Orthodontic Aligners
Treatment / Orthodontics / Aligners
aka clear aligners
Treatment / Orthodontics / Aligners
aka clear aligners
This page outlines the main considerations for any patient starting their journey with orthodontic aligners.
This focuses on adult orthodontics with clear aligners, for child orthodontics, please see the relevant page.
Improved Aesthetics. Straighter teeth and a more attractive smile which may lead to improved self-esteem and self-confidence
Enhanced Oral Health. Straighter teeth are easier to clean, reducing the risk of tooth decay and gum disease
Improved Bite. Improving the way the teeth meet, often makes chewing and speaking easier. Better distribution of biting forces reduces wear and tear on your teeth from uneven contacts which in turn lowers the risk of cracked or fractured teeth.
Aligners (invisible braces) are a discreet, modern way to straighten your teeth.
They are thin, transparent, plastic trays that are custom-made to fit snugly over your teeth.
They are programmed to apply small but deliberate pressure on your teeth in order to gently and gradually move them to give you a straighter, more beautiful smile
Orthodontic Assessment. Your dentist will gather detailed information about your treatment goals, expectations, clinical circumstances, dental and general health. This will take the form of a detailed dental assessment, a 3D scan of your teeth, photographs and often x-rays.
Planning. This data will be submitted to an aligner company who will help to design and plan your case.
Smile Simulation Review. Your recommended treatment plan will be presented to you in a manner that is easy to understand, often with an animation showing expected tooth movements and the planned final result. The plan will include the number of aligners needed, estimated treatment time and details of any attachments/IPR needed.
Start of treatment. You will be issued with your series of aligners along with instructions on how to use them. Placement of attachments and IPR as indicated. The aligners are worn in sequence to gradually move your teeth towards the intended position, improving both your bite and appearance.
Reviews. Support from your dentist throughout your treatment journey.
Finish and Refinements. After you have finished wearing your final aligner, if the finished result is not quite as expected, refinements are sometimes needed. This involves making extra aligners and can extend treatment time by a few weeks.
Retainers. Lifelong wearing of your retainers is vital to the long term success of treatment. You can have removable and/or fixed retainers.
Every case is different, and treatment time depends on how many aligners you need and how diligent you are at wearing them.
In general, the more complicated your bite is and the further your teeth have to move, the longer treatment will take.
Most treatments take between 6-18 months
Each aligner needs to be worn for around 10 -14 days, so if you need 15 aligners treatment can take as little as 5 months from the date you start wearing them.
Once active treatment is finished, teeth naturally tend to move back toward their original positions (relapse).
To maintain results, retainers must be worn as instructed, often long-term or indefinitely.
Retention is a lifelong commitment — without consistent retainer wear, the improvements achieved during treatment may be lost.
It is normal to experience some discomfort or pressure, especially when starting a new set of aligners. This is a sign that the aligners are working to move the teeth.
The soreness is usually mild and improves within a few days as the mouth adjusts.
Some patients may also notice temporary tenderness of the teeth or gums, or minor irritation on the cheeks, lips, or tongue.
Over-the-counter pain relief may be used if needed.
Case Suitability. Aligner treatments have a limited scope of applications. For complex cases, a dentist may be required to extract teeth or use alternative appliances where aligners are not suited.
Compliance. Failure in compliance with the instructions provided by your dentist may increase the treatment duration and affect the ability to achieve the desired outcome.
Soreness. It is normal to experience some discomfort or pressure, especially when starting a new set of aligners. This is a sign that the aligners are working to move the teeth. The soreness is usually mild and improves within a few days as the mouth adjusts. Some patients may also notice temporary tenderness of the teeth or gums, or minor irritation on the cheeks, lips, or tongue. Over-the-counter pain relief may be used if needed. Significant or persistent pain is uncommon and should be reported to your clinician.
Undesirable Effects. The aligners may produce undesirable effects in the beginning such as speech impediment, dry mouth or excess saliva production. These effects should subside within a few weeks of consistent use.
Medical Contraindications. Certain medications and medical conditions can affect orthodontic treatment and may make it unsuitable to go ahead with treatment.
