What is Gum Disease?

Gum disease (also called periodontal disease or periodontitis) is an infection of the gums and/or bone that surrounds the tooth and progressively destroys those tissues if left untreated. Generally the disease is painless, and most patients are not aware they have a problem until examined by a dentist. To best explain what gum disease is, it’s helpful to have a basic understanding of a healthy tooth and periodontium.

With a healthy tooth, the root is set in the jawbone with a strong ligament, which keeps the tooth tightly attached to the bone. Gum covers the bone, and like skin, protects it from bacteria that are constantly present in the mouth. The gum connects to the neck of the tooth with a band of fibers, which insert just above the bone into the root. In a healthy situation, the gum edge is higher than the fiber attachment, forming a space (the gingival sulcus) around the tooth, similar to a turtleneck sweater. This sulcus should be 2-3 millimeters in depth.

If bacteria (plaque) are allowed to survive on and colonize the tooth, it causes a chronic inflammatory state. As this infection persists, the body tries to wall it off and the gum tissue may move farther down the tooth (closer to the bone) to avoid the infection. At this time, the sulcus may be deeper than in health (4-5 millimeters in depth) and may bleed when the patient brushes and flosses. This is called “gingivitis” and is usually completely reversible with treatment. Gingivitis is associated with inflammation but irreversible bone loss has not yet occurred.

As time goes on, the inflammation and the gum tissue get closer and closer to the bone and the body responds by dissolving (resorbing) the bone around the tooth. This can result in a much deeper sulcus, called a “pocket” (which is usually over 5 millimeters) that may continue to bleed when the patient brushes and flosses. This bone loss is often not reversible and can lead to loose teeth and tooth loss if not treated. This is called “periodontitis.” It is distinguished from gingivitis by the presence of bone loss.