Regional Disparities in Oral Examination Rates and Outcomes among Infants and Children

Background: Early childhood is a period for establishing lifelong oral health, as dental caries in primary dentition can affect development and predict oral disease.In Korea, oral examinations for infants and children are included in the national health screening program; however, their utilization remains low and regionally uneven.This study aimed to examine regional disparities in oral examination rates and outcomes at the municipal (city/county/district) level.Methods: A retrospective cross-sectional study was conducted using secondary data from the 2023 National Health Screening Statistical Yearbook and regional classification data from Statistics Korea.The study included infants eligible for oral examinations at 18, 30, and 42 months across 251 administrative districts nationwide.Variables included examination rates and outcomes (normal, caution, and need for further examination).Analyses were performed using descriptive statistics, ANOVA or Kruskal-Wallis tests, and Independent t-tests or Mann-Whitney U tests.Results: The national examination rate increased from 53.6% in 2023 to 60.3% in 2024; however, regional disparities persisted.The gap was 10.8 percentage points provincially and 42.5 percentage points municipally.Rural areas showed significantly lower examination rates than urban areas (p＜0.001), and the effect sizes for regional differences were moderate to large in both 2023 (η 2 =0.116) and 2024 (η 2 =0.160).62.9% of municipalities were below the national average.The proportion of children requiring further examination increased markedly after 42 months, from 23.7% to 43.3%, reaching 49.8% in children aged 54∼65 months.Discrepancies between examination rates and outcomes suggest potential selection bias in low-participation regions.Conclusion: Substantial regional inequalities exist in access to oral examinations and outcomes among Korean infants and children.Targeted interventions, including mobile services and community-based education focused on early intervention, are needed.Establishing a municipal-level oral health surveillance system is essential to reduce disparities and inform policy.