Periodontal Disease: Causes and Prevention

What Is Periodontal Disease?

If your hands bled when you washed them, you would be concerned. Yet, many people think it's normal if their gums bleed when they brush or floss. In a 1999 study, researchers at the U.S. National Institutes of Health (NIH) found that half of Americans over 30 had bleeding gums.

Swollen and bleeding gums are early signs that your gums are infected with bacteria. If nothing is done, the infection can spread. It can destroy the structures that support your teeth in your jawbone. Eventually, your teeth can become so loose that they have to be extracted.

"Peri" means around, and "odontal" refers to teeth. Periodontal diseases are infections of the structures around the teeth. These include the gums, the cementum that covers the root, the periodontal ligament and the alveolar bone. In the earliest stage of periodontal disease, gingivitis, the infection affects only the gums. In more severe forms of the disease, all of the supporting tissues are involved.

For many years scientists have been trying to figure out what causes periodontal disease. It is now well accepted that bacteria in dental plaque are the major villains. Researchers also are learning more about how an infection in your gums can affect your overall health.

In recent years, gum disease has been linked to other health problems. This is a new and exciting area of research. Many questions remain. Studies have produced varying answers about how much of a connection exists between gum disease and other medical problems. More research is needed.

Researchers are studying possible connections between gum disease and:

Atherosclerosis and heart disease — Gum disease may increase the risk of clogged arteries and heart disease. It also is believed to worsen existing heart disease.
Stroke — Gum disease may increase the risk of the type of stroke that is caused by blocked arteries.
Premature births — A woman who has gum disease during pregnancy may be more likely to deliver her baby too early. The infant may be more likely to be of low birth weight.
Diabetes — Diabetic patients with periodontal disease may have more trouble controlling their blood sugar than diabetic patients with healthy gums.
Respiratory disease — Bacteria involved in gum disease may cause lung infections or worsen existing lung conditions. This is particularly important for elderly adults in institutions such as nursing homes. In this group, bacteria from the mouth may reach the lungs and may cause severe pneumonia.

What Causes Periodontal Disease?

Periodontal disease is caused by bacteria in dental plaque. Plaque is the sticky substance that forms on your teeth soon after you have brushed. In an effort to get rid of the bacteria, the cells of your immune system release substances that inflame and damage the gums, periodontal ligament or alveolar bone. This leads to swollen, bleeding gums, a sign of gingivitis (the earliest stage of periodontal disease). Damage from periodontal disease also can cause teeth to become loose. This is a sign of severe periodontitis (the advanced stage of disease).

You can prevent periodontal disease by practicing good oral hygiene and visiting your dentist regularly. Most people should see the dentist about once every six months. But if you already have gum disease you may need to visit more often.

Daily brushing and flossing, when done correctly, can help to remove most of the plaque from your teeth. Professional cleanings by your dentist or dental hygienist will keep plaque under control in places that are harder for a toothbrush or floss to reach.

If oral hygiene slips or you skip dental visits, plaque builds up on the teeth. Eventually, it spreads below the gum line. The bacteria are protected there because your toothbrush can't reach them. If plaque is not removed, the bacteria will continue to multiply. Your gum inflammation may get worse.

The buildup of plaque below the gumline causes the gums to become inflamed. As the gums swell, they detach from the tooth. This process forms a space, or "pocket," between the tooth and gum. Bacteria can grow rapidly in the pockets. This encourages further plaque buildup.

If left untreated, periodontal disease may destroy the periodontal ligament and the alveolar bone, the structures that support your teeth.

Another reason to remove plaque promptly is that over time it becomes hardened or calcified and turns into calculus. This is commonly called tartar. Even more plaque attaches to calculus because it's a rougher surface than tooth enamel. It's also rougher than cementum, a layer that covers the tooth root. Calculus and plaque build up in layers.

Using a tartar-control toothpaste may help slow the build-up of calculus around your teeth. It can't affect the tartar that already has formed below the gum line, however.

Risks and Prevention

The bacteria in plaque are the main cause of periodontal disease. But several other factors also can contribute. They include other diseases, medicines and oral habits. These factors can increase your risk of gum disease or make it worse once the infection has set in.

Genes
Smoking and tobacco use
Misaligned or crowded teeth, braces or bridgework
Grinding, gritting or clenching of teeth
Stress
Fluctuating hormones
Medicines — SSeveral types of medicines can cause dry mouth, or xerostomia. These medicines include:
Phenytoin (Dilantin and other brand names), used to control seizures
Cyclosporine (Neoral, Sandimmune), used to suppress the immune system in people who have had organ transplants
Nifedipine (Adalat, Cardizem and others) and other calcium channel blockers, used to treat high blood pressure, chest pain (angina) or heart arrhythmias.
Diseases — People with certain diseases have a higher risk of developing periodontal disease.
Poor nutrition