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VOLUME 22 , ISSUE 8 ( August, 2021 ) > List of Articles


Efficacy of Licorice on Salivary Streptococcus mutans Levels vs Chlorhexidine Mouthwash in High Caries Risk Patients: A Randomized Clinical Trial

Nancy Helmy, Shereen Hafez, Amira Farid

Keywords : Chlorhexidine mouthwash, Herbal licorice mouthwash, High caries index, Randomized clinical trial, Salivary Streptococcus mutans level

Citation Information : Helmy N, Hafez S, Farid A. Efficacy of Licorice on Salivary Streptococcus mutans Levels vs Chlorhexidine Mouthwash in High Caries Risk Patients: A Randomized Clinical Trial. J Contemp Dent Pract 2021; 22 (8):914-921.

DOI: 10.5005/jp-journals-10024-3156

License: CC BY-NC 4.0

Published Online: 09-11-2021

Copyright Statement:  Copyright © 2021; The Author(s).


Aim: To evaluate the efficacy of an innovative herbal licorice mouthwash on reducing salivary Streptococcus mutans levels versus chlorhexidine mouthwash in high caries risk patients. Methodology: A total number of 52 high caries risk patients were assigned to this study. Patients were randomly divided into two groups (n = 26) according to the type of mouthwash (G): Patients in group G1 used the mouthwash containing chlorhexidine, while patients in group G2 used the mouthwash containing the innovative licorice extract. Afterward, each group was further divided into three subgroups according to the time (T): T0 represents the baseline, T1 represents the time immediately after using the mouthwash, and T2 represents the time 1 week after using the mouthwash. Furthermore, pH and plaque index were recorded. Data were statistically analyzed using a Chi-square test for categorical data, Shapiro-Wilk test for numerical data, and one-way repeated measures ANOVA followed by Bonferroni post hoc test for intragroup comparisons. The significance level was set at p ≤0.05 for all tests. Statistical analysis was performed with IBM® SPSS® Statistics version 26 for Windows. Results: It was found that in high caries risk patients, there was no significant difference between licorice and chlorhexidine mouthwashes regarding Streptococcus bacterial count. Moreover, it was found that licorice mouthwash stimulates salivary flow, and thus, it raises salivary pH in patients with high caries risk. However, the plaque index of chlorhexidine showed better results. Additionally, there was a positive weak correlation between bacterial count and plaque index. Conclusions: Licorice mouthwash may demonstrate a promising antibacterial effect that can be a suitable alternative for current synthetic mouthwashes. Clinical significance: Natural herbal mouthwash could be incorporated in dental preventive measures and could be used as cavity-fighting compound. It introduces a minimal health hazard substitute for conventional synthetic preventive measures.

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