Hydrogen Water Mouthwash Fights Tooth Decay-Causing Bacteria
- Authors
- Ha-Young Youn, Ji-Hye Kim, Min-Jeong Cho, Su-Hyung Hong, Eun-Kyong Kim
- Journal
- Journal of Yeungnam Medical Science
- Year
- 2025
- DOI
- 10.12701/jyms.2025.42.34
- Study Type
- Human
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- South Korea
- Health Condition
- Dental Caries
- Body System
- Oral Health
TL;DR
Rinsing with hydrogen-rich electrolyzed water (HEW) can reduce dental plaque and the bacteria that cause it, making it a promising alternative to traditional mouthwash.
Key Finding
Hydrogen-rich electrolyzed water used as a mouthwash significantly reduced Streptococcus mutans bacteria and plaque buildup in a small human trial of 24 participants.
Summary
Researchers tested hydrogen-rich electrolyzed water (water treated with electricity to add hydrogen) as a mouthwash against Streptococcus mutans, a bacteria linked to tooth decay. In lab tests, the hydrogen-rich water reduced biofilm (sticky bacterial layers) formation without killing the bacteria itself. When 24 people used it as a mouthwash twice daily, they had fewer of these bacteria in their saliva and less plaque buildup compared to those using regular tap water.
Practical Takeaway
This small study suggests hydrogen-rich water may help reduce cavity-causing bacteria and plaque when used as a mouthwash, though the trial involved only 24 people and longer-term safety and effectiveness data are not yet available. More research with larger groups and longer follow-up periods would be needed to confirm whether this could be a practical alternative to conventional mouthwashes.
Abstract
Background: Previous studies have demonstrated the inhibitory effect of hydrogen-rich water on biofilm formation. However, hydrogen-rich electrolyzed water (HEW) has not been evaluated as mouthwash, despite being economical, convenient, and biologically safe. We assessed the antibiofilm effects of HEW on Streptococcus mutans and its potential as a mouthwash. Methods: The effect of HEW on S. mutans growth was assessed by measuring bacterial colony-forming units, and biofilm formation capacity was examined by crystal violet staining after culturing on a polystyrene plate. The effect of HEW on biofilm formation-related gene expression in S. mutans was assessed by real-time polymerase chain reaction. Finally, the effect of HEW on salivary S. mutans and plaque maturation was evaluated in 24 participants; after gargling with HEW twice daily, the salivary S. mutans count was quantified using a Caries Risk Test bacteria kit (Ivoclar Vivadent AG), and plaque maturation was compared using quantitative light-induced fluorescence imaging. Results: Exposure to HEW resulted in no significant changes in S. mutans growth but a significant reduction in biofilm formation in vitro (p<0.001). Furthermore, the gene expression of glucosyltransferases (gtfB, gtfC) was significantly lower than that in the control group treated with tap water (p<0.05, p<0.01). S. mutans counts and plaque maturation were significantly lower in participants who gargled with HEW than in those who gargled with tap water (p<0.01). Conclusion: Our data suggest that oral rinsing with HEW exerts antibiofilm effects on S. mutans, indicating that it can be used as a mouthwash to treat dental biofilm-dependent diseases.