Trends in dental expenditures in Japan with a universal health insurance system

Background: The government of Japan has spent a significant amount on dental healthcare, but it remains unknown how the spending varies across age, type of service, and time. This study describes trends in dental expenditures in Japan. Methods: This descriptive study used two national data sources: Estimates of National Medical Care Expenditure and Survey on Economic Conditions in Health Care. We obtained annual total and average per capita dental expenditures by age in Japan from 1984 to 2020 and estimated the proportions of types of service from 1996 to 2021. All costs were adjusted for the 2020 Consumer Price Index (1 US dollar ≈ 100 yen in 2020). Results: Total dental expenditures increased from 1.96 trillion yen in 1984 to 3.00 trillion yen in 2020. In particular, total and average per capita dental spending for older persons showed a rapid increase (total: from 185 billion yen in 1984 to 1.18 trillion yen in 2020; average per capita: from 15,500 yen in 1984 to 32,800 yen in 2020), contributing to the total amount increase. The crown restoration and prosthesis category amounted to 50.3% of the total expenditure in 1996, and this proportion declined to 32.4% by 2021. In 0–14 years persons, expenses on the crown restoration and prosthesis category decreased while the medical management category (mainly including fees for a management plan for oral diseases or oral functions) increased. In persons aged 65 years or older, expenses on the crown restoration and prosthesis category decreased, with increasing expenses in the medical management and at-home treatment categories. Conclusion: The amount of dental spending in Japan substantially increased from 1.96 trillion yen in 1984 to 3.00 trillion yen in 2020), a 1.53-fold increase. The observed changes in annual dental spending varied across age groups and types of service.