Understanding Lisps: Types, Treatment, and Practical Home Strategies

Learn about the different types of lisps, when to seek treatment, and effective strategies to help your child with /s/ and /z/ sounds

What Is a Lisp?

Have you noticed your child saying “yeth” instead of “yes” or making “slushy” sounds when trying to say words with “s” sounds? Your child might have what speech therapists call a lisp.

A lisp refers to difficulty producing the /s/ and /z/ sounds due to incorrect tongue placement. When a person has a lisp, the tongue may stick out between the front teeth or the sides of the tongue may not be positioned correctly in the mouth. Both scenarios result in distorted speech sounds that can affect clarity and confidence.

This guide will help you understand what causes a lisp, the different types, and effective strategies to help your child.

Types of Lisps: Understanding the Differences

There are two main types of lisps, each with distinct characteristics:

Frontal (Interdental) Lisp

A frontal lisp occurs when the tongue protrudes between the front teeth during speech. This positioning causes /s/ and /z/ sounds to be produced more like “th” sounds.

How it sounds:

“Yes” sounds like “yeth”
“Soup” might sound like “thoup”
“Zebra” might sound like “thebra”

This type of lisp is fairly common in young children and is often developmental, meaning many children will naturally outgrow it as their speech develops.

Lateral Lisp

A lateral lisp occurs when air escapes over the sides of the tongue rather than being directed forward through the center of the mouth. This creates a “wet” or “slushy” quality to the /s/ and /z/ sounds.

How it sounds:

The /s/ sounds wet or slushy
You might hear saliva sounds during speech
The sound has a distinctive quality often described as “slobbery”

Unlike the frontal lisp, a lateral lisp is not typically part of normal speech development and usually requires intervention to correct.

When Should Treatment Begin?

Parents often wonder if their child’s lisp is something to be concerned about or if they’ll simply outgrow it. The answer depends on the type of lisp and the child’s age.

For Frontal Lisps

A frontal lisp is considered a developmental speech error in young children. Many children naturally produce this pattern during early speech development and correct it on their own as they mature.

Treatment timeline:

Speech therapists often recommend waiting until a child is around 7-8 years old before providing intervention for a frontal lisp
This gives children time to naturally develop correct production patterns
If the lisp persists beyond this age, therapy is typically recommended

For Lateral Lisps

A lateral lisp is not considered developmental, meaning it’s not an expected part of typical speech development.

Treatment timeline:

Intervention can begin around 4.5 years of age
Earlier intervention is recommended because lateral lisps rarely resolve on their own
Speech therapy is typically more successful when started earlier

If you’re unsure whether your child’s speech patterns warrant concern, consulting with a speech-language pathologist for an evaluation is the best course of action.

Effective Strategies for Helping a Child with a Lisp

Whether your child is currently in speech therapy or you’re looking for ways to support their speech development at home, these practical strategies can help correct lisping patterns.

Strategies for Frontal Lisps

Try these simple techniques to help a child who is protruding their tongue during /s/ and /z/ sounds:

1. The “Bite, Smile, and Blow” Technique

This simple verbal cue helps position the tongue correctly:

Ask your child to gently bite down on their back teeth
Have them smile wide
Then direct them to blow air through their teeth
This naturally positions the tongue behind the teeth where it belongs for correct /s/ production

2. The “Long T” Method

This technique helps children find the correct tongue placement:

Have your child say the /t/ sound and hold it
Direct them to blow more air through the /t/ sound
This should produce a sound similar to /s/
The technique helps them feel where the tongue should be positioned

3. The “Sound Switching” Exercise

This builds awareness of tongue tip placement:

Have your child practice saying “th-s-th-s-th-s-th-s” in one long breath
This helps them feel the difference between the “th” position (tongue between teeth) and the correct /s/ position (tongue behind teeth)
Practice this daily in short, playful sessions

Strategies for Lateral Lisps

These techniques focus on directing airflow correctly for children with “slushy” /s/ sounds:

1. The Visual Airflow Exercise

This helps children visualize and direct their airstream:

