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5 things to know about teeth whitening


A white and winning smile can be bought — but what should you know before investing in your (would be) pearly whites? We asked Ron Perry, DMD, MS, clinical professor, and director of the Gavel Center for Restorative Research at Tufts University School of Dental Medicine for advice about whitening.

1 Concentration is key

Across all methods of teeth whitening — whether it be an at-home kit or a procedure done by pros — results are determined by concentration of bleach, and time. While most over-the-counter products — think white strips and mouth rinses — do work, they take longer and require consistency to see significant results. “Most people want the instant scratch ticket, where they get the whitest teeth right away,” said Dr. Perry. “However, higher concentrations may lead to post-op sensitivity.”


2 Remember the rebound

Your teeth might look blindingly white when you step out of your doctor’s office, but it’s an effect that wears off. This rebound period lasts about a week or so, when your teeth begin to reveal their lighter shade. “They look whiter because they’re dehydrated,” said Dr. Perry. “Everything levels off after about two weeks time. That’s when you have the shade you’ll ultimately be.”

3 Take a picture, it lasts longer

If you decide to do an at-home whitening kit, snap a photo of your smile in daylight before application and compare it to a similarly staged photo a week later. You’ll get a better idea of where you’ve moved on the shade scale and determine whether a second treatment is needed. “Sometimes people bleach at home and they don’t think anything changes because they can’t remember what they looked like prior,” said Dr. Perry. If you go to a pro, they’ll hand you a “shade tab,” so you can see the before and after contrast.


4 You can overdo it

If you’ve developed a regular ritual of whitening strips, toothpaste, and mouthwash, you want to be honest with a professional before going for a clinical whitening treatment. Over-bleaching can harm teeth. “Normally they can still go right into it,” he said, “but if you have been bleaching for a year or so, you’re probably not a good candidate.”

5 It’s OK to be sensitive

If you think you have sensitive teeth — and trust us, you’ll know — don’t fret. A consultation with a professional can present other smile-
improving options. “They can do composite fillings or they might be a good candidate for veneers or a crown and bridge,” Dr. Perry explained. “Or sometimes, it could just be a malalignment that needs to be fixed, where teeth look darker than they really are because they’re just seeing shadows.”


Rachel Raczka can be reached at rachel.raczka@globe.com