Mona Schlater-Hewlett, 45, was in the middle of an aerobics class at the gym when she felt a piercing pain and dropped to the floor. But it wasn't a strain in her muscles that brought her down—it was her teeth. "It came out of nowhere," recalls Schlater-Hewlett, a program advisor for the Los Angeles School District. "All of a sudden, I was buckled over, my hand over my mouth, with this pass-out-on-the-floor kind of pain. People came over to me and asked, 'Are you okay?' "
The source of her misery: A tray full of tooth bleach that she'd worn to bed the previous night.
Schlater-Hewlett was using 10% carbamide peroxide gel in a custom-fitted bleaching tray—all of which was prescribed by her dentist. Although you can buy stronger teeth whitening gels, this is the only home teeth whitening treatment to earn the American Dental Association's seal of acceptance. She tried taking a month off before returning to her schedule of bleaching. She even used desensitizing gel before and after treatment.
But her "zingers"—the term dentists use for these sharp pains in the teeth, which can last for several minutes—persisted, and she had to give it up. Schlater-Hewlett eventually got veneers for her teeth, a more elaborate and expensive option. "I'd never try bleaching again," she says.
Teeth whitening has become a big business. Americans spend billions on teeth whitening products annually, and in dentists' offices, bleaching is the most requested procedure among patients ages 40 to 60, according to a survey conducted by the ADA. And teeth whitening toothpastes are now more popular than any other kind. Bleaching has entered its golden—or shall we say porcelain—era.
But the dangers of teeth whitening are causing problems. Schlater-Hewlett's dentist (who happens to be her husband) is unsure what caused her pain, but her experience isn't as rare as you might expect. In a 2002 University of Southern California School of Dentistry survey of 100 people, half experienced mild to moderate sensitivity after using an over-the-counter-strength whitening gel (15% carbamide peroxide), while 1 in 25 had the kind of pain Schlater-Hewlett suffered.
As more and more patients report trouble, dentists are scrambling to identify who makes a good candidate and who should skip the procedure. The answers are becoming clearer, but researchers are also uncovering what may be the true hazard of whitening—a pursuit of bleached perfection that leads to overuse of these chemicals.
Although more than a third of adults worry that professional teeth whitening will damage their enamel, research suggests that their fears are unfounded. "There's overwhelming evidence that, when used as directed, bleaching does not cause permanent damage to the teeth or gums," says Edmond R. Hewlett, DDS, consumer advisor for the ADA and an associate professor at the UCLA School of Dentistry (and Schlater-Hewlett's husband).
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[pagebreak]Studies have shown that it's safe to undergo a course of bleaching—2 weeks with a drugstore method or a dentist-prescribed night guard, or a single in-office power-bleaching session—once or twice a year. But dentists are less confident about the safety of using the chemicals as simply another part of the morning shower-shave-brush grooming routine.
In addition to tooth sensitivity, dentists report seeing side effects that include gum irritation, bluish enamel, uneven whiteness, and—if the chemical manages to seep into a cracked tooth or an unfilled cavity—painful internal damage that can lead to a root canal. Except for that last one, side effects of teeth whitening products usually clear up within a couple of weeks, provided you stop using the chemicals.
Unfortunately, many people don't stop when they should. "Ten years ago, people weren't even aware of bleaching," says Irwin Smigel, DDS, president of the American Society for Dental Aesthetics. "Now every dentist I know has had to cut off at least one patient because of overbleaching. People come in with great, great pain, and I can see immediately from the color of their teeth and the irritation along the gums that they've been bleaching and bleaching."
The urge to keep whitening may spring from the fact that teeth stubbornly refuse to maintain their same sparkling brightness for long. "Once you stop with the bleach, it regresses—your teeth start returning to their original color," says Smigel. "Very few people are happy with the color once it starts regressing, so they'll do teeth whitening again and again." Dental laboratories are working to keep pace by creating new caps, fillings, and crowns in ever-brighter shades.
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For some individuals, the pursuit of blindingly white teeth can become a true obsession. "There's anorexia nervosa among certain people who desperately want to be thin, and there's also a similar syndrome for people whose teeth are never white enough," says John W. Siegal, DDS, a New York City dentist. This can go so far as to be classified as a form of body dysmorphic disorder (BDD)—a distorted view of one's features that becomes so consuming that it interrupts daily functioning and requires psychiatric treatment—says Katharine A. Phillips, MD, a professor of psychiatry at Brown Medical School.
In a study she conducted of 200 individuals with BDD, 59 of them, or nearly one-third, were found to be excessively focused on the appearance of their teeth and bleached compulsively as a result, regardless of uncomfortable side effects.
"I can see how addiction happens," says Laurie Hardjowirogo, 54, a graphic designer from Manhattan. She first whitened her teeth 5 years ago, when her dentist made her a custom-fit bleaching tray. She touches them up once a month (most dentists recommend touch-ups every 4 to 6 months).
"Now my much whiter teeth seem like they're the way they're supposed to be," she says. "But I don't know if I have a fair assessment anymore because so many people are doing it. I don't know where the bar is anymore—I look around at other people and think, 'Is that normal? Is that too much?' "
The good news: As long as you keep your expectations realistic and understand that these strong chemicals need to be handled with care, the procedure seems safe. The best approach is to heed the advice of a dentist or the product label—and keep some perspective. "You can go only so white with bleaching," says Smigel.
