Lisps in Children: Types of Lisp, Causes, and When to Get Help

What is a lisp, and what does it sound like?

A lisp is a difficulty achieving the correct tongue position for the s and z sounds. Speech-language pathologists class it as a functional speech disorder: a difficulty learning to make one or a few specific speech sounds, where functional means the cause is not known. The older name, sigmatism, is no longer used.⁠¹

In most lisps the tongue either pushes between the front teeth or touches them, so s and z sound more like th: “soup” becomes “thoop” and “zoo” becomes “thoo”.⁠¹ For a clear s, the tip of the tongue sits just behind the upper front teeth and the air flows down a narrow groove along the middle of the tongue; each type of lisp is a breakdown in that position or that airflow.⁠⁴

A lisp on its own does not usually make a person hard to understand. Its effect is more on how a child is seen: some children are praised because a lisp sounds cute, while others meet criticism, nagging and teasing.⁠¹

Is a lisp a speech sound disorder?

Yes, of one kind. The American Speech-Language-Hearing Association (ASHA) uses speech sound disorder for any difficulty with perceiving, producing or representing speech sounds, and lists distortions, sounds that are altered or changed such as a lateral s, among the signs. Speech sound disorders with no known cause are called articulation disorders when the difficulty lies in producing sounds and phonological disorders when it lies in the sound system.⁠⁹ A lisp is a difficulty in producing the sound. A child with a phonological disorder can usually make the individual sounds but has trouble organizing them into a system of contrasts, and the two can occur together.⁠¹

What are the four types of lisp?

Speech-language pathologists describe four types, named for where the tongue goes and where the air escapes.⁠^1,4

What is an interdental or frontal lisp?

In an interdental lisp, also called a frontal lisp, the tongue pushes forward between the front teeth and the air is directed forward, so s and z sound like th: “missing” becomes “mithing” and “buzz” becomes “buth”.⁠¹ An NHS children’s speech and language therapy service describes it the same way, with “sock” sounding like “thock”, and calls it common in children until about age 5 and part of typical speech development.⁠²

Why does a lateral lisp sound wet or slushy?

In a lateral lisp, the air escapes over the sides of the tongue instead of down the middle. The tongue sits close to its position for l, and the sound is often called a slushy s; it can sound wet or spitty.⁠¹ Lateral lisps are not found in typical speech development, and the NHS service advises that a child who has one may benefit from a speech and language therapist.⁠^1,2 ASHA’s guidance for clinicians uses the lateral s as its example of a distortion.⁠⁹

What is a dentalized lisp?

In a dentalized lisp, the tongue rests on or pushes against the front teeth without coming between them. The air still goes forward, and the s sounds slightly muffled rather than like a clear th.⁠¹ Dentalized lisp is a description speech-language pathologists use, not a formal diagnosis, and typically developing children can produce dentalized s and z until about age 4½ and then grow out of it.⁠¹

What is a palatal lisp?

In a palatal lisp, the middle of the tongue touches the palate quite far back while the person tries to say s or z. Prolonging an h closely followed by a y gives roughly the sound.⁠¹ Like a lateral lisp, a palatal lisp is not part of typical speech development, and speech-language pathologist Caroline Bowen advises assessment for anyone who has one.⁠¹

Can a lisp affect sh, ch and j as well as s and z?

Yes. Some children and adults who lisp on s and z also have trouble placing the tongue for sh as in “shoe”, zh as in “measure”, ch as in “chair” and j as in “badge”. They may make these sounds against or between the teeth, with air escaping at the sides, or with too much contact against the palate.⁠¹

Which types of lisp are a normal part of speech development?

Only the forward ones. It is a normal developmental phase for some, but not all, children to produce interdental or dentalized s and z until they are about 4½, while neither lateral nor palatal lisps are part of normal development.⁠¹ Speech-language pathologists rarely treat an interdental or dentalized lisp in a child younger than 4½, because it is regarded as normal at that age, but they may assess a younger child to find out whether it is a lisp and what type, and treating a lateral or palatal lisp before 4½ may be appropriate.⁠¹

Do all toddlers have a lisp?

