A Checkup on Whiteners

So Many Ways to Brighten Your Teeth, So Few That Are Worth the Money

Most cosmetic procedures have both critics and disciples. For every face-lift, nose job, baldness fix or hair removal scheme, there's one camp that finds the whole thing ridiculous and another that can't face the future without it.

But tooth whitening has few public foes: Who stands in favor of yellow teeth? So the question for those with teeth the shade of a manila folder isn't whether to whiten but how. Here we present a guide to the bewildering array of rinses, pastes, trays and treatments only your dentist can do.

It's hard to find a tooth-whitening expert who isn't somehow affiliated with a maker of tooth-whitening products. For this story, we checked with two widely published researchers whose work consistently appears in peer-reviewed journals: Gerard Kugel, associate dean for research at Tufts University School of Dental Medicine (who has been paid for research by Ultradent Corp., Discus Dental and Procter & Gamble), and Robert Gerlach, principal scientist for Procter & Gamble (maker of Crest products). We also spoke with representatives of companies that make other whitening products and read published research.

A few overarching points:

· Conventional wisdom -- touted mostly by dentists themselves -- holds that you should have a dentist check your mouth for decay or disease before embarking on your tooth-whitening journey.

· Whitening products take two basic approaches. Some contain bleach that permeates the teeth to remove both internal, or "intrinsic," stains and those on the outside of the teeth. Others use mechanical or chemical means to loosen or buff away the junk that stains the outside.

· Most experts agree that the effectiveness of any tooth-bleaching method comes down to two factors: the concentration of bleaching agent (usually hydrogen peroxide or carbamide peroxide) and the length of time that agent is in direct contact with the teeth.

Matt Messina, a Cleveland dentist and the American Dental Association's go-to guy on whitening, says, "Whitening is basically a continuum. The less expensive, less involved procedure produces lower results, while the most expensive, more complicated procedures can produce dramatic changes in color. There is no one right answer."

Connecticut dentist Marty Zase, president of the American Academy of Cosmetic Dentistry, notes that, for treatments done by a professional, the cost of whitening is determined by the dentist's location, experience and skill. Any dentist can call himself a cosmetic dentist; to find one with extra training, go to http://www.aacd.com/ . Ask to see photos of a whitening the dentist has actually performed, Zase suggests, and don't be shy about asking for references.

The American Dental Association says whitening is a pretty safe procedure. But bleaching agents can cause short-term tooth sensitivity and, if poorly applied, temporarily make your gums and other parts of your mouth hurt. Both problems should go away if you lay off the bleach for a day or so.

The Food and Drug Administration regards tooth-whitening products as cosmetics, not drugs. So as long as manufacturers don't say their products cure or prevent disease or make other health claims, they're free to say just about anything they like without substantiating those claims with research. So it's up to you, oh dingy-toothed one, to choose carefully. ·

Jennifer Huget is a frequent contributor to the Health section.