Whitening May Cause Short-Term Tooth Sensitivity

A word of caution to those who want to brighten their smile by whitening their teeth. A study in the Journal of the American Dental Association reveals one in two people experience temporary tooth sensitivity as a result of home whitening treatment. Patients with receding gums appear most likely to experience such tooth sensitivity.

The American Dental Association (ADA) advises patients to consult with their dentists to determine the most appropriate whitening treatment. This is especially important for patients with many fillings, crowns and extremely dark stains.

"The good news is tooth sensitivity tends to decrease as whitening treatment progresses and is not likely to prevent patients from successfully completing the full course of home whitening treatment," said researcher Michael Jorgensen, DDS, associate professor of clinical dentistry at the University of Southern California (USC) School of Dentistry in Los Angeles.

During the four-week study of 100 patients at the Naval Medical Center in San Diego, researchers found 61 patients reported varying degrees of tooth sensitivity during the first week of treatment. By the end of the study, only seven patients reported any tooth sensitivity.

In the study, researchers from the USC School of Dentistry and the Naval Medical Center fitted 100 patients with a custom mouth tray and randomly assigned 50 patients to receive a 15 percent carbamide peroxide whitening gel while the other 50 patients were given a placebo gel.

Patients were told to fill the tray with the appropriate amount of gel and wear it for 3-4 hours per day for four weeks. Researchers then evaluated tooth sensitivity by interviewing each patient on a weekly basis, recording responses on a scale of 0-3, where 0 indicated no change and three indicated sensitivity severe enough to cause patients to avoid many foods and cause major interference with tooth function.

After one week of home whitening treatment, 54 percent of the patients in the carbamide peroxide group reported mild sensitivity; eight percent reported moderate sensitivity and four percent reported severe sensitivity. Interestingly, the same percentage of patients using the placebo gel (54 percent) also complained of mild tooth sensitivity.

At the end of the study, only eight percent of patients in the carbamide peroxide group and six percent in the placebo group reported mild tooth sensitivity. All others reported no sensitivity. "Patients considering home whitening should be informed of its potential risks and benefits," Dr. Jorgensen advises. "Dentist-supervised home-use whitening systems have been shown to be safe and effective, resulting in only mild, temporary changes in gum and dental pulp tissues."