Project Summary Despite significant overall progress in improving access to dental care among children in the United States in recent decades, substantial disparities in oral health have persisted among publicly insured children. Although Medicaid provides comprehensive dental coverage for all enrolled children, dental benefits for adults are optional and vary across states and over time. There is evidence that reducing Medicaid adult dental benefits (MADB) lowers access to dental care for low-income adults. However, the impact of changes in MADB on access to dental care for Medicaid-enrolled children is not yet understood. Our long-term goal is to improve access to dental care and oral health outcomes among children in low-income families. To achieve this goal, we will leverage natural experiments in states that changed MADB generosity to examine the spillover effect on dental utilization by Medicaid-enrolled children. We hypothesize that expanding MADB generosity results in increases in both preventive and overall dental utilization and a decline in emergency department visits for dental problems by Medicaid-enrolled children. Using a causal inference approach, we will estimate the longitudinal impact of changes in MADB on children’s dental care utilization through these research aims: Aim 1: Determine the impact of changes in MADB generosity on overall dental utilization by children enrolled in Medicaid using administrative data with a quasi-experimental design. Aim 2: Determine the impact of changes in MADB generosity on preventive dental utilization by children enrolled in Medicaid using administrative data with a quasi-experimental design. Aim 3: Determine the impact of changes in MADB generosity on emergency department (ED) dental utilization by children enrolled in Medicaid using administrative data with a quasi-experimental design. Using administrative data, we will generate monthly estimates of these three measures of utilization and use a causal inference framework to assess the changes in child dental utilization trends before and after the MADB policy changes. We will use interrupted time series approach to account for any secular trends and make robust within state comparisons, and supplement it with a differences in difference approach to provide comparison with control states that did not experience a policy change. Our findings will provide evidence on the spillover effect of MADB generosity on children’s access to dental care. This study will be the first to use administrative data to examine the spillover effect of changing MADB generosity on children’s dental care use. The study aligns with the strategic priorities of NIDCR to understand and work to reduce child oral health disparities.