Unmet Dental Care Needs among Korean National Health Insurance Beneficiaries Based on Income Inequalities: Results from Five Waves of a Population-Based Panel Study.

This study investigates whether self-employed beneficiaries experience greater difficulties in accessing dental care than insured employees based on their income level. This analysis uses 2011-2015 data from the Korea Health Panel, a population-based and nationally representative sample, covering 7083 participants aged 18 years and older. We measured barriers to dental access based on unmet needs or the inability to receive necessary dental care owing to the past year's economic burdens. The type of health insurance and household income are considered independent variables. We applied multiple panel logistic regressions and two-panel logistic regression models with a fixed-effects approach to analyze the data. Self-employed beneficiaries were 1.16 times (95% confidence interval (CI) = 1.08-1.24) more likely to experience unmet dental needs than were insured employees. Insured employees and self-employed beneficiaries belonging to the lowest income bracket were 1.76 times (95% CI = 1.53-2.03) and 2.33 times (95% CI = 1.89-2.87) more likely to have unmet needs than those in the highest income bracket. Self-employed beneficiaries were 1.31 times (95% CI = 1.21-1.43) more likely to experience unmet dental needs caused by economic burdens than are insured employees. Insured employees of the lowest income quintile were 4.15 times (95% CI = 3.41-5.05) more likely to experience unmet needs caused by economic burdens, while the odds ratio for self-employed beneficiaries was 5.47 (95% CI = 4.05-7.39). Our findings indicate gaps in unmet dental needs between self-employed beneficiaries and insured employees. The government should adopt strategies to reduce unmet needs among marginalized groups and redefine the role of national health insurance.