Income-related disparities in dental outpatient service utilization among Korean adults: a study using the 2019–2023 Korea Health Panel

Objectives: This study aimed to investigate disparities in dental outpatient service utilization according to income level among adults using the 2019–2023 Korea Health Panel data. Methods: This study included 54,446 adults aged 20 years or older who participated in the Korea Health Panel from 2019 to 2023. Income level was classified into five income quintiles (Q1–Q5). Complex samples logistic regression analysis was performed to examine the association between income level and dental outpatient service utilization. Results: After adjusting for sex, age, marital status, education level, health insurance type, and chronic disease status, Q5 showed significantly higher odds of dental outpatient service utilization than Q1 in every year from 2019 to 2023. The adjusted odds ratios for Q5 versus Q1 were 1.81 in 2019, 1.75 in 2020, 1.50 in 2021, 1.47 in 2022, and 1.39 in 2023 (all p<0.05). Adults in Q3 also had significantly higher odds of dental outpatient service utilization than those in Q1 in most years after 2020. Conclusions: Disparities in dental outpatient service utilization according to income level persisted among adults throughout 2019–2023. These findings suggest that socioeconomic inequalities in dental care utilization remain and highlight the need for policy support to improve equity in dental care utilization and enhance access to dental care for low-income populations.