Safe, Legal Whitening

The Law in Brief

In the UK, tooth whitening is the practice of dentistry. Only dental professionals registered with the General Dental Council can provide it: dentists, or dental hygienists and therapists working on a dentist's prescription.

Whitening products containing between 0.1% and 6% hydrogen peroxide can only be supplied through dental professionals. The first treatment must be carried out or supervised by a dentist, after an examination to make sure there's nothing that makes whitening a risk, and the products can't be used on anyone under 18, except to treat or prevent disease. Products stronger than 6% are illegal. Products sold directly to the public, such as strips and pens, are limited to 0.1% hydrogen peroxide, which is why they mainly remove surface stain rather than lightening the tooth itself.

Why Salons and Kiosks Are a Risk

Whitening offered in beauty salons, kiosks and pop-ups by people who aren't registered dental professionals is illegal, and the General Dental Council has prosecuted people for it. The products used are often either too weak to work or not legal at all, and some contain chlorine dioxide, which can damage enamel. Some providers get around the law by handing you the tray to put in your own mouth, which doesn't make it legal or safe.

Just as importantly, nobody checks your teeth and gums first. Whitening over decay, a cracked tooth or gum disease can be painful and hides problems that need treating. One-size trays let gel leak onto the gums, which burns them. And if something goes wrong, there's no clinician responsible for putting it right. You can check whether anyone offering whitening is registered on the GDC's online register.

What Professional Whitening Involves

• A dental examination first. We check for decay and gum disease and note any fillings, crowns or veneers, which won't change colour.
• A scan for your trays. A quick iTero Lumina scan of your teeth, with no putty. Your trays are made to fit your teeth exactly, so the gel stays where it should.
• Fitting and instructions. We fit the trays, show you how much gel to use and for how long, and record your starting shade.
• Whitening at home. Usually two to three weeks, wearing your trays for a short time each day with professional Boutique whitening gel.
• A review. We compare your new shade with where you started, and talk about keeping it.

Whitening works because the peroxide in the gel soaks into the enamel and breaks down the stains that darken teeth, lightening them from within. Yellowish teeth usually respond best; grey staining lightens more slowly, and we'll tell you what to expect.

Is It Safe?

Yes, when it's prescribed and supervised by a dentist using regulated products. Temporary sensitivity is common and settles when you stop. Well-fitting trays keep the gel off your gums. Used correctly, professional whitening doesn't damage enamel, and it has been used in dentistry for decades.

There are times we won't whiten: under-18s, except to treat a dental condition; during pregnancy or breastfeeding, as a precaution; and anyone with untreated decay or gum disease, which we treat first. If you already have sensitive teeth, we can adjust how you whiten, and our guide to sensitivity after whitening explains what helps.

Dentist Whitening or a Shop Kit?

Shop kits aren't dangerous in the way salon whitening can be, but at 0.1% they can't do much more than a good toothpaste. If your teeth are genuinely darker than you'd like, they'll disappoint you.

What Whitening Can't Do

Crowns, fillings, veneers and bonding don't change colour. If they're on your front teeth, we'll plan for them to be refreshed or replaced after whitening so everything matches, and if you're planning bonding or veneers, whitening comes first. Some deep or grey staining responds less well, including discolouration from a tooth that has died or from certain antibiotics taken in childhood, and we'll tell you honestly at your consultation what's realistic. Results vary from person to person, so we show you a realistic shade before you start rather than promising a number of shades.

Keeping Teeth White

• Keep your trays and top up with gel from the practice occasionally
• Rinse with water after tea, coffee and red wine, and use a straw for cold dark drinks
• Don't smoke. Smoking stains teeth quickly, even after whitening
• Brush twice a day with fluoride toothpaste
• Keep your hygiene visits: Airflow polishing removes surface staining

Whitening usually lasts a year or more, depending on your habits, and because you keep your trays, a few nights of top-up gel brings the shade back without starting again. Our guide to keeping your teeth white goes into more detail.

What It Costs at St Vincent Smile

Dentist-supervised home whitening with custom trays is £350, or £315 for dental plan members.² That covers the check of your teeth and gums, the scan and custom trays, the professional gel, and your review. Whitening is also included in every Invisalign and composite bonding package, so if you're planning either, you don't need to budget for it separately. Whitening consultations are free, with a £40 deposit refunded within 7 days of attending, and if you'd rather ask a question first, message us on WhatsApp. Our whitening page has the details.

Questions

This guide is general information, not a diagnosis. A dentist needs to examine you to say what is right for your teeth.