The Dental Health Foundation - Dental Health & Prevention

The Mouth As Source of Infection

The human mouth is home to millions of microorganisms, most of them harmless. Under certain conditions, however, some can cause oral infections such as tooth decay or gum disease. Oral bacteria may also enter the bloodstream if normal protective barriers in the mouth are breached. This can happen as a result of dental treatment or even tooth brushing and flossing.

In people with healthy immune systems, the influx of oral bacteria into the bloodstream is harmless. If the immune system is weakened by disease or medical treatments, however, oral bacteria can cause infection in other parts of the body. Infective endocarditis and oral complications of cancer treatments are examples.

• Infective endocarditis results when oral bacteria enter the bloodstream and stick to the lining of diseased heart valves.

Harsh cancer treatments that damage mouth tissues can open the door to debilitating oral infections as well as systemic infections resulting from the spread of oral microorganisms. Besides cancer patients, others at increased risk for general infections caused by oral bacteria include hospitalized patients unable to practice oral hygiene, patients taking medications that reduce saliva flow, and those taking antibiotics that alter the balance of microorganisms in the mouth.


The Mouth as Early Warning System

Problems in the mouth can signal trouble in other parts of the body. AIDS and osteoporosis are examples.

• Mouth lesions and other oral conditions may be the first sign of HIV infection, and are used to determine the stage of infection and to follow its progression to AIDS.


• Studies in post-menopausal women suggest that bone loss in the lower jaw may precede the skeletal bone loss seen in osteoporosis.

Saliva As a Diagnostic Tool

Saliva, like blood and urine, can be used to detect and measure many compounds in the body. Saliva collection has the advantage of being noninvasive.

• Many medications as well as alcohol, nicotine, cocaine, opiates, and other drugs can be detected and measured in saliva. Hormones and environmental toxins can also be measured in saliva.


• Saliva can be used to detect antibodies against viruses such as HIV and hepatitis A and B, as well as antibodies against bacteria like Helicobacter pylori, which causes peptic ulcers.


• Saliva could potentially replace blood testing for diagnosis and monitoring of diseases such as diabetes, Parkinson's disease, alcoholic cirrhosis, and many infectious diseases.

Oral Infections As Risk Factors

Recent studies point to associations between oral infections - primarily gum infections - and diabetes; heart disease; stroke; and preterm, low-weight births. To date, there is not enough evidence to conclude that oral infections cause these serious health problems. Research is under way to determine if the associations are causal or coincidental.

• Gum infections have been called "the sixth complication of diabetes," because people with diabetes are more likely to have periodontal disease. Researchers are exploring a possible two-way connection between the conditions to see if treating gum disease improves diabetic control.


• Recent studies point to an increased risk of heart disease and stroke in people with gum infections; the risk increases with the severity of the oral infection. However, there is not yet enough evidence to establish oral infection as an independent risk factor for heart disease or stroke.


• Some studies have found that mothers of preterm, low birth weight infants tend to have more severe gum disease than mothers of normal birth weight babies. More research is needed to determine if gum infections do indeed contribute to babies being born too soon and too small.

References:

• Centers for Disease Control and Prevention
  National Center for Chronic Disease Prevention and Health Promotion
  http://www.cdc.gov



• National Institute of Dental and Craniofacial Research
  National Institutes of Health
  http://www.nidcr.nih.gov