What is an attachment in clear aligner treatment?
Clear aligner treatment moves the teeth step by step with thin aligners that are made for you and replaced in sequence; Cleveland Clinic says each aligner is generally replaced with a new one every two weeks. On some teeth, the aligner cannot grip a smooth tooth surface well enough, and this is where attachments come in. According to a systematic review by Nucera and colleagues, published in 2022, an attachment is a small bump of composite material that is bonded to the tooth surface and hardened. Composite is the resin-based material also used for tooth-coloured fillings.
Attachments come in different shapes, such as rectangular, bevelled rectangular or oval. Valeri and colleagues (2022) describe attachments as key auxiliaries of aligner treatment and compare them to the brackets used in fixed braces: conventional rectangular and oval attachments help the aligner stay in place, while attachments designed in other shapes are used to produce specific tooth movements.
Cleveland Clinic also lists placing tiny attachments on the teeth as one of the steps of clear aligner treatment, helping the aligners move the teeth.
What do attachments do?
Attachments have two main jobs: helping the aligner fit tightly on the tooth, and determining where and in which direction force is applied to the tooth. According to the systematic review by Jedliński and colleagues, published in 2023, attachments increase the contact area between the aligner and the tooth and allow better control of tooth movement. The review concludes that using attachments clearly improves both how well the planned movement is achieved and how well the aligner stays in place.
Their effect is not the same for every type of movement. The findings of the review by Nucera and colleagues can be summarised as follows:
| Tooth movement | What the research shows |
|---|---|
| Correcting the root angle of front teeth (torque) | Attachments and bumps built into the aligner may help, but they are not always enough to control the root |
| Keeping back teeth stable as anchorage | Bonding more attachments to the back teeth may improve anchorage |
| Rotating a tooth around its own axis | Results are conflicting; some studies found no difference between groups with and without attachments |
| Lengthening (extrusion) or pushing a tooth in (intrusion) | Intrusion seems to improve, but the evidence for both movements is insufficient |
| Moving a tooth bodily | Attachments may improve effectiveness, but the clinical importance of the difference is unclear |
These findings need to be read with care. The review by Nucera and colleagues included only five clinical studies and rated the level of evidence as low. Most of the 26 studies in the review by Jedliński and colleagues were computer models and laboratory studies; according to the authors, the clinical studies could not be blinded, and the quality of the evidence remained limited.
Does every patient need attachments?
No. The number, shape and position of attachments are decided when the treatment is planned, according to which tooth has to move and in which direction. The review by Nucera and colleagues set out to find the most suitable shape, size, number and position for each movement. According to the review by Jedliński and colleagues, for difficult movements such as lengthening the front teeth or rotating a canine, it is recommended to place attachments on all the side teeth from the canine to the second premolar. One study described in the same review found that rotating a premolar without attachments was less efficient.
Attachments are not the only auxiliary used in aligner treatment. The British Orthodontic Society (BOS) says some crowding can be corrected by slightly reducing the width of the teeth (interproximal reduction), and the American Association of Orthodontists (AAO) describes elastics, which are used to apply additional force to the teeth. Whether any of these is needed is also decided during planning.
How are attachments bonded?
Describing the start of treatment, the AAO mentions the initial scans and fitting attachments among the first steps. Attachments are usually bonded before the first aligners are handed over. As Valeri and colleagues describe, a template aligner is used: the spaces in the template that correspond to the attachments are filled with composite, the template is seated on the teeth and the material is hardened with a special light. Because the attachment is bonded to the surface of the tooth, the tooth is not drilled.
According to the laboratory studies in the review by Jedliński and colleagues, the stiffness of the template and the type of composite can affect how closely the attachment matches its planned shape and how much excess material is left around its edges. If you have a crown or a porcelain restoration, mention it at your examination, because bonding to these surfaces requires a different preparation.
Cleveland Clinic says aligners can feel uncomfortable, especially when you first start wearing each new one; the pressure or soreness usually eases within a few days.
What happens if an attachment comes off or wears down?
Attachments can come off or wear down during treatment. The studies described in the review by Jedliński and colleagues found that how often attachments came off, and how much they wore, varied with the material and method used. The authors note that better transfer of force from the aligner to the tooth also puts more load on the bond between the attachment and the tooth.
Because an attachment is one of the points where the aligner grips the tooth, the aligner may not fit as well once it has come off. Cleveland Clinic advises contacting your orthodontist if the aligner feels loose or does not fit. So if you notice that an attachment has come off or is clearly worn, let the clinic treating you know without waiting for your next check-up, and ask how to continue wearing your aligners in the meantime.
How often are check-ups needed during aligner treatment?
Aligners are changed every week or two at home, but treatment is still supervised. The AAO says visits to pick up new aligners or adjust braces are typically scheduled every six to ten weeks, and Cleveland Clinic says your orthodontist schedules follow-up appointments to check that the aligners fit well and are working.
If you live outside Türkiye, this is worth planning before treatment starts. Ask how often you would need to come back, how new aligners would reach you and what would happen if an attachment came off between visits. The AAO also recommends continuing to see your family dentist for regular cleanings during treatment, which can usually be done by your dentist at home.
How do you clean teeth with attachments?
According to Cleveland Clinic, aligners are taken out when you brush and floss. The AAO warns that aligners can trap liquids and food particles against the teeth, increasing the risk of tooth decay and gum disease, so the teeth should be brushed thoroughly after eating or drinking before the aligners go back in. Because attachments form small bumps on the tooth surface, take care not to miss their edges when brushing. The AAO also advises drinking nothing but water while the aligners are in; liquid trapped between the aligner and the teeth can stain both and can cause decay.
How are attachments removed at the end of treatment?
When active treatment ends, the attachments are removed from the tooth surface with finishing and polishing instruments. A very small amount of enamel can be lost in the process. A laboratory study on 70 extracted premolars (Nguyen and Nguyen, 2025) compared seven different removal instruments. With most instruments, the enamel loss stayed between about one hundredth and four hundredths of a millimetre, but with one abrasive stone bur it rose to about 0.1 millimetre and left a rougher surface. The authors recommended not using that bur to remove attachments. This was a laboratory study and does not fully reflect conditions in the mouth, but it shows that choosing a suitable instrument matters for protecting the enamel.
Removing the attachments is not the end of treatment. According to BOS, retainers are needed after any aligner treatment so that the teeth keep their corrected positions.
How are clear aligner treatment and attachments planned at Rönesans?
Orthodontics is one of our clinic’s departments, and this includes clear aligner treatment. Whether aligners suit you is decided at the examination, after your teeth, jaws and bite have been assessed; if they do not, other orthodontic options are discussed. The impressions needed for planning can be taken with an intraoral scanner, without impression paste. Whether attachments are needed, how many and on which teeth is decided by the dentist according to the planned tooth movements.
If treatment is needed, we give you a written treatment and cost plan showing the procedures and the unit and total costs, and you know from the start which dentist will look after you. The cost is confirmed after the examination, based on your treatment plan. Follow-up after treatment runs as a defined process at our clinic. We are open Monday to Friday from 10:00 to 22:00 and on Saturday from 10:00 to 19:00, Türkiye time. If an attachment comes off or your aligner no longer fits your teeth, you can message us on WhatsApp; we answer messages in English and German within 15 minutes during opening hours.
Orthodontic treatment takes months, so if you live outside Türkiye, ask us how check-ups would work before you decide. You can send photos and X-rays on WhatsApp for a preliminary assessment or write to us through our contact page. Our smile makeover page explains how orthodontics can be combined with other aesthetic treatments.