Dental Utilization Stratified by the Purpose of Visit: A Population-Based Study in Japan

BACKGROUND: This study aimed to provide a stratified description of dental visit utilisation by Japanese residents based on patient age, sex, prefecture, and the purpose of the visits. METHODS: This cross-sectional study used the National Database of Health Insurance Claims of Japan to identify participants visiting dental clinics in Japan (April 2018–March 2019). Dental care utilisation by populations stratified by age, sex, and prefecture was assessed. We estimated the slope index of inequality (SII) and relative index of inequality (RII) to evaluate regional differences based on regional income and education. RESULTS: Amongst the Japanese population, 18.6% utilised preventive dental care visits; 59,709,084 participants visited dental clinics, with children aged 5 to 9 years having the highest proportion. SII and RII were higher for preventive dental visits than those for treatments in all settings. The largest regional differences for preventive care were observed in SII of children aged 5 to 9 years and in RII of men in their 30s and women aged 80 years and older. CONCLUSIONS: This nationwide population-based study revealed that the proportion of people utilising preventive dental care in Japan was low, with regional differences. Preventive care needs to be more easily accessible and available to improve the oral health of residents. The above findings may provide an important basis for improving policies related to dental care for residents.