Incidence of edentulism among older adults using the Korean National Health Insurance Service database, 2013-2018

OBJECTIVES: Population aging is rapidly accelerating worldwide. Oral diseases related to aging are also on the rise. This study examined trends in the incidence of edentulism among the older Korean population using data from the Korean National Health Insurance Service (KNHIS).METHODS: Data on older adults, aged >= 75 years of age, were obtained from the KNHIS for the period 2013-2018. Edentulism was defined as a treatment history of complete dentures in the KNHIS database. The exclusion criteria consisted of both disease codes and treatment codes related to conservative dental treatment, including periodontal and extraction treatment afterward. Crude incidence rates (CIRs) and age-standardized incidence rates (AIRs) with 95% confidence intervals were calculated and reported per 100,000 person-years by the direct method. Trends were tested by Cochrane Armitage models.RESULTS: Statistically significant increasing trends in both CIRs and AIRs were found among the older Korean population reg-istered in the KNHIS (CIRs, 707.92 to 895.92; AIRs, 705.11 to 889.68; p < 0.01). The incidence tended to increase in both gen-ders (p < 0.01). Both CIRs and AIRs in specific regions also showed slight but significant annual increases except for Jeju Island (p < 0.01 or < 0.05). The incidence showed increasing trends (p < 0.01) in all income quintiles apart from the highest quintile. The edentulism incidence was highest in the lowest income group (the first quintile).CONCLUSIONS: Our data showed that the incidence of edentulism among the elderly showed an increasing trend from 2013 to 2018. This result provides a basis for future epidemiological studies on the incidence of edentulism in the older Korean pop-ulation.