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By knowing what to expect and why you should exercise a bit of self-control, you can determine which method of teeth whitening is best for you, reduce the risks, andget your teeth gleaming white. Here's a look at the options, the risks, and the results you're likely to get from teeth whitening.
Many of us know the slack-jawed stupefaction that can result from staring at a drugstore shelf stuffed with bleach kits. Still, these over-the-counter teeth whitening methods--by far the most economical kind--are worth trying before you spend big money on in-office procedures.
How safe are they? The more closely you adhere to the instructions on the label, the better your odds of avoiding side effects. But have your dentist check your mouth first, even if all you crave is a little over-the-counter brightening. The ADA hasn't granted its seal of acceptance to any OTC bleaching method in part because if the mouth isn't healthy when bleach is introduced, serious problems can result.
"One woman came in to see me today with a lot of pain," says Smigel. "She bought a home-bleaching kit, and she used it when she had a cavity. Now she needs a root canal." Similar reports have indicated that if bleach gets into the pulp (the nerve chamber) of the tooth through a crack or a filling, it can cause severe pain and require treatment.
Another word of warning: "These products lend themselves to continuous use," says Smigel, "and that's when you really start to see pain, irritated tissues around the teeth, and teeth that take on an unnatural, bluish, translucent look." Though harmless, the tint can be permanent. Kits with mouth guards may carry additional risks because ill-fitting trays can press peroxide onto gums or allow the solution to spill out, causing irritation. Obviously, stop using the product and see your dentist if you experience any pain.
How well do they work? "Some people can get good results with an over-the-counter product," says Hewlett. A study from the School of Dentistry at the University of North Carolina suggested that over-the-counter teeth whitening strips, dentist-prescribed bleaching trays, and in-office bleaching sessions can ultimately produce the same pearly shade. That's because all these teeth whitening methods rely on one of two active ingredients: hydrogen peroxide or carbamide peroxide (which breaks down into hydrogen peroxide over a few hours).
In minutes, a dentist can mold a bleaching tray to a person's mouth and prescribe a bleaching gel to go with it. And when your dentist is involved, you minimize the risks—and you're more apt to get quick treatment if trouble develops.
How safe is it? The 10% carbamide peroxide solution with a custom-fit tray is the only take-home teeth whitening treatment that the ADA feels comfortable recommending. Here's why: A lot of research, including a 2004 study from Tufts University School of Dental Medicine, has shown that customized mouth guards help ensure that the bleach stays in contact with the teeth for maximum whitening, while minimizing the amount of potentially irritating bleach that can dribble onto the gums and soft tissues of the mouth (in contrast to the one-size-only trays sold in drugstores).
What's more, if a patient experiences sensitivity, a dentist can prescribe a lower concentration of the bleach or give the patient a desensitizing gel to use for a few minutes just before or right after bleaching.
Dentists provide enough gel for one 2-week treatment per year, plus 1- or 2-day touch-ups every 4 to 6 months. This limited supply may help keep you from going overboard—provided you can keep your hands off over-the-counter teeth whiteners in the interim. If you start alternating prescription-strength bleach with an OTC option—to continue daily bleaching for months--the risk of gum irritation, sensitivity, and translucent teeth increases, says Smigel.
How well does it work? This mode of bleaching has been shown to whiten dramatically, taking teeth from yellow to much whiter after 2 weeks of nightly treatment. The typical improvement is about four or five shades.
The "power bleaching" treatments offered in dental offices and teeth whitening chains like BriteSmile deliver results in the shortest amount of time—a little over an hour. Special lights speed the action of a highly concentrated bleaching gel that's been applied to the teeth.
How safe are they? Used in-office, gels that contain 35% hydrogen peroxide have earned the ADA seal of acceptance for safety and efficacy, but that doesn't mean they're free of side effects.
"With these techniques, there have been reports of increased sensitivity of the pulp chamber in the middle of the tooth," says Siegal. Dentists say there's no sure way to avoid such sensitivity, which can last a few days; some patients have reported discomfort up to 3 months later. And the bleaches used are so strong that they could "very easily chemically burn anything soft in the mouth—the gums, the skin, the tongue," says Hewlett.
That's why the dentist or hygienist must take precautions, such as carefully applying a protective, plasticlike gel over the gums and using a retractor, rubber shield, or dental dam to pull back lips and protect gums.
How well do they work? Light treatments get big results fast—brightening teeth by up to eight shades in one to five sessions—and most of the lightness gained from a power-bleaching session lasts a year or more. But a study from Tufts University School of Dental Medicine showed that a week after the teeth whitening treatment, subjects saw an average "shade rebound" of two shades.
Dentists say this is partly because teeth become especially vulnerable to stains right after a bleaching. "Your teeth are covered by a protective layer called a pellicle," says Siegal. "The power-bleaching process removes it, so teeth tend to absorb stains much more readily." It's essential to avoid dark foods and drinks—tea, coffee, cola, blueberries, dark chocolate, red wine (and smoking)—for at least 24 hours, as the pellicle begins to reform.
Brushing right after consuming those foods and beverages—or at least swishing a little water around in the mouth—can help keep staining at bay. Make this part of your regular smile care, and you'll add on months to your results.
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