Glycyrrhiza uralensis Protects Against Dental Caries by Reducing Bacterial Levels

by | Apr 4, 2022 | 2021, Botanicals, Oral Health

Written by Taylor Woosley, Staff Writer. Subjects using a Glycyrrhiza uralensis extract gargle for five days reported a substantial decrease in oral bacterial levels and positive temporal changes compared to subjects using a saline gargle.

dentist - oral healthOral health plays an essential role in the overall health of an individual. Past studies have highlighted an association between dental diseases and a variety of other chronic diseases, such as cardiovascular diseases, diabetes, and lung diseases 1. The 2016 Global Burden of Disease Study estimated that oral diseases affect around 3.5 billion people worldwide 2. Dental caries is one of the most prevalent non-communicable diseases that is considered a major public health problem globally 3. Dental caries is a biofilm mediated and multifactorial dynamic disease, which can cause severe pain, abscess, swelling, and fever, resulting in net mineral loss of dental hard tissues 4.

Good oral hygiene, along with following a healthy diet with minimal sugar, can help prevent this oral disease. For those already experiencing dental caries, supplementation and a proper dental routine may help reduce bacteria and decrease the odds of developing dental caries. Glycyrrhiza uralensis, a perennial herb belonging to family Leguminosae, has been studied for its potential ability to mitigate oral bacteria 5. Studies on the biological activity of Glycyrrhiza uralensis, also known as Chinese licorice, has proven its efficacy in providing antiviral, anti-inflammatory, and antibacterial properties 6. In particular, the compound glycyrrhizol A, present in the extract of the herb, contains robust levels of flavonoids that inhibit the activity of oral pathogens 7.

Kim Yu-Rin et al. conducted a trial to better explore the possible association between Glycyrrhiza uralensis and the occurrence of dental caries through a randomized, double-blind, placebo-controlled study. 60 subjects were assigned to one of two groups, the Glycyrrhiza uralensis extract gargle group (n=30, mean age of 45.53 years) or the saline gargle group (n=30, mean age of 44.27). Participants gargled once daily before bed for 5 days. Clinical measurements, such as assessment of caries activity and bacteria detection, were performed and evaluated using the Cariview test and microbiological analysis by trained dental hygienists.

A week before the start of the study, all participating subjects visited a dental clinic to receive an oral examination and experienced oral scaling to establish an identical oral environment. During the trial, participants were given the same type of toothbrush and toothpaste and a dental visit was conducted in the morning prior to any oral hygiene procedure. Dental hygienists collected data in terms of gargle activity, such as baseline before gargle, post gargle, and at the end of the trial. Significant results of the study are as follows:

  • There were no significant differences between the Glycyrrhiza uralensis and saline gargle groups at the baseline of the study before gargle application and directly after the gargle application (p > 0.05).
  • After 5 days of gargle application, a significant difference was observed (p < 0.05).
  • When comparing differences in temporal changes, no significant differences were noted in the saline gargle group (p < 0.05). However, significant changes were noted in the Glycyrrhiza uralensis extract group immediately after gargle application compared to baseline (p < 0.05).
  • When comparing risk factors, high risk was increased after 5 days of the saline gargle group, while the Glycyrrhiza uralensis group experienced an increase in low risk potential after 5 days.

Results of the study confirm the use of Glycyrrhiza uralensis as an effective treatment to decrease occurrence of dental caries. Compared to the saline group, it was not only a better anti-bacterial agent, but it also was deemed safe for continuous daily use. A limitation of the study is the small sample size and the short length of the trial. Kim Yu-Rin et al. confirm that their future trials will further examine and compare this herb with other commercially available mouthwashes to better explore its efficacy.

Source: Kim, Yu-Rin, and Seoul-Hee Nam. “A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of a Mouthwash Containing Glycyrrhiza uralensis Extract for Preventing Dental Caries.” International Journal of Environmental Research and Public Health 19, no. 1 (2021): 242.

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

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Posted April 4, 2022.

Taylor Woosley studied biology at Purdue University before becoming a 2016 graduate of Columbia College Chicago with a major in Writing. She currently resides in Glen Ellyn, IL.

References:

  1. Fiorillo L. Oral Health: The First Step to Well-Being. Medicina (Kaunas). Oct 7 2019;55(10)doi:10.3390/medicina55100676
  2. Fraihat N, Madae’en S, Bencze Z, Herczeg A, Varga O. Clinical Effectiveness and Cost-Effectiveness of Oral-Health Promotion in Dental Caries Prevention among Children: Systematic Review and Meta-Analysis. Int J Environ Res Public Health. Jul 25 2019;16(15)doi:10.3390/ijerph16152668
  3. Ladewig NM, Camargo LB, Tedesco TK, et al. Management of dental caries among children: a look at the cost-effectiveness. Expert Rev Pharmacoecon Outcomes Res. Apr 2018;18(2):127-134. doi:10.1080/14737167.2018.1414602
  4. Machiulskiene V, Campus G, Carvalho JC, et al. Terminology of Dental Caries and Dental Caries Management: Consensus Report of a Workshop Organized by ORCA and Cariology Research Group of IADR. Caries Res. 2020;54(1):7-14. doi:10.1159/000503309
  5. Lu Q, Wu X, Han W, et al. Effect of Glycyrrhiza uralensis against ulcerative colitis through regulating the signaling pathway of FXR/P-gp. Am J Transl Res. 2021;13(8):9296-9305.
  6. Yang YY, Li SN, Xu L, et al. The complete mitochondrial genome of Glycyrrhiza uralensis Fisch. (Fabales, Leguminosae). Mitochondrial DNA B Resour. Feb 9 2021;6(2):475-477. doi:10.1080/23802359.2021.1872432
  7. Yang SY, Choi YR, Lee MJ, Kang MK. Antimicrobial Effects against Oral Pathogens and Cytotoxicity of Glycyrrhiza uralensis Extract. Plants (Basel). Jul 3 2020;9(7)doi:10.3390/plants9070838