A tale of two public dental benefit programs: Iowa dentist participation in traditional Medicaid versus a Medicaid expansion program

BACKGROUND: In Iowa from 2014 to 2017, there were 2 separate public dental benefit programs for Medicaid-enrolled adults: one for the Medicaid expansion population called the Dental Wellness Plan (DWP), and one for the traditional, non-expansion adult Medicaid population. The programs differed with respect to reimbursement, administration, and benefit structure. This study explored differences in patterns and predictors of dentist participation in the two programs. METHODS: Authors sent a survey to all private practice dentists in Iowa (n = 1301) 2 years after DWP implementation. Descriptive, bivariate, and logistic regression analyses were used to examine patterns and predictors of dentist participation in Medicaid and DWP. RESULTS: Overall rates of dentists’ acceptance of new Medicaid and DWP patients were 45 and 43%, respectively. However, Medicaid participants were much more likely than DWP participants to place limits on patient acceptance. Adjusting for other factors, practice busyness was the only significant predictor of DWP participation, and practice location was the only significant predictor of Medicaid participation. Dentists who were not busy enough were more than twice as likely to participate in DWP compared to others, and dentists in rural areas were almost twice as likely to participate in Medicaid compared to dentists in urban areas. CONCLUSIONS: Dentist participation in Medicaid is an ongoing concern for states aiming to ensure access to dental care for low-income populations. We found distinct participation patterns and predictors between a traditional Medicaid dental program and the DWP, suggesting different motivations for participation between the two programs. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12903-019-0771-z) contains supplementary material, which is available to authorized users.