Tooth discolouration and tooth whitening

Tooth discolouration and tooth whitening

We all have an individual, genetically defined tooth colour. Some people naturally have more yellowish, greyer or whiter teeth than others. The thickness and composition of the enamel and the dentine are mainly responsible for the individual tooth colour. External influences can cause tooth discolouration over time.

Tooth discolouration is often primarily a cosmetic and not a medical issue. Yet both cases should be taken seriously as they can have a negative impact on quality of life. Various tooth whitening methods are available to make the teeth whiter again: These range from bleaching to whitening toothpaste.

You should discuss the right method for you with your dentist. It is important to know which type of tooth discolouration you have.

Internal and external tooth discolouration

In principle, a distinction is to be made between internal (intrinsic) and external (extrinsic) tooth discolouration:

  • Internal tooth discolouration occurs in connection with the dentine and enamel. The dentine is darker and more yellow than the overlying enamel. Wearing down of the enamel (e.g. by pressing too hard when brushing your teeth) causes the dentine to shimmer through more and the teeth look yellower. The tooth colour is also influenced by deposits in the tooth (e.g., from some medicines) and dental disease, such as caries.
  • External tooth discolouration only occurs on the surface of the tooth. When consuming various foodstuffs, substances build up on the enamel. They attack the teeth and lead to dark spots. Dental plaque and tartar, which accumulate and harden on the outside of the tooth as a result of poor dental care, can also lead to discolouration.

Causes of external tooth discolouration

When consuming various foodstuffs, substances build up more easily on the enamel, these attack the teeth and lead to dark spots:

  • Coffee and tea
  • Red wine
  • Sugary fruit juices
  • Fruit, particularly blueberries and (sour) cherries
  • Soft drinks such as cola and iced tea
  • Spices such as curry and safran
  • Balsamico vinegar

Tobacco and smoking also impact on the colour of teeth and dark build-ups on the surface of the teeth can form more quickly. Even some components of dental care products can cause external discolouration of the teeth. In particular, these include products containing tin and those containing chlorhexidine. 

Foodstuffs lead to tooth discolouration

Thorough and regular dental care normally helps to remedy external discolouration and to ensure that stubborn tartar and plaque cannot build up in the first place.

Reasons for internal tooth discolouration

Incorrect dental care, dental surgery and the use of medication also have a negative effect on the appearance of the teeth:

  • White or yellow spots on the teeth (fluorosis) can result from too much fluoride ingestion during childhood.
  • Medication can cause discolouration if it builds up in the teeth, for example due to overdoses of antibiotics (especially tetracyclines) and increased concentrations of iron as a food supplement.
  • Dental interventions, e.g., a filling for caries or broken teeth (e.g., with amalgam) or root canal treatments, can lead to the teeth becoming greyer.
  • A dead tooth turns yellow or grey in colour. In this case you must consult your dentist and have the dark tooth examined. If the nerve of a tooth has died, this usually leads to inflammation, which can be very painful. Not only are the gums and the jawbone affected, but general health also suffers from the bacteria involved.

Treatment of external tooth discolouration – professional tooth cleaning, home bleaching & whitening toothpastes

Superficial discolouration is comparatively easy to remove:

  • Professional teeth cleaning: Most yellow and brown coatings can be removed by professional teeth cleaning in the practice using special polishing pastes, ultrasound and powder and water mixtures.
  • Home bleaching: The dentist has customised bleaching trays made for your teeth. These can be coated with bleaching gel at home and applied yourself.
  • Special toothpastes: "Whitening" toothpastes contain special additives or particles that aid the thorough removal of superficial discolouration and polish the tooth surface. This effect is achieved by abrasive ingredients (grinding particles which can remove tooth material). Important: There is a risk that the hard tooth substance is damaged.
Professional teeth cleaning removes extrinsic tooth discolouration

Caution: With toothpastes with abrasive properties there is risk that the hard tooth substance is reduced. You should not use such products if the enamel is already damaged.

Methods for treating internal tooth discolouration – tooth bleaching with peroxides

If the discolouration is inside the tooth, normally the only effective method is professional bleaching in a practice. However, realistic expectations are important. Since everyone's teeth react differently to peroxide, you can't expect a bright white Hollywood smile.

  • Professional bleaching: With whitening in the dental practice, the dentist applies a highly concentrated bleaching agent (peroxide) directly to the teeth and accelerates the whitening process by using a laser or UV light. This bleaching treatment can be repeated several times until the desired degree of lightening has been achieved. The teeth and gums may feel more sensitive than normal after treatment. The durability of the result depends on your lifestyle.

The best and most suitable procedure for tooth whitening depends on the discolouration of your teeth and should be discussed in advance with your dentist.

Important: One of the most common side effects of professional bleaching is increased sensitivity to pain in the teeth during or after treatment.


Preventing tooth discolouration – what you can do

Daily oral hygiene is essential for anyone who wants whiter teeth. Regular tooth brushing (twice a day), the use of floss to clean between the teeth and mouthwash to rinse off plaque are effective methods of caring for your teeth and preventing discolouration.

Those who can should also avoid eating discolouring foodstuffs. The discolouring effect of coffee and tea can be reduced, for example, by adding milk. Dental chewing gums increase the salivary flow and thus help to reduce any build-up. Rinsing with water after each meal has proven to be a good way to neutralise the oral cavity and minimise the build-up of residue on the teeth.


Dental care for white teeth

Product recommendation for daily tooth cleaning

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