Special Assignments And Investigations

SACRAMENTO (CBS13) ― Crest's Pro Health mouth rinse is touted as "unbeatable protection against plaque and gingivitis," but some consumers are saying this mouthwash is actually turning their teeth brown.

Commercials for the product promote healthy, beautiful smiles for life, but check online postings from Crest Pro health users, and you'll find dozens of complaints saying those smiles are stained.

"I noticed on the insides of the teeth or tongue, it was just really stained, like yellow and brown it was just gross," said one woman, who wishes to be identified as Debbie.

Debbie said the mouth rinse stained her teeth, and since she happens to be an employee at a local dental office, she does not want to reveal her identity because she believes local offices have a lot on the line.

"You're buying products from these people," Debbie said. "There are just certain agreements that you are locked into and it's hard to stand up and say this product isn't all that it says it's going to be for you."

The mouthwash is now the subject of a class-action lawsuit out of Michigan that claims the Crest Mouth Rinse "causes severe staining and browning of teeth."

Dr. Jonathan Szymanowski, a local periodontist, explained that the key ingredient in Crest Pro health is CPC -- cetylpyridinium chloride -- which has the same properties as one found in the rinses they recommend after oral surgery to keep bacteria levels down.

"This molecule sticks to teeth, sticks to tissues, but then also kills off the bacteria," Dr. Szymanowski said, adding that stains are expected with that ingredient. "It's okay to have a little staining. We always inform our patients, and they know it's coming."

But that's the issue: They know it's coming.

The lawsuit claims that Crest has "actual knowledge that its product causes staining," and that "the warnings and directions that accompany Crest Pro Health mouthwash fail to inform consumers about the risk of tooth discoloration or loss of sense of taste."

Proctor & Gamble representative Laura Brinker says the company saw no need for a warning.

"Based on inquiries to consumer relations, we know that 99.9 percent of people who are using Crest Pro Health every day have not reported any such concern regarding tooth discoloration," she said.

But how many consumers does that represent in terms of real numbers?

"Well, it's difficult to talk about the real numbers because, as you know, they change every day," Brinker said.

In a July e-mail, Laura did say that the company had received 3,800 complaints, out of more than 100 million units sold, although consumer websites still claim that the mouth rinse has caused a significant number of stainings.

When asked if there was a chance the numbers could be higher because customers may not be reporting problems directly to the company, Laura Brinker acknowledged that may be the case.

On their website, Crest goes so far as to say that the brown staining is a sign that their mouth rinse is working.

"After the active ingredient kills the germs in your mouth, those dead germs can collect on the surface of your tooth and can actually appear as a stain," Brinker said.

Dr. Szymanowski said that may not be the best way to put it.

"Proof that it's working? No. Proof that something is there, yes," he said.

As for the issue of how people use the product, Dr. Szymanowski tells his patients to be aware their own behavior can make the staining inevitable.

"People who just drink wine, smokers, coffee, and even tea -- especially green tea -- has quite a lot of staining," he said.

People complaining about the staining want everything from the product pulled to just a warning, and Proctor & Gamble say they are considering making a change.

"We are anticipating some new language to our label," Brinker said, but was careful to point out it won't be a warning. "Because such a small percentage of consumers have actually reported this, we actually don't consider this a warning. We actually consider this a sharing of relevant information."

One complaint about the stains these chemicals can cause is that home cleaning won't remove them. Dentists say that a deeper cleaning, which can be expensive, is the only thing that will remove the brown stains on teeth.

Still, Proctor & Gamble believes the product is working as designed, even though the company will pay for cleanings of unhappy customers in some cases.

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