How Does Teeth Whitening Work?
Professional whitening gels contain an active whitening agent that breaks down stain molecules within the enamel, lightening the tooth from the inside rather than just polishing the surface. Before any whitening begins, the dentist checks your teeth and gums, since cavities or gum problems should be treated first. A scale and polish beforehand removes plaque and surface staining, so the gel can work more evenly.
What Is The Difference Between In-Chair And At-Home Whitening?
In-chair whitening is done at the practice during a single, longer appointment. Your gums are protected with a barrier, and a professional-strength gel is applied to the teeth in timed cycles. It suits people who would like a noticeable change in a shorter time.
At-home whitening uses custom trays made from impressions of your teeth. You wear the trays with a lower-strength gel for a set time each day, usually over one to two weeks. The change is more gradual, and many people keep their trays for occasional top-ups. Some patients choose to combine both approaches.
Is Whitening Suitable For Everyone?
Whitening only works on natural tooth enamel. It will not change the colour of existing crowns or fillings, so these may need replacing afterwards to match your new shade. Whitening is generally not recommended during pregnancy or while breastfeeding. Very deep or grey staining can be harder to lift, and for teeth like these, porcelain veneers may be discussed as an alternative.
What Should You Know Before You Start?
- temporary sensitivity is common and usually settles within a day or two
- results vary from person to person, depending on the type and depth of staining
- cutting back on dark drinks helps the new shade last longer
- smoking causes staining to return more quickly
If you are planning to straighten your teeth with clear aligners, it usually makes sense to whiten once that treatment is complete, so the shade can be matched to your final smile.
Find Out Whether Whitening Suits Your Teeth