title: A new Plaque Glycolysis and Regrowth Method (PGRM) for the in vivo determination of antimicrobial dentifrice/rinse efficacy towards the inhibition of plaque growth and metabolism--method development, validation and initial activity screens.
abstract: A new method, the Plaque Glycolysis and Regrowth Method (PGRM), is described for the evaluation of antimicrobial effects on plaque metabolism in vivo. The method relies on the experimental observation that in vivo sampled dental plaques, collected from different quadrants of the dentition, produce equivalent rates of metabolic activity and regrowth when similarly dispersed and normalized into incubation media. In applications of the technique to antimicrobial evaluations, overnight fasted dental plaque is collected from a non-treated quadrant of the dentition along the gingival margin. Topical formulations are used in vivo. Following this, dental plaques are collected from other dentition quadrants at extended times, allowing for the back diffusion, clearance and natural intraoral deactivation of antimicrobials within the oral cavity. In vivo treated and non-treated plaque samples are subsequently tested for metabolic and regrowth activity under controlled and standardized conditions in vitro following normalization for biomass. The technique thus combines the necessary biological factors important to the legitimate evaluation of antimicrobial effects in vivo, while benefiting from the improved precision and control provided by in vitro assessment of plaque activity. In this paper evidence is presented validating the PGRM method, and initial activity screens of commercial antimicrobial mouthrinses and toothpastes, including a new stabilized stannous fluoride dentifrice, are described.
authors.affiliation: The Procter and Gamble Company, Sharon Woods Technical Center, Cincinnati, Ohio, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: White
authors.forename: E R
authors.initials: ER
authors.lastname: Cox
authors.forename: N
authors.initials: N
authors.lastname: Liang
authors.forename: D
authors.initials: D
authors.lastname: Macksood
authors.forename: L
authors.initials: L
authors.lastname: Bacca
mesh_terms: D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local / Q000494:pharmacology / Q000627:therapeutic use; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development; D002594:Cetylpyridinium / Q000494:pharmacology / Q000627:therapeutic use; D002710:Chlorhexidine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D018592:Cross-Over Studies; D003773:Dental Plaque / Q000378:metabolism / Q000382:microbiology* / Q000517:prevention & control*; D003802:Dentifrices / Q000494:pharmacology / Q000627:therapeutic use*; D004338:Drug Combinations; D005460:Fluorides, Topical / Q000494:pharmacology / Q000627:therapeutic use; D006019:Glycolysis / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009067:Mouthwashes / Q000494:pharmacology* / Q000627:therapeutic use; D010865:Pilot Projects; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology / Q000627:therapeutic use; D015203:Reproducibility of Results; D012459:Salicylates / Q000494:pharmacology / Q000627:therapeutic use; D012969:Sodium Fluoride / Q000494:pharmacology / Q000627:therapeutic use; D013729:Terpenes / Q000494:pharmacology / Q000627:therapeutic use; D014002:Tin Fluorides / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000891:Anti-Infective Agents, Local; C098421:Crest Gum Care; D003802:Dentifrices; D004338:Drug Combinations; D005460:Fluorides, Topical; D009067:Mouthwashes; D000644:Quaternary Ammonium Compounds; D012459:Salicylates; C094642:Scope mouthwash; D013729:Terpenes; D014002:Tin Fluorides; C057473:Listerine; D012969:Sodium Fluoride; D002594:Cetylpyridinium; C010882:chlorhexidine gluconate; D002710:Chlorhexidine