You Can't Really Bleach Your Teeth White, and Other Things You Didn't Know About Professional Teeth Whitening (2024)

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The desire for and pursuit of whiter teeth is nothing new. Even though it's perfectly natural to have a smile that gets a bit dingy or stained with age, less-yellow-is-more has been the aesthetic attitude for centuries. And for the last century, at least, the basic concept of how to effectively bleach one's teeth — typically a combination of a peroxide compound and light — has changed very little other than an increase in scientific sophistication and ease of application. But despite its ubiquity, there's still a lot of mystery and misconception surrounding the professional tooth-whitening treatments performed in dentists' offices.

Speaking from personal experience, my mind was pretty much blown when I underwent an in-office whitening treatment a few years ago. I had no idea what to expect, and I ended up surprised by many aspects of it — sometimes in ways that delighted me and sometimes in ways that disappointed me. So I'm here to help you be better prepared than I was for the whitening appointment you're thinking of making. Because, trust me — there are a few things you didn't know about getting whiter teeth at the dentist's office.

"Generally, in-office whitening treatments are highly effective, take as little as one session, and are well-accepted by most patients," says Dallas-based dentist Amanda Lewis, DMD. "If somebody has questions about whitening, they should speak with their dentist." But if, like me, you didn't even realize you have questions about whitening, I went ahead and got a few answers for you before you call for a consultation.

Meet the experts

Amanda Lewis, DMD, is a dentist in Dallas, Texas, and the founder of the dental brand Lewie.
Marc Lowenberg, DDS, is a cosmetic dentist with Lowenberg, Lituchy & Kantorin New York City.
Wesam Shafee, DMD, is a cosmetic dentist in Paramus, New Jersey.

Not everyone is a good candidate for professional teeth whitening

Unfortunately, although many people want whiter teeth, the formulas and techniques used in professional tooth-whitening treatments eliminate some folks from being ideal patients.

"If somebody has veneers, root canals, caps, or infected teeth, their teeth will not whiten properly," says New Jersey-based cosmetic dentist Wesam Shafee, DMD, whose practice always performs a preliminary exam to establish whether the patient is an appropriate candidate for in-office whitening. "Additionally, the exam would allow us to determine if the patient has exposed roots. Patients who have exposed roots would experience severe discomfort during whitening."

Though you should always get a consultation with your dentist before sitting down for a whitening treatment, you may not need an exam to know If you're not the right person for the process. "If you have extreme sensitivity, I don’t recommend it," says New York City-based cosmetic dentist Marc Lowenberg, DDS.

You may feel some pain, even if you have healthy natural teeth

Discomfort, even pain, is not unheard of among patients undergoing — or who have recently undergone — an in-office tooth-whitening treatment. This is typically due to the procedure desiccating the teeth, according to Dr. Lewis.

"When you bleach, you can cause some internal dryness, and that discomfort usually lasts 24 to 48 hours. The strength of the material and the amount of contact time are the main players in that game," she says, adding that some whitening systems have built-in desensitizers that can help prevent or lessen discomfort.

If you have an appointment coming up and you have a history of moderate sensitivity, you can prepare by switching to a desensitizing toothpaste. "My recommendation for people with sensitive teeth would be to first use Sensodyne for six weeks prior to getting their teethwhitened," Dr. Lowenberg tells Allure.

Sensodyne Repair & Protect Whitening Toothpaste

"Some people experience 'zingers' after whiteningprocedures, which is a jolt of sensitivity," Dr. Lowenberg adds. "We recommend an anti-inflammatory like Advil to counteract this sensitivity."

Not all in-office tooth-whitening treatments are the same

As Dr. Lewis mentioned, the strength, time, and inclusion of a desensitizer are all variables in a professional tooth-whitening treatment. Furthermore, the kind of light used may vary.

