Can Braces Cause a Lisp & How to Adjust Your Speech

Braces can absolutely cause a lisp, and the effect is well documented. A systematic review of orthodontic appliance studies found that fixed braces, clear aligners, retainers, and palatal expanders all have the potential to distort speech, with sibilant sounds like “s” and “z” taking the biggest hit.¹ The good news is that the effect is almost always temporary, though how long it lasts and how much it bothers you depends on the type of appliance, your individual anatomy, and how actively you work to retrain your tongue.

Which Sounds Get Distorted

Your tongue is remarkably precise. When you say an “s” or “z,” the tip hovers just behind your upper front teeth, directing a narrow stream of air through a tiny gap. Even a millimeter of disruption to that space changes the acoustics. That is why sibilant sounds are the first casualties when braces enter the picture. Research consistently identifies the “s” sound as the most commonly and most persistently affected by orthodontic appliances.² The “z,” “sh,” “ch,” and “th” sounds are also frequently distorted, though usually to a lesser degree.³

It is not just consonants, either. The vowels “ee,” “ah,” and “eh” can shift in quality because appliances alter the resonant space inside the mouth. One study on palatal expanders found that the “ee” vowel became “centralized,” meaning it drifted toward a more neutral, muddier sound after the device was placed, then gradually returned to normal over time.⁴ Still, vowel changes tend to be subtle enough that other people rarely notice them. The lisp on sibilants is what people actually hear, and what patients tend to worry about.

How Different Appliances Compare

Not all orthodontic hardware affects speech the same way. The type of appliance you wear makes a real difference in how noticeable the lisp is, how long it sticks around, and which sounds give you the most trouble.

Traditional Labial Braces

Standard metal or ceramic brackets bonded to the front of your teeth are, somewhat surprisingly, among the gentler options for speech. They do add bulk to the tooth surface that faces your lips and cheeks, which can feel awkward and occasionally muddy a consonant. But because they leave the tongue side of the teeth mostly untouched, the tongue’s fine motor work remains relatively unobstructed. Most people with labial braces notice some speech clumsiness in the first few days, then adapt quickly.

Lingual Braces

Lingual brackets, bonded to the inside (tongue-facing) surface of the teeth, are a different story. They sit right where the tongue needs to make contact for sounds like “t,” “d,” “l,” “s,” and “n.” That direct interference tends to cause more significant speech changes than labial braces. A review of lingual appliances noted that thinner bracket designs have helped reduce the impact on speech and comfort, which is one reason manufacturers have steadily shrunk their profiles over the years.⁵ Even so, lingual braces consistently produce more speech difficulty than labial braces or clear aligners.³

Clear Aligners

Aligners like Invisalign cover the entire biting surface and wrap around the teeth, which means they change the oral landscape in a different way than brackets and wires. A systematic review of seven studies found that over half of aligner patients reported speech difficulty, with some studies putting the figure as high as 85 percent.⁶ Patients reported slurring, lisping, and even nasality. The sibilant sounds “s” and “z” were again the primary culprits, while “sh” and “ch” were less affected.

An interesting wrinkle is that acoustic analysis showed aligner patients and fixed-braces patients had similar levels of measurable speech distortion, yet the aligner group perceived their speech as worse, especially right after insertion.⁶ This may have to do with the aligner covering so much of the palate and teeth that the speaker feels the difference more acutely, even when listeners cannot tell. Over time, acoustic measurements showed aligner patients’ speech did improve, but statistically significant changes persisted longer than with fixed appliances.⁷

Palatal Expanders

Rapid palatal expanders are bulky devices that sit across the roof of the mouth, and they represent perhaps the most dramatic short-term disruption to speech. They physically block the tongue from making full contact with the palate, which is needed for a wide range of sounds. Despite that, one study found that all the speech problems caused by a palatal expander were mild and resolved within the first week of wear.⁸ Acoustic analysis from another study confirmed that once the expander was removed, fricative distortion and vowel changes returned fully to baseline.⁴

How Long the Lisp Typically Lasts

Most speech distortion fades within the first few weeks. Your tongue is remarkably good at compensatory learning: it recalibrates to the new terrain in your mouth and finds slightly modified positions that produce acceptable sounds. This process happens largely below conscious awareness, though deliberate practice can speed it along.

