by Sarah Childress

One of the credit card companies used to finance expensive medical and dental-care treatments has been ordered to pay millions in compensation for misleading consumers.

Watch Dollars and Dentists , a joint investigation by FRONTLINE and the Center for Public Integrity.

CareCredit, a subsidiary of GE Capital Retail Bank, must refund up to $34.1 million to potentially more than 1 million people, for persuading them to enroll in credit cards they thought were interest free — but actually accrued fees at high rates, according to the Consumer Financial Protection Bureau, which investigated the company after receiving hundreds of complaints.

In Dollars and Dentists, FRONTLINE and the Center for Public Integrity found that CareCredit and other similar companies are part of the central business model used by Aspen Dental and hundreds of other dental and health-care providers. The providers are paid by the credit-card companies in advance for a patient’s entire treatment plan the moment they sign on the dotted line, so care providers have an incentive to encourage consumers to consider more expensive treatments.

CareCredit is one of the largest of these companies, and is offered by about 175,000 dental and health-care providers nationwide as a payment option, according to the Consumer Financial Protection Bureau. Most consumers are given a deferred-interest plan that accrues 26.99 percent annual interest; if the balance isn’t paid in full by the end of a certain period of time, the consumer becomes liable for the interest.

But that’s not what consumers were told, the bureau’s investigation found. Since January 2009, dental and health-care providers misled consumers about the deferred interest, leaving them to believe it was an interest-free card, the bureau said. Even some office staff members charged with explaining the deal admitted they were confused about how it worked. And consumers weren’t always given copies of the CareCredit agreements to review.

The bureau found that CareCredit lacked adequate oversight of the enrollment process and offered little or no training to service providers so they could adequately explain the agreements.

“Medical debt is already a big problem for many Americans,” Richard Cordray, the bureau’s director, told reporters. “Poor credit card transparency should not be making the problem even worse.”

The bureau ordered GE Capital to set up a $34.1 million fund and notify 1.2 million consumers that they may file for reimbursement. They must also enhance the disclosures for consumers, including requiring a CareCredit representative to complete the process for transactions of more than $1,000, and conduct training for service providers who offer their product. The company has cooperated with the bureau.

Dori Abel, a spokeswoman for GE Capital, told The New York Times that the company had “consistently” seen high customer satisfaction with the CareCredit card.

Bob Fontana, Aspen’s chief executive, told FRONTLINE in 2012 that the third-party financing is an important part of the company’s business model because it helps low-income patients.

“It’s absolutely key to providing the solution for these patients,” he said. “There’s no doubt about it, because again, they’re struggling to get through life. And so it does become an important part of the solution for them.”

Aspen Dental didn’t immediately respond to an email seeking a comment on Wednesday.