Take-home teeth whitening means placing a low-concentration gel supplied by your dentist into a custom clear tray made from impressions of your mouth and wearing it for set periods. Depending on the gel, the tray is worn for 30 minutes to a few hours a day, or overnight. Treatment usually takes 1–3 weeks in total. The first application and follow-up are carried out under your dentist's supervision.
What is take-home teeth whitening?
Take-home teeth whitening is a method in which whitening is carried out at home to a plan set by your dentist. The dentist first examines you, takes impressions and has a custom tray made. They then show you how to use the gel and carry out the first application in the clinic.
This method is different from ready-made products bought in shops or online. The tray fits your teeth exactly, the gel does not spill onto the gums and the process is monitored by the dentist. For information on ready-made products, see our teeth whitening at home page.
How is a custom whitening tray made?
A whitening tray is a thin, clear, flexible tray made from impressions or a digital scan of your mouth. The tray wraps closely around your teeth, so the gel stays on the tooth surface and is not diluted by saliva.
- Examination: Decay, gum disease and sensitivity are checked; any necessary treatment is done first.
- Cleaning: Any tartar is removed; this matters so that the gel contacts the teeth evenly.
- Shade record: Your starting shade is measured with a shade guide and photographed.
- Impressions: Impressions of the upper and lower jaws are taken, or a digital scan is made.
- Fitting: The tray is ready within a few days; it is tried in and you are shown how to use it.
Some trays have small reservoirs on the front of each tooth to hold the gel. If the tray digs into or rubs your gums, do not trim it yourself; your dentist will adjust it.
How is the gel used?
The gel is placed as a small drop in the part of the tray that corresponds to each tooth. Using more gel does not speed up results; on the contrary, excess gel can irritate the gums.
- Brush your teeth and floss.
- Place a rice-grain-sized amount of gel in each tooth compartment on the front of the tray.
- Seat the tray and wipe away any excess gel with a clean finger or cotton pad.
- When the time is up, remove the tray, rinse your mouth and rinse the tray in cold water.
- Keep the tray in its case away from sunlight and heat; store the gel somewhere cool.
Take-home gels usually contain carbamide peroxide or low-strength hydrogen peroxide. Carbamide peroxide releases hydrogen peroxide equal to roughly a third of its weight. Under the regulations, products containing more than 0.1% and up to 6% hydrogen peroxide are sold only to dentists, and the first application is carried out by the dentist.
How many hours is the tray worn?
Depending on the type and concentration of the gel, the tray is worn for between 30 minutes and a few hours a day. Some protocols use a low-concentration gel overnight while you sleep. Your dentist decides the right time, and you should not extend it on your own.
| How it is used | Daily wear | Note |
|---|---|---|
| Daytime, short | About 30–60 minutes | Usually with gels containing hydrogen peroxide |
| Daytime, longer | About 2–4 hours | With low-concentration carbamide peroxide |
| Overnight | While you sleep | Only if your dentist considers it suitable |
Extending the time does not noticeably improve the result, but it does raise the risk of sensitivity and gum irritation. If you miss a day, do not double up the next day; simply carry on with the schedule where you left off.
How long does treatment take overall?
Take-home whitening usually takes 1–3 weeks. On yellowish teeth, results often become noticeable in the first weeks. For greyish or stubborn medication-related discolouration, the dentist may extend the time or recommend combined whitening.
The change in colour is gradual. This means slower but more controlled progress than in-office whitening. Many people see being able to stop at exactly the shade they want as an advantage of this method. Check-up appointments are planned roughly a week apart during treatment.
Common mistakes and risks
Most problems with take-home whitening arise when instructions are not followed. Common mistakes include:
- Putting too much gel in the tray and not wiping away the excess
- Wearing the tray for longer than your dentist advised
- Carrying on without a break even though sensitivity is increasing
- Using gels bought online whose contents are unclear
- Eating or drinking coloured drinks with the tray in
- Prolonging the process without attending a dental check-up
The most common side effects are temporary tooth sensitivity and gum irritation. Sensitivity usually passes within 24–72 hours. If symptoms get worse, take a break for a day or two and let your dentist know. For ways to cope with sensitivity, see our sensitivity after whitening page.
What is the difference between take-home and in-office whitening?
The key difference is speed and control: in-office whitening gives results in a single appointment, while take-home whitening progresses gradually over a few weeks. Take-home gel is lower in concentration but stays in contact with the teeth for longer.
- In-office: At the clinic, a session of about 45–90 minutes; the dentist manages every stage.
- Take-home: At home, usually 1–3 weeks; the dentist plans and monitors it.
- Sensitivity: Can occur with both methods; with take-home whitening it is easier to manage by adjusting wear time.
For information on the procedure carried out in the clinic, see our light-activated teeth whitening page.
Who should not have take-home whitening?
People under 18, those who are pregnant or breastfeeding, and those with untreated decay or gum disease should not have take-home whitening. In these cases the necessary treatment is done first or whitening is postponed.
Marked gum recession, severe sensitivity, jaw joint problems or a gag reflex that makes wearing a tray difficult are also taken into account. Fillings or crowns on the front teeth do not change colour. The full list is on our who should not have whitening page.
Follow-up and maintenance
Check-up appointments during and after treatment are important for a safe, natural-looking result. Your dentist measures the shade, checks your gums and shortens or extends treatment if needed.
- Do not throw your tray away when treatment ends; it can be used for short top-ups later.
- Agree the timing and length of top-ups with your dentist.
- Have a check-up every six months and tartar removal when needed.
- Cutting down on tea, coffee and smoking helps the shade last longer.
Depending on lifestyle, the result can last about 1–3 years. To compare with other options, see our teeth whitening methods page.
Frequently asked questions
How many hours is a whitening tray worn?
Depending on the gel, it is worn for 30 minutes to a few hours a day, or overnight if your dentist considers it suitable. Your dentist decides the time.
How many days does take-home whitening take to work?
The first change is often noticeable within a few days. Treatment usually takes 1–3 weeks in total and varies from person to person.
Can I sleep with the tray in?
Some low-concentration gels are suitable for overnight use. This is your dentist's decision; do not use a daytime gel overnight.
Is take-home whitening as effective as in-office whitening?
Used regularly for the right length of time, it can give similar results. In-office whitening is faster, while take-home whitening progresses more gradually.
Can I share my tray with someone else?
No. The tray is made only for your teeth and is personal for hygiene reasons.
Can I drink coffee during whitening?
You are advised to cut down on dark drinks throughout treatment and not to drink them at all with the tray in. If you do, rinse your mouth with water afterwards.
Related pages
Combined Teeth WhiteningA planned approach that combines the speed of a light-activated session in the clinic with the gradual effect of a custom tray used at home.
Light-Activated Teeth Whitening (In-Office)A single-appointment treatment carried out in the clinic under a dentist's supervision, using blue-violet light, whitening gel and a gum barrier.
Teeth Whitening at Home: Do Over-the-Counter Products Work?Find out what strips, pens, toothpastes and LED kits really do, their risks, and how they differ from dentist-supervised take-home whitening.
Teeth Whitening Methods: Which One Suits You?Compare in-office, at-home, combined and internal whitening, pharmacy products and scale and polish side by side using the same criteria.
Sensitivity After Teeth WhiteningWhy teeth feel sensitive after whitening, how long it lasts and what you can do to ease it.Suitability is decided at an examination. Fill in the form or call us to book an appointment.
Last updated: 2026-11-03 · This page is for general information only and does not replace an examination or diagnosis.