How hydrogen peroxide whitens teeth
Hydrogen peroxide breaks down into water and oxygen. That oxygen passes through the enamel and breaks the colour molecules held inside the tooth into smaller, paler ones. This is a real change in shade, unlike the surface polishing described in our guide on baking soda teeth whitening.
Many whitening gels use carbamide peroxide, which breaks down into hydrogen peroxide in the mouth. Either way, results depend on how strong the product is, how long it stays on the tooth and how stained the tooth is. The steps in a clinic are described in our guide on the teeth whitening procedure.
Why a rinse or pharmacy solution is not the same
In a clinic, the dentist checks the teeth first, protects the gums with a barrier, controls the strength and the time, and stops if you are uncomfortable. At home with a bottle of antiseptic peroxide solution, none of that exists.
Solutions sold in pharmacies for cleaning wounds are not made for whitening. They are not designed to sit against the gums, their strength is not suited to the mouth, and swishing a rinse over the teeth for a short time does little for colour while still irritating the soft tissue. A runny liquid also flows onto the gums, where it can cause white patches and burning, as in our guide on white gums after whitening.
Never swallow it. Do not use peroxide on children or in pregnancy without a dentist's advice.
Side effects and who should not whiten
The common side effects are tooth sensitivity, often a sharp zing to cold that fades in a few days, and gum irritation. Both usually settle, but sensitivity can be strong in people with worn enamel or exposed roots.
Peroxide does not whiten crowns, veneers or fillings, so they will not match the new colour. Cavities, cracks and gum disease should be treated first, because peroxide can reach sensitive tissue through them.
If you want a change in shade, see a dentist first, as the smile design page explains. Our guide on whether teeth whitening is safe covers risks in more detail, and the teeth whitening cost page covers price.
Common questions
Can I rinse with hydrogen peroxide to whiten my teeth?
It is not recommended. A rinse touches the teeth briefly and will do little for colour, while the liquid can irritate the gums and lining of the mouth. Safe, effective whitening is done with products made for teeth, with the gums protected.
Is hydrogen peroxide whitening bad for enamel?
Used as directed, whitening products do not appear to damage enamel in a way that matters for most people. Misuse, overuse or poor products can irritate the tooth and gums, so follow your dentist's instructions.
Why do my gums turn white during whitening?
The peroxide has irritated the gum surface, which turns white temporarily. It usually fades within hours. It is a sign the gel touched the gum and the fit or technique needs fixing.
How long do results from peroxide whitening last?
It varies with how much you drink tea, coffee or smoke or chew tobacco, and how well you clean. Colour gradually drifts back, and some people have occasional top-ups. A dentist can advise what to expect.
About this page
This page is general information, not a diagnosis or a quotation. Prices are prevailing Lucknow market ranges. Your own treatment and cost are determined after an examination. For questions about your own case, call +91 83036 12717.