPC) and sodium fluoride augment oral hygiene by inactivating bacteria and inhibiting enamel demineralisation, respectively. However, there are few reports in the literature documenting the antibacterial efficacy of their combined use in mouthrinses. We have used six experimental systems to compare the antibacterial effects of mouthrinses containing 0.075% CPC (test rinse, TR) or 0.075% CPC with sodium fluoride (test fluoride rinse, TFR).
  
  
  RESULTS
  Effects against planktonic bacteria were determined using viable counting (for Streptococcus mutans and salivary bacteria), a redox dye (for Actinomyces viscosus and salivary bacteria) and viable counting (for ex vivo oral rinses). Effects against saliva-derived biofilms were quantified using confocal microscopy and differential viable counting. Inhibition of biofilm formation was evaluated by pre-treating hydroxyapatite coupons with mouthrinses prior to inoculation. Otherwise-identical controls without CPC (control rinse and control fluoride rinse, CR and CFR, respectively), were included throughout. Compared to the controls, TFR and TR demonstrated significant antimicrobial effects in the redox assays, by viable counts (>3 log reductions) and in oral rinse samples (>1.25 log reductions, p < 0.05). TFR and TR also significantly reduced the viability of oral biofilms. Pre-treatment of hydroxyapatite with TFR and TR significantly inhibited biofilm formation (>3 log difference, p < 0.05). Overall, there were no consistent differences in the activities of TR and TFR.
  
  
  CONCLUSIONS
  Sodium fluoride did not influence the antibacterial and anti-biofilm potency of CPC-containing formulations, supporting the combined use of CPC and sodium fluoride in mouthrinses to control oral bacteria and protect tooth enamel.
authors: Manchester Pharmacy School, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. joe.latimer@manchester.ac.uk.
authors: Joe
authors: J
authors: Latimer
authors: Manchester Pharmacy School, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. jodie.munday@manchester.ac.uk.
authors: Jodie L
authors: JL
authors: Munday
authors: Manchester Pharmacy School, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. kara.buzza@manchester.ac.uk.
authors: Kara M
authors: KM
authors: Buzza
authors: Manchester Pharmacy School, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. sarah.forbes@manchester.ac.uk.
authors: Sarah
authors: S
authors: Forbes
authors: Colgate-Palmolive Technology Center, Piscataway, NJ, USA. prem_sreenivasan@colpal.com.
authors: Prem K
authors: PK
authors: Sreenivasan
authors: Manchester Pharmacy School, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. andrew.mcbain@manchester.ac.uk.
authors: Andrew J
authors: AJ
authors: McBain
mesh_terms: D000328:Adult; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D002594:Cetylpyridinium / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D050296:Microbial Viability / Q000187:drug effects*; D009067:Mouthwashes / Q000494:pharmacology*; D012969:Sodium Fluoride / Q000494:pharmacology*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000891:Anti-Infective Agents, Local; D009067:Mouthwashes; D012969:Sodium Fluoride; D002594:Cetylpyridinium