No. Some children go through a phase of interdental or dentalized s and z, and others do not.⁠¹ Toddlers are still early in learning sounds: by age 3, most English-speaking children say m, n, h, w, p, b, t, d, k, g and f in words, and most can say almost all speech sounds correctly by age 4.⁠⁵ In a review of US norms covering 18,907 children, s and z were acquired between 4 years 0 months and 4 years 11 months, the age by which 90% of children produced them correctly, and the th in “thin” not until age 6.⁠³ A review of 64 studies in 27 languages found the same pattern: most consonants acquired by age 5, with fricatives such as s among the later ones.⁠¹²

By what age does a frontal lisp usually go away?

Children developing speech along typical lines may have an interdental lisp until about 4½, after which it disappears; if it does not, an assessment by a speech-language pathologist is indicated.⁠¹ The NHS service gives about age 5 and says most children grow out of lisps when they are ready.⁠² Bowen adds that no studies confirm which types are outgrown, but that most speech-language pathologists expect interdental and dentalized lisps to be outgrown more often than lateral or palatal ones.⁠¹

Some speech errors last longer. Reviewing several sources, Flipsen estimated that 1 to 2% of young adults still have speech sound errors, and that up to 75% of the errors present at the end of the developmental period, around age 9, may resolve on their own by the end of high school; he notes that therapy may still be justified to reduce their social consequences.⁠¹³

How can I tell which type of lisp my child has?

Listen to where the air goes, and watch the tongue in a mirror. These are the signs speech and language therapists describe:⁠^1,2

• Tongue visible between the teeth, s sounds like th: an interdental (frontal) lisp.⁠^1,2
• Tongue against the back of the teeth, s slightly muffled: a dentalized lisp.⁠¹
• A wet, spitty or slushy s, with air escaping at the sides: a lateral lisp.⁠^1,2
• An s made far back in the mouth, close to a prolonged h followed by y: a palatal lisp.⁠¹

Only a speech-language pathologist can confirm the type, and assessing a young child to see whether a difficulty is a lisp, and which kind, is part of their work.⁠¹

Is it a lisp, or a different speech sound problem?

Not every difficulty with s is a lisp. Leaving s and z out (“sun” said as “un”) or replacing them with another consonant (“sun” as “wun”, “so” as “doe”) are not forms of lisping, and children who make these changes may have phonological difficulties.⁠¹ ASHA lists substitutions, omissions, additions and distortions among the signs of a speech sound disorder.⁠⁹ Late talking is a separate topic: delayed speech.

What causes a lisp?

Usually nothing that can be pinned down. A lisp is a functional speech disorder, meaning its cause is not known: the child may have particular difficulty producing the sound, or may have learned to say it the wrong way until the wrong way became a habit.⁠¹ For speech sound disorders with no known cause, ASHA lists risk factors including being male, problems before and around birth, a family history of speech or language difficulties, and persistent fluid in the middle ear.⁠⁹ Several features of the mouth are examined in every assessment, and the evidence differs for each.⁠^6,9

Is tongue thrust linked to a lisp?

Yes, and it is one of the clearer links. Tongue thrust, the tongue pushing forward between the teeth, is one of the orofacial myofunctional disorders: patterns of mouth and face muscle use that put the tongue in the wrong place at rest, in swallowing and in speech. ASHA lists distorted s and z, often with an interdental lisp, among their signs, and notes that children with speech sound disorders are more likely to show a tongue thrust swallow.⁠⁶ Estimates of tongue thrust swallowing in school-aged children range from 5.4% to 62.3%, depending on how it is defined.⁠⁶ Where there is an open bite, ASHA notes that an orthodontist may need to treat it before a speech-language pathologist works on the tongue thrust or the interdental lisp.⁠⁶

Do thumb sucking and pacifiers cause a lisp?

