title: Comparative effects of quaternary ammonium mouthrinses on 4-day plaque regrowth.
abstract: BACKGROUND
  Quaternary ammonium compounds constitute a large group of antibacterial chemicals with a potential for inhibiting plaque and gingivitis. One compound, benzalkonium chloride (BC), may be of value, although there is a dearth of evidence to support efficacy. The aim of this study was to measure the ability of 2 BC mouthrinses (0.05% and 0.1%) to inhibit de novo plaque reformation.
  
  
  METHODS
  A 4-day plaque regrowth model. For comparative purposes, a commercial mouthrinse containing cetyl pyridinium chloride (CPC) and a positive control chlorhexidine (CX) mouthrinse were also evaluated.
  
  
  RESULTS
  Compared to water control, a reduction in plaque scores of 52% was noted for the CX mouthrinse, 22.5% for CPC and 5% and 6% for the 2 BC rinses. For plaque area, reductions of 84%, 47%, 16% and 15% were found for CX, CPC, and the 2 BC rinses, respectively. Significant reductions in plaque area compared to the water rinse were also seen with the 2 BC rinses (p<0.05). However, for both plaque score and plaque area, the CX and CPC rinses significantly reduced plaque compared to the BC rinses (p<0.0001).
  
  
  CONCLUSIONS
  These findings would suggest that the 2 benzalkonium rinses would only have a limited value at inhibiting plaque formation.
authors.affiliation: Department of Oral & Dental Science, University of Bristol, UK.
authors.forename: J
authors.initials: J
authors.lastname: Moran
authors.forename: M
authors.initials: M
authors.lastname: Addy
authors.forename: R
authors.initials: R
authors.lastname: Jackson
authors.forename: R G
authors.initials: RG
authors.lastname: Newcombe
mesh_terms: D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D001548:Benzalkonium Compounds / Q000627:therapeutic use*; D002594:Cetylpyridinium / Q000627:therapeutic use; D002710:Chlorhexidine / Q000627:therapeutic use; D003773:Dental Plaque / Q000517:prevention & control*; D003774:Dental Plaque Index; D006801:Humans; D009067:Mouthwashes / Q000627:therapeutic use*; D016037:Single-Blind Method; D017211:Treatment Failure
chemical_list: D000891:Anti-Infective Agents, Local; D001548:Benzalkonium Compounds; D009067:Mouthwashes; D002594:Cetylpyridinium; D002710:Chlorhexidine