Jewish World Review Jan. 13, 2003 / 10 Shevat, 5763

Blinded by the white

Light speeds new whitening treatments. But research on long-term effects is spotty

By Jennifer Huget | Maybe we all figure we're just a few shades of dental whiteness away from looking like Julia Roberts or Tom Cruise. Or maybe it's just the innate human urge to sit in a dentist's chair for an hour with our lips retracted and a light aimed at our teeth. Whatever the motivation, Americans will spend an estimated $1 billion this year having their teeth professionally whitened. And increasingly, people are choosing to spend even more money to have it done faster, via relatively new, aggressively marketed "one-hour'' tooth-whitening procedures.

While nobody is quite sure how many people have partaken of one-hour whitening or exactly how much they've spent, market leader BriteSmile claims to have whitened close to 500,000 smiles nationwide since 1999, at prices ranging from $400 in the Baltimore area to as much as $780 in the Washington, D.C.. area and up to $1,200 in Manhattan. With its services being performed at dentists' offices (103 of them alone in the Washington, D.C., area) and at BriteSmile Spas scattered across the nation, BriteSmile has achieved high visibility in part by spending $60 million, according to the company, on marketing. That works out to about 120 promotional dollars per customer so far.

While tooth whitening in general is starting to catch on in Europe and Japan, whitening guru Van Haywood, D.M.D., of the Medical College of Georgia (he pioneered tooth bleaching in the United States and has written more than 60 publications on the subject) says that those populations are about five or 10 years behind States, both in terms of access to the latest technology and in the number of people taking advantage of available techniques. Laser- and light-enhanced whitening systems, Haywood says, are not widely available outside the United States.

But even as hordes of dentists and patients jump aboard the whiter-in-an-hour train, some quiet voices in the dental profession are urging caution, noting that some speedy whitening processes subject teeth to unusual heat and stress and that the procedure has not yet been subjected to enough scientific scrutiny to ensure that it's safe.

Among the cautious is Jason Psillakis, a dentist with Columbia-Presbyterian Dental Faculty Practice in New York. "There's not enough research'' supporting the procedure's safety, he said. "Any type of light generates heat,'' and the effects of that heat on dental health are not known. Before integrating one-hour whitening into his practice, he said, "I'd want to know that the long-term effects are. Once I have that information, I can make an educated decision.''


Until the advent of speed bleaching about a decade ago, tray-and-gel systems were the state of the professional whitening art. For about $300 to $500, patients seeking to brighten their choppers get a dentist to craft a custom-made set of mouth-guard-like trays, into which the patient, at home, squirts a 10 percent hydrogen peroxide gel. The trays are worn for several hours at a time, sometimes overnight, and for several days in a row until the desired whiteness is achieved.

While the results can ultimately match those reached through power bleaching, it takes patience and persistence to get there via tray-and-gel. The trays can be messy and uncomfortable; gel can leak out into the mouth and irritate the gums and other soft tissue. Compliance with the goopy routine can be problematic. Those with sensitive teeth or gums may need several days between treatments to recover from toothache-like pain and mouth irritation, further reducing compliance.

By contrast, one-hour whitening requires minimal patience and no persistence. Whether referred to generically as chairside or power bleaching or by high-profile brand names like BriteSmile, Zoom! and Rembrandt, accelerated tooth-whitening processes derive their speed from light sources: lasers, plasma-arc lights, specialized blue-green spectrum lights, and even the regular lamps you stare into whenever you get your teeth cleaned.

As with tray systems, the whitening itself is performed by good old hydrogen peroxide, in concentrations ranging from 15 percent to 50 percent. In most accelerated whitening systems, light is aimed at teeth coated with hydrogen peroxide gel, and the heat generated by the light acts as a catalyst, speeding the bleaching process.

BriteSmile uses a blue light, housed in a lamp designed to illuminate all the "smile teeth'' at once; other systems employ hand-held lasers as catalysts and treat one tooth at a time. Such devices can cost around $5,000; BriteSmile doesn't charge dentists for the light itself, but instead collects $250 per procedure.

In BriteSmile and the other accelerated whitening systems, the dentist examines the patient to rule out tooth decay and other conditions that could make bleaching inappropriate. If all is well, the patient's lips are retracted with plastic devices and a blackout coating is painted over the gums. The dentist usually inserts a suction device to keep saliva from pooling in the mouth.

Most treatments involve three or more applications of gel, each left on the teeth for 10 or 15 minutes and then removed. Because the light is carefully aimed at their teeth, patients are required to sit still for the duration, their lips stretched wide by the retractors. Some practices offer stereo headphones and other diversions; hard as it is to believe, some practitioners report their patients are able to nap. Though the treatment itself generally takes an hour, the complete office visit will take closer to two.

Most dentists offering power whitening also prepare custom bleach trays for their patients to take home, either to boost the whitening further after the initial sensitivity has subsided or just to touch teeth up when, inevitably, they begin to yellow once again -- which can start to happen within months or hold off for as long as three to five years, depending on the teeth and their owner's diet. (Red wine, coffee, blueberries and cigarettes are among the indulgences that speed the yellowing process.)

The process lightens teeth by as much as 12 to 13 shades, "assuming the patient has that far to go,'' says Matthew Messina, a spokesman for the American Dental Association (ADA). That assumption in itself can be problematic: Messina notes that that power bleaching can produce unnaturally white-looking teeth and cautions that not everybody should shoot for the top of the whitening scale. A person's age or complexion may dictate that "china-white teeth would be out of place,'' Messina says. In any case, he adds, there's no denying that it is an "event'' for the teeth to endure.