Allergies. Aligners are made of plastic and in rare cases, patients may be sensitive or allergic to this material. If you are concerned you may be having an allergic reaction to the aligners, you must remove the aligners immediately, seek medical help and contact your dentist.
Occlusion. The way that your teeth meet (occlusion) may be altered over the course of treatment. Changes to the occlusion can result in disturbance of the bite, tooth wear or temporomandibular disorder that can cause pain and discomfort to the jaw as well as headaches. If altered bite issues persist after treatment has been completed, it is sometimes necessary to see a dentist to have some adjustments made to the teeth to change your bite and improve the stability of your top and bottom teeth.
Tooth Shape/Position. Atypically-shaped, short teeth, partially erupted or missing teeth may affect the ability of the aligners to achieve the desired results.
Existing Restorations. Aligners will not be able to move dental implants and they will sometimes dislodge existing restorations, such as fillings, crowns and veneers in the process of moving teeth. Occasionally, at the end of treatment these restorations will no longer be satisfactory from an aesthetic perspective and may need to be replaced.
Gum Recession. Where teeth have been overlapped for a long time, there may be pre-existing loss of gum attachment near the neck of the teeth, once aligned this can become more apparent resulting in the appearance of a 'black triangle' near to the gum. This is a particular risk for individuals with past history of gum recession or who fail to maintain impeccable oral hygiene throughout treatment.
Compromised Teeth. All teeth, but in particular those that have been previously traumatised or heavily filled, can be compromised by orthodontic tooth movements resulting in the need for further dental treatment and, occasionally, the premature loss of a tooth or teeth.
Root resorption. Root resorption (shortening of root lengths) may result from orthodontic movements which can threaten the life-span of teeth, especially when gum disease is present or develops later in life.
Devitalisation. There is a small risk of devitalisation (death of the nerve in the tooth) and discolouration of teeth as a result of orthodontic tooth movement. This is especially true where teeth need to be moved a long way or if teeth have been previously compromised, resulting in the need for root canal treatment and tooth whitening (in some cases).
Ankylosed Teeth. Aligners will not be able to move teeth that have become ankylosed or locked in their position within the bone. If you feel that any teeth are not moving while the rest are moving around them, please seek advice from your dentist.
During Treatment. There is a higher risk of tooth decay, gum disease or marking/staining of teeth as a result of poor oral hygiene or excessive sugars in the diet during treatment.
Referral. Sometimes teeth do not move as anticipated, so treatment does not progress in line with the plan proposed at the start. If the teeth fail to 'track' and your aligners no longer fit then you might need to be referred to a specialist to finish your treatment with traditional orthodontic approaches (wires, brackets and removable appliances).
Relapse & Retention. Once active treatment is finished, teeth naturally tend to move back toward their original positions (relapse). To maintain results, retainers must be worn as instructed, often long-term or indefinitely. Retention is a lifelong commitment – without consistent retainer wear, the improvements achieved during treatment may be lost.
Aligner Loss/Damage. Aligner breakages can sometimes occur. Replacement aligners can be manufactured, so you must inform your dentist ASAP of any loss or damage.
Fixed Braces. Provide a more traditional method of moving teeth. Utilised in more complex cases where more precise and predictable tooth movements are required.
Composite Bonding or Veneers. Improve the appearance of the smile by changing tooth shape, size, and shade rather than moving the teeth.
~ £3500 upwards
Costs vary depending on the aligner system used, case complexity and length of treatment
Other costs may include: refinements, retainers and additional cosmetic or restorative procedures (whitening, bonding or reshaping) after orthodontic treatment.
As a cosmetic treatment, this treatment is NOT available on the NHS.
Tooth movement is a biological process and even with careful planning, teeth may not move exactly as expected.
Compliance with wearing aligners, case complexity, and individual variation can all affect the outcome.
The more complex the case, the less likely it is that treatment will match the anticipated final desired result with aligners alone, and the greater the likelihood that refinements or alternative treatments will be required.
An orthodontic case is considered complex when it involves:
Severity of malocclusion – large overbites, underbites, or open bites.
