Effect of an intensified treatment with 40% chlorhexidine varnish on plaque acidogenicity

Previous work showed that a single application of 40% chlorhexidine varnish, EC40®, reduced plaque acidogenicity upon sucrose challenge during less than 3 weeks. It was questioned whether lactic acid production could be reduced significantly longer when the treatment was intensified. Therefore, the effects of three consecutive EC40® applications on plaque acidogenicity were evaluated. Nine subjects who participated in the previous study received three full mouth EC40® applications within 1 week. Before the first application and up to 9 weeks after the third application, plaque samples were taken after a 10% sucrose rinse and analyzed for organic acids with capillary electrophoresis. At baseline, the mean provoked lactic acid concentration was 1.64 (±0.69) μmol/mg protein. At the first and seventh day after the third application, there was too little plaque to measure acid concentrations. At 2 weeks after the third application, lactic acid concentrations were significantly reduced (p 0.05). We conclude that a triple 40% chlorhexidine varnish treatment did not affect plaque acidogenicity for more than 3 weeks. From comparison with a previous study, we conclude that the triple treatment with EC40® within 1 week was not more effective in reducing plaque acidogenicity than the single one.