The stubborn exception is the “s” sound. Because producing a clean “s” requires such fine motor precision, it is the last sound to fully recover. A systematic review found that while most speech impairments returned to normal within weeks, distortion of the “s” sound could persist for more than three months with some appliances.¹ That timeline can feel long when you are self-conscious about how you sound at work or in social situations. But even in the worst cases, the distortion is transient: once the appliance is removed, or once the tongue fully adapts, normal speech returns.

There is also a difference between what you hear and what others hear. Several studies noted that patients perceived their own speech changes as much more severe than listeners rated them. If you are fixating on a slight whistle in your “s,” there is a decent chance the person you are talking to does not notice it at all.

Practical Ways to Speed Up Adaptation

The tongue does most of its adaptation on its own, but you can help the process along. None of these techniques require a specialist, and all of them are free.

Read aloud daily: Pick any book, article, or script, and read it out loud for ten to fifteen minutes a day. This forces your tongue to cycle through a wide range of sounds and positions, accelerating the motor learning that happens naturally. Focus on passages with plenty of “s” words.
Slow down deliberately: Speaking quickly amplifies the lisp because you are giving your tongue less time to find its modified positions. In the first couple of weeks especially, consciously slowing your pace gives your tongue the extra milliseconds it needs.
Practice tongue-tip placement: For sibilants like “s” and “z,” experiment with where your tongue tip sits relative to the brackets or aligner. You may need to position it slightly differently than before. Repeat words like “six,” “seize,” “suppose,” and “scissors” until you find a position that sounds clean.
Record and listen back: Your perception of your own speech through bone conduction is unreliable, and anxiety tends to magnify the problem. Record yourself on your phone and listen back. You may discover the lisp is far less noticeable than it feels from the inside.
Stay hydrated: Braces and aligners both tend to increase saliva production initially, which can create a wet, slushy quality on sibilants. Swallowing frequently and sipping water can help manage the excess.

For clear aligner wearers specifically, wearing the aligners as much as possible, including during low-stakes conversations at home, gives the tongue more adaptation time. Taking aligners out for important calls or presentations is tempting, but it resets the clock each time. The more continuous wear your mouth gets, the faster it adjusts.

The Emotional Toll of Speaking Differently

A lisp from braces might be physically minor, but it can land hard psychologically, especially for adults. A qualitative study of adult orthodontic patients found that speech changes directly affected self-esteem and confidence. Participants described hiding their smiles, struggling through phone calls, and dreading meetings with new people.⁹ One participant, a receptionist, described being fitted with braces and immediately having to answer phones at work with a noticeable lisp. Another, a veterinary specialist, said she felt “vulnerable” and “really stupid” in meetings with management because of her altered speech.

The COVID-era shift to video calls made things worse for some patients, who felt that being on camera magnified every speech imperfection. One participant described hiding her mouth during video calls because she felt self-conscious about drooling.⁹ These experiences are worth acknowledging because they are common and because knowing they are common can itself be reassuring. You are not uniquely struggling; this is a well-documented part of wearing braces as an adult.

That said, patients who had worn braces previously as children seemed to handle the lisp with less anxiety, likely because they remembered the adaptation period and trusted it would pass. As one participant put it: “When I got the braces, I was actually lisping quite a bit. I think because I had it as a kid, and I knew it will take a little bit of time to get used to it; so, I did not have any concerns about that.”⁹ If this is your first time, borrowing that confidence is probably the single best thing you can do: the lisp will pass.

When Speech Problems Persist

In rare cases, speech issues do not resolve on their own within the expected timeline. This is more likely with complex treatment plans that significantly alter bite alignment or jaw position, particularly those involving surgery. A study of patients who underwent combined orthodontic-surgical treatment for jaw misalignment found articulatory disorders in a subset of patients. Of those who completed speech therapy, most achieved full normalization, though a few saw only partial improvement.¹⁰

If you still have a noticeable lisp more than three months into treatment, it is worth raising the issue with your orthodontist. Sometimes a small adjustment to a wire, bracket, or aligner attachment can eliminate the contact point that is tripping your tongue. In other cases, a few sessions with a speech-language pathologist can help you consciously retrain the motor patterns that your tongue has not figured out on its own. Speech therapy for braces-related issues is not a long-term commitment for most people; it is more like a handful of focused sessions to troubleshoot specific sounds.

