What is gum disease?

Causes and Symptoms

Bacterial infection is the most common cause of gum disease. In the early stages of the disease, only the soft tissues—the gums, or gingiva—are affected, but in later stages bacteria also attack the hard tissues underlying the gums.

The bacteria responsible for gum disease accumulate in plaque,
which is a sticky biofilm of bacteria that forms on the teeth above and below the gum line. Plaque that remains on the teeth for more than about seventy-two hours may harden into tartar, which cannot be removed completely except by a professional. Plaque accumulation is usually the result of inadequate tooth brushing and flossing.

Plaque contains many different kinds of bacteria. Bacteria that live below the gum line, where oxygen is low or lacking, are the main culprits in gingivitis, an inflammation of the soft gum tissues. Toxins produced by the bacteria destroy the collagen fibers that make up the connective tissue between the gum and the tooth, causing the gum to loosen and detach from the tooth. The widening and deepening of the space between tooth and gum produces a pocket. Whereas in healthy gums there is a crevice about 1 to 3 millimeters deep between the gum and tooth, in gingivitis there is a pocket up to 4 millimeters deep. The gum becomes movable instead of clinging to the tooth. The gum also swells, is red rather than a healthy pink, and bleeds when brushed or probed. At this early stage, there is little or no pain.

From a gum pocket, bacteria can advance to the bone and to the other hard tissues that support the tooth: the cementum, which covers the roots of the tooth, and the periodontal ligament, which anchors the tooth to the jawbone. Gum disease that has progressed to the bone is referred to as periodontitis. It usually results from a long-term accumulation of plaque and tartar.

In early periodontitis, the crests or peaks of the bone between the teeth have begun to erode. The patient may as yet be unaware of the problem because there is no pain. As the inflammation destroys the fibers of the periodontal ligament and further dissolves the bone, the pocket often deepens to between 4 and 8 millimeters. In advanced stages, most of the bone surrounding the tooth is destroyed and the tooth loosens. Abscesses and pain are common at this point. Advanced periodontitis can cause teeth to fall out or require extraction and is one of the main causes of tooth loss in adults.

In both gingivitis and periodontitis, the damage may be localized. Furthermore, the disease does not progress at a uniform rate but instead advances episodically, with periods of remission. Most adults have had gingivitis at one time or another, but some individuals are especially susceptible, including those who smoke, have certain medical conditions, or take particular medications.

Treatment and Therapy

Gum disease is treatable. To diagnose the disease, the dentist may use x-rays to determine the extent of bone loss and a dental probe to measure the depth of pockets. The dentist removes plaque and tartar by scaling the surfaces of the teeth and planing the surfaces of the roots. An ultrasonic scaler, which cleans the teeth with high-frequency vibrations, may also be used. Once the bacterial biofilm has been removed, the gums are able to heal and reattach to the teeth, thereby shrinking the pockets.

Oral antibiotics are also useful in fighting periodontitis, though they are not effective for gingivitis. In addition, antibiotics inserted directly into deep gum pockets can deliver high concentrations directly to the infected area.

Surgery is performed on some patients, either by a general dentist or by a periodontist. Under local anesthesia, flaps of gum tissue are cut away from the underlying bone, thus allowing better access for scraping and cleaning the tooth roots and for correcting bone defects caused by the infection. Some of the infected gum tissue is also removed, and the remaining gum is sutured back in place.

An important tool in the fight against gum disease is good oral hygiene. Individuals should brush twice a day and use dental floss daily to remove plaque. In addition to toothpastes, effective cleaning agents include baking soda, peroxide, and some mouth rinses. A regular schedule of teeth cleaning by a dental professional is also essential. Depending on how fast a patient accumulates tartar, professional cleaning may be required every three to six months.

Perspective and Prospects

Humans have attempted to clean their teeth since prehistoric times. Early humans fashioned implements out of twigs and bone splinters to remove bits of food trapped between their teeth. Later, the toothpick became the main tooth-cleaning tool. The Chinese are credited with inventing the toothbrush around 1000 CE. It was not until the late 1930s, however, that an inexpensive toothbrush became available.

Research on the causes, prevention, and treatment of gum disease is being conducted at dental schools and at the National Institute of Dental and Cranio-Facial Research. Research areas include attempts to regenerate periodontal tissues. Bone grafting can help restore lost bone, and guided tissue regeneration may help re-create periodontal ligament.

Bibliography

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Wood, Debra. "Gingivitis (Gum Disease)." Health Library, September 12, 2012.