Behind Jessica Simpson's Sinful Smile

April 30, 2010 — -- Normally, people might hesitate to air their bad habits before millions. But Jessica Simpson is not normal.

Wednesday on the "Ellen" show, one day after she admitted to Jay Leno that she chomps on Nicorette gum not because she ever smoked but because she loves the buzz she gets from it, the pop-turned-country singer revealed she brushes her teeth "maybe three times a week."

Simpson said she has good reason to shun the twice-a-day rule followed by most humans in developed nations, and strongly recommended by the American Dental Association:

"My teeth are so white and I don't like them to feel too slippery but I do use Listerine and I do floss everyday," she said. "But I don't brush them every day. ... My lips just slide all over the place ... I can't catch up with my mouth. I need a little coating."

Instead, she's figured out a better system: she uses "a shirt or something" to wipe her teeth. And since she's not repulsed by her own breath, everything must be fine!

"I know it's gross but I always have fresh breath," she laughed. "It's really weird but I have great breath."

Be that as it may, Simpson may not care so much about what's coming out of her mouth when she has no teeth in it. Since she's the host of VH1's "The Price of Beauty" and an ambassador for Operation Smile, pearly whites are kind of essential to her career. According to dentists surveyed by ABCNews.com, by not following the basic tenets of brushing, Simpson is committing sins that could damn her to oral hygiene hell.

"The biggest risk she faces is losing her teeth," said Dr. Sally Cram, a periodontist and American Dental Association consumer advisor spokesperson. "You need to remove the plaque and bacteria that build up under your teeth and gums at least every 24 hours. If you don't and you let that bacteria collect for two or three days, you start losing bone around the teeth and that can lead to decay."

Dentists: Jessica Simpson, Please Brush Your Teeth

The problems extend beyond Simpson's mouth. While the former Mrs. Nick Lachey and the ex-girlfriend of both John Mayer and Tony Romo may be single now, at the age of 29, she could be looking to have a child soon. Bad gums don't bode well for babies.

"A study at the University of North Carolina showed that women who were pregnant and had bleeding gums or bad oral hygenie were seven times more likely to give birth to premature, low birth weight babies," said Los Angeles-based dentist Dr. Harold Katz.

And polishing her pearly whites with a shirt won't ward off gum disease.

"Think of your gum as a little turtleneck collar around your tooth," said Cram. "Your job every day when you brush is to sweep down under that collar and take out the bacteria. That shirt isn't really going to get in between teeth and it's not going to get down underneath the gum collar."

Potential suitors, beware: whatever she doesn't rub off with that shirt, Simpson could pass on to you.

"She's gaming the system by trying to polish the front part of her mouth but the rest may be full of plaque," said Katz. "She should be careful about kissing or biting people. She may be transfering the bacteria from the back of her mouth to her tongue and on to them."

To be fair, if Simpson is indeed flossing daily, she's got the hard part down.

"If we take her at her word, flossing and using an antibiotic rinse daily, those are two legs of the same stool. But you need the third leg, brushing, to get optimum oral hygeine," said Dr. Matthew Messina, an Ohio-based dentist and ADA consumer advisor. "It could be that some of her aversion to brushing is because she's going about it the wrong way. Maybe she was brushing too hard. A lot of times, it's simply a technique issue."

Jessica Simpson, Dentists' Nightmare

But then there's the issue of her breath. While Simpson can swear up and down that it's "fresh" and "great," dentists agree that she's not in a position to make that call.

"You cannot smell your own breath," said Katz. "She's probably used to her own odor. It's a process your brain goes through called acclimation. That's probably why she doesn't have a boyfriend at the moment."

"I have a device called a Halimeter that actually rates your breath, and gives it a numerical score," he added. "I'd be happy to fly wherever she is right now to test her breath for her, and then she can announce the results -- good or bad."

Or she could go another route.

"Perhaps she should ask some of her friends, acquaintances or family members," said Cram. "Quite often, people are hesitant to tell someone they have bad breath."

Paging Mr. Mayer: here's a chance to put your tweets to good use.