Crest whitening strips before and after
Whitening strips use a peroxide gel to lighten some external and internal tooth discoloration, but results vary by stain, enamel, and existing dental work.
How much change can whitening strips produce?
Whitening strips use a peroxide gel to lighten some external and internal tooth discoloration, but results vary by stain, enamel, and existing dental work.
How does a strip hold peroxide against the teeth?
A whitening strip holds peroxide against the front tooth surfaces. The oxidizing agent can alter color molecules in natural enamel and dentin, while fillings, crowns, and veneers do not bleach like natural tooth structure.
How can you use whitening strips safely at home?
Read the product directions, keep gel off the gums, stop if marked irritation or sensitivity develops, and have untreated decay or gum inflammation assessed first.
When should tooth colour changes be assessed by a dentist?
See a dentist before whitening when teeth are painful, cracked, heavily worn, mottled, or restored, or when the color change is confined to one tooth.
How will whitening affect your existing dental work?
Is the discoloration on natural tooth structure, and how will the shade of fillings, crowns, or veneers be managed after whitening?
Frequently asked questions
Why might one tooth stay darker?
A single dark tooth can have internal discoloration, decay, trauma, or a restoration that strips cannot whiten.
Can strips irritate gums?
Yes. Peroxide contacting gingiva can irritate the tissue, especially when the strip is mispositioned or used too often.
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.