Despite popular belief, gum disease hasn't been proven to cause atherosclerotic heart disease or stroke, and treating gum disease hasn't been proven to prevent heart disease or stroke, according to a new scientific statement published in Circulation, an American Heart Association journal.

Keeping teeth and gums healthy is important for your overall health. However, an American Heart Association expert committee -- made up of cardiologists, dentists and infectious diseases specialists -- found no conclusive scientific evidence that gum disease, also known as periodontal disease, causes or increases the rates of cardiovascular diseases. Current data don't indicate whether regular brushing and flossing or treatment of gum disease can cut the incidence of atherosclerosis, the narrowing of the arteries that can cause heart attacks and strokes.

Observational studies have noted associations between gum disease and cardiovascular disease, but the 500 journal articles and studies reviewed by the committee didn't confirm a causative link.

"There's a lot of confusion out there," said Peter Lockhart, D.D.S., co-chair of the statement writing group and professor and chair of oral medicine at the Carolinas Medical Center in Charlotte, N.C. "The message sent out by some in healthcare professions that heart attack and stroke are directly linked to gum disease, can distort the facts, alarm patients and perhaps shift the focus on prevention away from well known risk factors for these diseases."

Gum disease and cardiovascular disease both produce markers of inflammation such as C-reactive protein, and share other common risk factors as well, including cigarette smoking, age and diabetes mellitus. These common factors may help explain why diseases of the blood vessels and mouth occur in tandem. Although several studies appeared to show a stronger relationship between these diseases, in those studies researchers didn't account for the risk factors common to both diseases.

"Much of the literature is conflicting," Lockhart said, "but if there was a strong causative link, we would likely know that by now."

A large, long-term study would be needed to prove if dental disease causes heart disease and stroke, he said.

Such a study isn't likely to be done in the near future, and it's most important to let patients know "what we know now, and what we don't know," Lockhart said.

For more than a century, doctors have proposed that infected gums lead to systemic problems like heart disease, and we know that mouth bacteria frequently enter the blood stream during dental procedures and during naturally occurring events such as tooth brushing.

"We already know that some people are less proactive about their cardiovascular health than others. Individuals who do not pay attention to the very powerful and well proven risk factors, like smoking, diabetes or high blood pressure, may not pay close attention to their oral health either" Lockhart said.

Statements that imply a cause and effect relationship between periodontal disease and cardiovascular disease, or claim that dental treatment may prevent heart attack or stroke are "unwarranted," at this time, the statement authors said.

The American Dental Association Council on Scientific Affairs and World Heart Federation endorsed the statement.

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