A) Common problems.
By far, the two most common side effects people experience when using a whitening strip product (like Crest Whitestrips®) are: 1) Tooth sensitivity and 2) Gum irritation. This page outlines remedies for both of these complications. A less frequent side effect is throat irritation/sore throat.
b) Side effect avoidance.
You can minimize your risk for side effects, or get them under control more quickly once they start to appear, by following some basic guidelines. The lower portion of this page explains how.
1) Tooth sensitivity.
Studies suggest that between 1/3 and 1/2 of all people who use Crest Whitestrips® will experience some degree of tooth sensitivity. This is on par with that level typically reported for other peroxide-based whitening methods.
a) Why does it occur?
The cause of the sensitivity is no doubt multifactorial. But one major aspect has to do with irritation (inflammation) of the tooth's nerve by the strip's peroxide whitener.
In general, the more concentrated the whitener, the more likely it is that this effect will occur. (So, if you're searching for the "strongest" or "quickest working" strip, you may be setting yourself up for a fall.)
b) What's the pain like?
In most cases, the sensitivity that's noticed is a heightened reaction of your teeth to hot and cold items, such as foods and beverages. Dentists call this "thermal sensitivity."
How much pain can you expect?
Since strips whitening typically involves the use of a relatively low concentration whitener, the sensitivity they cause usually comes on gradually. It may increase with each treatment, or just be noticeable for those first few hours following a bleaching session.
Since the sensitivity is usually relatively minor, and setting it off fairly easy to avoid, it typically doesn't cause great disruption in a person's life. Or even interfere with their bleaching schedule.
1) Some improvement should occur naturally.
In the majority of cases, a person should notice that their thermal sensitivity begins to fade, a little each day, once they have completed their bleaching treatments.
Performing whitening sessions less frequently or using a lower concentration product (such as Whitestrips® Gentle Routine) can help to speed this process along. - More information.
2) Try using desensitizing toothpaste.
You may be able to control the level of sensitivity that you experience by using an over-the-counter anti-sensitivity (desensitizing) toothpaste.
Using desensitizing toothpaste, before or after problems occur, can help.
Many manufacturers make an anti-sensitivity version of their regular paste. These products are often labeled with the phrase "toothpaste for sensitive teeth." Their active ingredient is frequently potassium nitrate or fluoride.
Relief may take some time. - The idea is that you use the toothpaste in place of your regular one, for some days and weeks, as it gradually produces its effect.
(Prescription-strength fluoride toothpaste or gel prescribed or dispensed by your dentist can also be used in a similar fashion.)
3) Preventing tooth sensitivity.
As a way of helping their patients reduce their risk for experiencing thermal irritation, many dentists recommend that they begin using a desensitizing toothpaste two weeks prior to initiating the use of their whitening strips.
2) Gum irritation.
Studies suggest that between 1/3 and 1/2 of all people who use Whitestrips® will notice some degree of gum tissue irritation.
Gum irritation is caused by the caustic nature of the peroxide found in a strip's whitener. In general, the higher its concentration, the greater the likelihood that this side effect will be noticed. (Once again, a reason why the "strongest" or "quickest working" type of strip doesn't likely make the best choice.)
The cause of whitening strip gum irritation.
1) The fit of the strips is part of the problem.
Unlike the scalloped shape of a person's gum line, the edges of a whitening strip are relatively straight.