The mouth is a unique bio-environment for bacteria and other microorganisms. The oral cavity must always be in microbial and immune homeostasis (balance).. Hundreds of types of bacteria need to be properly balanced to protect the mouth from infection or severe gum disease can result from microbial imbalances or “dysbiosis”.
Many microorganisms in the mouth attach to the teeth. The accumulation of microbes on the surface of teeth is called a “biofilm”, which may eventually calcify into a matrix of hard material called “plaque”.
If not removed, biofilms can lead to inflammation of the gums; a first step in the development of dental caries and “gingivitis”. This mild form of gum disease results in swollen and red gums that may exude pus and bleed easily upon brushing. If left untreated, gingivitis may escalate to periodontitis. In periodontitis, pockets of microbes form and the infection spreads and grows below the gum line, damaging bone, and loosening teeth.
Periodontal-causing pathogens in the mouth trigger defense mechanisms resulting in defensive inflammation. However, when inflammation is not controlled, bone and connective tissues are damaged; the gums pull away from the teeth and leave them in danger of falling out.
When dysbiosis occurs, pathogenic periodontal bacterial communities may overpopulate the mouth. The bacteria are able to circumvent immune cell attacks. As the number of bacteria increase, they stimulate more inflammatory responses leading to bone loss and worsening periodontitis.
As might be expected, treating periodontitis decreases the biomarkers of inflammation throughout the body.
Atherosclerosis and cardiovascular disease
Inappropriate levels of inflammation in the mouth can lead to inflammation throughout the body. It is therefore not surprising that periodontal disease increases the risk of having other inflammatory conditions such as atherosclerosis and cardiovascular disease. Indeed, individuals with atherosclerosis and periodontitis share genes that appear to stimulate similar inflammatory pathways.
Alzheimer’s Disease (AD).
Amyloid plaque accumulation in the brain is a major feature of Alzheimer’s disease (AD); heightened levels of amyloid have been associated with greater risk of periodontal disease. Even in seemingly healthy elderly individuals, those with periodontal disease have more amyloid in their brains than those without oral disease.
Individuals with strong immune responses to periodontal pathogens are at greater risk of developing Alzheimer’s than people who have more limited responses. This has led investigators to suggest that inflammation-associated periodontal disease may be a contributor to Alzheimer’s.
A major function of the immune system is to keep the numerous bacterial communities on and throughout the body in check. To accomplish this, the body maintains immune homeostasis, exquisitely balanced inflammatory responses.
One might predict that maintaining good oral health would decrease one’s risk of inflammatory diseases including diseases such as cardiovascular and Alzheimer’s Disease.