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Does Wearing an Invisalign Cause a Lisp?

Patients frequently inquire whether using Invisalign may lead them to lisp. In this post, our Ontario dentists explain how and why your clear aligners might affect the way you speak at the start of treatment.

Invisalign is not likely to cause a lisp or other speech impairment, despite the fact that using any orthodontic appliance has the potential to impair your ability to communicate effectively at first.

When you first start wearing your Invisalign aligners, you may notice a tiny lisp, but it will likely only be noticeable to you, is usually transitory, and can be rectified if it continues.

Why do some patients experience a lisp?

Lisps are produced by incorrect tongue positioning within the mouth when speaking, which disrupts airflow and causes some words to sound different when uttered. A lisp is a speech disorder in which the –s and –z consonants are mispronounced as "th" or "l," respectively.

Because the aligners change the space within the mouth, some Invisalign patients acquire lisps when they first start wearing their aligners. They also cause the tongue to travel differently around the teeth, affecting pronunciation. The changes and consequences are usually minor, although some people may require more time to adjust.

Invisalign lisps can also be caused by ill-fitting trays. Each tray is a transparent plastic mould that should fit securely over the teeth. However, because the purpose is to modify the tooth placement, the moulds are constructed to meet the desired tooth positioning for that phase of treatment.

Because the shape and thickness of each set of aligners are similar, most Invisalign patients do not acquire lisps with each new set. However, if a tray is not appropriately formed or positioned, it might induce a lisp. If you believe this to be the case, it's important to contact your Ontario dentist to make sure your Invisalign Clear Aligners are the correct size.

How long will a lisp last?

Each patient is unique, but lisps tend to disappear within a few weeks of the start of treatment. Some folks even acclimate in a matter of hours or days! If a lisp develops, it should gradually fade as the tongue adapts to the aligners and adjusts properly.

Adjusting to your new Invisalign Clear Aligners

Continuing to talk can help prevent or correct a lisp caused by Invisalign. When the tongue adapts to the orthodontia, a lisp tends to disappear. The more a person speaks, the faster the tongue will learn how to navigate around the aligners to make sounds.

If you're concerned about your speech during a public speaking event or a meeting, simply take out your aligners. Invisalign aligners can be removed temporarily throughout treatment. The aligners must be removed when eating and can be removed at other times as needed. (Just be sure you wear them for at least 20-22 hours every day for them to work their magic).

To overcome a lisp and to feel more at ease with your aligners, try reading aloud to yourself or conversing with family and friends whom you trust.

During the adjustment phase, it is typical to experience a minor lisp while the mouth and tongue re-learn how to form the right shapes for each syllable while wearing the aligners. Contact the prescribing dentist or orthodontist if the lisp occurs after starting Invisalign treatment and does not go away within a few weeks. There might be an issue with the mould's fit or positioning.

Curious about Invisalign Clear Aligners? Contact our Ontario dentists for a consultation.

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Since 2001, Toothworks Dental Clinics have been providing patients of all ages with personalized dental care and a welcoming experience at locations across Ontario.

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