Effects of a mouthwash containing Lespedeza cuneata extract on risk of dental caries: a randomized, placebo-controlled clinical trial

This study aims to evaluate the anti-caries effect of a mouthwash containing Lespedeza cuneata extract by confirming its effect on acid-producing capacity and bacteria causing dental caries in the oral cavity. For the same oral environments of 95 subjects who agreed to participate in this study, scaling was performed one week before the experiment. The final number of subjects included in the analysis was 82, excluding those who dropped out during the study period. A randomized placebo-controlled trial was conducted by dividing the subjects into the Lespedeza cuneata extract gargle group (n = 42) and the saline gargle group (n = 40). Participants in each group gargled once every day before going to bed for 5 days, and data were collected by measuring 3 times: before gargling (Baseline), immediately after gargling (Treatment), and 5 days after gargling (After 5 Days). Two trained dental hygienists confirmed the dental caries activity through the Cariview test under the guidance of a dentist. Microbiological analysis was performed to evaluate the changes in bacteria causing dental caries. By confirming the anti-caries effect in the oral environment according to the application of Lespedeza cuneata extract gargle, dental caries activity was found to be significantly lower from Treatment to After 5 Days (p < 0.05). Dental caries-causing bacteria in the upper and lower jaws were also significantly reduced (p < 0.05). These results confirm that Lespedeza cuneata extract is a natural substance with an anti-caries effect. Gargling with a mouthwash containing Lespedeza cuneata extract is useful in preventing dental caries and inhibiting its progression. The same mouthwash can also be used as an effective formulation for maintaining and promoting oral health.