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With the NHS dental system under strain, emergency hubs provided by the charity Dentaid are offering alcohol-free OraWize+ mouthwash to counter the effects of poor oral health and gum disease. And since the start of the COVID-19 pandemic, other benefits of mouthwash use are emerging too.  

As dental practices began to re-open in the summer of 2020, COVID-19 precautions meant a major reduction in capacity for NHS providers. Everyday hygiene measures were ramped up to minimise transmission between patients and dental teams, and any aerosol-generating procedure became a logistical nightmare. Preventative dentistry like dental hygiene visits and regular check-ups were deprioritised to make way for emergency treatment.  

And though the crisis point has passed, the pressure is still high in many parts of the country with practices struggling to meet the demand for treatment.  

Dentaid’s mobile units are helping to tackle the impact of the pandemic on the nation’s oral health, thanks to dental professionals who volunteer their time and skills to the charity. Alex Setchell, Principal Dentist at Dentaid’s Bournemouth hub, gives a day each month to the service.  

“Here on the Dentaid bus, we give OraWize+ away to our clients when we’ve completed dental work,” he says. “It’s effective for this kind of setting because it’s alcohol-free, and the patients like it because they can rinse with something that will help, even if they don’t want to clean their teeth.” 

A recent review [1] confirms that using mouthwash is an effective way to remove dental plaque, and for patients unable to maintain habits like brushing or flossing, it can offer a quick, easy alternative that helps to reduce the risk of developing gum disease.  

But it turns out there may be other benefits to using mouthwash that have far wider implications for public health. Research has uncovered a link between oral health and the severity of COVID-19.  

Using mouthwash may help to reduce the viral load in the oral cavity, meaning viral particles are less likely to enter the bloodstream through the gums of patients with periodontal disease. 

The link between COVID-19 and periodontitis 

As we know, COVID-19 usually causes mild to moderate symptoms ranging from a runny nose and continuous cough to fever and fatigue. But a small number of infections lead to more severe disease and can prove fatal.  

Typically, we think of respiratory viral infections entering the lungs through inhalation, but scientists are exploring other ways viruses might move through the body to infect our organs. The mouth, in particular, may play a bigger part [2] than we first realised.  

In 2020, scientists in Qatar noticed that many of the risk factors for severe COVID-19 – diabetes, hypertension, age, and smoking – were also common in patients with periodontal disease. In a study [3] of 568 COVID-19 patients, those with periodontal disease were 3.5 times more likely to be admitted to an intensive care unit, 4.5 times more likely to be put on a ventilator and 8.8 times more likely to die.  

SARS-Cov-2 and the mouth 

We’ve known since 2020 that the SARS-Cov-2 virus is present in saliva, but scientists were unsure if it could infect oral tissues. The oral cavity is protected by a range of immune defence mechanisms [4] from antimicrobial substances to hundreds of species of ‘friendly’ bacteria that regulate the mouth’s microbiome.  

Like all coronaviruses that cause disease in humans, SARS-Cov-2 can ‘unlock’ human cells, hijacking their functions to manufacture and release new viral particles. Using a specialised spike protein, SARS-Cov-2 can bind to receptors on cell surfaces and sneak inside where it can replicate.  

Unfortunately for us, studies have shown that cells in the mouth express enzymes that are essential for this process [5]. That means oral tissue can act as potential sites for viral infection. And the sulcular epithelium – where tooth meets gum – is a prime location. In a recent clinical study [6] of COVID-19 patients, over half displayed high levels of viral replication in the salivary glands and mucosa.  


From the mouth to the lungs – Dr Lloyd-Jones’ research 

To find out more, a research team led by radiologist Graham Lloyd-Jones explored patterns of lung damage [7] in severe COVID-19 patients with either periodontal disease or poor oral health.  

From CT scans of the lungs, researchers noted that opaque areas with a ‘ground glass’ appearance – a hallmark of lung damage – were concentrated at the base of the lungs. This was a tell-tale sign that the virus was entering via the vascular system, since purely inhaled pathogens should create an even spread of lung damage. 

When levels of SARS-Cov-2 in saliva are high, any breach in the oral immune defences might allow the virus to enter the bloodstream through the soft tissues of the oral cavity. Poor dental hygiene, dental plaque, inflammation, and periodontal wounds all contribute to the risk. Once in the bloodstream, the virus is then thought to travel through the heart and into the lungs. 

These findings could change our understanding of how multiple diseases develop. Saliva might play a role in transporting pathogens to the digestive system, potentially contributing to other conditions such as inflammatory bowel disease, pneumonia, and arthritis. Non-irritating, non-toxic mouthwash products – unlike those which can harm cells [8] – could work in harmony with your body to help defend it from disease. 