There is also an emerging category of appliances designed specifically to retrain tongue posture. Newer devices like clear tongue cribs and tongue cage appliances aim to correct habits such as tongue thrusting, which can both contribute to orthodontic problems and make speech adaptation harder during treatment. Clinical use of these devices has shown improvements in tongue positioning and speech clarity, though they remain a niche tool rather than a standard part of treatment.¹¹

Choosing an Appliance With Speech in Mind

If you have not yet started treatment and speech clarity matters a great deal to you, whether because of your job, public speaking commitments, or personal comfort, the choice of appliance is worth discussing with your orthodontist explicitly. Based on the available evidence, the rough hierarchy from least to most speech disruption looks like this:

Labial (front-facing) braces: Least speech impact overall. The tongue has room to work, and adaptation is fastest for most people.
Clear aligners: Comparable measurable distortion to labial braces, but patients tend to perceive the disruption as worse, and the “s” sound can take longer to normalize. On the plus side, you can remove them for a critical presentation or interview.
Lingual braces: Most speech disruption among the common options, because brackets sit right where the tongue needs to articulate. Thinner modern designs help, but lingual patients should expect a longer and more noticeable adjustment period.

Palatal expanders are in their own category since they are not typically chosen instead of braces but rather used alongside them for a limited period. Their speech impact is real but brief, usually resolving within a week.

Of course, speech impact is only one factor in the decision. Treatment effectiveness, cost, aesthetics, and your specific dental needs all matter. But if your orthodontist gives you a genuine choice between two equally effective options and one of them is less likely to affect your speech, that is useful information to have. Too many patients only learn about the speech implications after the appliance is already bonded in place.

Braces and Pre-Existing Lisps

A separate concern is what happens when someone already has a lisp or speech issue before braces go on. This is more common than many people realize, especially with interdental lisps, where the tongue pushes forward between the teeth during “s” and “z” sounds. In these cases, the relationship between braces and speech goes both ways. The orthodontic treatment is often correcting the very tooth positioning or bite alignment that contributed to the lisp in the first place. So while braces may temporarily make the lisp more pronounced, the end result of treatment can actually improve it.

Tongue thrusting habits, where the tongue pushes against or between the front teeth during swallowing and speaking, complicate matters further. If a tongue thrust is not addressed, it can undermine orthodontic results and perpetuate speech issues even after braces come off. This is one area where a speech-language pathologist can add genuine value alongside orthodontic treatment, working to retrain the tongue’s resting position and swallowing pattern while the teeth are being moved into their new alignment.

If you or your child had a lisp before starting treatment, mention it to the orthodontist at the consultation. It does not change the fundamental plan in most cases, but it helps set realistic expectations about what the speech adjustment period will look like and whether concurrent speech therapy would be beneficial.

1
European Journal of Orthodontics. Speech and orthodontic appliances: a systematic literature review
2
PubMed Central. Effects of fixed labial orthodontic appliances on speech sound production
3
Evidence-Based Dentistry. Impact of clear aligner therapy on speech: does clear aligner therapy cause any speech difficulty?
4
PubMed. Impact of a rapid palatal expander on speech articulation
5
PubMed. Speech and discomfort during lingual orthodontic treatment
6
European Journal of Orthodontics. The effect of clear aligners on speech: a systematic review
7
PubMed Central. Speech performance in adult patients undergoing Invisalign treatment
8
American Journal of Orthodontics and Dentofacial Orthopedics. Influence of palatal expanders on oral comfort, speech, and mastication
9
American Journal of Orthodontics and Dentofacial Orthopedics. Adult orthodontics, motivations for treatment, choice, and impact of appliances: A qualitative study
10
PubMed. Myofunctional and speech rehabilitation after orthodontic-surgical treatment of dento-maxillofacial dysgnathia
11
PubMed Central. Tongue Retraining Appliance: Clear Tongue Crib and Clear Tongue Cage Appliance