"The teeth get dried and heated,'' Messina explains. "Some patients have discomfort for 24 to 48 hours after the procedure, a buzzing or dull ache in the teeth.' All of these are usually easily treated with Tylenol or Motrin.

Discomfort isn't peculiar to power whitening. But while hydrogen peroxide (and its relative, carbamide) often causes temporary thermal sensitivity and can irritate the lips and gums, it is generally deemed safe and is not thought to cause any long-term damage to the tooth's structure.

The jury is still out, though, on what happens when you add heat to the equation. While light-enhanced whitening hasn't been shown to be unsafe, some note that it hasn't been proven safe, either.


In his capacity as a member of the ADA's Council on Scientific Affairs, David Sarrett, a professor at Virginia Commonwealth University School of Dentistry, was asked to write a roundup on tooth-whitening procedures. His article, which appeared in the November issue of the ADA journal, weighs the benefits and risks of the full range of science-supported tooth-whitening procedures.

Laser- and other light-enhanced procedures merit but a single sentence in this four-page document. (For the record, Sarrett's article also calls attention to risks associated with unsupervised overuse of over-the-counter whitening products.)

"There is a lot of marketing hype on the use of lights and laser light, but little science to back it up,'' Sarrett said. "There is little published scientific evidence that the use of light, either laser light or other light sources, results in more effective tooth bleaching and is as safe as other proven methods.''

By contrast, the report stands solidly behind the dentist-administered custom-tray-and-gel procedures. This system, Sarrett notes, "has the largest body of scientific evidence supporting it of anything in dentistry,'' not just in the tooth-whitening realm.

Sarrett says the heat used in the one-hour process is a particular concern. "It doesn't take too much of a temperature rise to damage the pulp,'' Sarrett says.

Since patients aren't anesthetized during tooth whitenings, Sarrett notes that they can report any pain they might feel during the procedure -- pain that could signal potentially damaging temperatures. But because different patients have different pain thresholds, he says, that's not a reliable gauge.

"I have no evidence that there's any problem'' with light-enhanced whitening processes, Sarrett emphasizes. "There's just no evidence that they've been evaluated under scientific rigors and published in peer-reviewed journals. I'm sure these companies have done a lot of research, but they don't publish it and subject it to scientific scrutiny.'' He is familiar with four abstracts of BriteSmile research, most of it related to efficacy, presented at an ADA meeting but never published in full journal article form; at least one of the studies was funded by BriteSmile.

According to Richard Felton of the FDA's Center for Devices and Radiological Health, lasers and other devices used in tooth-whitening or other dental office procedures (most commonly as aids in curing restoration materials) must be shown not to "generate temperatures that were known to be damaging to the pulpal chamber.''

But BriteSmile's blue light and many similar products -- some of whose purveyors take pains to make clear that their devices are not lasers -- aren't classified as medical devices, so they are not subject to FDA approval or pre-market testing. Ironically, then, the scary-sounding lasers -- which Felton says people think of as cutting tools, not simply as the controlled light sources they are when used in tooth whitening -- are backed by more thoroughly vetted safety data than the benign-sounding blue light.


Quality research takes time, said BriteSmile's inventor, former NASA scientist John Warner. BriteSmile, he says, has taken the lead in funding scientific research, and some of its studies should start appearing in journals over the next two years -- if they are accepted by those journals.

Six studies of BriteSmile's safety and efficacy are available for perusal at, he added. If publication of studies in scientific journals is to be the standard, Warner added, "In two years, BriteSmile will be the only one on the market.''

Warner observed that there are important differences between his product and others in the field. First, BriteSmile's gel contains only 15 percent hydrogen peroxide, a concentration calculated to minimize soft-tissue irritation. Moreover, Warner says, his gel is designed to be activated by BriteSmile's proprietary blue light, which he says is safer than visible light because it lacks the damaging ultraviolet wavelengths. The light generates very little heat, he adds.

No light-enhanced whitening system has received the ADA's seal of acceptance, a voluntary program through which companies submit their products for review.

Warner acknowledged that there is a certain prestige associated with the seal and says BriteSmile wouldn't mind having one. But that's not likely ever to happen. Though the company submitted, and the ADA accepted, its safety and efficacy studies, Warner explained, the ADA "did not give us the seal because of our wholly owned centers that do only BriteSmile. The ADA wanted to see ongoing care. But we will not change our business model'' just to earn the seal, he said.


Daniel Deutsch of the Washington Center for Dentistry said his practice (which serves about 6,000 patients) does about 25 or 30 BriteSmile whitenings per month, many of them on referral from other dentists who lack the equipment or experience to offer the service themselves.

Deutsch favors BriteSmile over tray-and-gel whitening because he found that with many patients, "you give them something to take home, they won't do it. I would find the compliance wasn't that good.''

"The nice thing about this system,'' Deutsch says, "you do it and it's done.''

But Bruce Steele of Georgetown Dental in Washington, D.C., said his practice isn't ready to augment its tray-based, take-home whitening system with lights or lasers because "I'm not 100 percent comfortable with the procedure. I'm not entirely sure of its safety. I'm concerned about how much heat we're putting on teeth,'' Steele said. "I'm waiting for the science.''

Adding to Steele's discomfort is the fact that he has undergone power bleaching himself. His experience with the Zoom gel-and-light system "was a very unpleasant hour,'' he said. "You need to sit still. It's tedious, uncomfortable. Not for the claustrophobic.'' (Zoom's own Web site notes that the procedure may not be appropriate for those with strong gag reflexes or anxiety problems.)

Which is not to say that Steele has ruled out ever hopping on the accelerated-whitening bandwagon. "We have people calling us all the time to see if we do'' one-hour whitening, he said. "That's what makes it tempting.''

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