Teeth whitening is not recommended for people under 18, those who are pregnant or breastfeeding, those with untreated decay or gum disease, exposed root surfaces, severe sensitivity or a peroxide allergy. People with fillings or crowns on their front teeth need separate planning, as a colour mismatch can occur. In most of these cases, treatment is carried out first and whitening is then considered.
Is teeth whitening suitable for everyone?
No, teeth whitening is not suitable for everyone. Whitening is a cosmetic treatment and is planned on healthy teeth and gums. In some situations it should be postponed, and in others it is not recommended at all.
Suitability is decided at the examination. The inside of your mouth is assessed, X-rays are taken if needed and you are asked about your general health. The list below summarises the main situations in which whitening is not recommended or needs particular care.
Some of these situations are not a permanent barrier. Once problems such as decay, gum inflammation or tartar have been treated, whitening can often be planned safely. In situations such as pregnancy and breastfeeding, only the timing changes. The aim is not to prevent whitening but to make sure it is done at the right time and under the right conditions.
List of contraindications
In the following situations, teeth whitening is not recommended or other treatment is needed first.
| Situation | Why is it not recommended? | What is done? |
|---|---|---|
| Under 18 | Cosmetics regulations do not allow use of products above 0.1%; the teeth are still developing | Cosmetic whitening is planned after the age of 18 |
| Pregnancy and breastfeeding | There is not enough data showing it is safe during this time | Postponed until after the birth and breastfeeding |
| Untreated decay | Gel can reach the inside of the tooth through the cavity and cause pain | Decay is treated first |
| Gum disease | Inflamed gums are more prone to irritation | Gum treatment is carried out first |
| Exposed root surface | The root has no enamel, sensitivity increases and the root does not whiten | The area is protected or the method is changed |
| Severe tooth sensitivity | Whitening can increase sensitivity | The cause is investigated first and the sensitivity treated |
| Peroxide allergy | Risk of an allergic reaction | Whitening is not carried out; alternatives are considered |
| Fillings or crowns on front teeth | Restorations do not whiten, so a colour mismatch occurs | Replacement of restorations is planned after whitening |
Why are under-18s and pregnancy treated separately?
Under European Union and Turkish cosmetics regulations, whitening products containing more than 0.1% and up to 6% hydrogen peroxide are not used in people under 18. In addition, young people have a larger pulp chamber and sensitivity may be more pronounced. For details, see our what age can you have teeth whitening page.
It has not been shown that whitening is harmful during pregnancy and breastfeeding; however, there is also not enough data showing it is safe. As whitening is a cosmetic procedure that can wait, it is not recommended during this time. We cover this in detail on our teeth whitening during pregnancy page.
What is done if there is decay or gum disease?
If there is decay or gum disease, these problems need to be treated before whitening. This order matters for both safety and the quality of the result.
- Decay: An untreated cavity can let the gel reach the inside of the tooth and cause severe pain.
- Leaking filling: Gel can seep in around the edge of the filling; the filling is replaced if needed.
- Gum inflammation: Bleeding, swollen gums are more easily affected by the gel. Tartar removal and, if needed, gum treatment are carried out first.
- Tartar: Tartar stops the gel reaching the tooth and makes the result uneven.
For the order of tartar removal and whitening, see our tartar removal and whitening page.
Exposed root surfaces and severe sensitivity
If the root surface is exposed because of gum recession, whitening can increase sensitivity and will not change the colour of the root area. The root surface is covered by cementum rather than enamel, and this tissue responds differently to whitening.
- Exposed root areas can be protected with a barrier.
- With take-home whitening, the tray can be designed so that it does not carry gel to this area.
- If sensitivity is very marked, the cause is investigated first; problems such as wear, cracks or teeth clenching are treated.
For how sensitivity relates to whitening, read our sensitivity after whitening page.
Peroxide allergy and other special situations
Whitening is not carried out in people who are allergic to peroxide or other ingredients of whitening gel. This is rare, but if you have previously had a reaction to similar products, you must mention it.
In some situations whitening is possible, but the result may be limited or special planning may be needed:
- Grey or medication-related (e.g. tetracycline) discolouration responds more slowly and to a limited extent.
- If there are white spots on the teeth, whitening may make them temporarily more noticeable.
- If there is a sore or lesion in the mouth, it is allowed to heal first.
- If you have a condition or take a medicine that causes light sensitivity, take-home whitening may be considered instead of light-activated treatment.
If you have fillings, crowns or veneers on your front teeth
If you have fillings, crowns or veneers on your front teeth, whitening can be carried out, but these restorations will not whiten. While the natural teeth lighten, the restorations stay their old shade and a colour mismatch appears.
In this case the natural teeth are usually whitened first, there is a wait of 1–2 weeks for the colour to settle, and the restorations are then replaced to match the new shade. This is planned at the examination. For details, see our do crowns and fillings whiten page.
What needs to be done before whitening
For whitening to be safe and predictable, some steps need to be completed beforehand.
- An examination and, if needed, X-rays to assess your overall oral health
- Treatment of decay and leaking fillings
- Tartar removal and, if needed, gum treatment
- Investigating the causes of sensitivity and treating them if needed
- Shade planning for restorations on the front teeth
- Recording your starting shade with a shade guide
- Telling the dentist about any medicines you take and any allergies
- Setting realistic expectations
If whitening is not suitable or will not give the expected result, the colour problem can also be addressed with restorative methods such as composite, veneers or crowns. The options are discussed at the examination.
Frequently asked questions
Can someone with gum recession have whitening?
In most cases they can, but exposed root areas should be protected. The root surface does not whiten and sensitivity may increase.
Can teeth with fillings be whitened?
The natural tooth tissue whitens, but the filling does not change colour. Replacement of fillings on the front teeth can be planned after whitening.
Can I have whitening if I have decay?
The decay needs to be treated first. With untreated decay, the gel can reach the inside of the tooth and cause pain.
I take medication – can I have whitening?
Most medicines do not prevent whitening, but you need to mention all the medicines you take at the examination. Suitability is assessed by the dentist.
Can someone who clenches their teeth have whitening?
Usually yes, but if there is enamel wear or cracking, sensitivity may increase. This is assessed at the examination.
Can someone with heart disease or diabetes have whitening?
Chronic conditions that are under control often do not prevent whitening. However, you must mention your medicines and health condition at the examination; the dentist decides on suitability.
Related pages
Can You Have Teeth Whitening During Pregnancy?Why whitening is postponed during pregnancy and breastfeeding, what you can do for your oral health in the meantime, and planning after the birth.
At What Age Can Teeth Be Whitened?The reason for the 18-year age limit, why young people should wait and how whitening is planned in later life.
Is Teeth Whitening Harmful?The effects of dentist-supervised whitening on enamel, gums and sensitivity, and the risks of overuse.
Do Crowns and Fillings Whiten? Shade Matching in WhiteningWhitening gel only works on natural tooth tissue; the right sequence is needed to match the shade of restorations.
Scale and Polish and Whitening: Can They Be Done on the Same Day?The right order for cleaning and whitening, the time in between and choosing a method according to the type of stain.Suitability is decided at an examination. Fill in the form or call us to book an appointment.
Last updated: 2026-11-03 · This page is for general information only and does not replace an examination or diagnosis.