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Whiteners Work, but Consult Dentist

By Joanne Kabak | Joanne Kabak is a freelance writer.

March 4, 2003

THE PRODUCT AND WHAT IT'S MARKETED FOR: Procter & Gamble's Crest Whitestrips, marketed as a product that creates "noticeably whiter teeth," is sold on store shelves in a set of 56 strips for $29.95. The at-home procedure calls for you to apply the strips to teeth twice a day, 30 minutes at a time, for 14 days. With sales of more than $250 million since its retail launch in 2001, Whitestrips is the leader in a booming market for whiter teeth, said company spokesman Brian McCleary. Competitors include over-the-counter options like Colgate's Simply White, and lesser-known brands, which often are distributed through dentists' offices.

WHAT'S KNOWN: When you "whiten" your teeth you actually are "bleaching" them with hydrogen peroxide, a treatment that used to be available only from a dentist. In a study reported in its February 2001 newsletter, the Clinical Research Association, an independent group that evaluates dental products, said that Whitestrips and 22 products used in dental offices all whitened teeth, since "all use the same hydrogen peroxide active ingredient." What differs is the amount of hydrogen peroxide and the method by which it is applied. While many products use a tray filled with gel, Whitestrips has a thin flexible strip saturated with 6 percent hydrogen peroxide; Simply White has a brush to paint the bleach on. In a December 2002 random study of 32 people, paid for by Procter & Gamble and conducted by Dr. Ingvar Magnusson at the University of Florida College of Dentistry, 94 percent of those who used Whitestrips said they had meaningful whitening, a change that was supported by digital imaging. In its September 2000 report, the Clinical Research Association noted that 77 percent of users and association evaluators rated Whitestrips "excellent or good and worthy of trial"; one of the disadvantages was that "strips were difficult for some people to handle."

THE BOTTOM LINE: While hydrogen peroxide long has been used safely in oral products, there are gaps in knowledge about its use in over-the-counter whiteners. For example, the Food and Drug Administration has been in limbo since the mid-1990s on this topic. "The question is: Are they new drugs or cosmetics?" said Kathleen M. Kolar, FDA spokeswoman. While the agency initially said that tooth whiteners were subject to its rigorous new drug-approval process, it began to re-evaluate that decision after one of the manufacturers sued, Kolar said. For its part, the American Dental Association has decided to make over-the-counter whiteners ineligible for its Seal of Acceptance, a 70-year-old program that sets rigorous criteria. The association does evaluate dentist-dispensed whitening treatments and over-the-counter whitening toothpastes. Clifford Whall, Seal program director, said the decision is based on the ADA's belief that "professional consultation is important to the procedure's safety and effectiveness." For example, bleaches will not whiten restorative work, such as crowns and veneers, which could lead to uneven coloring.

OTHER APPROACHES: Practice good home care, including brushing regularly and avoiding liquids that cause stains, such as coffee, tea, red wine and colas. Try whitening toothpastes. Although they remove only surface stains, not the deeper ones that bleaching reaches, they do contain abrasives such as the mineral silica or enzymes. Check with your dentist to understand your individual case, and evaluate all your choices, which include bleaching in the dentist's office using a much higher level of hydrogen peroxide in a much shorter time or taking home a dentist-dispensed kit (Whitestrips has a professional version.) Considerations include cost, the location of your restorative work and your own consistency in following directions. Also, bleaching lasts only about six months to a year. Whatever you choose, be realistic. Hydrogen peroxide is an active chemical sitting on your teeth and gums for a period of time, and that means possible side effects, like teeth sensitivity or gum irritation. Like most forms of beauty, Magnusson noted, "shades of white are in the eye of the beholder."