FORT MYERS, Fla. - Whitening done at a salon, spa, or even mall kiosk can be several hundred dollars cheaper than in the dentist's chair but, dental professionals say it's dangerous.

"She came to our office, her gums were reddish, purplish, she was very upset, and said she would never have it done again," described Dr. Allan Rembos, a cosmetic dentist with offices in Fort Myers, Naples and Sanibel.

Dr. Rembos treated a patient who had a bad experience with whitening. The patient had gone to a whitening kiosk at a shopping mall, and when she came to Dr. Rembos her gums were in severe pain.

"We had to backtrack a little bit, get her teeth cleaned back up and calm the gums, get her back to where she should have been prior to having that done," said Dr. Rembos, whose been practicing dentistry for 25 years.

In the last few years, he says he's seen an alarming trend: whitening salons opening inside malls, tanning and beauty salons, and even mobile RVs.

"The problem with mall whiteners has been the fact that they have absolutely no professional ability to diagnose," said Dr. Rembos.

The companies do not normally employ dental professionals, but use peroxide-based gels in combination with exposure to high intensity lights.

The companies have become so popular, the American Dental Association has taken an official policy on them.

"We feel that anyone who is not a dentist or in a dental office is practicing dentistry illegally in a way by pretending to be an educated dental professional," said Dr. Leslie Seldin, the ADA's consumer adviser and national spokesperson.

Whitening salons are legal in the state of Florida as long as they are only selling the product and not actually touching the customer's mouth in any way.

Dentistry boards in six states and the District of Columbia have taken steps to regulate the salons, by enforcing the sale only policy.

Dr. Rembos said it may be legal, but he doesn't think it's right.

"Can you imagine going to your dentist's and me handing you the hand piece and saying okay now go work on this tooth."

Dentists say they're concerned about the problems that can occur if whitening is not done properly, or if it's done before the patient has had an exam or cleaning at a dental office.

"A lot of problems can occur, damage to the teeth, to the gums, to the pulp the nerve inside the tooth, all of it," said Dr. Rembos.

But business owners, and spokespeople for the cosmetic whitening industry feel differently.

"Our argument is if you haven't gone to the dentist, the same will happen to you as Crest White Strips," said George Nelson, who said over the phone he was the owner of White Science LLC.

Nelson said his company is one of the nation's largest suppliers of cosmetic whitening products in the United States.

"Dentists are protecting their own turf," said Nelson, "(our products) are in the biggest salons,spas and shopping malls in America, if these things were really dangerous they would be shut down for pure business reasons."

Call For Action armed two producers with hidden cameras to go inside local whitening salons to find out how the procedure is done. Our cameras weren't able to catch a customer at the salons during several stakeouts.

When a producer posed as a potential customer, the employees at the salons were very upfront about the law.

"He said he could not put it in your mouth whatsoever, because he's not a dentist and it would be illegal to do so," said Maggie, a WINK News employee.

At two salons, Maggie was told similar information about how the process would work: the customer puts trays filled with whitening gel in their own mouth and then the employee places the light over their mouth.

The first salon did nothing to protect the patient's gums. The second salon handed out a vitamin E solution on a cotton swab.

"She said it helps with the sensitivity," said Maggie.

Protection of the gums is a big part of a dental office procedure.

Dr. Rembos showed us a typical whitening process in his office.

"The difference between what's done at your dentist's office and what's done at the mall is like night and day," said Dr. Rembos.

Rembos' assistant spent around twenty minutes covering the gum areas in the mouth with a hard material. When she was finished, we could not see any pink inside the patient's mouth: the teeth were completely isolated.

After the isolation process, Dr. Rembos inspects the patient's mouth then applies the gel and the light.

"I don't think that's the procedure being done in the mall, I know that it's not," said Rembos.