The solution: mouthwash? 

With dental hygiene visits and check-ups still out of reach for many patients, regular mouthwash use might be a simple and effective way to protect against viruses like SARS-Cov-2.  

A recent study [9] suggests that a HOCl based mouthwash is highly effective at reducing levels of SARS-Cov-2 in the oral cavity and therefore would help keep viral levels suppressed in aerosols for short periods, thereby reducing cross infection risk. And according to 2 separate pieces of research supported by J & J and Public Health England [10] the hypochlorous acid-based mouthwash Orawize+, the brand handed out from Dentaid buses to vulnerable patients was especially effective against the virus. What is especially interesting is there are a number of studies showing 90% load suppression after 15 and 30 minutes [11]. 

Controlling gum disease is more important than we ever thought 

Engaging patients in good oral hygiene practices is even more critical than we realised, since it could help reduce the impact of COVID-19 and other diseases. The wide-spread use of a preprocedural mouthwash irrigant in dentistry provides a number of benefits to both patients and dental staff: by reducing microbial populations and reducing ‘routes in’ for pathogens afterwards, as well as helping reduce cross infection risks for frontline staff. 


[1] An update on the efficacy of mouthwash use. (2022). British Dental Journal, 233(8), 693–693.https://www.nature.com/articles/s41415-022-5192-8

[2] Nguyen. (2021). Investigating the mouth–COVID connection. Nature (London). https://doi.org/10.1038/d41586-021-02922-8

[3] Marouf, Cai, W., Said, K. N., Daas, H., Diab, H., Chinta, V. R., Hssain, A. A., Nicolau, B., Sanz, M., & Tamimi, F. (2021). Association between periodontitis and severity of COVID‐19 infection: A case-control study. Journal of Clinical Periodontology, 48(4), 483–491. https://doi.org/10.1111/jcpe.13435 

[4] Şenel. (2021). An Overview of Physical, Microbiological and Immune Barriers of Oral Mucosa. International Journal of Molecular Sciences, 22(15), 7821–. https://doi.org/10.3390/ijms22157821 

[5] Sakaguchi, Kubota, N., Shimizu, T., Saruta, J., Fuchida, S., Kawata, A., Yamamoto, Y., Sugimoto, M., Yakeishi, M., & Tsukinoki, K. (2020). Existence of SARS-CoV-2 Entry Molecules in the Oral Cavity. International Journal of Molecular Sciences, 21(17), 6000–. https://doi.org/10.3390/ijms21176000 

[6] Huang, N., Pérez, P., Kato, T. et al. SARS-CoV-2 infection of the oral cavity and saliva. Nat Med 27, 892–903 (2021). https://doi.org/10.1038/s41591-021-01296-8 

[7] Lloyd-Jones, G., Molayem, S., Pontes, C. C., & Chapple, I. (2021). The COVID-19 Pathway: A Proposed Oral-Vascular-Pulmonary Route Of SARS-CoV-2 Infection and The Importance of Oral Healthcare Measures. Journal Of Oral Medicine and Dental Research, 2(1), 1–25. https://doi.org/10.52793/JOMDR.2020.2(1)-13 

[8] Kőhidai, Z., Takács, A., Lajkó. E., et al. (2022). The effects of mouthwashes in human gingiva epithelial progenitor (HGEPp) cells. Clinical Oral Investigations, 26(6):4559-4574. https://doi.org/10.1007/s00784-022-04422-z 

[9] Chaudhary, P., Melkonyan, A., Meethil, A., Saraswat, S., Hall, D. L., Cottle, J., Kumar, P. (2021). Estimating salivary carriage of severe acute respiratory syndrome coronavirus 2 in non-symptomatic people and efficacy of mouth rinse in reducing viral load: A randomized controlled trial. The Journal of the American Dental Association, 152(11), 903-908. https://www.sciencedirect.com/science/article/abs/pii/S000281772100355X 

[10] Seymour. D, Davies, K., Buczkowski, H., Welch, S. R., Green, N., Mawer, D., Woodford, N., … & Killip, M. J. (2020). Effective in-vitro inactivation of SARS-CoV-2 by commercially available mouthwashes (preprint). https://pubmed.ncbi.nlm.nih.gov/33913803/ 

[11] Silva et al. J Am Dent Assoc. (2022). The effect of mouth rinses on severe acute respiratory syndrome coronavirus 2 viral load: A systematic review. https://www.sciencedirect.com/science/article/pii/S0002817721007868