Maintaining good oral hygiene is important to many of us for multiple reasons including preventing bad breath and tooth decay.
However, new research has suggested it could have other more far-reaching consequences.
A study, published in the Journal of Neuroinflammation, found that a common oral ailment – gum disease – could trigger dementia, a condition often described as a “silent killer”.
A team from the Forsyth Institute in the US discovered that gum disease, which is also known as periodontal disease in its serious stages, can cause changes in brain cells called microglial cells.
These cells are responsible for defending the brain from amyloid plaque, a type of protein that is associated with cell death, and cognitive decline in people with Alzheimer’s disease.
Study senior author Doctor Alpdogan Kantarci, from the Forsyth Institute, explained: “We knew from one of our previous studies that inflammation associated with gum disease activates an inflammatory response in the brain.
“In this study, we were asking the question, can oral bacteria cause a change in the brain cells?”
The microglial cells studied by the team are a type of white blood cell responsible for digesting amyloid plaque.
Scientists found that the microglial cells became overstimulated and ate too much when exposed to oral bacteria.
Dr Kantarci said: “They basically became obese. They no longer could digest plaque formations.”
He said the finding is “significant” for showing the impact of gum disease on systemic health.
It is thought more than half of adults in the UK suffer from some form of gum disease.
Common signs include gums becoming red, swollen and sore, and bleeding when brushing your teeth.
It can progress to cause the gums to shrink and teeth to fall out.
The disease can also result in lesions developing between the gums and teeth.
“It’s an open wound that allows the bacteria in your mouth to enter your bloodstream and circulate to other parts of your body,” Dr Kantarci said.
He explained that this bacteria can then pass through the blood and brain barrier and stimulate the microglial cells in the brain.
As part of the research, the team tracked the progression of periodontal disease in mice to confirm that the bacteria travelled to the brain.
They then isolated the brain microglial cells and exposed them to the oral bacteria.
The exposure stimulated the microglial cells, activated neuroinflammation and changed how microglial cells dealt with amyloid plaques.
Dr Kantarci added: “Recognising how oral bacteria causes neuroinflammation will help us to develop much more targeted strategies.
“This study suggests that in order to prevent neuroinflammation and neurodegeneration, it will be critical to control the oral inflammation associated with periodontal disease.
“The mouth is part of the body and if you don’t take care of oral inflammation and infection, you cannot really prevent systemic diseases, like Alzheimer’s, in a reproducible way.”
If you experience symptoms of gum disease you should speak to your dentist.
