A research team has carried out a detailed study into mouth bacteria. The researchers were aiming to find out if there was a way of using healthy mouth bacteria as a probiotic in the future. By doing so, it would help healthy bacteria to protect us from tooth decay. This is an important subject area, given the problems that tooth decay cause.
New research has sought to find out more about specific areas of bacteria in our mouths, which has yielded interesting findings [1].
Having a healthy bacterial community in our mouths is important and helps to contribute towards strong oral health and wider wellbeing.
The findings have raised the possibility of healthy mouth bacteria being used as a probiotic to protect against tooth decay and cavities in the future [1].
Background
The key area of the research concerns bacteria and the wider oral microbiome. The oral microbiome refers to the large community of bacteria, viruses, and fungi in our mouth.
Something that many people are unaware of is that there are good types of bacteria – it isn’t all bad. Having a healthy bacterial community in our mouth is important.
However, when the bad bacteria outweigh the good bacteria, problems will occur. For example, teeth will be decay and cavities will develop, which then requires a dental filling.
The researchers were aiming to find a way of distinguishing between these types of bacteria in an effort to boost the proportion of the healthy bacteria. Therefore, this could promote a probiotic oral microbiome [1].
Probiotics are live bacteria and yeasts that have various health benefits [2]. Moreover, probiotics have been growing in popularity, resulting in further interest in this topic.
The Research
The research was carried out by a team from the University of California (UC), Berkeley. Their findings have been published in the Proceedings of the National Academy of Sciences journal [1].
To begin with, the research team pointed out that bacterial species are not uniformly good or bad, instead, it is more nuanced than that.
For example, they noted that individual bacterial species can have hundreds of different varieties (known as strains) [1].
The researchers said that a lot of the past research has been focused on which species or strains caused cavities [1]. However, as mentioned above, it is a more complex topic.
Therefore, the research team decided to focus on the DNA sequences of all the bacteria in the mouth – called the metagenome. They scanned all of these sequences to try and find clusters of genes associated with the development of cavities [1].
The scans involved analyzing an online database of a large number of metagenomic sequences of the microbial communities from the mouths of human volunteers [1].
Once the scans had completed, the researchers were able to identify the clusters associated with oral disease [1].
The researchers were delighted to discover one gene cluster. This cluster produced two molecules that helps the mouth’s community of bacteria to stick together and form a strong biofilm on the teeth – thereby protecting it from decay [1].
Interestingly, the results showed that this gene cluster was found in types of bacteria designated as ‘bad’ bacteria [1]. For example, this included Streptococcus mutans – a well-known type of bacteria that has consistently been linked to tooth decay.
The researchers suggested that this gene cluster could be stuck to good bacteria to overpower bad bacteria [1]. Therefore, this cluster could have a very positive impact on the oral health of humans.
Summary
These are positive findings. The gene cluster discovery is important and has provided researchers with stronger insights into the oral microbiome.
One specific area of success was the decision to focus on DNA sequences rather than specific species or strains – which helped to produce more specialized findings [1].
Wenjun Zhang is a Professor in Chemical and Biomolecular Engineering at UC, Berkeley and served as an author of this research. She commented on the team’s focus on DNA sequences.
Zhang said that upon understanding their activity more, “we can introduce them to the good bacteria so that the good bacteria can now form strong biofilms and outcompete all the bad ones” [3].
Fellow author McKenna Yao reminded us though that “the best way to remove the biofilm on your teeth is to brush” [3]. Remembering the basics is important!
By understanding more about the oral microbiome, it enables researchers to learn more about oral health, which is very positive!
Thinking points…
[1] As Yao pointed out, toothbrushing remains the best way to disrupt the buildup of bacteria in the mouth. Additionally, make sure you attend regular dental check-ups! At a check-up, a dentist can take a thorough look at your oral health and suggest improvements where necessary. They can also provide advice on the oral microbiome! Why not book a check-up now?
[2] There are ways of avoiding or at least accumulating too much bad mouth bacteria. Dry mouth, an unhealthy diet (resulting in food particles needing to be broken down), and dental issues all contribute to the problem. Make sure you brush and floss regularly to lessen the damage caused. Equally, having a healthy diet and drinking plenty of water can be helpful too! Following these steps can produce useful results!
What we offer at Taradale Dental
Taradale Dental is a dental clinic based in Calgary, Alberta, Canada. At our Calgary dental clinic, we provide a range of services for our patients.
We advise our patients to attend our Calgary dental clinic at least twice per year for a regular dental check-up. At these check-ups, we provide a comprehensive review of a patient’s oral health. If any problems are detected, we have many treatments available. For example, these include cavity fillings and root canals. To strengthen your oral health, we recommend brushing your teeth at least twice a day and flossing regularly.
Here at Taradale Dental, we also have some cosmetic treatments available! These include dental implants, teeth whitening and Invisalign™! Our patients find that these treatments have a positive impact on their appearance, confidence and self-esteem.
Moreover, the fees of our treatments at our Calgary dental clinic Taradale Dental are set in line with the Alberta Dental Fee Guide. This ensures transparent and fair pricing, with no hidden costs.
We hope to see you soon at our Taradale Dental clinic in Calgary! You can find out more about us by visiting our website https://taradaledental.ca/!
References
[1] Yao, M. L., Zill, N. A., Barber, C. C., et al. (2025). Synergistic action of specialized metabolites from divergent biosynthesis in the human oral microbiome. Proceedings of the National Academy of Sciences. 122 (34): e2504492122. DOI: https://doi.org/10.1073/pnas.2504492122.
[2] NHS. (2022). Probiotics. Available: https://www.nhs.uk/tests-and-treatments/probiotics/. Last accessed: 8th September 2025.
[3] Sanders, R. (2025). Can the ‘good’ bacteria in your mouth act as probiotic cavity fighters?. https://medicalxpress.com/news/2025-09-good-bacteria-mouth-probiotic-cavity.html. Last accessed: 8th September 2025.
