Tooth loss may predict the development of dementia late in life, according to research published in the October issue of The Journal of the American Dental Association.

Researchers from the University of Kentucky College of Medicine and College of Dentistry in Lexington, studied data from 144 participants in a study of aging and Alzheimer’s disease among Catholic sisters of the School Sisters of Notre Dame.

The researchers used dental records and results of annual cognitive examinations to study participants from the order’s Milwaukee province who were between the ages of 75- and 98-years-old.

“Of the participants who did not have dementia at the first examination, those with few teeth (zero to nine) had an increased risk of developing dementia during the study compared with those who had 10 or more teeth,” the authors wrote in their study.

Researchers said there could be several reasons for the association between tooth loss and dementia. For one, not only periodontal disease, but also early-life nutritional deficiencies, infections or chronic diseases may result simultaneously in tooth loss and damage to the brain, they said.

“It is not clear from our findings whether the association is causal or casual,” they wrote, urging further study.