Objective To determine whether preventive dental visits are associated with fewer subsequent non-preventive dental visits and lower dental expenditures. Data Sources Indiana Medicaid enrollment and claims data (2015–2018) and the Area Health Resource File. Study design A repeated measures design with individual and year fixed effects examining the relationship between preventive dental visits (PDVs) and non-preventive dental visits (NPVs) and dental expenditures. Data Collection/Extraction Methods Not applicable. Principal findings Of 28,152 adults (108,349 observation-years) meeting inclusion criteria, 36.0% had any dental visit, 27.8% a PDV, and 22.1% a NPV. Compared to no PDV in the prior year, at least one was associated with fewer NPVs (β = −0.13; 95% CI -0.12, −0.11), lower NPV expenditures (β = −$29.12.53; 95% CI -28.07, −21.05), and lower total dental expenditures (−$70.12; 95% -74.92, −65.31), as well as fewer PDVs (β = −0.24; 95% CI -0.26, −0.23). Conclusions Our findings suggest that prior year PDVs are associated with fewer subsequent NPVs and lower dental expenditures among Medicaid-enrolled adults. Thus, from a public insurance program standpoint, supporting preventive dental care use may translate into improved population oral health outcomes and lower dental costs among certain low-income adult populations, but barriers to consistent utilization of PDV prohibit definitive findings.