Climate risk or healthcare investment? Explaining oral health outcomes across European Union member states.

Introduction: Climate change is a major public-health concern, but short-term population-level evidence linking annual climate variability to oral-health outcomes remains limited. This study evaluates within-country associations between temperature, extreme heat days, and three oral-health indicators across EU member states. Methods: A longitudinal ecological panel analysis was conducted for the 27 EU member states from 2016 to 2023. Daily temperatures at each country centroid were obtained from the Open-Meteo Historical Weather API and aggregated to annual mean temperature and days with maximum temperature above 30 °C. Outcomes were GBD 2023 carries and periodontal prevalence and Eurostat unmet dental care. Two-way fixed-effects models used country-clustered finite-sample-corrected standard errors and 999-replication wild-cluster bootstrap Results: Neither mean annual temperature nor extreme heat days were associated with any outcome in the two-way fixed-effects models. Within R-squared values were 0.056 for caries, 0.032 for periodontal disease, and 0.044 for unmet dental care. Wild-cluster bootstrap inference confirmed the absence of associations at the 5% level. Quadratic temperature terms and climate-by-expenditure interactions were also non-significant. Conclusion: Over the eight-year study period, short-term within-country variation in the reconstructed climate indicators was not associated with the examined oral-health outcomes. Nonlinear and expenditure-interaction models were also null. Longer panels, spatially resolved exposure measures, and oral-health-specific financing, coverage, and utilization indicators are needed.