Severe crowding or spacing – particularly when extractions or expansion are required.
Skeletal discrepancies – when jaw size or position contributes to the problem (may require surgery or fixed appliances).
Rotated or impacted teeth – especially premolars or canines.
Missing teeth or bite collapse – requiring space closure or redistribution.
Previous dental work – implants, bridges, or crowns that restrict movement.
Age and biology – adult cases may be slower or more resistant than adolescent cases.
Patient compliance – inconsistent wear of aligners, elastics, or retainers.
While aligners are excellent for mild to moderate alignment, some movements are less predictable and often require attachments, elastics, or refinements:
Severe rotations – particularly round teeth like canines and premolars.
Extrusion (pulling teeth down/out) – especially single teeth.
Intrusion (pushing teeth up/in) – though multiple-tooth intrusion can be effective.
Large bodily movements – moving a tooth (especially molars) bodily rather than tipping.
Root torque – changing the angulation of tooth roots within bone.
Significant midline corrections – especially without extractions or skeletal anchorage.
Molar uprighting and distalization – moving molars backward or upright is more challenging with aligners compared to braces.
To maximise treatment success, aligners should be worn for as long as possible, at least 22 hours per day.
Only remove your aligners when eating, drinking and cleaning your teeth.
As a general guide, each set of aligners should be worn for 10-14 days.
However wear frequency is case dependant.
Please follow the instructions from your dentist.
Orthodontic treatment changes the position of the teeth but does not alter their natural shape, size, or shade.
At the end of treatment, additional cosmetic or restorative procedures (such as tooth whitening, bonding, contouring, or veneers) may be necessary to enhance the final appearance.
Attachments are small, tooth-coloured bumps (or buttons) made of a composite material that is bonded to your teeth temporarily during treatment.
Attachments act like “handles” to help the aligners grip providing extra stability and small forces to help move your teeth into their desired positions with more efficiency, precision and accuracy.
Attachments are usually discreet but may be slightly visible, especially on front teeth. They can also feel rough or catch food initially.
At the end of treatment, attachments are polished off, and the tooth surface is smoothed back to its original condition. This process is quick and does not damage the tooth structure.
Without attachments, treatment time may be extended or the desired results may not be possible, as there would be nothing guiding your teeth into the ideal position.
Interproximal Reduction (IPR) is the selective removal of some of the outer tooth surface between the teeth which can create the space needed to allow you teeth to move into the ideal position.
If your teeth are moderately crowded, IPR often works well. If your teeth are more severely crowded, then tooth extraction(s) may be needed.
IPR only takes a few minutes and is normally done in a single visit or spread over several visits, depending on how much space is required.
IPR does not hurt, as only a very thin layer of enamel is removed, and no anaesthetic is required. You may feel a strange pushing/pulling pressure during the procedure.
This procedure is also sometimes called enamel reduction, slenderising or tooth stripping.
Without IPR, treatment time may be extended or the desired results may not be possible, as there is not enough space to move your teeth into the ideal position.
Elastics are small, medical-grade latex or non-latex bands that attach to the aligners using special cut-outs, buttons, or hooks.
Elastics are used help move teeth in ways that require extra anchorage or directional force.
They are replaced daily, since they lose elasticity over time
Compliance is critical – if elastics aren’t worn as instructed, treatment may not succeed or may take much longer.
Bite blocks are a feature in aligner treatment designed to keep upper and lower teeth from touching (disclusion) during orthodontic treatment. This allows certain tooth movements to occur.
You can get anterior bite blocks (also called bite ramps or turbos) or posterior bite blocks.
Bite blocks may feel a bit odd at first. Until you get used to it, the bite block may interfere with the placement of your tongue, both at rest and while talking, but this will improve over time.
Refinements are additional sets of aligners made after the initial series is complete. They are used to make further corrections if teeth have not moved as predicted or if the final alignment still requires improvement.
Refinements are common and are required in a significant proportion of cases, particularly in more complex treatments. They should be considered a normal part of the aligner process rather than an exception.
