A preliminary comparison of the effect of 0.3% versus 0.2% chlorhexidine mouth rinse on de novo plaque formation: a monocentre randomized double‐blind crossover trial

Objective Chlorhexidine ( CHX ) is considered the gold standard against gram‐negative microorganisms. Little has been written about the simultaneous influence that both time and concentration could have on antiplaque formation effectiveness of CHX . The aim of this study is to compare the clinical and microbiological effectiveness of two different CHX concentrations and time applications in a 4‐day plaque regrowth study model. Material and methods Twenty volunteers were enrolled in a randomized double‐blind crossover study comparing the effectiveness of CHX 0.3% and CHX 0.2% mouth rinses applied for 15 and 30 s, respectively. Plaque index ( PII ), total bacterial counts and the detection of specific periopathogens were measured at the 5th day of each mouth rinse application. Taste acceptance was evaluated using a questionnaire. Results Chlorhexidine 0.3% resulted in a statistically greater reductions (10%) in PI l and periopathogens compared to CHX 0.2%. Furthermore, patients reported comparable taste acceptance in both groups. Conclusion Chlorhexidine is an effective oral antiseptic. The CHX 0.3% mouth rinse formulation used for 15 s resulted in superior clinical and microbiological outcomes compared to the CHX 0.2% formulation, used for 30 s.