Good Oral Health Linked to Better Brain Health

Taking care of your teeth may lead to better brain health, according to a recent study that showed a link between poor oral health and brain shrinkage in the hippocampus, a brain structure that plays a major role in memory and learning.

The study, published in Neurology, indicates that oral health may contribute to risk of dementia and Alzheimer’s disease, conditions closely associated with the hippocampus. 

Conducted  by researchers from Tohoku University in Sendai, Japan, the investigation aimed to determine whether oral health was related to brain disease. 

"Tooth loss and gum disease, which is inflammation of the tissue around the teeth that can cause shrinkage of the gums and loosening of the teeth, are very common, so evaluating a potential link with dementia is incredibly important," said study author Satoshi Yamaguchi, PhD, DDS, of Tohoku University. "Our study found that these conditions may play a role in the health of the brain area that controls thinking and memory, giving people another reason to take better care of their teeth."

Included in the study were 172 people with an average age of 67, all of whom reported no memory problems at the beginning of the study. Each participant took memory and dental tests before and after the four-year trial period. Researchers analyzed the participants’ number of teeth and checked for gum disease through a measurement of the gum tissue known as periodontal probing depth. Participants also underwnt brains brain scans to measure the volume of their hippocampus.

Researchers found that number of teeth and amount of gum disease were linked to changes in the left hippocampus of the brain. For those with mild gum disease, the study showed that having fewer teeth was associated with a faster rate of brain shrinkage in the left hippocampus. Those with severe gum disease with more teeth showed a faster rate of brain shrinkage in the same area.

According to the study's authors, these results indicate an association between oral and brain health. However, they noted that the findings do not prove that gum disease or tooth loss cause Alzheimer's.

"These results highlight the importance of preserving the health of the teeth and not just retaining the teeth," Yamaguchi said. "The findings suggest that retaining teeth with severe gum disease is associated with brain atrophy. Controlling the progression of gum disease through regular dental visits is crucial, and teeth with severe gum disease may need to be extracted and replaced with appropriate prosthetic devices."