The mouth is the window to the body. It is both an indicator of the body's overall health, and a potential starting point for inflammation of the gums (periodontal disease), which affects three out of four adults age 35 and over, according to the Centers for Disease Control and Prevention. Several theories exist to explain the link vetween periodontal disease and heart disease. One theory is that oral bacteria can affect the heart when they enter the blood stream, attaching to fatty plaques in the coronary arteries (heart blood vessels) and contributing to clot formation. Coronary artery disease is characterized by a thickening of the walls of the coronary arteries due to the buildup of fatty proteins. Blood clots can obstruct normal blood flow, restricting the amount of nutrients and oxygen required for the heart to function properly. This may lead to heart attacks.

Another possibility is that the inflammation caused by periodontal disease increases plaque build up, which may contribute to swelling of the arteries.

Researchers have found that people with periodontal disease are almost twice as likely to suffer from coronary artery disease as those without periodontal disease.

Periodontal disease not only causes tooth loss-researchers have also linked it to heart disease, stroke, diabetes, respiratory problems, and premature birth. Conversely, researchers are making the connection that these diseases can make an individual more susceptible to periodontal disease.

In some cases, the first signs of systemic disease-diseases that affect the entire body-may be seen in the mouth. For example, periodontal disease that does not respond to traditional therapies could be an early indicator of diabetes. Pale gums could be a symptom of leukemia. Oral lesions often are an early sign of the HIV-virus infection.

Major research studies continue in an effort to learn more about the link between periodontal disease and other systemic diseases. Earlier this year, for example, researchers from the University of Minnesota and Columbia University reported that older adults who have higher proportions of four periodontal-disease-causing bacteria in their mouths also tend to have thicker carotid arteries-a strong predictor of stroke and heart attack.

In addition, researchers at the U of M and several other medical centers, led by the University's Bryan Michalowicz, are involved in a major study of more than 800 pregnant women with periodontal disease to find out if they are more likely to deliver preterm, low-birth weight babies. The researchers want to find out if treating expectant mothers¿ gum disease will reduce the incidence of premature births.

When your mouth and teeth are disease-free, your risks for developing other diseases throughout your life may be reduced. You can help prevent gum disease by brushing and flossing every day, limiting between-meal snacks and seeing your dentist and dental hygienist regularly. Good oral hygiene will keep bacteria in the mouth at relatively low levels, preventing the build-up that leads to disease.

Parts of this article were written by Larry Wolff, Ph.D., D.D.S.