The Effect of Changing Medicaid Dental Benefits Type on Dental Services Utilization Among the Adult Population

Abstract

Introduction: In 2021, Medicaid invested approximately $18 billion in dental care, yet studies show that access remains limited for many low-income adults. One key strategy that states can use to enhance dental care and reduce disparities among low-income adults is increasing the number of covered dental services. However, few studies have explored the impact of changing the Medicaid dental benefit type on dental services utilization among the low-income adult population at the state-level. Additionally, including the perspectives of Medicaid dental offices in each state would deepen our understanding of Medicaid dental benefits for adults. Objectives: 1) to understand the attitudes of state Medicaid dental offices toward the importance of different types of dental benefits on dental care use among Medicaid beneficiaries, and 2) to explore the impact of changing the Medicaid dental benefit type on adult dental service utilization within each state, considering the year of these changes. Hypothesis: upgrading Medicaid dental benefit type would improve dental services utilization. Approach: This cross-sectional study distributed a survey to all 50 states and the District of Colombia (DC) Medicaid dental offices. Also, we used nationally representative Behavioral Risk Factor Surveillance System (BRFSS) data from 2010 to 2020. Our study population included low-income (household income below 138% FPL) adults aged 18 to 64 years. Statistical analysis: Univariate and bivariate analysis using Fisher's exact test were conducted to analyze the survey data. While difference-in-differences (DID) and regression discontinuity (RD) designs were employed to evaluate the association between Medicaid dental benefit changes and dental care utilization, accounting for individual-level and state-level covariates. Results: The survey, with a 65% response rate, revealed strong agreement on the importance of offering more dental services for Medicaid adult beneficiaries, particularly preventive care, and on the importance of expanding Medicaid eligibility criteria. Moreover, all states expressed a positive attitude toward the importance of including various types of dental services, except for teledentistry, which was less prioritized. Regarding Medicaid dental office satisfaction with the provided dental services, a direct relationship was observed: where an increase in the level of dental benefits offered was associated with higher satisfaction levels reported by Medicaid dental offices. For the BRFSS data analysis, eight states were included based on the year and type of dental benefit change (Emergency to Limited: 1 state; Emergency to Extensive: 4 states; and Limited to Extensive: 3 states). The results of DID and RD analyses suggest that, in general, expanding dental benefit type for Medicaid adult beneficiaries would increase the probability of dental service utilization among low-income adults. However, the magnitude of this increase varied by state. Conclusion and future direction: expanding dental benefits for low-income adults seems to be effective. However, other strategies and state-specific factors should be carefully considered when designing interventions aimed at increasing and sustaining dental service utilization. We recommend gaining a deeper understanding of these state-specific factors, by integrating both quantitative and qualitative approaches, to develop a tailored plan for creating targeted and effective interventions.