Why Do Whitening Treatments Make Your Teeth Hurt?

If you are purchasing a teeth whitening kit to use at home, your expectations are probably quite basic. You expect your teeth to be whiter than they were before you used the product — no more, no less. While you might be sceptical that the product will deliver the results its marketing promises, you still expect a noticeable difference to the appearance of your smile. What you don't expect is pain. 

A Warning

It might seem strange that your teeth whitening efforts lead to immediate pain. This pain might be focused on a single tooth or multiple teeth. In any event, pain is a warning that something's wrong, and you must immediately discontinue use of the whitening kit. But teeth whitening is such a simple, common process, so why does it hurt?

Your Tooth's Nerve

The only part of a tooth that is capable of registering pain (or any sensation, for that matter) is its nerve (also known as the dental pulp). This nerve is located at the centre of the tooth, safely contained within the pulp chamber. The chamber is encased in cementum (which makes up the bulk of the tooth's structure), and this cementum is coated in dental enamel. Teeth whitening treatments should only be lightening the dental enamel. Since enamel doesn't have any nerves itself, it can't actually register pain. However, it's not your enamel that is being irritated.

Gaps in Your Protection

Untreated cavities and decay can leave gaps in your protective dental enamel. This allows the whitening treatment's active ingredient (typically carbamide peroxide) to come into contact with your cementum. Dental cementum contains multiple tiny canals leading from the surface of the cementum to the pulp chamber. It is possible that trace amounts of carbamide peroxide are reaching your dental pulp, which reacts accordingly. Does this mean you should forget about trying to whiten your teeth?

Dental Restorations

Cavities and decay must be addressed for teeth whitening to be effective, which should also eliminate the pain caused by the process. You must see your dentist to have these issues treated before your teeth can be efficiently whitened. In the event that you need dental restorations to be added to your teeth (such as a crown, an onlay or inlay, or even a large filling), whitening your teeth will require a more specific approach.

Desired Shade of White

When receiving a restoration, inform your dentist that you intend to whiten your teeth. This allows the restoration to be applied in the desired shade of white. Your natural teeth can then be whitened to match the restoration, and they must be maintained at this shade to prevent a colour mismatch. Restorations (whether ceramic or resin) will not be responsive to whitening treatments, which is why they set the benchmark for the overall shade of your smile.

Pain is not a standard part of whitening your teeth. Any pain experienced during your whitening efforts means you need to see your dentist, who can correct your issue while also whitening your teeth with greater speed and efficiency than any at-home kit. Contact a dentist who offers teeth whitening services to learn more.