According to a study published in The Journal of the American Dental Association, mild tooth sensitivity can be expected in approximately half of patients who undergo home whitening treatments. Many people experience sensitivity after bleaching their teeth for a few days. The stinging or aching sensation you’re feeling is a result of overexposure to bleach.
“Temporary sensitivity results from the nerves being stimulated by the procedure. To control this, brushwith a toothpaste that contains both fluoride and potassium nitrate before and after whitening,” says Chicago cosmetic dentist Margaret Mitchell, DDS. Sensitivity can be difficult to prevent as there is no set standard on how long is too long when it comes to bleaching.
To minimize the risk, always follow the directions as they appear on the box. Says Las Vegas cosmetic dentist Patrick Simone, DDS, “When it comes to take-home bleaching trays, patients should not exceed three hours a day for up to 30 days. Sensitivity can arise when this time limit is exceeded. There is no reason to exceed the time limit because bleach is most effective for up to three hours.” After that, saliva dilutes the formulation, making the bleach’s whitening power less effective and irritating the nerve endings inside your teeth.
Any discomfort should go away about two days after you stop bleaching. “Bleach opens the tubules, or pores, in enamel and removes the stain. When you stop bleaching, it takes about 48 hours for your teeth to absorb minerals in your saliva and reharden,” says New York cosmetic dentist Irene Grafman, DDS. To speed up the remineralization process, look for mouthwashes, toothpastes and even gums that contain calcium as an active ingredient—calcium naturally hardens weak enamel by plugging the pores responsible for the painful movement of fluid near the nerves of your teeth. “Since sensitivity is caused from inflammation of the tooth nerve, anti-inflammatories like ibuprofen will help alleviate discomfort,” explains Boston cosmetic dentist Andrew Wiemeyer, DMD.