The Scientist: Dr. Michael Gulizio, a prosthodontist and professor at NYU School of Dentistry who practices at Core Smiles in Midtown Manhattan.

The Answer: The pain associated with teeth whitening is typically due to oxygen molecules that find their way towards the tooth’s pulp tissue, which has blood vessels and nerve endings. Teeth whitening products work by releasing a molecule of oxygen into the tooth which will ultimately drive out staining particles. If the oxygen molecule gets too close to the pulp tissue, it creates a “bubble” of oxygen, which stimulates the nerve ending in the tooth and causes pain.

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You should expect slight to moderate sensitivity when whitening teeth. As long as whitening is completed in a controlled environment like your dentist’s office, the sensitivity should never become excruciatingly painful. Most of the time, any pain lasts for 24 hours at most. If you have more than 2 or 3 days of pain following a whitening procedure, you should contact your doctor.

If you’re getting your whitening done at a doctor’s office, they will likely apply a desensitizing agent to combat sensitivity; at Core Smiles, we apply a desensitizing agent every 10 minutes during the procedure. Another trick to combat sensitivity is to prevent it altogether. Whether you’re whitening in an office or at home, take an Ibuprofen one hour prior to whitening and again six hours afterwards.

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