Alcohol-free mouthrinse solutions to reduce supragingival plaque regrowth and vitality - A controlled clinical study

Background: The aim of this study was to evaluate the clinical and antibacterial properties of alcohol-free mouthrinses, an amine fluoride/stannous fluoride mouthrinse (ASF) and two triclosan solutions in comparison with a chlorhexidine and a placebo rinse. Material and methods: In a double-blind, randomised 5-cell cross-over 4-day plaque regrowth study, 19 volunteers rinsed 2 x a day with 15 mi of each of the distributed solutions. Each test cycle was followed by a 10 days wash-out period. On day 0 of each test week, volunteers received a dental prophylaxis. Thereafter they refrained from all mechanical oral hygiene procedures for the next four days. Plaque regrowth was assessed daily by the plaque index and on day 4 by calculating the plaque area with a computer program after disclosure and photography of the front teeth. The vitality of the plaque was examined on days 1 to 4 by the vital fluorescence technique. Results: 19 participants completed the study. Compared to the placebo the ASF solution showed 15.7% (p>0.5), 30.6% (p<0.001), 40.5% (p<0.001) and 44.7% (p<0.001) reductions on the consecutive days 1-4 in plaque index and a reduction of 61.9% in plaque area. The decrease of vitality of supragingival plaque was highly significant compared to placebo on every test day ranging between 30.9% and 36.6%. A reduction in plaque index from 19.4% (p<0.01) on day 2, 34.9% (p<0.001) on day 3 and 40.4% (p<0.001) on day 4 concommitant with a reduction in plaque area of 48.9% (p<0.001) was noted for alcohol-free chlorhexidine. Concerning the vitality chlorhexidine reduced the percentage of vital bacteria significantly on every day (16.0% to 24.9%). The reductions in mean plaque index for the 0.15% triclosan solution during the test period were 6.3%, 22.4%, 24.6% and 36% and in plaque area 41.8%. Vitality was significantly reduced at every day compared to placebo. Plaque Index reduction with the 0.02% triclosan increased from 15.3% (day 2) to 31.0% (day 4) and a reduction of 23.6% was seen in plaque area. A significant effect concerning the vitality of the plaque was only found at the first and the last day of the test cycle. Conclusion: Alcohol-free mouthrinse solutions were shown to be effective in reducing both plaque accumulation and plaque biofilm vitality compared to a placebo solution.