Tooth whitening

What is tooth whitening?

Tooth whitening is an increasingly popular procedure.


There are two types of tooth whitening processes :


  • The first is a chemical process that alters the internal colour of the teeth;
  • The second is a mechanical process that is designed to remove surface stains from the teeth.


Some of the most common whitening techniques include :


  • at-home whitening trays custom made by a dentist combined with follow-up appointments at the dentist’s office.
  • chairside whitening performed by a dentist.
  • chairside whitening performed by a dentist combined with custom-made trays used at home.
  • the use of certain over-the-counter products.
Chemical whitening

In the chemical tooth whitening process, a peroxide-based gel is applied on teeth to remove discoloration. When the peroxide comes into contact with the teeth, it eliminates any pigments that have accumulated in the enamel and dentine, which alters their colour.


The effects of this procedure depend on the concentration of the product used, whether it is hydrogen peroxide or carbamide peroxide, and on the duration of the contact between the product and the teeth.


Risks associated with chemical tooth whitening


Certain side effects can be associated with a chemical teeth whitening process, regardless of the technique used.


  • Teeth can become hypersensitive because of the whitening product.
  • The throat or gums can become irritated when a tray is improperly adjusted or the whitening product is swallowed.
  • Discomfort may be felt in a joint when trays are worn.


If you experience one or more of these effects, please consult your dentist immediately.



Contraindications for chemical whitening


  • Women who are pregnant or breastfeeding.
  • Individuals who have a very deep cavity.
  • Individuals who have a serious oral disease, such as cancer.
Mechanical whitening

In the mechanical tooth whitening process, stains are removed from the surface, or tooth enamel. It should be noted that this type of procedure cannot alter the internal colour of teeth.

Here are a few examples :


  • Brushing teeth twice a day with a soft bristle toothbrush and fluoride toothpaste.
  • Using toothpaste that contains abrasive particles (baking soda) or chemical products (hydrogen peroxide).
  • Chewing gum after a meal to stimulate saliva and help dislodge certain foods between the teeth or to reduce dental plaque near to the gums.
  • Using mouthwash to reduce the quantity of bacteria and prevent the accumulation of dental plaque.



So-called natural teeth whitening toothpastes


These types of toothpastes generally do not contain fluoride, a proven ingredient in the prevention of cavities. Since the degree of abrasivity of the particles found in these toothpastes is unknown, these types of products could cause premature wear and tear and affect the enamel, which can lead to hypersensitive teeth. We recommend that anyone who wants to use these products speak first to their dentist about them.



Activated charcoal products


Activated charcoal products (toothpastes or powders mixed with water) can remove surface stains on teeth during brushing due to their abrasivity. However, they can leave an undesirable tint on teeth and gums. It should be noted that some types of activated charcoal toothpastes do not contain fluoride, a proven ingredient in the prevention of cavities. Due to its adsorptive capacity, the charcoal in these products may neutralize the fluoride.

Informative video – Tooth whitening

In addition to performing a complete examination of your mouth, your dentist can :


  • determine why your teeth are not as white as before and assess the chances of a successful treatment;
  • recommend the best whitening method for you;
  • regularly monitor the results of the treatment.


A prior dental examination by a dentist is particularly important for people how have had many dental restorations. In fact, some restorations, especially those located in the front of the mouth, may need to be replaced after whitening so that they match the colour of the teeth.


Toothpaste, mouthwash, chewing gum and other whitening products do not change the colour of your teeth. They simply remove surface stains.

Some people get better results from whitening treatments than others. Individuals with yellowish teeth usually have better results than individuals with greyish teeth.

What you need to know

Regardless of the chosen technique, it is safe to whiten teeth with products designed for that purpose, provided the process is carried out on a dentist’s orders and the dentist has made certain checks prior to the treatment.


Consult your dentist before choosing a teeth whitening technique.

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