"There are three types of in-officewhiteninglights: UV, LED, and halogen, depending on the manufacturer," says Dr. Lowenberg. "The one that causes the least amount of sensitivity is the LED light," and it's also the most commonly used light in both in-office and at-home tooth-whitening systems (though many at-home systems do not come with lights).

Some dentists' offices also offer laser-based teeth whitening. "When we have laser light technology, that is usually a little higher quality than an LED," says Dr. Lewis. "It can affect the immediate boost of whiteness that a person will get."

But ultimately, the treatments rely on the bleaching chemicals that the lights and lasers help activate (though they are capable of whitening teeth without adding illumination). "Most in office tooth-whitening procedures use similar ingredients," says Dr. Shafee, who says the gels or pastes applied to the teeth typically feature hydrogen peroxide or carbamide peroxide.

You won't get truly white teeth — and that's a good thing

When you're at your appointment, your dentist may show you a shade guide that will give you a sense of the shade your teeth are now versus brighter shades you may want to aim for. If you want to go as white as possible but worry about looking like Ross did when he got his teeth bleached on that one episode of Friends, worry not — you won't startle people with the phosphorescence of your teeth.

Neither Dr. Lewis nor Dr. Shafee try to talk their patients out of going for the brightest shade. "Teeth have varying shades of thickness and densities of the material that make them up," says Dr. Lewis. "What tends to happen is that patients think they want something that is white, when what they really mean is they want a uniformness in opacity that is not necessarily present in a natural tooth."

Dr. Lowenberg explains that, because different people's teeth react differently to whitening, you can't expect to go 20 shades lighter, nor can you pick an exact shade. "People have unrealistic expectations of how white their teeth can get fromwhitening," he says. "Some patients come in and want their teeth to look like white T-shirts. That’s never going to happen."

But the good news is, even if you do achieve a significantly lighter shade, it won't look fake as long as your teeth themselves aren't fake. "When whitening natural teeth, in my opinion, they will always look natural no matter how white they get," Dr. Shafee says.

Your whitening won't last forever

In fact, it probably won't even last a year. This was the biggest surprise for me — when, a year after my treatment, I felt like I was back to coffee-compromised square one.

"Teeth whitening is not a once-in-a-lifetime thing," says Dr. Shafee. "Drinking and eating certain kinds of drinks and food like wine, coffee, red sauce, curry, and more, can discolor your teeth." Dr. Lewis adds that herbal teas are among the biggest culprits when it comes to un-whitening teeth.

But you shouldn't whiten too often

To achieve and maintain your whitening results, you shouldn't need to get a treatment more than twice a year. More than that, and you risk some negative side effects.

"Professionalwhiteningmore often than twice a year is not necessary and can dry out enamel," says Dr. Lowenberg. "That drying out of enamel from over-whiteningwill make teeth sensitive and chalky-looking."

Even if it's your first time getting your teeth whitened at the dentist's office, you should be aware of potential issues. For example, Dr. Lowenberg says, if thewhiteninggel is left on too long, it can cause irritation to the nerves or teeth, or inflammation to the gums.

Both Dr. Lewis and Dr. Shafee say this is very unlikely, however, when performed by a qualified dentist, because they take the correct, thorough precautions. "If the gums are healthy and there are no nerves that are exposed, office whitening is very safe and would not cause any structural damage,"says Dr. Shafee.

You can achieve similar results at home — but not quite the same

Ultimately, for the brightest, fastest, and long-lasting results, in-office whitening is the gold standard. However, achieving similar results with at-home products is not out of the realm of possibility. But depending on a number of factors, it may take longer, have less even results, or lose brightness sooner.

"If you use the same ingredients used in the dental office, you will achieve very similar results," says Dr. Shafee, adding that the power of the lights used during office treatments tends to speed the whitening along more than what at-home systems and products can.

While the ingredients may be the same in an at-home product, they won't be present at the same strength. "Results from over-the-counter products do not last nearly as long as in-officewhiteningbecause they use a lesser concentration of hydrogen peroxide," Dr. Lowenberg explains.