Have your child hold a feather, thin strip of paper, or place a finger in front of the center of their mouth
Ask them to try blowing air forward to move the feather/paper
Guide them to lower their tongue tip slightly while maintaining the forward airflow
The goal is to feel air coming out the front of the mouth rather than the sides

2. The Straw Technique

This provides a physical guide for airflow:

Have your child place a straw between their teeth
Direct them to blow air through the straw
This naturally channels the airflow forward
Gradually transition to making an /s/ sound while maintaining that forward airflow

3. The “T to S” Transition

This builds on existing speech sounds:

Ask your child to make rapid productions of /t/: “t, t, t, t, t”
Have them hold and extend the final /t/ into an /s/ sound: “t, t, t, t, tsssss”
This helps transition from a sound they can produce correctly to the target sound

4. The String Visualization

This creates a mental image for correct airflow:

Have your child pretend they’re pulling a piece of string straight out from the front of their mouth
As they “pull” the imaginary string, ask them to make the /s/ sound
This helps direct airflow through the front of the mouth rather than the sides

Making Practice Fun and Effective

Regardless of which techniques you’re using, these principles will help make practice more successful:

Keep Sessions Short and Positive

Aim for 5-10 minutes of practice, 2-3 times daily
Always end on a successful note
Use plenty of praise and encouragement
Never shame or criticize speech errors

Incorporate Games

Play “I Spy” with items beginning with /s/ sounds
Create a treasure hunt for objects with /s/ in their names
Use favorite toys or characters in practice
Award points or small prizes for successful productions

Use Visual Feedback

Practice in front of a mirror so your child can see tongue placement
Record and playback successful attempts
Use smartphone video to show correct vs. incorrect productions
Draw simple pictures of correct tongue placement

Build on Success

Start with isolated sounds (/s/ by itself)
Progress to syllables (sa, se, si, so, su)
Move to simple words (see, sun, sock)
Advance to phrases and sentences
Finally, work on conversational speech

When to Consult a Professional

While the strategies in this article can be helpful, they work best as a complement to professional speech therapy. Consider consulting a speech-language pathologist if:

Your child shows frustration or embarrassment about their speech
The lisp persists beyond the typical developmental timeline
Your child avoids saying certain words or speaking in some situations
You notice other speech or language concerns
Home practice isn’t yielding improvements over time

Frequently Asked Questions About Lisps

Will my child outgrow their lisp?

Many children will naturally outgrow a frontal lisp by age 7-8. Lateral lisps, however, typically require intervention. Each child develops at their own pace, so consulting with a speech-language pathologist is the best way to determine if intervention is needed.

Can a retainer or other dental appliance help correct a lisp?

While some dental appliances may help in specific cases (particularly when the lisp is related to dental structure), most lisps are best treated through speech therapy. A speech-language pathologist may work with an orthodontist in some cases for a comprehensive approach.

Does a lisp affect reading and spelling?

In some cases, yes. Children who consistently misarticulate sounds may have difficulty with phonological awareness skills that are important for reading and spelling. Early intervention can help prevent these secondary impacts.

Can adults correct a lisp?

Absolutely! While it’s often easier to correct speech patterns in childhood, adults can successfully improve their articulation through speech therapy. The techniques are similar, though adults may progress more quickly due to their higher motivation and cognitive abilities.

Are lisps hereditary?

There can be a genetic component to speech sound disorders, including lisps. If parents or other family members had similar speech patterns, a child may be more likely to develop a lisp. However, environmental factors and individual development also play significant roles.

Will braces cause or worsen a lisp?

Some children temporarily develop a lisp when they first get braces due to the physical changes in their mouth. This typically resolves as they adjust to the braces. If a lisp persists for more than a few weeks after getting braces, consulting with a speech-language pathologist is recommended.

Conclusion

A lisp is a common speech sound error that affects many children and some adults. Understanding the type of lisp and appropriate timeline for intervention can help you make informed decisions about your child’s speech development.

With the right strategies and support, most children can significantly improve their production of /s/ and /z/ sounds. Whether you’re working with a speech-language pathologist or supporting your child’s speech at home, consistency and positive reinforcement are key to success.