The use of plaque area and plaque index to measure the effect of fluoride and chlorhexidine toothpastes on 24-h plaque regrowth.
Short-term methodologies have been developed to screen chemical agents for plaque inhibitory effects. Most measure inhibition of plaque regrowth over several days. A method was described to study agents over 16-24 h periods, although some difficulties with the index used were reported. The aim of this study was to determine whether more conventional plaque scoring methods could be used. These 2 crossover studies measured plaque regrowth over 24 h in 20 subjects and in response to single brushings with either a chlorhexidine and minus active toothpaste or to a fluoride toothpaste product and water. Significantly less plaque had reformed after brushing with the chlorhexidine toothpaste compared with its control and with the fluoride toothpaste compared with water. 18 subjects participated in both studies and using their data for an interstudy comparison, less plaque developed with the chlorhexidine compared with the fluoride toothpaste. These studies had the advantage that longer-term trials already demonstrated the same differences. This permits one to conclude with some certainty that the 24-h plaque regrowth study design, using conventional measures of plaque accumulation, could be a useful and rapid method of screening potential plaque inhibitory agents and formulations.
Claydon
N
N
Dentistry, Department of Oral and Dental Disease, University of Bristol, England.
Addy
M
M
D000891:Anti-Infective Agents, Local / Q000008:administration & dosage / Q000627:therapeutic use*; D002710:Chlorhexidine / Q000008:administration & dosage / Q000627:therapeutic use*; D018592:Cross-Over Studies; D003773:Dental Plaque / Q000473:pathology* / Q000517:prevention & control*; D003774:Dental Plaque Index; D005459:Fluorides / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D010919:Placebos; D014099:Toothbrushing; D014100:Toothpastes; D014867:Water
D000891:Anti-Infective Agents, Local; D010919:Placebos; D014100:Toothpastes; D014867:Water; D005459:Fluorides; D002710:Chlorhexidine