Two recent studies demonstrate that people with periodontal disease may be at greater risk for Alzheimer's disease.
In 2013, the Journal of Alzheimer's Disease published findings of a study that provides another indication of how oral bacteria can enter the bloodstream and contribute to Alzheimer's disease. Porphyromonas gingivalis, bacteria linked to gum disease, were found in four of 10 samples of brain tissue of Alzheimer's patients. No signs of the bacterium were found in the brains of 10 people of similar age without dementia. Over time, the chemicals produced by the bacteria could build up and contribute to the development of Alzheimer's.
These findings support previous research published in 2011 in the Journal of Neuroinflammation in which researchers found six periodontal pathogenic spirochetes in the brains of people with Alzheimer's disease. According to author Judith Miklossy, infection occurs years or decades before the manifestation of dementia. The spirochetes form plaque, tangle, and curly fibre-like lesions, and their number progressively increases in patients with Alzheimer's. Spirochetes escape destruction by the host immune response and establish chronic infection and sustained inflammation. Miklossy states, "The pathological process is thought to begin long before the diagnosis of dementia is made, therefore an appropriate targeted treatment should start early in order to prevent dementia."