Losing teeth due to gum disease could indicate a person has cardiovascular disease before they show any symptoms, researchers say.
Dental health could be a sign of heart health
US researchers say loss of teeth could be linked to a condition called subclinical atherosclerosis.
This is the build up of potentially harmful plaque deposits in the carotid arteries, which carry blood to the brain. This produces no obvious symptoms, but can lead to serious problems.
The scientists looked at whether the number of missing teeth due to periodontal disease was linked to the amount of plaque in neck arteries.
They studied over 700 men and women aged 55 and older, none of whom had a history of heart disease or stroke.
Doctors gave them dental, physical and neurological examinations, and asked them about their lifestyles and whether they had any habits, such as smoking, which could increase their risk of having cardiovascular disease.
They asked them about their dental hygiene, including how often they brushed and flossed each week.
The patients were also given an ultrasound scan of their carotid arteries.
It was found that those patients who had missing teeth were more likely to have plaque in their arteries.
In those who had lost up to nine teeth, 45% had carotid artery plaque. Just under two-thirds of those with 10 or more teeth missing had plaque build-up in the vessels.
The researchers suggest tooth loss could indicate chronic infection or inflammation of the gums.
Other studies have suggested a link between gum disease and heart attacks and strokes.
Although the reason for the link has not been confirmed, it has been suggested that infections are linked to an increased risk of blocked arteries.
Many of those studied in this research did have other risk factors for cardiovascular disease, such as smoking, poor diet and low levels of physical activity.
But Dr Mo´se Desvarieux, of the University of Minnesota, Minneapolis, who led the research, said tooth loss may be more than a simple marker for lifestyle because the relationship remained after these other factors had been taken into account.
He said: "To our knowledge, this is the first paper to identify a relationship between tooth loss and subclinical cardiovascular disease."
The team are planning to continue the study, enrolling over 1,000 participants, in order to discover more about how tooth loss and cardiovascular disease are linked.
Professor Sir Charles George, medical director of the British Heart Foundation, said: "The BHF welcomes this study investigating the possible links between tooth loss, caused by gum disease, and heart disease.
"Although, this is the first study looking at the correlation between plaque build up in the carotid arteries and the number of missing teeth per subject, it is simply another step forward in scrutinizing the link between the two diseases.
"The BHF will be watching the progression of the study with interest and will be keen to see the final study outcome"
The research is published in Stroke: Journal of the American Heart Association.