Effect of liquorice (root extract) mouth rinse on dental plaque and gingivitis - A randomized controlled clinical trial

J Indian Soc Periodontol. 2022 Jan-Feb;26(1):51-57. doi: 10.4103/jisp.jisp_517_20. Epub 2022 Jan 1.

Abstract

Background: Around the world, an increasing number of people are turning towards nature by using the natural herbal products not only because they are inexpensive but also for better cultural acceptability, better compatibility with the human body and minimal side effects. This study assessed the effectiveness of liquorice (root extract) mouth rinse against dental plaque and gingivitis and compared it with 0.2% chlorhexidine (CHX) gluconate mouth rinse.

Materials and methods: A double-blind, concurrent parallel randomized controlled clinical trial (CTRI/2016/09/007311) of four months duration was conducted. Forty-four volunteers who met the inclusion criteria were randomized into two groups through the computer-generated random sequence. Based on in vitro minimum inhibitory and minimum bactericidal concentration evaluations on periodontal pathogens, a concentration of 20% (w/v) of aqueous liquorice root extract mouth rinse was prepared. Both the groups were asked to rinse with their respective mouthwash twice daily for 15 days. Gingivitis was evaluated using gingival index (GI), and dental plaque was evaluated using the Turesky modification of the Quigely Hein Plaque Index (PI). The evaluation was carried out at day zero, 8th and 23rd (15 days after intervention). Intra- and intergroup comparisons of indices for both the arms were done using the paired sample t-test and unpaired t-test, respectively.

Results: There was a statistically significant (P = 0.000) reduction in mean PI and GI scores for both the groups after a follow up of 15 days. The intergroup comparison of plaque and gingival index scores for both the mouth rinse groups came out to be statistically significant (P = 0.000).

Conclusion: Both liquorice and CHX gluconate mouth rinse restricted plaque accumulation and gingival inflammation. Considering the established side effects of long-term use of chemical formulations, the herbal mouth rinse preparation can promise to be an effective self-care therapy.

Keywords: Chlorhexidine; gingivitis; herbal; liquorice; plaque index.