To get best results from your aligner treatment, your teeth must fit perfectly in each aligner. By biting down on Chewies each time you put your aligners in, you'll help ensure a snug fit for your teeth; especially useful when you first have new aligner trays.
Biting down on these firm foam cylinders helps to seat your aligners, improving the accuracy of fit over your teeth and speeding up your treatment. With proper care, two aligner Chewies can last for a long time.
They can be cleaned with soap and water, or diluted mouthwash.
For aligners to work they need to have a snug fit to your teeth, which can sometimes present a problem when they need to be removed for eating and cleaning.
Some patients struggle to remove their appliance, which can be frustrating and lead to sore and broken fingernails.
An aligner removal tool makes it easy to position and remove aligners safely and hygienically.
TOP TIP: Always remove your aligners by gently lifting them from the inside (towards your tongue or palate) rather than pulling from the outside with your fingernails. This helps prevent cracking, warping, or damaging the edges of your aligners.
As the name suggests, they 'retain' your teeth in their new position.
There are 2 main types of retainers:
Removable. Clear retainer with a very similar in look and feel to your aligners. Usually worn on a part-time basis. You must never eat or drink with the retainer in place. Initially it grips your teeth firmly, but most patients adapt very well to this type of retainer.
Fixed. A thin metal wire is bonded to the back of your teeth, so it is not visible. The advantage is that you don’t need to remember to wear this retainer (as it stuck in full-time). However, you must spend extra time cleaning around it and if it ever gets loose, you should seek advice ASAP.
There are two reasons for wearing retainers:
Teeth tend to want to move back towards their original positions. This is called relapse.
As we get older our teeth may start to move unpredictably, often showing some crossing over and increased in crowding.
By wearing retainers long-term we can reduce these age changes in the position of the teeth. The longer you wear retainers, the longer you can keep your teeth straight.
Your dentist will able to advise you specific to your case, but general guidance is:
Full-time (up to 22 hours a day) for the first 4 months
Daily (overnight) for the following 12 months
Every 2-3 days (overnight) for life. [In some cases, it may be possible to reduce your retainer wear to once a week but this is case dependent]
If your retainers ever begin to feel 'tight', it may be a sign your teeth are beginning to move due to your retainer is not fitting as well, or you are not wearing it often enough. If this happens, consult your dentist ASAP.
Simply put, wear your retainer for as long as you want to have straight teeth
Changes in the position of your teeth can continue throughout life as part of the normal ageing process. The only way to counteract this is to wear your retainers.
See your dentist ASAP to have a new one fabricated
Go back to wearing your previous aligner, to prevent your teeth moving in the interim, whilst you are waiting for your new aligner to be fabricated
A toothbrush and cold water works most of the time.
Do NOT use hot water or toothpaste, as these can damage the retainer.
If you have stubborn stains a dedicated retainer cleaner may help
Your dentist will be in charge of your treatment, using an external company to fabricate your aligners.
There are many aligner systems out there, including: Invisalign, 32co, Angel, Smilelign, Sparx and ClearCorrect to name a few.
Fixed braces are made up of small brackets attached to each of your teeth and joined by a wire.
Fixed braces are a more traditional method of moving teeth and are still widely utilised where more complex tooth movements are required.
Discrete and virtually invisible - made of a clear material with no metal brackets on your teeth
Comfortable - kinder to the soft tissues inside your mouth
Easy to clean - as you can remove your aligners, it makes cleaning your teeth much easier
Eat anything you want - remove your aligners before eating. You don't have to avoid hard/sticky foods.
You may have heard aligners that can be sent direct to your home and you don't need to see a dentist. This has also been called 'direct to consumer' or DIY orthodontics.
The dental profession has concerns about this treatment, and the General Dental Council has released guidance for patients:
Treatment outcomes also tend to be limited because attachments and IPR is not used.
If you are considering this type of treatment, please ensure you do thorough research including:
Who is there to fix any problems you may encounter?
What do you do if things go wrong?
What sort of guarantee do you have?
What negative experiences have other consumers had?
The most well known company that offered this type of treatment was Smile Direct Club, which filed for bankruptcy in 2023.