Brushing your teeth could reduce the risk of having a stroke or heart attack, a study has suggested.
Could this be a weapon in the fight against heart disease?
A team from Columbia University found people with gum disease were more likely to suffer from atherosclerosis - a narrowing of blood vessels.
The condition can precede a stroke or heart attack.
The British Dental Association said the research, published in the journal Circulation underlined the importance of looking after dental health.
The Columbia researchers looked at levels of bacteria in the mouths of 657 people who had no history of stroke or myocardial infarction (heart attack).
The researchers also measured the thickness of the subjects' carotid artery, which carries blood from the heart to the brain, and which is measured to identify atherosclerosis.
It was found that those people who had a higher level of the specific bacteria that causes gum (periodontal) disease also had an increased carotid artery thickness, even after taking other cardiovascular risk factors into account.
The team also found that the link with atherosclerosis only existed for the bacteria which was known to cause gum disease, and not other bacteria found in the mouth.
The researchers said the explanation may be that this bacteria migrates throughout the body via the bloodstream and stimulates the immune system, causing inflammation that results in the clogging of arteries.
The link between poor dental health and poor vascular health has been suggested before.
But Dr Mo´se Desvarieux, of Columbia University Medical Center's Mailman School of Public Health, who led the study, said: "This is the most direct evidence yet that gum disease may lead to stroke or cardiovascular disease.
"And because gum infections are preventable and treatable, taking care of your oral health could very well have a significant impact on your cardiovascular health."
He added: "We will continue to study these participants to determine if atherosclerosis continues over time and is definitely associated with periodontal disease."
Judy O'Sullivan, medical spokesperson for the British Heart Foundation said: "Inflammation may prove to be a key factor in the development of coronary heart disease.
"However, it may be too simplistic to say that periodontal infection alone is the issue of concern rather than inflammation in general, as inflammation is often associated with other risk factors for coronary heart disease, such as smoking, poor diet and low income."
She added: "We welcome studies which add evidence to this growing area of research and we would encourage people to follow a healthy lifestyle to reduce their risk of heart disease.
"This includes maintaining healthy teeth and gums as well as not smoking, taking regular physical activity and enjoying a balanced diet."
A spokesperson for the British Dental Association added: "A number of studies in the past have suggested a link between gum disease and heart disease and this research would seem to strengthen that link.
"It also underlines the importance of brushing twice a day with a fluoride toothpaste to reduce the risk of gum disease and improve overall dental health."