Periodontal disease, more commonly called gum disease, is inflammation and infection of the tissues and bones surrounding teeth. Also known as gum infection, it is the most common cause of tooth loss, especially among older adults in the United States. Except for those who may be genetically more susceptible to periodontal problems, the disease can be prevented through regular brushing and flossing (oral hygiene).

Periodontal means “surrounding the tooth.” Periodontal tissue, membranes and bones help anchor and cradle the teeth into the jaw and keep teeth aligned and secure by fitting snugly against and between each tooth.

Healthy gums (gingiva) act as barriers to keep germs and infection from entering the bloodstream through crevices or periodontal pockets that can develop between the gums and teeth. Diseased or infected gum tissue can become swollen and die. When that happens, the gums pull away from the teeth (receding gums) and open a pathway for bacteria to enter blood vessels.

The presence of bacteria in the tissues (mucous membranes) of the mouth is normal. Those bacteria, along with food particles and acids in the mouth, interact and cause the growth of plaque, a sticky film that clings to the surface of teeth. Plaque build-up can sometimes feel like tiny ridges or bumps on the otherwise smooth surface of teeth.

Plaque that remains on the teeth for more than two to three days hardens or calcifies into tartar (calculus). As tartar and plaque build up on teeth and remain lodged next to the gums, the bacteria normally present in the mouth (especially the harmful bacteria responsible for disease) multiply and release toxins that cause the body’s immune system to signal infection in the gums. This leads to swollen (inflamed), red and bleeding gums.

The infection associated with periodontal disease can happen on or around one tooth or several teeth. It occurs most often in areas where it is difficult for toothbrushes and floss to clean, such as the molars, in teeth next to bridges and implants or where there are ill-fitting dentures or misaligned, impacted or crooked teeth. As the immune system fights the infection, a painful pocket of pus (an abscess) can sometimes form in the gums or between teeth.

Left untreated, gum disease can eventually lead to erosion of the periodontal ligaments and alveolar bones that anchor teeth to the jaw. Without that vital periodontal support, the teeth can loosen over time and may have to be pulled.  

According to the National Institutes of Health (NIH), 80 percent of adults in the United States have some form of periodontal disease. The majority have the milder and more common form called gingivitis, which involves inflammation and irritation of the gums and is reversible with treatment. Periodontal pockets of 1 to 3 millimeters (mm) are typical for gingivitis.

According to the American Dental Association (ADA), 20 to 30 percent of adults may have the more severe form of periodontal disease called periodontitis. The infection attacks the gums as well as the underlying bones and tissue supporting the teeth. As the disease progresses, larger pockets begin to form between the teeth and gums as the infected, swollen gum tissue pulls away from teeth and die.

Periodontal disease is sometimes called a "silent threat" to good oral health because it can have no or only minor symptoms. Those who forego regular (twice yearly) dental check-ups are at greater risk of bone or tooth loss from periodontal disease. This is because a dentist can spot the warning signals when examining the teeth and gums and recommend professional and home treatment options.

For those with periodontal disease, some unrelated diseases and conditions can worsen or aggravate the gum and bone inflammation and erosion. Smokers and those with uncontrolled diabetes or HIV/AIDS may experience more severe gum disease and heal less quickly following gum treatment. Pregnancy increases the likelihood of gum inflammation and some studies have shown a link between periodontal disease and premature and low-birth weight babies. Studies have also linked periodontal disease to other systemic conditions, including diabetes, heart disease and respiratory disease.

Periodontal disease can impact patients' lifestyles as well as their overall health. The social stigma attached to tooth loss and persistent bad breath can affect the quality of life of an individual. A 2000 oral health report conducted by the U.S. Surgeon General’s Office found that low self-image and self-esteem and overall social and psychological well being are adversely affected by oral diseases.

Those with advanced periodontal diseases often:

• Smile less or not at all to hide missing, discolored or deformed teeth
  
  
• Have limited food choices because of chewing or biting difficulties
  
  
• Don’t enjoy meals
  
  
• Avoid certain social settings and intimate contact with others