Image copyright Getty Images Image caption Tooth decay can lead to cavities forming

Aspirin could reverse the effects of tooth decay and could lead to fewer fillings being needed in the future, researchers in Belfast have said.

Initial research at Queen's University has found aspirin stimulates stem cells in teeth, enhancing tooth regeneration.

Tooth decay, the most common dental disease, leads to the inflammation of the tooth nerve, causing toothache.

The British Dental Association reported in 2016 that 72% of 15-year-olds in Northern Ireland have dental decay.

That figure compared to 44% in England and 63% in Wales.

Aspirin (acetylsalicylic acid) is a drug that has been used for many years as a painkiller. It has an anti-inflammatory action, and is used to relieve headache, menstrual pain and muscle aches. It costs one penny a tablet.

Image caption Tooth decay is usually caused by a build-up of plaque, bacteria in plaque produce acids which weakens the enamel of the teeth

Teeth naturally have limited regenerative abilities. They can produce a thin band of dentine - the layer just below the enamel - if the inner dental pulp becomes exposed, but this cannot repair a large cavity.

Current treatment for tooth decay involves fillings, which may need to be replaced many times during the lifetime of the tooth.

Prof Ikhlas El Karim is a senior lecturer in the School of Medicine, Dentistry and Biomedical Sciences at Queen's University Belfast.

Her research focuses on dental stem cells found in teeth and how dentists can enhance their ability to regenerate and repair damaged teeth, removing the need for fillings.

The research findings, to be presented on Thursday at the British Society for Oral and Dental Research annual conference, show that aspirin can enhance the function of those stem cells, thus helping self-repair by regenerating lost tooth structure.

Image copyright Getty Images Image caption The fact that aspirin is already a licensed drug should help the development of the treatment, the researchers say

"Ideally, what we're really reporting here is that we're hoping to be able to develop a therapy [so] that the teeth could repair themselves," she said.

"This is going to be gradual, it's not going to be the end of the filling straight away."

The researchers collated large amounts of previous research data to indentify aspirin as a compound that can induce the gene signature needed to generate new dentine.

The QUB scientists then treated stem cells in a Petri dish with aspirin and found "genetic and also material evidence that it can produce dentine".

Image copyright Getty Images Image caption Dental decay has long been a problem in children's teeth throughout the UK

"The next step is to go and try to figure out how you are going to apply the aspirin to the teeth, to regenerate the dentine and to replace the need for fillings."

Applying the aspirin to teeth will not involve simply putting it on an infected tooth however.

"You need to put it [on the tooth] in a way that it can be easily released over a long period of time, if you put an aspirin now on a cavity, it's going to be washed away," Dr El Karim said.

"We are not encouraging that, there is a scientific way to go about this, so that we produce a final product that can be used by a dentist, not by a patient.

Image copyright Getty Images Image caption Fillings may need to be replaced many times during the lifetime of the tooth

"The next step is to work with our pharmacy colleagues to try to develop a vehicle to put it in to the teeth, after that clinical trials."

Dr El Karim said the fact that aspirin is already a licensed drug should help the development of the treatment.

"We are not really talking about 10 or 20 years time, it will probably be in the near future that it could be tried in a clinical trial with patients," she said.

"There is huge potential to change our approach to one of the biggest dental challenges we face.

"This novel approach could not only increase the long-term survival of teeth, but could also result in huge savings for the NHS and other healthcare systems worldwide."