Mouth watch

The way to a person’s heart is through his stomach, the adage goes. But researchers now think the way to a healthy heart might be through your gums and teeth.

Evidence suggests that the healthier they are, the stronger and less disease-prone the heart is. If you don’t floss or brush, you might be setting yourself up not just for gum disease but also for heart disease.

The link between what’s happening in your mouth and in the rest of your body goes further still: Gum disease might be a kind of early warning system, with poor oral health linked to diabetes, kidney disease, preterm labor, osteoporosis, Alzheimer’s disease and even certain types of cancer.

“A lot of research studies are coming out that seem to suggest some possible link or associations” between oral infection and systemic disorders, says Sally Cram, a periodontist in the District of Columbia and consumer adviser for the American Dental Association.

There’s a certain logic, of course, to the idea that your mouth – your body’s key opening to the outside – would be a harbinger of bodily health. Yet the connection is one that many people, even medical professionals, often overlook.

Patients tend to minimize oral health, treating mouth issues as merely “dental.” Professionals echo this artificial dichotomy: Dentists and doctors don’t really talk to each other; they don’t attend the same conferences; they don’t read the same journals.

But recent research indicating a link between their disciplines is attracting attention from both doctors and dentists. Several studies show a startling correlation between gum health and atherosclerosis, a condition underlying much heart disease: The worse a person’s gum disease, the narrower that person’s arteries due to a buildup of plaque. This holds even for young, healthy adults who have no other symptoms of heart disease.

Many questions remain about the nature of the body-mouth connection.

In gum disease (called gingivitis in the early stages, before it develops into full-blown periodontal disease), the tissue that surrounds the bones supporting the teeth become inflamed or infected. Often this results from the accumulation of bacteria in the plaque under the tissue holding the teeth. The bacteria release toxins and other chemicals that begin to destroy the bone. Scientists believe they circulate and cause damage elsewhere in the body; exactly how remains unclear.

“It is like setting up a garbage dump on the edge of a river. You wouldn’t be surprised if the lake downstream ended up polluted with the garbage from the dump,” Vincent J. Iacono said in 2005, when he was president of the American Academy of Periodontology.

When Maurizio Tonetti, chair of the University of Connecticut’s Division of Periodontology, conducted a study looking into whether reversing the production of bacteria and toxins in the mouth would benefit patients who had atherosclerosis, the results were encouraging. He reported in the New England Journal of Medicine last year that patients who underwent an intensive, six-month program of treatment for gum disease emerged not only with healthier gums but also with improved endothelial function – that is, better function of the lining of the blood vessels. No, this does not necessarily mean better vascular function overall, but the experts say that these findings merit further study.

As does a possible link between gum infections and preterm labor. Nearly 13 percent of births in the United States are considered preterm (occurring before 37 weeks of gestation), and of these, almost half occur without explanation. This has prompted researchers to look at the role of gum disease.

Observational studies show rates of preterm birth are higher for women with severe gum disease than those with milder or no such disease. A recent review in the journal American Family Physician noted that studies of nearly 15,000 women in “identified 24 studies demonstrating a positive relationship between periodontitis and preterm birth, low birth weight, or both.”

Gum disease may also be implicated in a “small, but significant” increase in overall cancer risk for men, according to a recent study in The Lancet Oncology. The authors linked gum disease to a higher chance of lung, kidney, pancreatic and blood cancers. A similar pattern is emerging for kidney disease and Alzheimer’s. But as with heart disease and preterm labor, the question of what causes what has not been definitely answered.

In diabetes, however, the body-mouth connection is clear-cut. Diabetics who have uncontrolled gum disease, Cram said, “have a much harder time (than other diabetics) controlling their blood sugar levels.” The reverse, she noted, is also true: People with uncontrolled diabetes are about “three to four times at greater risk of developing periodontal disease.” The cycle is very hard to break.

You would think that physicians would be telling their diabetic patients to make regular dental visits to head off gum disease and that dentists would be advising patients who develop persistent gum disease to be tested for diabetes. But neither group of practitioners has been especially good at making the connection.

Similarly, despite growing evidence of a link between preterm labor and gum disease, only 22 to 34 percent of U.S. women consult a dentist during pregnancy, according to a 2001 report in the Journal of the American Dental Association; other studies also show lower use of dental services during pregnancy. Among women who develop mouth problems during pregnancy, only 50 percent seek help; many of the rest worry that mouth treatment may be harmful to their babies.

Experts such as Caswell A. Evans, director of the National Oral Health Initiative, think it is past time for patients to reconsider how they think about the dentist vis-a-vis the doctor. We minimize many mouth ailments, he says, shrugging off “blood on (our) toothbrush.” And dental patients need to get past thinking of their dentist primarily as a cosmetic practitioner – a whitener and straightener of teeth – or a “fireman” to be called only when there’s extreme tooth pain.

Regular visits to a dentist can make the mouth an early warning system for a variety of problems. Sores or fungus in the mouth, for example, are often the very first indications of infection by HIV, the virus that causes AIDS, or of cancer. Osteoporosis, a disease of the bones, could show up in a routine dental X-ray before you notice its impact on your hips or spine.

For their part, dentists and doctors are beginning to realize they might help their patients by joining forces.

“There’s a desperate need for more collaboration between the two specialties,” emphasizes Alan Douglass, an associate professor of family medicine at the University of Connecticut School of Medicine. That’s why Douglass and his colleagues created a national oral health curriculum aimed at doctors, “Smiles for Life.”

Doctors, Douglass says, “need to serve as an entry point into the dental-care system.”

Meanwhile, Evans is urging his fellow dentists to consider the whole person and be “cognizant of their medical needs” as well as their dental ones.

One thing both groups agree on is the power of prevention, which means brushing, flossing and having regular professional cleaning.

Doctors can also help identify at-risk patients. The good news is that if you catch gum disease in its early stages, Cram says, “you can reverse it” with procedures such as scaling and root cleaning.

So, take care of your mouth. Your heart, your brain and your kidneys may thank you for it. As Evans puts it: “Oral health is not an out-of-body experience.”