Effectiveness of chitosan mouthwash on plaque formation and levels of salivary Streptococcus and Lactobacillus count: an in vivo study

Aparna Indu S. R., Sharan S. Sargod, Sham S. Bhat, Shamjith Manikkoth, N. Ramakrishnan


Background: The objectives of the present study were to clinically evaluate the effectiveness of chitosan mouthwash on Plaque formation and to evaluate the antimicrobial activity against salivary Streptococcus mutans (SM) and Lactobacillus (LB).

Methods: A total of 20 participants with decay-missing-filled index ≥4 and simplified oral hygiene index score >1.3 were recruited for the study after taking informed consent. All the participants were provided a bottle of chitosan mouthwash in addition to their usual oral hygiene procedure. Baseline salivary SM and LB levels were determined, using chair-side CRT® bacteria test prior giving chitosan mouthwash and after 14 days, during which children are advised to use 10 ml of mouthwash for 60 seconds two times daily. Plaque index score recorded using Silness and Loe plaque index. Paired t-test (or corresponding non-parametric) and percentage comparison method using cross tables were used for statistical analysis.

Results: The baseline plaque index score of 0.758 and after 14 days of mouthwash use, it reduced to 0.434. The mean difference in the plaque index showed significant reduction in the plaque score (i.e., with the difference of 0.324). The results showed the antiplaque effects with a short duration of 14 days use of chitosan (CH) mouthwash. The antibacterial activity demonstrated a range of inhibitory effect on salivary SM and LB.

Conclusions: CH showed an evident strong effect against salivary SM and LB levels and controlling the plaque biofilm formation. So water soluble CH can be used in new formulations for oral applications not only as antimicrobial agent but also for plaque biofilm control.


Chitosan, SM, LB, Mouthwash, Plaque, In vivo

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