Having trouble convincing your patients to maintain consistent oral hygiene habits between visits? If you need extra ammunition in the fight to keep everyone brushing their teeth, here’s one: new evidence suggests that it might help reduce your risk of dementia. 

A female dentist stands next to an elderly patient sitting in a dental chair. The two of them are looking at x-ray images of teeth.

New Dementia Connections

Scientists have consistently discovered a connection between poor oral health and cognitive decline. According to the U.S. Centers for Disease Control and Prevention’s 2014 data, over 5 million American adults aged 65 and above live with dementia, with Alzheimer’s disease being the most common form. This condition impairs one’s ability to remember, think, and make decisions. 

Numerous studies have indicated that individuals with inadequate oral health are more susceptible to developing dementia. However, the exact nature of this link has remained unclear. In a recent comprehensive review published in Aging Research Reviews, researchers from Taiwan’s National Yang-Ming Chiao Tung University analyzed data from 28 systemic reviews to identify the factors contributing to these associations and how they could inform future evidence-based clinical advice. 

Gum Disease and Brain Health

Professor Chia-Shu Lin, lead author of the study, explains the primary focus of existing review: “Most systematic reviews consistently concluded on the role of oral microbiome, the ‘ecosystem’ of oral micro-organisms, in dementia.”  

Gum disease, characterized by chronic inflammation in the oral cavity, is a serious infection. Due to its proximity to the brain, scientists suspect that this inflammation may negatively impact the brain. Previous studies have found that gum disease and tooth loss are associated with shrinkage in the hippocampus, the brain region responsible for learning and memory. 

“The evidence is concluded from both animal and human studies,” Lin says. “The association between periodontitis, a major gum disease in adults, and dementia was also consistently reported by previous reviews.” 

Finding Links in Alzheimer’s Studies

Studies have also indicated that a common microbial culprit of gum disease, Porphyromonas gingivalis, can be found in the brains of individuals who died from Alzheimer’s. Professor Satoshi Yamaguchi from Tohoku University in Japan says these microbes may be able to invade the brain and damage that nerve tissue. 

While Lin’s review demonstrated a consistent association between dementia risk and oral health, there are additional factors to consider. Lin says, “With dementia, patients deteriorate in self-caring ability. For example, patients with Alzheimer’s disease find it challenging to brush their teeth, exacerbating oral health and cognitive function. Such a deterioration in self-caring behavior may induce a ‘vicious cycle’ that worsens one’s overall health.” 

Also, most studies included in these reviews are observational, depicting statistical correlations between oral health and cognition without clarifying cause-effect relationships. More studies will need to be done to determine causality. Until then, we can only make inferences based on careful interpretation of available data. 

An arm in a lab coat uses a pen to point to an x-ray image of a brain.

Can Dementia Be Prevented?

Lin says that, despite the consistent association revealed in the review studies, preventing dementia is not as simple as brushing your teeth. As we know, degenerative conditions like dementia are multifaceted, and not yet fully understood. Nevertheless, this connection between dental health and the health of your brain is significant and, thus far, overlooked. 

To learn more about the science behind oral health, ways to explain to patients how to recognize a serious problem, and the ways their teeth connect to their bodies’ overall well-being, visit Dental U. Benco’s education resource center where you can find articles, podcasts, white papers, and webinars designed to put all the information you need at your fingertips.