Sprawled on your back in the dental chair, your mouth wide open, what can you say when your dentist reminds you that you need to floss? When she points to an article on the wall and tells you that periodontal disease may be linked to an increased risk of heart disease, you may even be spurred to action.

Periodontal disease is a chronic infection of the gums that results from an accumulation of plaque on the teeth and under the gums. If left untreated, gums are likely to become sore and bleed when brushed...and especially when they are subjected to the thorough cleaning performed by a dental hygienist. Eventually, pockets of infection will form, and bone surrounding the tooth will be destroyed, leading eventually to tooth loss.

None of the above need happen, of course, if you brush your teeth at least twice a day, floss them daily and have them cleaned regularly by a dental hygienist.

Most Americans see the value of good dental care, even if they occasionally neglect to floss. “Floss only the teeth you want to keep,” reads the sign in the dentist’s office. But heart disease is an even more serious matter; you have only one heart to lose.

The link between infected gums and heart disease is a fairly recent development, and researchers are still debating the evidence. The facts are strong enough, however, to make many Americans think more seriously about flossing.

Chronic Infection Is Risk
The idea that chronic infection or inflammation may play a major role in the development of heart disease is gaining favor among researchers. Individuals with even slightly elevated levels of C-reactive protein, a substance produced by the liver in response to tissue inflammation, have an increased risk of heart disease regardless of age, sex, general health and other risk factors. Other studies have indicated that the body’s response to infection or inflammation may be a major factor in the buildup of plaque in coronary arteries.

Periodontal disease is the most common chronic infection, affecting at least a third of adults over age 30, and it has been linked with other health problems such as pre-term birth, lung disease and type 2 diabetes. Scientists theorize that bacteria present in the gums may enter the blood stream and migrate to coronary arteries, triggering an inflammatory response that could injure the delicate walls of arteries and lead to the development of heart disease.

Organisms generally present in diseased gums have been found in plaque deposits in coronary arteries. Scientists believe these organisms in the blood stream may trigger the liver to produce C-reactive proteins.

One study found that enzymes produced by a periodontal bacterium stimulated the formation of blood clots in a test tube. Animals injected with this organism developed symptoms of a heart attack.

Starting with a Finnish study in 1989, several researchers have found a correlation between periodontal infections and heart disease. One study found that males with large amounts of bone loss due to periodontal disease were about twice as likely as other subjects to have a fatal heart attack. A 1998 meta-analysis concluded that gum disease doubled the risk of coronary artery disease, but a more rigorously designed meta-analysis published the following year found an increased risk of only about 24 percent.

Many of the early studies were flawed, and a study published in the Journal of the American Medical Association [September 20, 2000] found only a 2.7 percent correlation between heart disease and severe gum disease and no correlation with mild gingivitis.
Whatever correlation, if any, might exist, it does not, of course, establish a cause/effect relationship. Persons who are conscientious about flossing may also be more likely to exercise and eat a healthy diet.

Smoking is a frequent cause of periodontal disease, and so far no studies have linked heart and gum disease in persons who have never smoked. Periodontologist Philippe Hujoel of the University of Washington, Seattle has pointed out that periodontal disease is associated with all diseases related to smoking. Dr. Hujoel’s study of smoking, periodontal infection and heart disease is due to be published in October, 2002.

Skeptics point to the fact that persons who have had all their teeth pulled–and therefore have no periodontal disease–have a risk of heart disease similar to that of persons with periodontal disease. Toothless individuals, however, likely had uncontrolled gum disease for some time before their teeth were pulled.

A study of health professionals found a correlation between gum infections and heart disease only in men with periodontal disease and 10 or fewer teeth.

Some researchers believe the link between poor oral health and heart disease might be attributed to diet. A study by Dr. Kaumudi Joshipura of the Harvard School of Dental Medicine and the Harvard School of Public Health, found that individuals who had lost all of their teeth ate fewer vegetables and less fiber while consuming more cholesterol, saturated fat and calories.

Will Treating Gums Help?
Some answers regarding cause and effect may be provided through a 27-month study, Periodontal Intervention in Cardiovascular Disease (PAVE), that will start in September, 2002. It will study the effect of treating periodontal disease among subjects who have a 50 percent blockage in one or more arteries, have had a heart attack or have undergone heart surgery.

One small study recently found that periodontal treatment had a positive effect on the walls of blood vessels. Preliminary results of ongoing studies suggest that treatment of gum disease may reduce blood levels of C-reactive protein.

If you’re looking for a way to protect yourself from heart disease, there is no proof at this time that periodontal treatment will do the trick. Having healthy gums and teeth is, on the other hand, a worthy goal in itself. There is no harm and much to be gained from diligent flossing and regular visits with your dentist and dental hygienist.

REFERENCES:
Suzan Abou-Raya, Amr Naeem, Hassan Abou-El Kheir and Sheriff El Beltagy, “Coronary Artery Disease and Periodontal Disease: Is There a Link?” Angiology, March, 2002.
“Blood Vessels Found To Signal Chain of Destruction,” Angiogenesis Weekly, July 27, 2001.
“Chronic Periodontal Disease May Be Risk Factor (for Type 2 Diabetes),” Health & Medicine Week, May 7, 2001.
Robert J. Genco, Maurizio Trevisan, Tiejian Wu, James D. Beck, Philippe P. Hujoel, Mark T. Drangsholt, C. Spiekerman, Timothy A. DeRouen, “Periodontal Disease and Risk of Coronary Heart Disease,” JAMA, January 3, 2001.
“Gum Disease and CHD,” The Johns Hopkins White Papers, Coronary Heart Disease, 2001.
C.W. Henderson, “Gum Disease Not Risk Factor for Cardiovascular Disease,” Health & Medicine Week, February 12, 2001.
“Philippe P. Hujoel, Mark Drangsholt, Charles Spiekerman and Timothy A. DeRouen,” Periodontal Disease and Coronary Heart Disease Risk,” JAMA, September 20, 2000.
Robert B. Johnson, “Your Teeth & Your Health,” Health Science, Spring, 2001.
“Maintaining Healthy Teeth and Gums,” Mayo Clinic Health Letter Medical Essay, June, 2002.
Marilynn Larkin, “Can Flossing Teeth Foil Heart Disease?” The Lancet, July 13, 2002.
Norra MacReady, “Periodontitis Linked to Renal Insufficiency,” Internal Medicine News, December 1, 2001.
“More Evidence that Periodontitis May Be a Risk Factor for Heart Disease,” Imunotherapy Weekly, June 19, 2002.
“Oral Health and Heart Disease,” Harvard Heart Letter, March, 2001.
Jim Ruskin, Stephen Porter, Heft Marc and Joseph Katz, “Inflammation, Periodontitis, and Coronary Heart Disease,” The Lancet, December 8, 2001.
Harold C. Slavkin and Bruce J. Baum, “Relationship of Dental and Oral Pathology to Systemic Illness,” JAMA, September 13, 2000.
“Study Shows Antiobiotic Effectiveness as Adjunctive Treatment,” Health & Medicine Week, January 21, 2002.
Tiejian Wu, Maurizio Trevisan, Robert J. Genco, Joan P. Dorn, Karen L. Falkner and Christopher T. Sempos, “Periodontal Disease and Risk of Cerebrovascular Disease: The First National Health and Nutrition Examination Survey and Its Follow-Up Study,” Archives of Internal Medicine, October 9, 2000.