“I put their power right up there with the NRA,” Malaby said. “Dentists do everything they can to protect their interests — and they have money.”

As the cost of dental care rises beyond the reach of millions of Americans, the dental lobby is coming under increasing scrutiny. Critics say the ADA has worked to scuttle competition that could improve access to dental care in underserved areas and make routine checkups and fillings more affordable.

The Federal Trade Commission has battled dentists in state after state over anti-competitive conduct. In 2007, the FTC successfully settled a complaint over a South Carolina dental board requirement that dentists examine children in school clinics before hygienists can clean their teeth, adding greatly to the cost. In 2015, the FTC won a Supreme Court ruling against the North Carolina dental board, which tried to block teeth-whitening businesses from operating in malls.