Tooth Loss Linked to Memory Problems, Dementia

Written by Deborah Mitchell
January 10, 2010
The full article can be accessed here


Is there a relationship between losing your teeth and losing your memory? The results of one new study suggest that people who have fewer of their own teeth are at an increased risk of memory problems or early stage Alzheimer’s disease. Yet another study found no association between tooth loss and memory loss.

Poor oral health may impact memory

Oral health and overall health are intimately connected. Research shows that several types of cardiovascular disease, including heart disease, stroke, and atherosclerosis, may be linked to periodontal disease. Gum disease has been linked to premature birth, and having diabetes increases the risk of tooth loss, cavities, and gum disease.

In a study published in Behavioral and Brain Functions, more than 4,200 Japanese adults age 65 or older underwent a thorough dental examination and psychological evaluation. The investigators found that individuals who had fewer of their own teeth were at increased risk of memory loss or early stage Alzheimer’s disease.

The study’s lead investigator, Dr. Nozomi Okamoto of Nara Medical University in Japan, noted that study participants who had symptoms of memory loss reported they rarely or never went to the dentist, which could explain the study’s findings. He pointed out, however, that other factors could be involved in a link between tooth loss and memory problems.

Okamoto explained that “infections in the gums that can lead to tooth loss may release inflammatory substances, which in turn will enhance the brain inflammation that cause neuronal death and hasten memory loss.” Gum disease is the main cause of tooth loss in adults.

In another recent study, published in the Journal of the American Geriatric Society, investigators at the University of North Carolina School of Dentistry studied tooth loss patterns in older adults who had dementia. Of 491 older adults who visited the study clinic as new patients during the study period, 119 were identified as having dementia, Alzheimer’s disease, or chronic brain syndrome.

Participants with dementia came to the clinic with an average of 18 teeth while those without dementia had an average of 20. Tooth loss did not differ significantly between the two groups: at the 12-month follow-up, 11 percent of subjects in each group had lost teeth. Over five years, the average number of teeth lost was 1.21 for participants with dementia and 1.01 for those without dementia.

Although one of these studies suggests tooth loss is associated with dementia while the other one does not, poor oral health is known to be associated with serious health problems. The nature of the relationship between tooth loss, oral health, and dementia warrants further investigation.


Chen X et al. Journal of the American Geriatric Society 2010 Dec; 58(12): 2300-7
Okamoto N et al. Behavioral & Brain Functions 2010 Dec 31; 6(1): 77