RESUMO
The effectiveness of an antimicrobial mouthwash (alexidine, 2-ethylhexyl bisbiguanidine dihydrochloride) in preventing plaque and gingivitis was evaluated in 45 young male adults. In a study using a double-blind cross-over design, subjects received a thorough prophylaxis and refrained from all routine oral hygiene for 2 weeks. During this period, subjects rinsed twice daily with either a treatment (alexidine) or placebo mouthwash. Plaque and gingivitis were assessed on selected teeth on days 2, 7 and 14. The characteristics of plaque that were recorded include: surface area score, dry weight and differential counts of microorganisms. After the 14th day, subjects resumed their regular oral hygiene practices for 3 weeks before starting the second experimental period. Aftter a second prophylaxis, the treatment and placebo groups from the first 2 weeks were crossed over and the procedures followed previously were repeated during the sixth and seventh weeks. The alexidine mouthwash was statistically and clinically effective in decreasing plaque scores and plaque weight, and statistically but not clinically effective in decreasing gingivitis scores. No systemic side effects were observed, but an asymptomatic brown tongue stain was observed in about half of the subjects. There was no evidence to suggest that alexidine disturbed the relative composition of the microorganisms in plague, but there was a suggestion that it decreased the number of microorganisms almost 2-fold when compared with the placebo group.
