OBJECTIVE To ascertain what proportion of dental hygienists and dentists in Indiana, United States, support the application of fluoride varnish in medical offices, and to determine if support differed by dental provider characteristics, practice characteristics, a limited assessment of knowledge about fluoride, or use of fluoride. METHODS Practicing dental hygienists and dentists in 2005 were asked to fill out a mail questionnaire. Logistic regression models tested the association of independent variables with support for medical providers applying varnish. RESULTS Response rates were 36% (dental hygienists) and 37% (dentists); median year of graduation was 1988 and 1981. Sixty-six percent of respondents were in solo practices, 82% of dentists in general practice, 5% in dental pediatrics, and 13% were other specialists. While 51.2% of dental professionals agreed that medical practices could apply fluoride varnish, 29% responded "none" should be allowed, and 19% were undecided. In the multivariable logistic regression for support of medical practices applying fluoride versus not supporting it, three practice characteristics and two measures of fluoride use were significant. Provider characteristics and a limited assessment about knowledge about fluoride were not significant. CONCLUSIONS Half of dental professionals felt that it was appropriate for medical providers to apply fluoride varnish; pediatric dental professionals were less supportive. A few dental practice characteristics were associated with acceptance of the use of fluoride varnish by medical care providers: targeting messages to dental hygienists and those with practices in mixed rural-urban areas may be a useful approach to garner greater support for this medical/dental partnership.