There are the usual suspects when it comes to why your teeth can feel uncomfortably sensitive after whitening. You might be using too much whitening gel, causing the product to leak from the applicator trays, where it burns your gums. You might also have untreated dental decay, creating a tiny pathway to the tooth's nerve, which is then irritated by contact with the whitening agent. But perhaps neither of these scenarios applies to you. So why do your teeth whitening efforts inevitably lead to sensitive teeth?
No Universal Response
Although post-whitening sensitivity is common, there's no universal response to the process. Some people may experience no sensitivity, whereas others may find the experience to be extremely uncomfortable. In the absence of any clear reasons for the sensitivity (such as the previously mentioned untreated tooth decay, or using too much of the product), your sensitivity can be a mystery. It could be that with regular use, the whitening gel is slowly altering the proteins in your teeth.
The Proteins in Your Teeth
An American study has found that repeated exposure to hydrogen peroxide (the active ingredient in many teeth whitening gels) can penetrate both your tooth's outer layer of enamel, as well as its inner layer of dentin. Your dentin is rich in proteins such as collagen, and your teeth whitening may be affecting the protein composition of your dentin. Although any loss is minimal, tiny amounts of your dentin may be breaking away and being absorbed back into your body—a process triggered by whitening. The structural strength of the tooth may not necessarily be affected, but it can cause unpleasant levels of sensitivity.
Remineralising Your Teeth
This sensitivity can largely be sidestepped by immediately remineralising your teeth after whitening—with a fluoride treatment generally being appropriate for this. This helps to fortify your teeth, offsetting any protein loss. However, it's unwise to simply treat your teeth with fluoride, as excessive use of fluoride has drawbacks for your teeth. It's wise to consult your dentist before beginning any fluoride treatment.
Help From Your Dentist
Of course, if you need to consult your dentist, you may wish to have them whiten your teeth. Any remineralisation measures needed to counteract your sensitivity can be performed immediately, and unlike home treatments, your teeth whitening is usually achieved in a single session, reducing the time your teeth will be exposed to the whitening agent.
Uncomfortable sensitivity after whitening is still possible for those whose teeth are perfectly healthy, and who might follow the precise application instructions for the whitening product. It can easily be that the proteins in your teeth are being adversely affected by your efforts, meaning having a dentist whiten your teeth might well be the best way forward.
For more information about teeth whitening, contact a local dentist.