Tooth Whitening

Tooth whitening is a method which enables us to lighten the colour of your teeth, to give them a more attractive colour and shine. This will improve the appearance of your smile. There are different tooth-whitening techniques, depending on the problem. We will therefore make a complete analysis of your mouth and smile before proceeding.

Thanks to whitening, you can obtain and recover a bright smile.

More information about Dental Aesthetics


Blanqueamiento dental

The preliminary check-up

At the dental clinic, we will start by making a preliminary check-up of your mouth and its health. We must ensure that there is no tooth decay or leaky fillings; should these exist, we must start by repairing them before continuing. Gingivitis too must be treated if it exists

At our surgery, we talk to patients about the appearance they hope to achieve and the need or not for whitening. Sometimes we come across severe cases of quite or very dark coloured teeth due to the fact that, as children, the patient was given an antibiotic. Here we must take account of the fact that, although whitening will improve the brightness of their teeth, should the patient wish them to be even whiter, they would also have to have porcelain veneers fitted.

We use two techniques:

-External whitening of the whole denture.
-Internal whitening of devitalised, blackened teeth.

Whitening of the whole denture

This is done by the patient themselves, at home, overnight, while sleeping. Before starting, their teeth will have been cleaned at the surgery.


Impressions or moulds are taken of the upper and lower teeth. Said impressions or moulds are used to make transparent night guards, as shown in the photograph, which are plastic covers for the top and bottom set of teeth.

The patient will place the whitening gel provided in the night guards as demonstrated at the surgery. The gel is placed in the part of the night guard coming into contact with the exterior surface of the teeth.

At home, the patient will use the night guard with the gel every night while sleeping for two to four weeks, depending on how much their teeth need whitening.

After sleeping with the night guard in for some 6 or 8 hours, the guard is removed, cleaned in water with the effervescent tablet prescribed by us and, when dry, kept in a special box until the following night.

The end result of the treatment is whiter, brighter teeth.


Patients should remember that the whitening gel makes the teeth somewhat more sensitive to hot and cold during the two to four weeks of the treatment, and for a further two weeks after treatment.

While some patients hardly notice it, sensitivity tends to be greater in patients whose gums have retracted or receded, leaving the roots exposed.

This sensitivity is usually tolerable and bearable, especially in the knowledge that it will disappear after treatment. Furthermore, we give the patient toothpaste rich in fluoride to reduce the sensitivity.

Whatever the case, simply avoiding very hot or cold liquids will largely prevent the issue from occurring.


Another aspect to bear in mind is that the patient must not eat food that will stain the teeth during the treatment. While the treatment is underway, the dentine tubules through which the whitening agent enters remain open, meaning that dark food colours can also enter in the same way, causing the whitening results to be a lot less successful than desired.

It is therefore very important not to ingest dark-coloured food such as liquorice, squid in its ink, red wine or dark-coloured beer. Patients can however drink white wine and lager.

In the case of coffee, it is better either not to drink it, or to drink it diluted in plenty of milk. Tobacco too should be reduced as much as possible. This applies both during the treatment, and for the two weeks afterwards. After the treatment is complete, you can return to your usual habits.
During application of the whitening agent, and in the 2 weeks following the treatment, you must therefore take care not to consume the following products:

Medicines containing

● Iron

● Tetracyclines

● Amoxicillin

● Iodides

● Sulphates

● Silver nitrate

● Potassium permanganate

● Cyclosporine

Food and drink

● Food containing colouring agents: paprika, saffron, curry powder, artificial colouring agents.

● Brightly coloured drink: coffee, very dark tea or infusions, red wine, coca-cola, hot and cold drinks.

● Brightly coloured food: chocolate, red fruit, beetroot, rare meat.

● Do not chew: liquorice, chewing gum with chlorophyll, plants, plant roots.


It is also important not to brush your teeth or use a mouthwash containing chlorhexidine.

It is important to clean your teeth well before applying a home whitening product and after eating or drinking.


The best way to keep your teeth white is to ensure that both your teeth and your gums stay in very good health. Inflamed gums cause more plaque to accumulate on the teeth, making them look darker and showing irregular stains.

As usual, you must brush your teeth well and as often as recommended at the point where they meet the gums and for one or two minutes after every meal. Different brands of whitening toothpaste will help to prevent food pigment from sticking to the tooth surface and therefore to maintain their natural colour.

If you smoke and drink coffee, it is advisable that, as well as the whitening toothpaste, you have your teeth cleaned at our clinic every 6 months, given that with a few flakes of rubber we can remove the accumulated plaque causing no damage whatsoever to the enamel. This will ensure that your teeth keep their original or whitened colour.

Tratamiento prevención donostia

Whitening of individual devitalised teeth

In some rare cases, devitalised teeth darken and stand out from those around them. There is a specific treatment for whitening teeth in this situation.

The dentist will open your tooth or molar until coming to the product used to fill the devitalised area. After protecting the interior of the root with a plug, he will insert a whitening gel, which releases oxygen and whitens the tooth.

For the gel to function, it must not come into contact with the air, meaning that the tooth must be properly filled and the channel of access to the whitening gel completely closed.

The gel remains in place for a week, after which we will study the results at the surgery. In the event of wanting it to be whiter, we will replace the gel for a further week. Depending on how dark the tooth is, it will take from two to four weeks to whiten. Finally, once it has acquired the same colour as those around it, the tooth is given another filling in the same colour, recovering the attractive appearance of your smile.

Afterwards, we can also whiten all of your teeth, using the external whitening technique initially explained above.