Objective To examine geographic access to dental providers for the general population and children with public insurance in Missouri and Wisconsin. Methods Using a newly constructed dentist office database from the American Dental Association master file and other sources, we use the two-step floating area catchment area method to calculate population to provider ratios at the census block group level. These ratios are used to determine potential geographic dentist shortage areas. We utilize street network data to estimate travel times and catchment areas between population centers and dental offices. This methodology accounts for the actual spatial distribution of dental providers and potential dental patients. Results Within and across Missouri and Wisconsin, there is some variation in geographic access to dental offices for the general population and publicly insured children. More than 90 percent of publicly insured children have access to dental providers within 30 minutes. Among the states examined, Missouri has more geographic disparities to dental care. Conclusion The Health Resources and Services Administration, which designates dental health professional shortage areas, relies on administrative boundaries to calculate population to dental provider ratios. These boundaries may not reflect actual or “real-time” dental care markets. The methods employed in this paper may give policymakers a template to better determine geographic dentist shortage areas.