Teeth whitening can be an effective way to brighten the appearance of natural teeth, but, like any dental treatment, it can sometimes cause temporary side effects.
The most commonly reported problems are tooth sensitivity and irritation of the gums. Whitening results can also vary considerably from person to person, so it is important to have realistic expectations before beginning treatment.
Having your teeth and gums checked by a dentist before whitening is recommended, particularly if you already experience sensitivity, have exposed tooth roots, gum problems, tooth decay or extensive dental restorations.
Tooth Sensitivity During Whitening
Temporary tooth sensitivity is one of the most common side effects associated with peroxide-based teeth whitening.
You may notice a short, sharp sensation when drinking something cold or eating certain foods. For most people, whitening-related sensitivity is temporary and improves after treatment has stopped.
If you already have sensitive teeth, it is particularly important to discuss whitening with your dentist before beginning treatment.
How to Reduce Whitening Sensitivity
There are several steps that may help reduce sensitivity before and during a whitening programme:
- Have your teeth examined before whitening. A dentist can check for decay, gum problems, exposed roots, cracked teeth or other conditions that could contribute to sensitivity.
- Treat existing dental problems first. Whitening shouldn’t be used as a substitute for addressing an underlying dental problem.
- Consider a sensitive toothpaste. Toothpastes containing ingredients such as potassium nitrate, potassium citrate or stannous fluoride may help manage sensitive teeth.
- Ask your dentist about desensitising products. Depending on your circumstances, your dentist may recommend a specific desensitising treatment before or during whitening.
- Don’t assume stronger is better. Whitening gels come in different concentrations and formulations. Always use a product appropriate for you and follow its specific instructions.
- Don’t exceed the recommended treatment time. Leaving whitening gel on for longer than instructed isn’t a shortcut to better results and may increase irritation or sensitivity.
- Consider spacing treatments if advised. If sensitivity develops, a dental professional may recommend using whitening gel less frequently or on alternate days. Leeds Teaching Hospitals, for example, advises that people experiencing significant sensitivity may be instructed to move to alternate-night treatment.
If sensitivity becomes severe, persists after whitening has stopped or affects only one particular tooth, speak to your dentist. Persistent sensitivity can sometimes have another dental cause that needs investigating.
Gum Irritation
Whitening gel can also temporarily irritate the gums, particularly when peroxide-containing gel comes into prolonged contact with soft tissue.
This can happen when too much gel is placed into the whitening tray, causing excess product to squeeze over the edge and onto the gums. Poorly fitting trays can also increase the likelihood of gel reaching the surrounding tissue.
The solution isn’t to completely fill your whitening trays with gel.
Use only the amount recommended in the instructions supplied with your whitening system. If excess gel reaches the gums after inserting the tray, remove it as directed rather than leaving it against the gum tissue.
If your gums become painful or significantly irritated, stop whitening and seek advice from your dentist.
What If My Whitening Results Are Disappointing?
Teeth whitening isn’t an exact science, and results vary from person to person.
Some teeth respond relatively quickly, while others may require a longer professionally advised treatment period. The starting colour of your teeth, the type of discolouration and your individual tooth structure can all influence the final result.
It’s therefore important not to assume that using additional gel or increasing the treatment time will necessarily produce whiter teeth.
Sometimes a whitening programme may simply need more time. In other cases, the particular type of discolouration may not respond as strongly to whitening.
Leeds Teaching Hospitals notes that although whitening can lighten teeth, it may not produce a complete colour change and additional treatment can sometimes be required to achieve the desired result.
Know When to Stop
Whiter isn’t always better.
Once your teeth have reached the desired shade, or you notice they are no longer becoming lighter, don’t continue applying more whitening gel simply in an attempt to achieve an unnaturally white result.
Following the recommended treatment protocol is more important than trying to accelerate the process.
Remember: Restorations Won’t Whiten Like Natural Teeth
Another potential reason for an uneven result is existing dental work.
Whitening treatments are intended to change the shade of natural teeth. Existing restorations such as:
- Crowns
- Veneers
- Composite bonding
- Tooth-coloured fillings
- Dental implants
will not predictably become lighter in the same way.
This means that previously colour-matched dental work may appear darker after the surrounding natural teeth have been whitened. nhs.uk
If you have visible restorations, particularly on your front teeth, discuss this with your dentist before starting whitening.
Getting the Best from Your Teeth Whitening Treatment
Successful whitening isn’t simply about choosing the strongest gel available. Correct application, an appropriate whitening formulation, well-fitting trays and following the recommended treatment time are all important.
For the best experience:
- Have your teeth and gums checked before whitening
- Follow the instructions for your specific whitening gel
- Use only the recommended amount of gel
- Avoid extending treatment times
- Keep excess gel away from your gums
- Don’t ignore persistent sensitivity
- Remember that whitening results vary between individuals
- Speak to your dentist if you experience significant discomfort or aren’t achieving the expected result
Most importantly, don’t try to compensate for disappointing results by simply using more gel or whitening for longer. If your teeth aren’t responding as expected, a dentist can help determine why and advise whether continuing treatment is appropriate.
When Should You Speak to Your Dentist?
Stop treatment and seek professional advice if you experience severe or persistent sensitivity, significant gum irritation, swelling, ongoing pain or another reaction that concerns you.
Temporary sensitivity and mild gum irritation can occur with whitening, but symptoms that persist or become more severe shouldn’t simply be ignored