Watch a film or television show from a couple of decades ago and it’s not just the hair and fashion that seem dated; it’s the onscreen smiles that often look, by today’s standards, discoloured, yellow or grey. Although there were a few early adopters of bright-white teeth onscreen (thanks to porcelain veneers), the dazzling smiles we associate with today’s film stars, models and even next-door neighbours were rare in years past.

We can thank the introduction of bleaching methods in the early 1990s for the shift to dazzling smiles. More recently, celebrities’ love affairs with blindingly white teeth have led to an explosion of new products on drugstore shelves. These days, most of us know at least one person who has tried some form of bleaching in an effort to get the pearly whites that North Americans now seem to associate with good looks.

There are two basic bleaching methods offered by most dentists, says Laura Tam, professor of restorative dentistry at the University of Toronto. The “tray” method involves the creation of a custom-made mouthguard that the patient takes home, fills with a special bleach solution and wears for a specified period. Depending on the solution, users wear the trays for 30 minutes to an hour, once or twice a day or overnight, for one to four weeks.

The “in office” method uses a higher concentration of bleach — usually five to 10 times stronger than the tray method — and yields results in one session. The dentist applies the bleach to the patient’s teeth and activates it with light or heat.

Although the in-office treatment is the most expensive option, patients are paying for convenience, not efficacy, according to Tam: “You’ll probably get the whitest effect using the tray method at home.”

Over-the-counter options, meanwhile, fall into several broad categories: trays, strips and paint-ons. Tam calls these drugstore products a “one size fits all” approach. Although they often use the same ingredients as those used by dentists and are sometimes comparable in terms of bleach concentration, she says, they’re designed for a “standard” mouth.

In addition, “one size fits all” trays can be bulky and even a bit painful, depending on the shape of your mouth, while whitening strips might not adhere to the entire tooth surface if your teeth aren’t uniform. Paint-on bleaches have been found to be the least effective of the over-the-counter bleach options, according to Tam: “You seem to need a barrier to hold the bleach in place.”

Clinics and spas across Canada offer teeth-whitening services. Because teeth-whitening isn’t regulated (the bleaching agents are not considered drugs by Health Canada), anyone can set up shop to brighten smiles. The Canadian Dental Association doesn’t comment specifically on these clinics but advises Canadians to bleach their teeth under their dentist’s supervision.

Not all dentists offer bleaching services, however. Gary Fortinsky, a dentist in Toronto, says he’s just not interested in purely cosmetic procedures: “It doesn’t tie into my philosophy of dentistry.”

While Fortinsky is not against teeth-bleaching, he sees the phenomenon as simply a marketing-driven phenomenon that relies on people feeling dissatisfied with how they look.

When Fortinsky’s patients express interest in bleaching, he recommends they pick up an over-the-counter method and suggests they first bleach only one row of teeth — top or bottom — so they can see the result in comparison to the unbleached teeth. This method helps prevent the tendency among patients to think nothing has improved — whiteness is almost impossible to assess, he says — and continue bleaching, against both product and CDA recommendations.

Fortinsky has had at least one patient misuse an over-the-counter product, continually bleaching her teeth for three months in an effort to get brighter and whiter: “It’s only going to lighten too much.”

Tam admits there could be issues when perfection-obsessed individuals misuse the products. “There will be certain personalities,” she says, “who will want to overdo it.”

The long-term effects of overbleaching, according to the CDA, may include pitting of teeth and nerve damage.

Tam advises consulting with your dentist. And, she adds, not all tooth discolouration can be treated with bleach. In fact, discoloration can be a sign of something more serious. “You want your teeth to be healthy,” she says, “before you start bleaching.”

People should stop clinging to the idea that whiter teeth automatically make for a more youthful appearance, Fortinsky says. It’s true that 20-somethings generally have nice, bright smiles, but he questions whether it’s natural for older people to have the same teeth as their children.

“Jump ahead 20 or 30 years and it looks like they’re wearing Chiclets,” he says. “[Bleached teeth don’t] match their
appearance.” IE