Trends in self-rated poor oral health among all age populations in Korea from 2007 to 2015: monitoring expansion of dental insurance.

Self-rated poor oral health improved among younger people in Korea. The gender gap in the prevalence increased with age and persisted over time. However, income was the strongest determinant of SRPOH among all age groups, regardless of dental insurance expansion. Further studies should aim to draw causal inferences to explore the policy impact of dental insurance benefits.