Clear Aligner Treatment: What It Is and Who It Suits

What Is Clear Aligner Treatment?

Clear aligner treatment is an orthodontic method that uses a series of custom-made, transparent and removable aligners instead of brackets and wires to correct the position of the teeth. It is also known informally as "invisible braces". Each aligner is made to move the teeth by very small amounts in the planned direction; by moving on to the next aligner at set intervals, the teeth are gradually brought into the desired position.

The term "clear plate" is sometimes also used for the protective night guard worn against clenching and grinding. These are two different appliances; the difference is explained separately below.

When Can Clear Aligners Be Used?

Suitability varies from person to person and is determined by an orthodontic examination. In general, they may be considered for:

• Mild to moderate crowding (teeth lined up too tightly)
• Gaps between the teeth
• Teeth shifting again (relapse) in people who have had orthodontic treatment before
• Some mild bite problems

Are they suitable for every case?

No. Severe crowding, skeletal problems caused by the position of the jaws relative to each other, and cases where some teeth need to be rotated a great deal or moved vertically may require fixed orthodontic treatment or other approaches. In addition, because wearing the aligners for enough hours each day is an essential part of treatment, they may not be a suitable option for people who cannot follow the wear rules.

How Does the Treatment Proceed?

• Examination and records: An intraoral examination is carried out, X-rays and photographs are taken and the health of the teeth and gums is assessed.
• Digital impression: The teeth are scanned with an intraoral scanner to create a three-dimensional digital model.
• Planning: How the teeth will move step by step is planned on the computer. The aligners are produced after the plan has been checked and approved by the dentist.
• Attachments: Small tooth-coloured composite bumps may be bonded to some teeth so that the aligner grips them better; they are removed when treatment ends.
• Aligner changes and check-ups: Aligners are changed at intervals set by the dentist, and progress is monitored with regular check-ups.
• Retention: At the end of treatment, a fixed wire or a removable retainer is used to stop the teeth returning to their old positions.

Treatment time varies with the type of problem being corrected and how consistently the aligners are worn; it can range from a few months to more than a year. The exact duration can only be estimated after examination and planning.

Wear and Care

• Aligners are usually worn 20–22 hours a day and removed only for eating and brushing.
• It is advisable to drink nothing but water while wearing them; sugary or coloured drinks can collect under the aligner and lead to decay and staining.
• After eating, the teeth are brushed and the spaces between them cleaned before the aligner is put back in.
• Aligners are cleaned with lukewarm (not hot) water and a soft brush; hot water can distort them.
• When removed, aligners should be kept in their case; aligners wrapped in a napkin are often lost.

When moving to a new aligner, feeling pressure and mild aching in the teeth for the first day or two is normal. Speech may lisp briefly; people usually adjust within a few days.

When Should You Contact Your Dentist During Treatment?

• If an aligner breaks, cracks or is lost (the dentist may advise using the previous or next aligner until a new one is made)
• If the aligner does not seat on the teeth or its edges stand away from them
• If the edge of the aligner injures the gum or cheek
• Pain lasting more than a few days or steadily increasing
• Marked looseness of a tooth, or swelling or bleeding of the gums
• If one of the attachments bonded to the teeth comes off

Regular dental check-ups and scaling should also continue during treatment, so that decay and gum problems under the aligners are noticed early.

Clear Aligners or Fixed Braces?

Clear aligners are less visible and can be removed for eating and brushing, which makes oral hygiene easier. On the other hand, their success depends largely on the patient wearing them consistently. Fixed braces work independently of the patient's compliance and may be preferred for more complex tooth movements. Which is suitable depends on the type of problem and is decided by an orthodontic assessment.

How Clear Aligners Differ from a Night Guard

A night guard (protective splint) does not move the teeth. It is used in people who clench and grind in their sleep to protect the teeth from wear and fracture and to help reduce the load on the jaw muscles and joint. Orthodontic clear aligners, by contrast, are designed to change the position of the teeth and are used as a sequential set. Information on night guards is on the teeth clenching treatment page.

Other Options for Small Gaps

If a small gap between the front teeth is purely a cosmetic concern and there is no other problem with the position of the teeth, closing the gap with composite instead of moving the teeth is also among the options. Which route is suitable depends on the width of the gap, the size of the teeth and the bite. Details are explained on the gap closure page.

This article is for general information and does not replace an examination by a dentist. Whether clear aligner treatment is suitable is decided after an orthodontic examination and assessment of the records.