Recent research has found that people with periodontal disease or a buildup of plaque in their arteries (atherosclerosis) have similar bacteria in their bloodstreams, reinforcing the connection between these conditions, experts said at a media briefing February 23. The briefing, hosted by the American Medical Association and American Dental Association, also covered apparent links between poor dental health and pregnancy complications and the increased risk of periodontal disease for diabetics. A new study presented at the briefing found that smoking may raise the risk of needing a root canal treatment.

By Mary Pickett, M.D.
Harvard Medical School

What Is the Doctor's Reaction?

Could poor dental health cause heart disease or strokes? So say experts from the American Medical Association and the American Dental Association, who held a joint news conference to explore the connection between the health of the mouth and the health of the body.

We are dramatically shifting our understanding about the causes of heart attacks and strokes. It is old news that smoking, hypertension, cholesterol, inactivity, diabetes, age and family history all correlate with a higher heart attack risk and risk for atherosclerosis.

It has been newer news within the last several years that longstanding, mild inflammation in the body is also linked to heart attack and stroke risk. Inflammation is a sign of an activated immune system, and an active immune system creates chemical changes in the bloodstream that can make arteries more likely to clog or clot.

Researchers have been on the hunt for sources of long-term, low-grade inflammation that may lead to heart disease or strokes. A growing collection of evidence points toward poor dental health as an important source of inflammation and a contributor to artery disease.

Two years ago, a study published in the journal Circulation showed that tooth decay and gum irritation were both more common in patients with heart disease, and were more common in people with elevated C-reactive protein (CRP) tests. This test detects subtle bloodstream inflammation and can predict heart attack and stroke risk.

Just two weeks ago, Circulation published a new study about oral health and artery disease. More than 650 adults over age 55 were studied. None of these adults had ever been diagnosed with heart disease or stroke.

Plaque samples from teeth at the back of the mouth were collected, and the concentration of bacteria in the plaque was measured. A neck ultrasound was used to check for cholesterol deposits in the carotid arteries, evidence of atherosclerosis.

Low, medium, and high bacteria counts in dental plaque matched up with an increasing average thickness of cholesterol deposits in the carotid arteries. This connection was true whether or not the person smoked, had diabetes, or had other traditional risk factors for atherosclerosis.

What Changes Can I Make Now?

Good dental care is excellent medicine, and the possible connection between oral health and risk for heart attacks and strokes is a great reason to update your oral health with a visit to your dentist. It is particularly important for you to get regular care if you have diabetes or if you are a smoker -- these two problems increase your risk for heart disease, but they also make you more likely to have dental needs and oral health conditions.

What Can I Expect Looking to the Future?

The idea that dental health might affect your risk for heart disease or stroke certainly will be explored further with additional research.

What we know so far is a great start, since we have identified a connection, but we can't quite be certain that periodontal disease is a direct cause of artery issues. It is possible that an entirely separate factor, such as low income status or poor nutrition, is the reason that dental problems and artery problems occur in the same people.

The research that really matters has yet to be done. Can providing regular dental cleanings and good dental hygiene prevent heart attack and stroke events? Answering this question will require a well-funded study -- we will need to "put our money where our mouth is," providing top-quality dental care to a large study group. Then, if we see that we can lower heart attack or stroke risk, we will have something to smile about.

Learn More: Read a dentist's viewpoint on the connections between medical and dental health.