"The patients whose teeth start out the worst can end up 11 or 12 shades lighter, while someone with lighter teeth will see more subtle results," says Dr. Golub-Evans. But if your teeth are deeply stained, skip the over-the-counter products and go straight to professional, in-office whitening treatments. "Our equipment can penetrate your tooth's surface more deeply and access stains that drugstore products aren't strong enough to reach," he says.


Not sure what color your teeth are? Head to a mirror and hold a sheet of pure white paper next to your smile to see whether your teeth seem more yellow, brown, gray, or blue in comparison. Yellow-based stains are just extrinsic — meaning the stains are caused by debris lodged into the pores on the outside of your tooth enamel — making them the easiest kinds of stains to lighten with bleaching. Brown-based stains are a mix of extrinsic and intrinsic, so you can still expect to go five or six shades lighter.


Alas, the news isn't quite so good if your teeth are gray, which is a sign of internal staining from antibiotic use, too much fluoride, or decay. But all is not lost: "Even in extreme cases of discoloration from antibiotic use, we have seen amazing whitening results," says Barry Kramer, DDS, founder of Aesthetic Bronx Cosmetic Dentistry in New York. "The process takes longer, but results are encouraging." If your teeth have a bluish hue, however, it's time to step away from the whitening strips: "That's a sign of over-whitening and is more difficult to correct," Dr. Kramer notes.


"All whitening treatments use the same [carbamide or hydrogen] peroxide, no matter what you pay," Dr. Golub-Evans explains. "The more expensive procedures you can have done in a dentist's office just offer a more concentrated dose, which means the results will last longer — usually three to five years." But at $20 to $50 a box, whitening strips offer a more affordable option. Dr. Golub-Evans is a fan of Crest 3D White 2 Hour Express Whitestrips, which includes the same enamel-safe whitening agent dentists use. Four treatments cost about $50! Plus, the strips work in just two hours and deliver up to three months of a whiter smile. Daily Glow editors like the no-slip strips that allow you to drink water while whitening.


"Professional whitening is the most expensive option, but it works quickly, and the results last for years," says Dr. Golub-Evans. Of course, you always have at-home options that take anywhere from 10 minutes to an hour for a treatment. But brightening your smile can be as easy as adding a whitening toothpaste to your routine. A little daily maintenance can make a big difference without requiring you to set aside special whitening time. Try Colgate Total Advanced Whitening Gel that does all the work of a cavity-fighting toothpaste while also offering whitening benefits.



"Strips are the best over-the-counter option for this reason because they keep the peroxide localized on your teeth," Dr. Golub-Evans explains, noting that you can use the strips every other day instead of daily to reduce sensitivity and get the same quality results.

Another way to reduce your sensitivity is to carefully target the treatment. The Listerine Whitening Pen allows you to paint bleaching agents carefully on stained areas — you can even focus on specific teeth rather than treating your entire mouth.

"In-office, I find patients do best with the Zoom! Chairside Whitening System (average cost $500). It uses a cool light that minimizes sensitivity. We also put a waxy mask over the rest of your mouth to prevent peroxide from getting on anything with nerve endings."


"The quicker you can get those substances off your teeth, the less staining you'll see," Dr. Golub-Evans explains. "Studies show that most people who get their teeth professionally whitened don't have to redo it for three to five years, even without making major lifestyle modifications." You can help preserve your results further by adding more teeth-cleaning foods, like crunchy carrots, celery, and lettuce, to your diet. "When you're at a cocktail party, choose the veggie platter over the cheese and crackers, especially if you're drinking red wine," Dr. Golub-Evans advises. "That sticky combination creates instant plaque, which is what gives you that stained red-wine mouth."



"Since the inception of take-home whitening in the 1980s, there have been no serious documented side effects," notes Dr. Kramer. But keep in mind that most studies are done by the product manufacturers; a June 2009 evidence review concluded that independent, long-term clinical trials are needed to fill in data gaps. We do know that overuse or misuse of whitening treatments (both over-the-counter and in-office) can cause benign sensitivity (meaning you feel pain, but teeth won't be damaged), irritation, and blistering of the gums, and in rare instances, photosensitivity to light.

"Don't do this the day before a big event if you don't know how you'll react," says Dr. Kramer. "I tell brides to schedule their teeth whitening six to eight weeks before the wedding, just in case of side effects like these." And be sure to tell your dentist about any medications you're taking, as certain drugs may increase the risk for photosensitivity.