Good dental hygiene is crucial in the fight against gum disease, which can lead to a common condition called periodontitis. It comes about when changes to the bacteria in the mouth cause a reaction called inflammation in areas around the teeth, potentially destroying tissue and bone and causing tooth loss. But quite why an altered microbiome causes this inflammation isn't known, so there are no targeted treatments, and surgery is the main option for severe cases.

But now scientists have spotted that periodontitis patients have higher numbers of immune cells called TH17 cells in their mouths, and by targeting these cells, they managed to slow down the progression of the disease in mice. Katie Haylor spoke with Niki Moutsopoulos from the National Institute of Dental and Crano-facial Research at the National Institutes of Health in Bethesda, Maryland.