Yoo JJ, et al. - Using the Elderly Cohort Database of the National Health Insurance Service, researchers evaluated the correlation between dementia and periodontal disease, dental caries, and tooth loss. They analyzed the risk factors of dementia in older people over 60 years old in this population-based cohort study. Participants were divided into two cohorts based on tooth loss from 2002 to 2011, a tooth extraction and non-extraction cohort. There were 104,903 people in each cohort after matching propensity score and they included a total of 209,806 people in this investigation. Findings revealed that individuals with tooth loss had a higher risk of dementia than those without tooth loss irrespective of sex, age, and number of teeth lost. Dementia incidence increased with an increase in the number of missing teeth and decreased with periodontal treatment. From this perspective, individuals should maintain oral hygiene policies, and those who have difficulty managing their own oral hygiene should facilitate access to oral health care. In contrast, early detection of dementia can be helped by assessing cognitive function in patients with extensive loss of teeth.