Many people lose teeth as they get older, and many people lose some memory capacity as they get older. Could these two things be related?  To find out, researchers are exploring the possible links between oral health and memory loss.

Richard Crout researches gum disease at the West Virginia University School of Dentistry. He says in recent years, oral health researchers have found that tooth and gum disease have links to many other health problems - from heart disease to premature birth and pregnancy complications. Now they think there might be links to memory loss.

Crout says many dentists see older patients with memory loss who come into their offices with teeth that are a mess. Often that's because these patients have forgotten to do the basics of self care.

"Now we know that if somebody has dementia or they are demented or they have Alzheimer's, that they are going [to] potentially forget to brush or floss their teeth," he says. "That would not be new, but what surprised us was the linkage between mild to moderate memory loss and oral disease."

Crout and his students examined data from the NHANES [National Health and Nutrition Examination Survey], a national survey of Americans, which asked them about their health. Subjects in the study also had dental exams.  And the data showed that people who reported tooth and gum disease had lower scores on tests that measured memory and cognition.  

One hypothesis that would link oral disease and memory loss relies on new evidence about how tissue inflammation affects the brain.

"Our hypothesis is that there are inflammatory byproducts that come from the infection that exists in our mouths, particularly with the more advanced form of gum disease," Crout says. "And these byproducts can then travel to areas of the brain that have been noted to be an area of concern for those patients with memory loss."

But he says it can be hard to determine which problem comes first - memory loss or diseases in the mouth.  To tease out that relationship, Crout says he will need to study patients over a long period of time, watching for both periodontal disease and memory loss. He recently received a large grant from the U.S. National Institutes of Health to pursue this line of investigation.  

"For certain sets of patients, we would have their baseline inflammatory markers in the blood. In other words, we would know the levels of these different levels of toxins," Crout says.

"We then have their dental examinations and their periodontal examinations done, and we then have their memory tests done. So what we would do is that we would then perform an intervention."

An intervention could be, for example, to give some patients an electric toothbrush that helps them care for their mouths better, while other patients just get a regular toothbrush. Then Crout would watch over time and measure what is happening to these patients' ability to remember.  

He says it might take many years before he gets an answer to his hypothesis. 

Abstract of earlier study by Richard Crout