Which Factors Determine How Fast Clear Aligners Will Work?

On average, most patients will wear clear aligners for around 12-18 months. While this is shorter than the average time patients wear braces, it is still a significant amount of time. 

There are several factors that determine how quickly Invisalign clear aligners will work, and, unfortunately, they’re not always things you can change. Depending on your unique situation, you may require clear aligners for more or less time than usual. Here are some factors that contribute to the length of your treatment:

Which Factors Determine How Fast Clear Aligners Will Work?

The Complexity of Dental Issues

Some dental issues simply take longer to fix than others, and it’s out of your control. For example, if you have crowded or crooked teeth, an overbite, or another complex issue, treatment will take longer than if you only have a minor gap between your teeth. 

Oral Hygiene Practices

This is something you can control. While you’re using clear aligners, make sure to follow good oral hygiene practices. If you don’t, you may develop cavities or gum disease, and this will slow down your treatment. In some cases, you may have to stop using your clear aligners until the issue has been fixed, and by then, you’ll likely have to start your treatment all over.

Oral hygiene extends to caring for your clear aligners as well. If you don’t take care of them, they may end up breaking or not being able to do their job correctly. In this case, your teeth may not move how your orthodontist plans, and your treatment may be delayed or prolonged.

Patient Compliance

For patients with a sense of discipline, this isn’t an issue. However, for younger patients who may forget to wear their clear aligners, patient compliance can be an issue during treatment. 

During your treatment plan, it’s important that you follow all the instructions that your orthodontist gives you. There will be certain foods you shouldn’t eat, care instructions to follow, and a set schedule for when to change out your aligners. If you are careless about following the instructions or you ignore them, your treatment may take longer, and you may not see the results you want.


This is another factor that you can’t control. Teeth move more for younger patients than adults, so teenagers tend to see faster results. This isn’t necessarily true for everyone, though. Some adults have teeth that move quickly, so their results may be just as quick or faster than younger patients.

Another way that age comes into play is with patient compliance. Again, older patients are typically more disciplined and can better follow care instructions so that their treatment goes smoothly. 

Insufficient Space

During your treatment, your orthodontist may determine that there simply isn’t enough space in your mouth to move your teeth how they should be. In this case, they may recommend an additional treatment to give crowded teeth the space that they need.

Often, orthodontists will recommend interproximal reduction (IPR). This is the process of removing small amounts of enamel on your teeth so that adjacent teeth have the space they need. It allows for a little extra space in your mouth so that your aligners can move your teeth accordingly.


After your initial consultation, your orthodontist will be able to provide you with an estimated timeline for your treatment. While this timeline may be prolonged or shortened depending on how your teeth react, it will provide a good idea of just how long you’ll need to use your clear aligners.

A lot can affect how fast your clear aligners work, and some of it will be up to you. By ensuring that you follow all aftercare instructions and take good care of your clear aligners, your treatment will likely go faster as you’re able to stay on track and achieve the results you want. 

Author: Dr. Alan Wong
Dr. Alan Wong is a dedicated orthodontist who loves helping his patients achieve healthy, beautiful smiles. He is committed to providing gentle, effective care in a patient-centered environment. Dr. Wong is also a strong believer in continuing education, so he can provide his patients with the latest and greatest treatment options.