title: Antimicrobial efficacy of 0·05% cetylpyridinium chloride mouthrinses.
abstract: This study evaluated the antimicrobial activity of two commercially available 0·05% cetylpyridinium chloride (CPC) mouthrinses with or without alcohol and examined its antimicrobial activity on oral bacterial species including fresh clinical isolates compared to a chlorhexidine mouthrinse and a control fluoride mouthrinse without CPC. Two different approaches were used to evaluate antimicrobial activity. First, the minimum inhibitory concentration (MIC) was determined for each mouthrinse against a panel of 25 micro-organisms including species associated with dental caries, gingivitis and periodontitis. Second, supragingival dental plaque obtained from 15 adults was incubated with the four mouthrinses to evaluate antimicrobial activity on micro-organisms in oral biofilms. Both CPC mouthrinses exhibited lower MIC's, that is, greater antimicrobial activity, against oral Gram-negative bacteria especially periodontal pathogens and species implicated in halitosis such as Aggregatibacter actinomycemcomitans, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei than the control mouthrinse. Ex-vivo tests on supragingival plaque micro-organisms demonstrated significantly greater antimicrobial activity by the CPC mouthrinses (>90% killing, P < 0·001) and the chlorhexidine rinse (>98% killing, P < 0·05) compared to the control fluoride mouthrinse. Whilst the chlorhexidine mouthrinse was most effective, mouthrinses containing 0·05% CPC formulated with or without alcohol demonstrated broad-spectrum antimicrobial activity against both laboratory strains and supragingival plaque bacteria compared to a control mouthrinse without CPC.
  
  
  CONCLUSIONS
  These in vitro and ex-vivo studies provide a biological rationale for previous clinical studies demonstrating the efficacy of CPC mouthrinses in reducing supragingival plaque and plaque-associated gingivitis.
authors.affiliation: Colgate Palmolive Company, Piscataway, NJ, USA.
authors.forename: P K
authors.initials: PK
authors.lastname: Sreenivasan
authors.forename: V I
authors.initials: VI
authors.lastname: Haraszthy
authors.forename: J J
authors.initials: JJ
authors.lastname: Zambon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000145:classification / Q000187:drug effects*; D018441:Biofilms / Q000187:drug effects; D002594:Cetylpyridinium / Q000494:pharmacology*; D002710:Chlorhexidine / Q000494:pharmacology; D003773:Dental Plaque / Q000382:microbiology; D000431:Ethanol / Q000494:pharmacology; D005459:Fluorides / Q000494:pharmacology; D006801:Humans; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009067:Mouthwashes / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D009067:Mouthwashes; D000431:Ethanol; D002594:Cetylpyridinium; D005459:Fluorides; D002710:Chlorhexidine