On the Bright Side

Philadelphia Inquirer March 10, 2003

More than 10 million Americans will likely get their teeth bleached this year, spending about $1.7 billion to gain a whiter, if not perfect, smile.

New processes have folks flashing those pearly whites
Marian Uhlman INQUIRER STAFF WRITER

First, fillings. Then braces. Now whitening.

The latest effort in America's quest for the perfect smile is focused on erasing the yellowing ravages of time and bad habits. To counter the effects of age, coffee, cigarettes and wine, more and more people are bleaching their teeth to a youthful gleam.

"It is incredibly popular," said Mark Meraner, a Temple University associate professor of restorative dentistry. "It is representative of trends in dentistry in general toward aesthetic procedures."

The search for a Hollywood smile has become so common that more than 10 million Americans this year are expected to get their teeth whitened, according to Martin Giniger, a dental professor at the University of Medicine and Dentistry of New Jersey and a consultant to the oral-care industry.

The number of customers has increased, as a growing array of whitening products has arrived on store shelves, costing between $15 and $30 each, Giniger said. And many others seek professional treatment from a dentist at a cost of $300 or more, he said.

The whitening boom - estimated at $1.7 billion this year - likely will not make America's mouths any healthier, Giniger said. Just brighter.

"We can basically take one part of the body and take away 20 years of aging," said Kimberly Harms, a Minnesota dentist and consumer adviser for the American Dental Association. "If you are 46, you can look 26 without exercise, diet or surgery."

Colleen Nihill, 26, of Center City, said she wanted to recapture the whiteness she had as a child.

"Professionally and personally, it is something that could help," said Nihill, a lawyer , who underwent an hour-long treatment in a Philadelphia dental office. "You have one time to make a first impression. And a smile is a large part of that."

Nihill said her friends noticed a difference after whitening, "but I wasn't blinding anyone with my teeth."

People have longed for whiter-looking teeth for ages. Even in the prehistoric era, people used sticks for teeth cleaning and stain removal, according to Paul Sagel, principle engineer for Procter & Gamble's Oral Care Product Development.

More recently, in the late 1800s, some people put acid-based chemicals on their teeth. While they could sport a frosted-looking smile for a while, the process dissolved their enamel, Sagel said.

Sagel, who developed Whitestrips for Crest, said people associate whiter teeth with cleanliness, healthiness and attractiveness.

Whitening came of age after scientists recognized that peroxide was a viable chemical for the job.

Whether performed in the dental chair or in a bathroom, bleaching involves coating teeth with a type of peroxide gel. Once in the mouth, Giniger said, the peroxide undergoes a chemical reaction: First, it breaks into water molecules and free oxygen radicals. Then, the oxygen radicals combine with carbon-based molecules in the stained teeth. The process turns stains clear.

Unlike whitening toothpastes, which use abrasives to clean the tooth's surface, the peroxides penetrate into the tooth enamel.

Giniger said bleaching falls into three general categories:

Chairside bleaching is performed in the office, where dentists can apply a higher percent of peroxide in combination with a light - typically in the blue to ultraviolet spectrum - to speed the process. Dental dams cover patients' gums to protect them from the chemicals.

Tray-based bleaching is a take-home professional treatment option. Dentists custom-make trays into which patients insert a peroxide gel. Patients then bring them home to wear, usually twice daily for about two weeks.

Over-the-counter kits involve three main approaches, which also require about two weeks of daily applications. Mouthguards require patients to boil and mold a plastic material into a tray and apply a peroxide gel. Whitening strips are pre-loaded with peroxide and are placed on the teeth. And paint-on gels involve applying peroxide directly onto the teeth.

The American Dental Association encourages people to consult with a dentist to determine the most appropriate treatment. Not everyone's teeth will respond to bleaching, the group says. For instance, yellowish teeth will likely bleach well, but grayish teeth may not at all. And the results for brownish-colored teeth probably will be somewhere in between.

Giniger said professional treatment usually trumps over-the-counter kits for whitening because dentists can offer higher concentrations of peroxides.

In any form, he said, peroxide gels are safe when used as directed. If problems arise, they usually involve gum irritation or tooth sensitivity.

A study last year in the Journal of the American Dental Association suggested that one in two people experienced temporary tooth sensitivity when using a home whitening treatment under dental supervision. The study involved 100 patients fitted with a custom mouth tray. Half were randomly assigned to receive a carbamide peroxide gel and the other half were given a placebo gel.

Most dentists still use the trays, Giniger said, but he expects office-based peroxide treatments using light "will become the standard of care." Not only is the approach "safe and effective," he said, but it offers patients a time-saving option to dental trays and over-the-counter products. Hence, a competitive advantage (though a more costly one).

An article in last month's ADA journal suggested that peroxide and light increase the tooth whitening effect more than peroxide alone.

The American Dental Association does not have a position on the use of light, said Kenneth Burrell, senior director for ADA's Council on Scientific Affairs. If people are concerned, he said, they should ask their dentist what kind of light is being used and whether it could cause a problem for them. Ultraviolet light, for instance, can pose minimal risk to patients taking certain drugs for other conditions, Giniger said.

Paul Berson, a University of Pennsylvania clinical assistant professor of restorative dentistry, said he used the tray system until about two years ago, when he switched to the in-office bleaching process with a light. Wearing trays correctly will whiten teeth, he said, but he found patients often skipped treatments. Berson said about 95 percent of his patients report no side effects from the process. The rest have varying degrees of tooth sensitivity lasting no longer than 24 hours, he said.

Regardless of the whitening method used, experts say, the results will fade over time - and more quickly if people return to cigarettes, red wine, coffee and tea.