They may contribute, but the evidence is thin and concerns speech in general rather than lisps. In 128 Chilean preschoolers, finger sucking roughly tripled the odds of a speech disorder (odds ratio 2.99), as did pacifier use for 3 years or more (3.42); the study was observational and relied on parents’ recall.⁠⁸ In 100 British children aged 2 to 5, most speech measures were not linked to pacifier use at all; only frequent daytime use was associated with more atypical errors, and not in children older than 38 months, and the authors call the evidence base for any effect very small.⁠¹⁴

The likelier route is through the teeth and tongue. Sucking habits are linked to open bites and crossbites, and ASHA lists chronic sucking habits past age 3 among the factors that can play a part in orofacial myofunctional disorders.⁠^6,8 An NHS service suggests keeping pacifier and bottle use to a minimum during the day for a child who lisps.⁠² The dental side: Pacifier use, teeth, and speech.

How much does tongue tie have to do with a lisp?

Less than many parents expect. ASHA summarizes the research on tongue tie and later speech as conflicting but trending toward minimal to no impact, though one study linked more severe tongue tie with speech sound disorders.⁠⁶ In a 2002 study of 30 children having a tongue tie released, a speech-language pathologist judged articulation problems to be due to the tie in 15 of 21 children assessed. Of 15 reassessed after surgery, 9 had improved articulation, 4 who had normal speech beforehand were unchanged, and 2 still had an articulation disorder; every child had the surgery, so there was no untreated group to compare with.⁠¹⁵ Checking for tongue tie is part of a speech-language pathologist’s examination of the mouth, which is how its role is judged for a particular child.⁠^1,9 More on Tongue ties.

Do teeth and bite affect a lisp?

They can. In 547 Brazilian schoolchildren aged 7 to 13, those with a posterior crossbite were more likely to have speech distortions (prevalence ratio 1.77), and those with an anterior open bite were more likely to have the tongue resting out of place (2.36), while a deep overbite was linked with fewer of both. The distortions the study examined include anterior and lateral lisps.⁠⁷ ASHA describes significant correlations between malocclusion, signs of orofacial myofunctional disorders and speech sound disorders, and the oral examination in a speech assessment includes how the teeth meet.⁠^6,9 Bite problems in young children: Early signs of bite problems.

Can losing front teeth early cause a lisp?

The evidence is mixed, and it comes from children who had upper front baby teeth pulled early rather than from the normal loss of teeth at school age. In 57 children whose upper front baby teeth were extracted between ages 2 and 4, 65% of parents reported trouble with the s sound; on a speech-language pathologist’s assessment, 46% of the children whose parents heard a change had problems with s and z, and none of the others did.⁠¹⁶ A study of 26 children who lost those teeth before age 5 found no difference in articulation at ages 8 to 10 compared with children who lost them normally, and a 2025 case series of three preschoolers found no significant change in speech after extraction.⁠^17,18 ASHA lists early loss of the upper front teeth among the structural differences that can encourage the tongue forward.⁠⁶ How baby teeth and speech relate: baby teeth and speech development.

Can hearing problems affect how a child says s?

Hearing loss can affect speech development, because children learn to talk by listening and imitating, and a hearing check is part of a speech sound assessment for that reason.⁠^5,19 ASHA includes a hearing screening in a comprehensive speech sound assessment and lists persistent middle ear fluid, often with hearing loss, among the risk factors for speech sound disorders; Cleveland Clinic lists frequent middle ear infections too.⁠^9,19

Is mouth breathing linked to a lisp?

Possibly, through where the tongue rests. Bowen notes that when a child makes many sounds with the tongue forward, it can sometimes indicate a constantly blocked nose from allergy, infection or large adenoids, or be associated with habitual mouth breathing, tongue thrust or sucking habits.⁠¹ ASHA cites a study in which about 31% of children with chronic mouth breathing had a speech sound disorder.⁠⁶ Mouth breathing and the teeth: mouth breathing and dental health.

When should a lisp be checked by a speech-language pathologist?

