Good dental care may be linked to better brain health, according to a study published online in the Journal of the American Academy of Neurology “Neurology”.

As found during the investigation, periodontitis and tooth loss are associated with brain shrinkage in the hippocampuswhich plays a role in memory and Alzheimer’s disease.

The research involved 172 people with an average age of 67 years who did not have memory problems.

Participants were subjected to dental examinations and they did memory test at the beginning of the study. They were also submitted to magnetic brain to measure hippocampal volume at the start of the study and after four years.

In each participant the researchers counted the number of teeth and checked for gum disease with measurements of periodontal pocket depth, a measurement of gum tissue.

In healthy teeth the detection depth is from one to three millimeters, mild periodontitis involves a detection depth of three or four millimeters, while severe disease a depth of five or six millimeters and greater bone loss.

According to the research, the number of teeth and the extent of gum disease are associated with changes in the left hippocampus of the brain.

In people with mild periodontitis, having fewer teeth was associated with a faster rate of brain shrinkage in the left hippocampus.

The increase in the rate of brain shrinkage due to the loss of a tooth was equivalent to almost one year of brain aging.

But in individuals, with severe periodontitis of the gums, having more teeth was also associated with a faster rate of brain shrinkage in the same area. The increase in brain shrinkage due to an extra tooth was equivalent to 1.3 years of brain aging.

“These results highlight the importance of maintaining dental health and not just maintaining teeth. Findings suggest that retention of teeth with severe periodontitis is associated with brain atrophy. Monitoring the progression of the disease through regular dental visits is vital and teeth with severe periodontitis may need to be extracted and replaced with appropriate prosthetic devices,” states the study’s author, Satoshi Yamaguki from Tohoku University in Japan.

The researchers clarify, however, that the study does not prove that gum problems or tooth loss cause Alzheimer’s, but only shows an association.