Clear aligner FAQs

Clear aligners are removable plastic trays, each shaped slightly differently, that move teeth in small steps. You wear each tray for the time your plan sets, then move to the next. Even when the trays are posted to you, the General Dental Council (GDC) requires a registered dentist to be responsible for the plan throughout. The stages are in how at-home aligner treatment works.

In the right case they can straighten crowded teeth, close small gaps and improve many bite problems. They cannot move an adult's jaws, replace a missing tooth, move an implant, or treat decay, gum disease or tooth colour. An overbite can come from where the teeth sit, from the jaws, or both, and an in-person examination works out which. See what clear aligners can and cannot treat.

They can, in the right case. The British Orthodontic Society describes aligners as a treatment for mild to moderate problems after a proper assessment. Teeth do not always move as predicted, even when the trays are worn properly, and not reaching the planned result is a recognised risk; the dentist may then order refinement trays or recommend a different approach. See how at-home aligner treatment works.

It depends first on what your teeth and bite need. Fixed braces can handle the widest range of problems. The British Orthodontic Society says aligners are most commonly used to align teeth without extractions, and that severe crowding, extractions, complex movements or a problem with the size or position of the jaws may need extra techniques such as fixed braces. A dentist or orthodontist who has examined you should say which options can do the job. See ways to straighten teeth.

The GDC requires a registered dentist to be responsible for the plan throughout. What differs most between services is whether a dentist examines you in person before aligners are prescribed. For crowding with a bite problem, or a mouth with crowns, implants or gum problems, in-person care is the safer fit. See Invisalign and at-home aligners.

The British Orthodontic Society says aligners are ideally suited to adults whose work or daily life makes a fixed brace difficult. Under-18s with a problem that affects daily life should be assessed for NHS treatment first, which is usually a fixed brace.

Start with how you want to be treated: in a practice, remotely with photo check-ins, or a mix. Then compare what each price includes, who the responsible dentist is, and how you reach them. The find a provider questions shortlist providers that match your preferences; they do not assess whether treatment suits your teeth. You can also compare providers side by side.

Straightening is worth it when the problem bothers you enough to justify the cost, the months of wear and lifelong retainers, and when a dentist who has examined you says the plan fits the problem. See is it worth straightening your teeth?.

The GDC says there is no effective substitute for a physical examination when deciding whether treatment is suitable. Some UK services include an examination; some offer a scan at a partner practice that is described as records only. Ask which you are getting before you pay. See how at-home aligner treatment works.

No. A 3D scan or a home impression kit records the shape and position of the teeth so a plan can be designed and trays made. An examination is a dentist looking at the teeth, gums and bite in person, with X-rays where needed. A good mould is a good record, not a decision that treatment is suitable. The steps for a home kit, and why a mould may be rejected, are in dental impressions at home.

A GDC-registered dentist. The GDC said on 13 May 2021 that you should have a direct conversation with the practitioner, know the full name of the dentist responsible, and be able to contact them directly. If that dentist relies on someone else's examination, the responsibility still rests with them. See how at-home aligner treatment works.

Possibly. Any provider's examination may find something that needs treating before aligners. Smile White, for example, says a scale and polish is not always included and is usually £195, and that fillings or other work needed first are charged separately. See what clear aligners cost in the UK.

A provider that turns you down should not make trays. Whether you get back what you paid for an impression kit or scan depends on its terms: on the sites we checked they cost £54 to £99 when sold separately. Ask whether that fee is refunded if you are not suitable, and whether a repeat kit is free if the first impressions cannot be used. See what clear aligners cost in the UK.

From about £650 for one arch with a remote company to £3,700 or more with a dentist. On 22 October 2026, remote companies listed treatment for both upper and lower teeth at £849 to £1,790. Current prices are on each provider review and in what clear aligners cost in the UK.

It varies, so check before comparing two prices. Dentist-led treatment includes an examination, clinic visits and in-person help if something goes wrong; a remote price mostly covers the aligners and a review of your impressions or scan. Ask about each of these: the impression kit or scan, every aligner, refinements, retainers and replacements, dental visits, and what a lost or broken aligner costs to replace. See what clear aligners cost in the UK.

Usually. Smile Perfect, for example, listed £649 for one arch against £849 for both on 22 October 2026. One arch only works if all the teeth you want to move are on it and the bite still fits afterwards, which the dentist planning your treatment decides. See what clear aligners cost in the UK.

Some do, but a results guarantee is a contract term, not a clinical promise, so ask exactly what it covers, and what is refunded if you are not suitable or stop partway. See what clear aligners cost in the UK.

