Bacteria, plaque and tartar build-up on the teeth are the primary causes of periodontal disease. Poor oral hygiene (such as failing to brush at least twice daily and flossing once a day) allows plaque to remain on the teeth and gums. Over time, bacteria release toxins that lead to inflammation, swelling and redness that, if not corrected, may be followed by bone and gum tissue erosion.

A number of factors can increase a person’s risk of developing periodontal disease. These include:

• Smoking. Tobacco use (including smoking and chewing) weakens the immune system, reduces oxygen in the gum tissue and makes it easier for harmful bacteria in the mouth to grow. Smokers also typically do not heal as quickly following periodontal surgery and are more likely to have severe or chronic periodontal conditions.
  
  
• Heredity. The American Academy of Periodontology estimates that 30 percent of adults – even those with good oral hygiene habits – may develop periodontal problems due to their genetic makeup.
  
  
• Diabetes. Swollen, red and sensitive gums are among the symptoms of both type 1 and 2 diabetes, which are disorders in the body’s ability to break down sugar (glucose). Those with diabetes heal less quickly and are vulnerable to numerous infections, including gingivitis and periodontitis.
  
  
• Drug use. Prescription and over-the-counter medications can complicate periodontal disease. Saliva is a cleansing agent that flushes out bacteria. Some medications (e.g., antidepressants, cold medicines, antihistamines) cause saliva to dry up, allowing harmful bacteria to grow in the mouth. Other medications can suppress the immune system, affecting the body’s ability to prevent and fight off periodontal disease (e.g., antiseizure drugs, calcium channel blockers). The American Dental Association has warned that use of the illegal drug methamphetamine (“meth”) causes rapid deterioration of the teeth and gums leading to a condition known as “meth mouth.” Gingivitis develops quickly and is typically followed by tooth loss because of the high acid levels in methamphetamine. Other illegal drugs can contribute to nutritional or immune system problems that can lead to periodontal disease.
  
  
• Hormones. Progesterone and estrogen are hormones that regulate the female reproductive system. They can also enlarge blood vessels in the gums and cause gingivitis. Women who are pre-menstrual (when progesterone levels are highest), pregnant or taking birth control pills (oral contraceptives) often experience gum inflammation and are at greater risk of periodontal disease. Some studies have shown a link between periodontal disease and premature or low-birth weight babies. Post-menopausal women who have bone loss due to lack of the estrogen hormone (osteoporosis) may be at risk for periodontal bone loss as well. Because of this, older women are more likely to lose teeth (called edentulism).
  
  
• Nutrition. A poor diet or malnourishment causes a breakdown in the entire immune system and makes it easier for bacteria in the mouth to multiply. Lack of vitamin C (scurvy) and the nutrient niacin (pellagra) causes bleeding and sore gums.  Also, diets high in sugars (sodas, candy, sweets) create acidity in the mouth and provide fuel for plaque and bacteria to thrive.
  
  
• Viral infections. Certain kinds of herpes viruses, such as those that cause herpes simplex, chicken pox and shingles, may trigger rapid growth of harmful bacteria or help suppress the immune system.
  
  
• Intimacy. Since the bacteria that cause periodontal disease flow through the mucous membranes and saliva in the mouth, sustained intimate contact such as long kisses may transmit the bacteria to others.
  
  
• Stress. Stress makes it more difficult for the immune system to fight all types of infection, including gum infections. The extra force applied to the gums and periodontal bones by clenching and grinding the teeth (bruxism) may worsen any periodontal disease that is present. Bruxism is frequently associated with stress.