Poor oral hygiene has been linked to poor mental health in seniors, but the findings just suggest an association and do not establish a cause-and-effect relationship. Researchers reviewed studies on oral health and cognitive decline published between 1993 and 2013.
The researchers found that in some studies a higher number of cavities, the number of teeth a person has, and the presence of gum disease is associated with a higher risk of age-related mental decline or dementia, whereas other studies did not find the same results.
Review author Bei Wu said, “Clinical evidence suggests that the frequency of oral health problems increases significantly in cognitively impaired older people, particularly those with dementia. [But] there is not enough evidence to date to conclude that a causal association exists between cognitive function and oral health.”
The researchers have a few theories regarding the factors that could contribute to the association. For starters, some speculate that “a shared inflammatory pathway is common to both cognitive decline and oral disease,” as explained Dr. Jacqueline Sobota, a dentist at North Shore University Hospital.
Dr. Gayatri Devi, a neurologist and memory loss specialist at Lenox Hill Hospital, added, “Some patients with dementia may develop an apraxia — a condition where one forgets a previously learned task, such as tying shoes, for example, or brushing one’s teeth.”
“Some patients, even if they do not have an apraxia, may just forget to brush their teeth. However, early in the course of dementia, the majority of patients attend to their oral hygiene in the manner they used to prior to developing dementia,” concluded Devi.