抄録
This article describes the trends and the current status of dental diseases in Japan, mainly based on the results of the National Survey of Dental Diseases. This survey has been conducted every six years since 1957, which can demonstrate nearly half century’s history of dental diseases of Japanease people. The latest survey in 2005 indicated that tooth retention has improved and dental caries have declined. For instance, the survey in 1975 showed one in 5 (20%) among 55-64 year-old people were edentulous, which has been improved to one in 50 (2%) in the 2005 survey. Additionally, the majority of people over 75 years old were traditionally edentulous, but currently this has been reduced as low as one-third. The improvement of tooth retention might be due to by the increase of dentists. The major factor caries reduction might be recent widespread use of fluoride toothpaste in Japan. The response rate of National Survey of Dental Diseases has declined markedly. For this reason, the importance of other national statistics about dental health has become greater recently.
