Association between presence of 20 or more natural teeth and all-cause, cancer-related, and cardiovascular disease-related mortality: Yamagata (Takahata) prospective observational study

Several studies have surveyed the relationship between the presence of ≥ 20 natural teeth and mortality. However, very few have evaluated this association over a long-term follow-up of more than ten years within a large population in Japan. This study aimed to prospectively confirm the associations between mortality and the presence of ≥ 20 natural teeth within a community-based population in Japan. A prospective observational study including 2208 participants aged ≥ 40 years was conducted in Takahata Town, Japan, between May 2005 and December 2016. All participants answered a self-administered questionnaire to provide their background characteristics, including their number of teeth. The participants were classified into two categories based on their self-reported number of teeth (