Registered dental hygienist Denise Lopez-Rodriguez cleans Laura Breland's teeth at a community health center on March 27, 2012 in Aurora, Colorado.   - 

Have dentists struck gold?

Not in the mouths of their patients, but in of all places, in Medicaid, a program infamous for its low reimbursement rates. 

In a National Bureau of Economic Research reportUniversity of Michigan business professor Tom Buchmueller found that in states that expanded Medicaid under the Affordable Care Act dentists saw about a 7 percent rise in income. And he says some also avoided increased patient wait times.

New income, new patients and no more wait times? How'd they pull that off?

Dentists leaned on their hygienists.

Wait times did increase in states with restrictive so-called scope of practice laws -- where mid-level professionals like hygienists and nurse practitioners -- have less autonomy. 

Incidental Economist contributor Adrianna McIntyre says the study shows the value of relaxing these state laws and giving those mid-level professionals more responsibility.

"I think that we are going to eventually see changes to scope of practice laws. What I don't know is how long that's going to take," she says.

Follow Dan Gorenstein at @dmgorenstein