Teeth whitening in Brussels: in-chair or at home with trays
Teeth whitening lightens the natural shade of your teeth with a peroxide-based gel, applied either at the practice in a single session of around 60 to 90 minutes, or at home with custom-made trays over one to two weeks. At the practice in Etterbeek, Dr Denis Catarau first checks that your teeth and gums are healthy enough for it.
Written and reviewed by Dr Denis Catarau, dentist in EtterbeekUpdated: October 2026
The practice
Detaille dental practice
- Rue des Champs 64, 1040 Etterbeek (Brussels)
- Monday to Friday, 9:00 to 18:00
- French, Romanian, Russian
- +32 2 217 11 18
- In-chair
- 1 session of 60-90 min
- Home trays
- 1-2 weeks at home
- Sensitivity
- common, temporary (1-3 days)
- Results
- 1 to 3 years, depending on habits
How does teeth whitening work?
Whitening gel contains hydrogen peroxide, or carbamide peroxide, which releases it. It passes through the enamel and breaks down the pigments in the dentine that give teeth their colour. It does not remove enamel or sand the tooth down.
Whitening is not the same as a scale and polish. A professional clean removes surface stains from coffee, tea or smoking, and is sometimes enough for a brighter smile. Whitening changes the shade of the tooth itself. Yellowish teeth usually respond better than greyish ones, and some deep discolouration, such as tetracycline staining, is harder to lighten.
In-chair or home trays: which should you choose?
Both methods work well when they are properly indicated. The choice depends mainly on your schedule, how sensitive your teeth are and the result you are after; the two can also be combined.
- In-chair: the gums are protected with a barrier, a stronger gel is applied in several rounds, and you see the result the same day
- Home trays: custom-made trays with a milder gel, worn daily as instructed for 1 to 2 weeks; a more gradual result and often less sensitivity
- You keep the trays and can use them later for short top-ups
What EU rules say
In the European Union, stronger whitening products are reserved for dentists: treatment must be carried out, or at least started, by a dentist after an oral examination, and it is not intended for under-18s. Products sold over the counter are limited to very low concentrations, which explains why their results are often modest.
Sensitivity and when whitening is not advised
Sensitivity to cold or brief twinges are common during treatment and for a few days afterwards; they usually settle within one to three days. A toothpaste for sensitive teeth or a desensitising gel helps. In some situations whitening is not advised, or is postponed.
- Under 18
- Pregnancy and breastfeeding, as a precaution
- Untreated decay or inflamed gums, which are treated first
- Exposed roots or teeth that are already very sensitive
- Known allergy to peroxide
Crowns, veneers and fillings do not whiten
The gel only works on natural teeth. Crowns, veneers and composite fillings keep their colour: after whitening, they may look darker than the teeth around them and sometimes need replacing for an even shade. If you are planning veneers or composite bonding, whitening comes first, followed by a wait of about two weeks for the shade to settle.
How long do the results last?
Results generally last one to three years, depending on your habits. Coffee, tea, red wine and smoking bring the old shade back sooner. For 48 hours after treatment, it is best to avoid strongly coloured food and drink. Regular cleaning and, if needed, a short top-up with your trays help the result last longer.
How whitening works, step by step
- 1
Consultation and assessment
An examination of your teeth and gums, a record of your starting shade and photos. Contraindications are checked, along with any visible restorations that will not whiten.
- 2
Preliminary care
If needed, a scale and polish and treatment of any decay or gum problems before starting. For home whitening, impressions for your trays are taken at this stage.
- 3
Whitening
In the chair, your gums are protected and the gel is applied in several rounds. For home whitening, you receive your trays and clear instructions.
- 4
Review and advice
Your new shade is compared with the starting one. You get advice on limiting sensitivity and keeping your result.
Whitening costs and reimbursement
Whitening is a cosmetic treatment. The cost depends on the technique (in-chair, home trays or both) and on any care needed beforehand.
- INAMI reimbursement
- none (cosmetic treatment)
- Mutuelle or dental insurance
- rarely, depending on the policy
- Scale and polish beforehand
- listed in the INAMI fee schedule, partly reimbursed
The cost of whitening at the practice is given in a quote after consultation. Dr Catarau is a non-contracted (non-conventionné) dentist: his fees may be higher than the INAMI agreed rates.
Frequently asked questions about teeth whitening
Another question? The practice answers by phone, Monday to Friday.
Does teeth whitening damage enamel?
No, when it is supervised by a dentist and uses suitable products, whitening does not damage enamel: it breaks down pigments without removing any tooth. The usual side effects are temporary sensitivity and sometimes mild gum irritation, which settle within a few days. Abrasive or misused products, on the other hand, can wear enamel away.
How much does teeth whitening cost?
The cost of whitening depends on the technique (in-chair, home trays or a combination) and on any care needed first, such as a scale and polish. It is not reimbursed by INAMI and rarely by mutuelles. At the practice in Etterbeek, you receive a quote after the consultation.
Does teeth whitening hurt?
Whitening is not painful, but it often causes sensitivity to cold or brief twinges for one to three days. This is more common with in-chair whitening. A toothpaste for sensitive teeth, a desensitising gel or spacing the sessions further apart reduces it noticeably.
How long does teeth whitening last?
Teeth whitening usually lasts one to three years. The shade returns sooner if you regularly drink coffee, tea or red wine, or if you smoke. Regular cleaning and a short top-up with your trays, for example once a year, help the result last longer.
In-chair or home whitening: which works better?
Both work: in-chair whitening gives a visible result in a single session, while home trays get there over one to two weeks, more gradually and often with less sensitivity. The final result is comparable, and the two methods can also be combined.
Can crowns or veneers be whitened?
No, crowns, veneers and composite fillings do not whiten: only natural enamel responds to the gel. After whitening, these restorations may look darker and sometimes need redoing. That is why whitening is done first, and any new restorations are then made to match the new shade.
Do whitening kits bought online work?
Kits sold over the counter in the European Union are limited to very low peroxide concentrations, so their effect is often small. Stronger products bought outside that framework, or abrasive powders, can irritate the gums or wear the enamel. An examination beforehand also picks up any decay or gum disease.
Who should not have teeth whitening?
Whitening is not advised under 18, during pregnancy or breastfeeding, or with an allergy to peroxide. It is postponed while decay or gum inflammation remains untreated. Exposed roots and very sensitive teeth also call for caution, which is exactly what the consultation is there to check.
Related treatments
Treatments that are often considered together.
Whiter teeth, done safely
Dr Denis Catarau will see you at the practice in Etterbeek to check whether whitening is right for you, choose the most suitable technique and explain what result you can expect.