Did the American Dental Association threaten to limit dental care in Maine if state lawmakers ban mercury fillings?

The Chicago-based group says it never made such a threat. But two advocacy groups claim otherwise and have filed an antitrust petition with the Federal Trade Commission and the Maine attorney general.

The groups — Consumers for Dental Choice and The Maine People’s Alliance — Tuesday asked Attorney General Stephen Rowe to investigate and even block the alleged boycott.

“The ADA is strong-arming the people and the children of Maine,” claimed Charles Brown, a Consumers for Dental Choice lawyer. “The ADA is trying to face down the Legislature.”

The debate comes as lawmakers weigh two bills — LD 1327 and LD 1338 — that would phase out the use of mercury, or amalgam, fillings.

Opponents say the fillings are detrimental to human health and the environment.

They ask why Maine allows mercury in the mouths of children when the state has been a leader in trying to remove the toxin from the natural environment.

But the medical community, in general, says mercury fillings are perfectly safe. The dental profession uses mercury to bind tin, zinc, silver and copper in amalgam fillings. Many dentists believe mercury is harmless when used with other metals.

At a legislative hearing last week on the mercury bills, representatives from the state Department of Environmental Protection and the Bureau of Health, among others, testified against the bills, sponsored by Sens. John Martin, D-Eagle Lake, and Dennis Damon, D-Trenton.

Opponents said alternatives for mercury fillings are much more expensive and requiring their use could keep some Mainers from receiving care.

The ADA submitted written testimony against the legislation.

If the bills pass, the ADA said “the result will be treatment delayed, treatment denied, and treatment never being sought.”

To the advocacy groups, that sentence sounded like a threat. They claimed it announced the ADA’s intent “to withdraw dental services” from Maine if the mercury bills pass.

It’s unclear just how such a boycott would take place, but the groups said the ADA has “monopoly market power” and “plays a major role in recommending where dentists should locate their practices.”

The ADA on Tuesday called the claim baseless and false.

So did Francis Miliano, executive director of the Maine Dental Association, based in Manchester. The state’s dentists would not deny services to Mainers, Miliano said.

A Natural Resources Committee work session on the bills is scheduled for 1 p.m. Thursday in Room 214 of the Cross Office Building.