Testing at-home teeth-whitening products. - By Seth Stevenson - Slate Magazine

Testing at-home teeth-whitening products. - By Seth Stevenson - Slate Magazine: "Tooth whiteners are primed to be the next deodorant: a once-optional form of personal hygiene that's now simply an obligation. It's only a matter of time because the more of us who get whitened, the grungier your unwhitened teeth will appear in contrast. Man, look at those choppers! Nasty! Aren't you going to do something about that? There has lately been a boom in tooth-whitening techniques, both at home and in the dentist's office. I asked St. Louis-area dentist (and frequent Slate dental correspondent) Dr. William Hartel about the various options, then tried a few for myself. Below, my findings.
At the Dentist's Office
Dentists have been whitening teeth for years. You have two options here: 1) The dentist gives you special equipment, and you do it yourself at home, over a few weeks; or 2) the dentist does it entirely at his office, in a single day.
With Option 1, the dentist molds vinyl trays to fit your teeth. Then he gives you a prescribed gel to put in the trays. This gel will contain carbomide peroxide (which reacts with your saliva to become hydrogen peroxide) at a concentration somewhere between 10 percent and 25 percent. You go home, load the gel into the trays, wear the trays two to four hours per day for two to three weeks, and your teeth get whiter as the gel oxidizes their stains. This option has been available for more than a decade, and it works. You'll see a difference within two days. The whole thing costs about $200 to $400, and the effects won't wear off for several years.
Option 2 is actually the same thing but massively speeded up. The dentist puts the peroxide on your teeth and then uses a laser (or plasma arc lamp) to activate the oxidization and whiten your teeth much more quickly. You spend about an hour in the chair, an"