Crest level 12 whitening strips
Whitening strips are flexible plastic strips coated with peroxide gel; use them only as directed, and stop if marked sensitivity or gum irritation dev
The short answer
Whitening strips are flexible plastic strips coated with peroxide gel; use them only as directed, and stop if marked sensitivity or gum irritation develops.
What are Crest Level 12 whitening strips?
Whitening strips place a peroxide-containing gel against the front surfaces of teeth. The gel can lighten some surface and internal stains, but it does not change the colour of fillings, crowns, veneers, or other restorations.
Why can Level 12 strips irritate teeth or gums?
The product name refers to an over-the-counter tooth-whitening strip, while “level 12” describes a product variant rather than a dental diagnosis. Whitening can irritate exposed dentine or the gingival margin, especially when the strip overlaps the gums or is used too often.
Whitening strips contact enamel with peroxide gel.
How should I use Level 12 strips correctly?
Check that the strip fits the visible tooth surfaces, keep it off the gums, follow the package wear time, and do not combine it with another peroxide product. Use a soft brush and ordinary fluoride toothpaste while monitoring sensitivity.
Keep a record of changes and bring the product, appliance, or medication list to the appointment so the clinician can assess the relevant details.
When should I seek care after using whitening strips?
Arrange a dental examination before whitening if a tooth is painful, cracked, unusually dark, or has a cavity. Seek care promptly for facial swelling, severe pain, or a gum reaction that continues after the strip is removed.
Do not delay assessment when symptoms are escalating, recurring, or affecting eating, sleep, mouth opening, breathing, or swallowing.
What should I ask before choosing a whitening method?
Ask whether the darkening is a stain or a sign of decay, whether any fillings will remain a different shade, and which whitening method suits your enamel and gum condition.
Ask what the examination found, which treatment is intended to address the cause, and how you will know whether the problem is improving.
Frequently asked questions
Can strips whiten fillings?
No. Peroxide can lighten natural tooth structure but does not recolour fillings or crowns.
What if the symptom keeps returning?
Arrange an examination because recurrent symptoms can need treatment of an underlying tooth, gum, appliance, or jaw problem.
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.