Clear aligners are not routinely provided on the NHS. NHS orthodontics is mainly for under-18s with a clinical need, and is usually a fixed brace; adults usually pay privately. See what clear aligners cost in the UK.

Many providers offer it. Add up the payments and compare the total with the cash price. On a 0% plan, such as Smile White's, the total matches the cash price. On an interest-bearing plan it does not: Impress's example of £55.22 a month for 48 months at 15.9% APR adds up to £2,650.56 on a £1,990 plan. Check the total, the APR and the term, and what happens to the agreement if treatment stops. See what clear aligners cost in the UK.

Ask before you pay what you get back if you stop, including any fee for the impression kit or scan, aligners you have not worn, and what happens to a credit agreement. Those terms are in the provider's contract, and your statutory consumer rights may also apply. See what clear aligners cost in the UK.

The British Orthodontic Society advises more than 22 hours a day; Invisalign tells its patients 20 to 22. Those hours include the time you sleep, and treatment takes longer when the trays are worn less. At 22 hours, about 2 hours a day remain for eating, drinking and brushing. See mistakes that affect clear aligner treatment.

Yes, for every meal and every drink except water. Brush your teeth with fluoride toothpaste before the trays go back in, because a tray holds anything left on the teeth against them. If you cannot brush, rinse your mouth and the trays with water and brush properly at the next chance.

Not in what you eat, but in when: meals and drinks other than water become breaks from wear, so grouping them helps you reach the daily hours. For a sore tooth, the NHS suggests soft foods such as yoghurt or scrambled eggs, and chewing away from the sore side.

The case and a travel toothbrush with fluoride toothpaste. Never wrap a tray in a napkin; it is easy to throw away with the plates. Cleaning tablets and a removal tool are optional extras; chewies, which help a tray fit fully, are worth using mainly if your dentist or aligner system recommends them. Brushes and cleaners have their own product pages.

Speech can be affected at first, but it usually settles within three to five days. See are clear aligners painful?.

Sore teeth for the first few days of a new tray are expected. The NHS lists ibuprofen or paracetamol for tooth pain, and says children under 16 should not take aspirin. Contact the dentist responsible if pain lasts more than a few days, if gums are very red, swollen or painful, if a tray will not sit fully, or if a tooth feels newly loose. See are clear aligners painful?.

Invisalign's instructions list temporary loosening as an expected effect while teeth move. A tooth that feels very loose, or loose and painful, is different and needs examining before you move on to the next tray. See when clear aligner treatment goes wrong.

Ask the clinician rather than cutting the tray yourself: Invisalign's instructions say not to alter your aligners, and the clinician can advise whether an edge can be adjusted. A tray that fits fully is less likely to dig in. See a dentist if a sore does not heal or the gums are swollen or bleeding. See are clear aligners painful?.

The British Orthodontic Society's method is a soft brush, cold water and liquid soap once a day. Hot water can warp the plastic. Vinegar, bicarbonate, bleach or mouthwash soaks are not part of the published cleaning instructions we checked, so avoid them unless your clinician tells you to. See how to clean clear aligners.

The NHS says adults should use a toothpaste with at least 1,350 parts per million (ppm) fluoride; the packaging shows how much a brand contains. You do not need one marketed for aligners. Spit out the excess after brushing rather than rinsing, so the fluoride stays on your teeth. If your teeth are sensitive, the Oral Health Foundation suggests a toothpaste containing potassium nitrate, potassium citrate or stannous fluoride. Do not scrub the trays with whitening or gritty paste.

No. The NHS says electric and manual brushes are equally good as long as you clean every surface of every tooth with fluoride toothpaste, though some people find an electric brush easier. UK brushes have their own product pages.

Ask the dentist moving your teeth before you whiten. In the UK whitening counts as dentistry, so only a registered dental professional can provide it, and it is not available on the NHS. See whitening your teeth at home.

It depends on how much needs to move. A short course for a small change to the front teeth can take a few months; correcting how the teeth bite together usually takes one to two years, whatever the appliance. See how long clear aligner treatment takes.

It varies by provider, so ask for a timescale. The trays are made by a laboratory after the dentist approves the plan, either all at once or in batches. Smile Perfect, for example, says it ships within 10 to 16 working days of plan approval. See how at-home aligner treatment works.

Wearing the trays less than prescribed: the British Orthodontic Society asks for more than 22 hours a day, and treatment takes longer when they are worn less. A lost tray, a tray that stops fitting, or a tooth that does not move as planned can also add time, and refinements mean more trays. See mistakes that affect clear aligner treatment.

