Tooth whitening is one method that can lighten the colour of healthy natural teeth. Unlike surface stain removal, it uses products intended to lighten the tooth itself. The change achieved depends on the starting colour, the cause of discolouration and the method used. A fixed number of shades or an identical treatment time cannot be promised for everyone.
What Causes Unwanted Tooth Stains?
Discolouration can have many causes, including naturally dark teeth, age-related changes, drinks such as coffee and tea, and tobacco use. Colour changes may arise from surface stains or within the tooth. Exposure to certain medicines or excessive fluoride during development can be associated with some types of discolouration. Injury to a tooth and changes in the pulp also need assessment. Old fillings and crowns may look different in colour from natural teeth. Whitening does not lighten existing fillings, crowns or dentures in the same way. The cause of a colour difference must therefore be identified before choosing a method, with separate assessment of restorations where necessary.
What Is Tooth Whitening, and How Is It Performed?
The dentist first assesses the teeth, gums and existing restorations. In the clinic, soft tissues are protected as required by the product, and whitening gel is applied to the teeth. Some systems may use light, but this is not necessary for every product. Application time and repetition are determined by the product and the person's condition. Dentist-supervised home methods using individually fitted trays are also available. Product selection and instructions should be based on professional assessment.
How Long Does the Procedure Take?
Some people notice a colour change after the first application. Total treatment time and the number of appointments vary with the cause of discolouration, the method and sensitivity. A fixed requirement of three appointments or at least three days does not apply to everyone.
Who Can Have Tooth Whitening?
Suitability is determined after assessment of tooth and gum health and the cause of discolouration. Whitening is not appropriate for everyone. Decay, gum disease or significant sensitivity may need to be addressed first. The fact that existing fillings and crowns will not change colour is also considered in planning.
Is It Safe?
It is important to use an appropriate product under a dentist's assessment and supervision. Even so, temporary tooth sensitivity or gum irritation can occur. Excessive or incorrect use may increase the risks. It is therefore not possible to guarantee that there will be no side effects.
Can Teeth Return to Their Previous Colour After Whitening?
The effect of whitening may not be permanent in the long term. Diet, tobacco use and oral care can lead to renewed discolouration. Further application may be considered after review, but its timing and extent vary between individuals. Teeth cannot be guaranteed to remain whiter than their original shade indefinitely.