Mouth to mouth bacteria transplant may stop dental decay

22 February 2024

University of Adelaide researchers are exploring if a unique transplant moving good bacteria from one person’s mouth to another – possibly through a special toothpaste - could be the answer to improving dental health.

Peter Zilm, a University of Adelaide’s associate professor from the Adelaide Dental School, said, “There are over 700 bacteria that live in the mouth which make up the microbiome. Why some people naturally have a healthy microbiome regardless of whether they go to the dentist regularly or not is a mystery.”

For those of us who do all the right things but still struggle with tooth decay, there may be an interesting solution on the horizon.

An oral microbiome transplant involves taking a sample of plaque bacteria from a super donor – someone who naturally has a healthy microbiome in their mouth – and transplanting it into the mouth of a patient with an unhealthy microbiome.

Peter explained, “An oral microbiome transplant through a specially designed toothpaste or gel could improve dental health. This would be an easy way to boost good bacteria in the mouths of those who don’t have a healthy microbiome, protecting these people against dental decay and the nasty health conditions that can come with it.”

Working in collaboration with Penn State University, researchers have developed a screening tool to identify super donors along with a 3D flow cell which mimics the mouth environment, allowing researchers to maintain the microbiomes taken from super donors.

Peter said, “Our pre-clinical work shows that we can keep at least 250 bacteria that are essential for preventing tooth decay alive for three months in a biobank.”

Early results from a pre-clinical trial have been positive and have shown that the transplant appeared to suppress cavities with no adverse impacts on other parts of the body, such as gut health.

Peter said, “By building a biobank of good bacteria from super donors, we hope to develop a paste containing good bacteria that will hopefully improve the oral health of people who are more susceptible to tooth decay and associated conditions. This could be particularly useful for vulnerable members of our community, such as the elderly and the very young.”

“Having a healthy mouth is crucial for more than just eating and drinking. It’s reflective of our overall health. Poor oral health can even be linked to medical problems such as cardiovascular disease, cancer, and birth complications.”

Experts hope to secure funding to carry out further research into oral microbiome transplants, with the goal of moving to human trials within the next two years.

“If we can show that oral microbiome transplants are safe for humans, they could become a cost-effective solution to one of the nation’s most common chronic illnesses,” said Peter.