Speech and language therapy sources point to five signals:⁠^1,2

• A wet, slushy or far-back s, at any age. Lateral and palatal lisps should be assessed without delay.⁠¹
• A forward lisp still there after about 4½ to 5. If an interdental or dentalized lisp has not gone by then, an assessment is indicated.⁠^1,2
• Trouble with many sounds, not only s and z. Most children say almost all speech sounds correctly by 4, and by that age parents should understand most of what a child says.⁠^5,19
• A child who is upset about talking. Children with articulation difficulties can become self-conscious and avoid reading aloud, talking to others or saying certain words.⁠¹⁹
• Possible hearing problems or frequent ear infections. Hearing should be checked when a speech sound problem is suspected.⁠^5,9

Young children are usually referred by their parents, often on a preschool teacher’s advice.⁠¹ In US public schools, a speech sound disorder qualifies a child for services under the Individuals with Disabilities Education Act when it adversely affects educational performance or social interaction and the child meets the state’s criteria; a child who does not qualify may still be eligible under Section 504.⁠⁹

What does a speech-language pathologist check in a lisp evaluation?

An assessment covers much more than the s sound. ASHA describes these parts:⁠⁹

1. Case history. The family’s concerns, ear infections, any family history of speech, language or reading difficulties, the languages spoken at home, and how well others understand the child.⁠⁹
2. Mouth examination. How the teeth meet, the structure of the hard and soft palate, and how the lips, jaw and tongue move, including checks for tongue tie and swallowing patterns.⁠^1,9
3. Hearing screening. Done during the assessment if it was not done at screening.⁠⁹
4. Speech sounds. Sounds in single words and in connected speech such as storytelling or conversation, noting the type of each error and where it falls in the word.⁠⁹
5. Stimulability. Whether the child can copy a correct s when shown, which helps predict whether it is likely to come in without therapy and which targets to choose.⁠⁹
6. Perception. Whether the child hears the difference between a correct s and their own version.⁠⁹
7. Language. Screened as well, because language problems often occur alongside speech sound disorders.⁠⁹

The assessment can conclude that speech is typical for the child’s age and community, that a speech sound disorder is present and of what type and severity, or that other professionals should be involved.⁠⁹ An accent or dialect is not a speech sound disorder, and ASHA asks clinicians to judge sounds against the child’s own linguistic community.⁠^5,9

What does speech therapy for a lisp involve?

Treatment for a speech sound disorder runs in three stages: establishment, getting the child to make the sound correctly on purpose; generalization, carrying it into syllables, words, phrases and conversation; and maintenance, making it automatic and teaching the child to notice and correct their own errors.⁠⁹ Most speech-language pathologists treat lisps with traditional articulation therapy or a variation of it.⁠¹

In Bowen’s outline of therapy for an interdental lisp, the clinician first checks that the child hears the difference between s and th, alone and in word pairs such as “sink” and “think”. The child is then taught the new s with touch, listening and movement cues, and practices it alone, in syllables, in words, in phrases, in sentences and finally in conversation, with modeling and praise phased out as the child learns to monitor their own speech. Brief, frequent practice works best.⁠¹

Clinicians use tools that show the child what the tongue is doing: a mirror, hand gestures, ultrasound images of the tongue, palatography that records where the tongue touches the palate, and visual displays of the sound itself.⁠⁹ For lateral and palatal lisps, Bowen names the Butterfly Procedure as one effective technique.⁠¹

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What does the research show about lisp therapy?

The research is small but positive. In a 2013 study of 18 children aged 6 to 11 with dentalized or interdental s and z, the group that had 15 weeks of weekly 10-minute sessions with a speech-language pathologist improved significantly in everyday speech while the untreated group did not change; the second group improved once its treatment began, and most children kept their gains two years later.⁠¹⁰ Ultrasound biofeedback has been studied mostly for the r sound: in a 2019 review, 81% of participants had been treated for r, most studies were small, and the authors saw it as a possible help for errors that persist despite earlier therapy.⁠²⁰ A 2026 meta-analysis of 16 ultrasound studies found large improvements in accuracy, with high variation between studies and signs of publication bias.⁠²¹

How long does therapy for a lisp take?

It varies, and speech-language pathologists disagree on how easy a lisp is to correct and how long that takes. Bowen describes therapy for lisps in young children as usually short-term and successful.⁠¹ In the controlled study, 15 weekly sessions of 10 minutes were enough for a significant change.⁠¹⁰

Do tongue and mouth exercises help a lisp?

