They're the first thing Matt Harris notices when he makes an acquaintance.
"The way people care about their teeth tells a lot about them," says Harris, who sees his share of discolored and stained teeth as an assistant in Dr. Kyle Coble's office.
Harris isn't the only one who believes in the power of a Pepsodent smile.
The almost obsessive quest for a sparkling smile has erupted into a billion-dollar industry. In just five years, sales of tooth-whitening products have spiked more than 300 percent.
"Tooth-whitening is the No. 1 requested dental procedure," said Eric Nelson, spokesman for the American Academy of Cosmetic Dentistry, among the country's largest dental associations.
Whiteners run the gamut from tooth polishes to dentist-administered bleaches. TV commercials hawking pastes, paint-on gels and whitening strips promise to polish even the palest porcelains. Dentist offices are swamped with requests for tooth-whitening procedures that can cost up to $600.
What's behind this infatuation with iridescent ivories?
Flash a snappy smile and you'll make a lasting impression, say 90 percent of the people surveyed by AACD.
Display a distasteful one, most say, and the opposite sex runs the other way.
A loathsome look might even cost career success, say most polled.
Half of the people interviewed were happy with their own smiles. That leaves the other half who want to improve them.
"People want to look young," said Fredericksburg dentist Dr. Stan Dameron. "A smile is the first thing you see in a person. No matter how pretty or handsome they are, their teeth make an impact."
And the whiter the better.
"In a layman's mind, white teeth translate into beautiful teeth," said cosmetic dentist Dr. Thomas Phillips of Fredericksburg.
The pursuit of the snowy-white Chicklets has prompted a change in the shades of porcelain dentists use for dental procedures.
"We used to try to make teeth look natural," said Coble, a dentist in southern Stafford County. "In many cases, people don't want that. Sometimes we feel we're making them too light."
The craze transcends age.
Patients from their teens to their 80s request whiter teeth.
Women want it more than men. So do baby boomers in their 40s and 50s.
Toothpastes rank low on the tooth-whitening scale; paint-ons are a little better.
"Over-the-counter toothpastes rarely do much that you can see," Dameron said. "I've never seen any that made a difference."
Whitening strips that can be purchased from the drug store provide better results, but they have their limitations. They're easier on the pocketbook (about $30) than dentist-supervised whitening, but take longer to show results.
Two other procedures are available only in the dentist's office.
One includes peroxide gel trays with individualized reservoirs for each tooth. The custom-made trays fitted at the dentist office are worn at home for several hours or overnight. They may be reapplied periodically using the same trays.
The trays cost from $300 to $400 for upper and lower teeth. Additional solution for reapplication costs $30 to $40.
Whitening kits also are available over the counter with standard trays that claim to fit any mouth. They also contain significantly lower doses of peroxide than the dentist-supervised trays.
"My concern is if the tray doesn't fit, you can get gums that ulcerate and recede," Dameron said.
A stronger procedure employs a type of power bleach using carbamide peroxide and a high-intensity light or laser.
It takes less than an hour in the dentist chair. It also carries a hefty price tag of $500 or more for the whole mouth.
"We tend to encourage the trays that the dentist makes," Dameron said. "The end result is as good, but not as fast."
Even the best tooth-whitening methods can't ensure sparkling white choppers. Not everyone's teeth respond the same.
"Some people are going to bleach more quickly and easily," Coble said. "If they have fillings, the natural tooth structure may bleach lighter and we may have to replace fillings."
Coble advises patients who are considering tooth-whitening to have it before the dental work is completed.
Whitening procedures can cause a mild sensitivity in teeth and gums that is usually temporary, Coble said. That lasts only a short time, with no long-term effects.
Matt Harris, who is 18 and lives in Stafford County, chose the dental trays. He wanted to remove stains on his teeth from childhood and has been whitening his teeth for about two years. He reapplies the solution as he feels he needs it.
His glowing smile has spurred others in pursuit of pearly porcelains.
"He's got my girlfriend and her friends hooked," said Clint Novak, a disc jockey at WBQB radio station in Fredericksburg where Harris also works as promotions assistant. So far, Novak has resisted the impulse to bleach his teeth, but concedes that he's tempted to try it.
"I want white teeth," Novak said. "I just don't want to do all that is required."