The substantivity of a number of oral hygiene products determined by the duration of effects on salivary bacteria
The aim of this study was to compare the antimicrobial substantivity of a number of oral hygiene products and experimental formulations by recording effects on salivary bacteria. It was thought that the study would provide information which would be relevant to, even predictive of, the clinical activity of the formulations under test.
Twenty volunteers took part in the blind, 10-cell, randomized, single rinse, crossover salivary bacterial count study, which was balanced for carryover. Two rinses containing chlorhexidine or C31G, four rinses containing cetylpyridinium chloride (CPC) with and without fluoride and/or alcohol, a minus-CPC control rinse, and two toothpastes with and without stannous fluoride were used. Water was also used as a control. On the day of each study, volunteers suspended oral hygiene habits and rinsed with the specified formulation. Unstimulated saliva samples were collected immediately before and 30, 60,180, 300, and 420 minutes after rinsing. The samples were immediately processed for total anaerobic bacterial counts.
All rinses except the two controls (water and minus-CPC) showed significant falls in counts to 30 minutes. C31G showed substantivity compared to water only for 60 minutes. Chlorhexidine showed greater substantivity compared to C31G from 30 to 420 minutes. The CPC rinses were significantly more substantive than their controls between 130 and 300 minutes. The stannous fluoride and control pastes were similarly substantive to 300 minutes.
Overall the 10 formulations, based on antimicrobial action, varied considerably in substantivity owing to their comparative plaque inhibitory properties. [D.S.S.]
Elworthy, A., J. Greenman, F. Doherty, R. Newcombe, and M. Addy, J Periodont, 67:572, 1996