Some companies sell night-time plans and quote a longer treatment for them; Smile Perfect, for example, quotes 6 to 9 months for night-time aligners against 3 to 6 for daytime. The British Orthodontic Society advises more than 22 hours' wear a day. See how long clear aligner treatment takes.

It depends on the service. The British Orthodontic Society describes clinic visits every 6 to 12 weeks, and some practices add remote monitoring between visits. Smile White's hybrid service has at least three clinic visits. Remote services use photos through an online account. Ask who reviews them and how quickly you get a reply. See Invisalign and at-home aligners in the UK.

Not entirely. Photos show whether trays appear to fit fully and whether teeth look on track. They do not show roots, bone or gum health, so keep seeing your own dentist for check-ups. See how at-home aligner treatment works.

On the schedule your dentist sets. If a tray is not fitting fully, do not skip ahead to catch up and do not trim it: contact the dentist before moving on, and follow their advice about which tray to wear meanwhile. See when clear aligner treatment goes wrong.

The dentist responsible for your plan, for anything clinical: a tray that does not fit fully, a sharp edge that cuts, pain that is getting worse rather than better, or a tooth that feels newly loose. Orders, deliveries and payments go to the provider. The GDC says you should be able to contact the responsible dentist directly. See how at-home aligner treatment works.

Extra aligners, made when the teeth have not followed the plan. Teeth do not always move as predicted, even when trays are worn properly, so the dentist may order refinement trays from new records, or recommend a different approach. Retainers come after active movement has finished. See when clear aligner treatment goes wrong.

It depends on your agreement. On 22 October 2026, Straight Teeth Direct included one round of refinements, Smile Perfect one refinement, and Smile White refinements subject to clinical eligibility. Ask how many are included and what happens after that. See what clear aligners cost in the UK.

Ask the dentist, and follow their advice about which tray to wear meanwhile. Do not move on to a tray that does not fit fully, and do not trim one to make it fit. See when clear aligner treatment goes wrong.

They can. Teeth can drift back towards where they started, and the British Orthodontic Society says retainer wear is lifelong. How many hours a day, and which type, are set by the clinician who finished your treatment. See care after clear aligners.

Retainers can be removable, such as a clear vacuum-formed tray or a Hawley retainer with a wire across the front, or fixed, a thin wire glued behind the front teeth. Your orthodontist explains which suits you, and sometimes more than one type is used. See care after clear aligners.

Most packages include a first set; replacements are extra. On 22 October 2026, Straight Teeth Direct's annual retainer plan was £179 a year if your retainers were under 18 months old, otherwise £239 for the first year, and Impress's retainer subscription was from £300 a year. Ask what a replacement costs and how often you are likely to need one. See what clear aligners cost in the UK.

Contact the clinician or provider for a replacement as soon as you can; the risk of teeth moving back is highest in the early months after treatment. Do not force a retainer that does not fit fully. A bonded wire that comes loose can let a tooth drift, so get it repaired. See care after clear aligners.

A tray can look fine in your hand and still sit short of one or more teeth, often with a visible gap at the biting edge. Do not skip ahead and do not trim it. Contact the dentist responsible, with photos of the tray in from the front and each side, and follow their advice about which tray to wear meanwhile. See when clear aligner treatment goes wrong.

Tell the dentist straight away. Invisalign's instructions say your doctor will probably tell you to wear your last or next set while a replacement is made; do not decide that yourself. Keep your previous trays in their case for this reason. See when clear aligner treatment goes wrong.

Contact the dentist responsible and ask whether to go back a tray or forward to the next while it is replaced. Attachments are small tooth-coloured bumps bonded to teeth to help the tray grip, and a tray can stop fitting when one comes off. See when clear aligner treatment goes wrong.

Pain in one tooth for more than a couple of days, sudden severe pain, very red, swollen or bleeding gums, a tooth that feels very loose, or a bite that suddenly feels different need a prompt dental review. Swelling of the face, mouth or neck with difficulty breathing, swallowing or speaking, or swelling around the eye, is an emergency: go to A&E or call 999. See when clear aligner treatment goes wrong.

Do not start new trays without a clinician's advice, and arrange an examination with a dentist or orthodontist. Your own dentist can check for decay, gum problems or a loose tooth even if they did not prescribe the aligners; out of hours, NHS 111 can advise. SmileDirectClub, for example, stopped treating patients when it wound down on 8 December 2023; see what happened to SmileDirectClub in the UK.

Start with the practice or company's own complaints procedure. If a complaint about private treatment is not resolved, the Dental Complaints Service can help if you contact it within 12 months of the treatment, or of becoming aware of the problem. Serious concerns about a dentist can be raised with the GDC. See when clear aligner treatment goes wrong.

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