Dentists who harp their patients about brushing their teeth before bed could have hit at the heart of another problem — literally.
According to University research unveiled at a conference in Philadelphia on Monday, plaque on teeth can contribute to blood clots and other heart ailments.
University professors Mark Herzberg and Maurice Meyer found the bacteria in dental plaque can cause the blood clots that precede heart attacks and other coronary ailments.
“These bacteria do not produce heart attacks,” said Meyer, a professor emeritus of oral sciences, neurology and physiology. “But they may influence the other factors that are involved in initiating heart attacks.”
Using rabbits as test samples, Herzberg and Meyer discovered that bacteria found in plaque can cause blood platelets to clot.
Dental plaque is caused by bacteria left over from food particles that decay in the mouth, Meyer said. Plaque, if it goes untreated, can develop into gum disease, an infection of the gums. Because the gums are infected, bleeding often ensues when teeth are brushed.
This bleeding allows bacteria from the plaque to enter the blood stream through the infected gum’s blood vessels. This bacteria could cause the platelets to clot and restrict blood flow to the heart and other areas.
“This may explain why the first hour after people wake up is the most common time for myocardial infarctions (heart attacks),” said Herzberg, a professor of preventative sciences. “That is when we brush our teeth.”
Plaque build-up is at one of its worst points in the morning, Meyer said.
But all people aren’t at risk if plaque builds up and bacteria goes into the bloodstream after brushing, dentists said. “In most instances, for people with healthy gums, there would be no problem,” Meyer said.
Those with prior heart conditions are putting themselves more at risk if they let plaque build up. Because the bacteria causes clotting, restricted blood flow caused by smoking or high cholesterol can be amplified.
Dentist Richard Barr of Blaine, Minn., said dentists have known of the connection between the dental plaque bacteria and possible heart problems for 20 years. He said patients with heart valve problems often need to be pre-medicated prior to dental work.
Barr said he worries that previously published reports could scare people into not brushing their teeth because the bacteria would be emitted. He said he believed the survey said people with heart ailments needed to keep their mouths cleaner to prevent complications.
But a local newspaper didn’t leave that impression, he said.
“The paper tried to sensationalize it by saying, `If you brush your teeth in the morning it could cause a heart attack,'” Barr said. “I don’t think that was what the study was trying to say at all.”
Barr said the best way to prevent plaque build-up is to maintain good hygiene by brushing teeth regularly or using a mouth rinse.
And for Meyer and Herzberg, this could be the first step toward further findings. The pair hopes to study the connection in more long-term studies in varying conditions.

— The Associated Press contributed to this report.