The effects of three different mouth rinses in a 4-day supragingival plaque regrowth study

OBJECTIVE: This study compares the effects of three different mouth rinses with respect to reducing Streptococcus mutans (S. mutans) colony counts on the teeth and tongue surfaces. MATERIALS AND METHODS: In this study, comparison tests using the alcohol-free 0.1% chlorhexidine mouth rinse, alcohol-containing essential oil mouth rinse, and alcohol-free essential oil-containing mouth rinse were conducted. Patients were instructed to avoid mechanical cleaning with either a toothbrush or toothpick for 4 days. The first samples were collected from teeth surfaces and the dorsum of the tongue after a professional cleaning, and the second samples were collected after a 4-day plaque re-growth period. The supragingival plaque from the buccal surfaces of teeth #11, 14, 31, 34 as well as samples from the dorsum of the tongue, were assessed using the Dentocult(®) strips. RESULTS: The Listerine(®) and Ondrohexidine(®) groups did not show any statistically significant differences between the values of the two samples (P = 0.734, P = 0.307). The MC(®) group and the control group showed significantly higher results than the first sample values. The effectiveness of the mouth rinses on S. mutans colony counts from the teeth surfaces were higher in the Listerine(®), Ondrohexidine(®), and Mouthwash Concentrate(®) groups. The difference between the first and second samples of the S. mutans colony counts from the tongue surface was found to be statistically significant, and S. mutans colony counts were higher than the first sample (P = 0.015). CONCLUSION: Alcohol and essential oil-containing Listerine(®) mouth rinse, alcohol-free Ondrohexidine(®), alcohol-free essential oil-containing MC(®) mouth rinse had the same effect on S. mutans counts, higher than the 1% alcohol solution on teeth surface. They had the ability to maintain the S. mutans counts at the same level for 4 days in patients who did not perform any mechanical oral hygiene regimen.