Bright white smile teeth whitening
Teeth whitening lightens natural tooth colour by using peroxide, but fillings, crowns, and veneers do not whiten with the teeth.
The short answer
Teeth whitening uses a peroxide gel to lighten stains in natural enamel and dentine, while tooth-coloured fillings, crowns, and veneers keep their existing colour. The result depends on the original shade, stain type, tooth condition, and method used.
What causes surface and internal tooth discolouration?
External stains collect on enamel from foods, drinks, tobacco, or plaque, while internal colour changes can arise within dentine or during tooth development. Whitening changes tooth colour chemically and does not repair decay or replace a restoration.
How can you prepare your teeth for whitening?
Have the teeth and gums examined before whitening, then use a dentist-provided or appropriately directed peroxide method. Follow the application time exactly, avoid whitening over untreated decay, and maintain the result with plaque control and stain-conscious habits.
When should dental problems be treated before whitening?
Seek an examination for pain, cavities, cracked teeth, gum disease, or one dark tooth before using whitening gel. Stop and contact a dentist if marked sensitivity, gum irritation, or an uneven colour change develops.
What should you ask about shade matching after whitening?
Ask whether the discolouration is external or internal, whether existing restorations will match afterward, and which peroxide concentration and tray design fit your teeth. Ask how sensitivity will be managed if it occurs.
Frequently asked questions
Why did whitening make my teeth look uneven?
Natural teeth can lighten while restorations retain their former shade, and different stain types can respond differently.
Can whitening remove every stain?
No. Some internal discolouration needs restorative or other treatment rather than peroxide alone.
Who wrote this page
This library is published by Dental Nation, a licensed dental group practising in the United Arab Emirates. Pages are written and overseen by the same clinical team that treats patients in our clinics, and are held to a fixed editorial standard for safety and accuracy.
This page is patient education, not medical advice, and cannot replace an examination. Anything urgent — facial swelling, trauma, uncontrolled bleeding or severe pain — needs a dentist or emergency care now.