Oct. 18, 2010 -- Heart attack and stroke risk may rise in the month following invasive dental treatments such as tooth extractions, a study shows.

The risk returns to normal levels within six months, according to the study published in Annals of Internal Medicine.

This is not the first time oral health and heart health have been linked, and the likely culprit is inflammation. The theory is that bacteria from periodontal infection can enter your bloodstream. Once this occurs, the bacteria accumulate along the blood vessels, causing inflammation, which can make people more vulnerable to heart attacks and stroke.

"These findings provide further evidence to support the link between acute inflammation and the risk for vascular events," conclude the study researchers, who were led by Caroline Minassian, MSc, of the London School of Hygiene and Tropical Medicine. "The short-lived adverse effects are nevertheless likely to be outweighed by long-term benefits of invasive dental work."

Researchers reviewed Medicaid claims data of 32,060 adults who had a heart attack or stroke, and then they backtracked to see if the person had undergone any invasive dental procedures. There were 650 people who had a stroke and 525 who had a heart attack after invasive dental work. The researchers took into account other factors known to increase risk for heart attack and stroke, such as diabetes and high blood pressure.

Those who underwent invasive dental work had an increased risk for heart attack or stroke in the four weeks after their procedure, but this risk was "transient," the researchers report.

More than half of the heart attack and strokes seen in the study occurred in women, and 30% in people who were younger than 50, the study showed.