Clear Aligners: How Removable Transparent Appliances Work, Wearing Time and Cases Where They Are Hard to Use
Clear orthodontics is a method of moving teeth by changing, stage by stage, transparent plastic trays made with 3D digital imaging technology. The Korean Association of Orthodontists (KAO, 대한치과교정학회) explains that because the tray can be taken out and cleaned, hygiene is easy to manage and it is not very noticeable, but that it must be worn most of the day except for meals and brushing. It cannot treat every malocclusion, so start only after an accurate diagnosis at a dental clinic.
Key facts
| Appliance form | Removable transparent plastic tray (source: Korean Association of Orthodontists) |
|---|---|
| Recommended wear | Almost all day, removed only for eating and brushing (source: Korean Association of Orthodontists) |
| Scope of use | It cannot treat every malocclusion, so an accurate diagnosis is essential (source: Korean Association of Orthodontists) |
| Aligners sold online | Various side effects have been reported; do not use (source: Korean Association of Orthodontists) |
| Health insurance | Dental orthodontics is not covered (exceptions notified for cleft lip and palate and similar) (source: National Health Insurance Service (NHIS, 국민건강보험공단)) |
How do clear aligners move teeth?
The teeth are scanned or an impression is taken to make a 3D model, and a series of trays that move the teeth little by little to the target position is designed in advance. The patient switches to the next-stage tray at set intervals, and the tray pushes the teeth to move them bit by bit.
If needed, small bumps (attachments) are bonded to the tooth surface so the tray grips the tooth well, or elastic bands are hooked between the upper and lower teeth. Progress is checked at regular visits, and if the teeth move differently from the plan, the trays are redesigned.
The Korean Association of Orthodontists stresses that, as with conventional bracket appliances, treatment proceeds well only if clear aligners are worn all the time. The advantage that the tray is hard to notice is meaningful only when the wearing time is kept.
How many hours a day must clear aligners be worn?
The Korean Association of Orthodontists recommends wearing them most of the day except for meals and brushing. If the wearing time is short, the teeth do not move as planned, so the next-stage tray no longer fits, and the duration ends up longer.
Times when the tray tends to stay out for long are days with restaurant meals, snacks and frequent coffee. After eating with the tray out, build the habit of brushing, or at least rinsing the mouth, and then putting it back in right away.
For this reason, clear orthodontics is a method in which the patient's cooperation greatly decides the result. If it is hard to keep the wearing time on your own, a fixed appliance may suit better, so be honest about your lifestyle at the consultation.
When are clear aligners hard to use?
The Korean Association of Orthodontists explains that clear aligners cannot treat every malocclusion, and in some cases they are hard to apply. The judgment depends on how far and in which direction the teeth must be moved, whether an extraction space must be closed and whether there is a problem in the jawbone relationship.
That is why, at the diagnosis stage, the type of malocclusion is first checked with radiographs and models. For parts that are hard with clear aligners alone, they are used together with other appliances or mini-screws, or the plan is changed to a fixed appliance.
If you check in advance at the consultation how far clear aligners can go, whether another appliance may be needed midway, and how the cost and duration would change in that case, you can be prepared even if the plan changes during treatment.
Can I use clear aligners sold online?
You should not. The Korean Association of Orthodontists warns that various side effects have been reported with clear aligners sold through online companies and the like, and that they can harm teeth and oral health, so they should never be used.
Before orthodontics, cavities, gum disease, the condition of the tooth roots and the jaw joint must be checked. If teeth are moved without a diagnosis, problems such as gum recession or a disturbed bite may be noticed late. Clear orthodontics too must proceed with a diagnosis at a dental clinic and regular checks on progress.
The Association repeatedly advises that clear aligners are appliances that must be used after an accurate diagnosis at a dental clinic or hospital. If diagnosis and follow-up are skipped because the price is low, correcting a problem when it arises can cost more money and time.
How are clear aligners cared for during treatment?
Each time you take the tray out, rinse it under running water, clean it with a soft brush and put it in its storage case. Avoid hot water, which can deform the tray. A tray wrapped in tissue is easily lost, so always carry the case.
If you drink anything other than water with the tray in, sugar and pigment can collect inside the tray and cause cavities or discoloration. If a tray is lost or broken, do not use a previous or next-stage tray for a long time on your own; contact the dentist and follow instructions.
Brush and floss as usual during clear orthodontics. If the tray is put back on without cleaning the teeth, food and plaque are trapped inside the tray and stay on the tooth surface for a long time.
Common myths and facts
Myth: It is fine if the wearing time of clear aligners is a bit short.
The Korean Association of Orthodontists explains that treatment does not proceed smoothly if the wearing time is insufficient. Cooperation decides the result.
Myth: Clear aligners can be done online without a diagnosis.
Various side effects have been reported with aligners sold online, and the Association warns not to use them. They should be started only after a diagnosis at a dental clinic.
Frequently asked questions
Do clear aligners hurt less than brackets?
According to the Association's explanation, clear trays tend to cause less discomfort than bracket-and-wire appliances. However, right after putting in a new-stage tray, the feeling of teeth being pressed can last for a few days, and it is better to eat soft food then.
Can I eat whatever I like during clear orthodontics?
You take the tray out to eat, so food restrictions are fewer than with fixed appliances. In exchange, you must brush after eating and put it back right away, and if frequent snacking adds up to a lot of time with the tray out, treatment is delayed.
Is the duration shorter with clear aligners?
The duration depends more on the degree of malocclusion and the wearing time than on the type of appliance. If wearing is not kept up, the next-stage tray does not fit and the treatment can actually take longer than planned.
Is a retainer needed after clear orthodontics?
Yes. After teeth are moved, they tend to return to their original positions until the surrounding tissue settles, so wear a retainer as instructed, as with other orthodontics. Do not use the last-stage tray as a retainer on your own.
Does health insurance cover clear aligners too?
Dental orthodontics is non-covered, so clear aligners are also paid for by the patient. Only orthodontics for notified congenital diseases such as cleft lip and palate is an exception and covered, and even then the treatment stage must be pre-registered with the National Health Insurance Service.