Not on the current evidence. A Cochrane review of non-speech oral motor treatment, exercises such as smiling, pursing the lips, blowing horns or bubbles and lip massage, found three small trials with 22 children treated for s and z errors; two found no added benefit over speech therapy alone and the third was reported unclearly, so the review found no strong evidence that the exercises work.⁠¹¹ ASHA asks clinicians to weigh what a given oral motor activity is likely to accomplish and whether it addresses the child’s speech error.⁠⁹ Practicing the s sound itself, with the tongue in the right place, is the core of therapy.⁠^1,9

How can parents help a child with a lisp at home?

NHS speech and language therapy services suggest these steps for a forward lisp:⁠^2,22

• Model the word instead of correcting. If a child says “the blue thock”, reply “here’s your blue sock”; children learn a lot about speech sounds by listening.⁠²
• Play listening games. I Spy with things that start with s and with th helps a child notice the difference, and hearing the difference comes before saying it.⁠^2,22
• Use a mirror. If the child is willing, show how the tongue stays behind the teeth for s.⁠^2,22
• Pick four or five everyday s words. Words such as “sock”, “soap” or “sit down”; talk about the s sound in them, without pressure if the child is not ready to copy.⁠²
• Cut down daytime pacifier and bottle use. An NHS service suggests keeping both to a minimum during the day.⁠²
• Keep practice short. Once the new s is taught, brief and frequent practice with an adult works best, such as 5-minute chats focused on a clear s.⁠^1,22

Two things are worth avoiding. Mouth exercises such as blowing bubbles or lip massage have no strong evidence for speech errors.⁠¹¹ Pressure does not help either: the NHS advice is to let a child have a go at copying only if they are able, and children who struggle with sounds can become self-conscious about speaking.⁠^2,19

Can adults have a lisp, and can it be corrected?

Yes to both. Functional speech disorders such as lisps can persist into adulthood, especially in people who stopped therapy as children or never had it.⁠¹ Flipsen’s review estimates that 1 to 2% of young adults have residual or persistent speech errors, a figure ASHA also cites.⁠^9,13 Some adults are content with their speech; others describe frustration, embarrassment and low self-esteem, and fear it is too late to change.⁠¹

Therapy for adults follows the same lines as for children. Adults are usually very motivated to practice but can find it hard to get someone to give accurate feedback on their homework, which matters as much as it does for a child, and there is no evidence that do-it-yourself programs work.⁠¹ A lisp that appears for the first time in adulthood is a different matter: dysarthria, a motor speech disorder, can follow damage to the nervous system such as a stroke or traumatic brain injury.⁠¹⁹

How can a lisp affect a child socially?

A lisp seldom makes a child hard to understand, but it can shape how others treat them, from being called cute to being teased, nagged or ridiculed.⁠¹ ASHA notes that people whose speech difficulties persist are at risk of low self-esteem and bullying, and that in school a speech sound disorder can affect a child’s willingness to answer questions in class and to talk with friends at lunch and recess.⁠⁹

Frequently Asked Questions

RelatedSpeech therapySpeech delay

Sources

1. Bowen C. Lisping: When /s/ and /z/ are hard to say. speech-language-therapy.com (Caroline Bowen, speech-language pathologist). 2011. Checked October 11, 2026.
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   “A lisp is a Functional Speech Disorder (FSD), and a functional speech disorder is a difficulty learning to make a specific speech sound, or a few specific speech sounds. The word ‘functional’ means that the cause of the disorder is not known.” “Typically, when a person lisps their tongue either protrudes between, or touches, their front teeth and the sound they make is more like a ‘th’ than a /s/ or /z/.” “It is a perfectly normal developmental phase for some (not all) children to produce interdental or dentalised /s/ and /z/ sounds until they are about” four and a half “years of age. On the other hand, neither lateral or palatal lisps are part of the normal developmental progression. The speech of a child with a lateral or palatal lisp should be assessed, by a qualified speech-language pathologist/speech and language therapist, without delay. Both adults and children can be helped by an SLP/SLT, but successful self-help is rarely reported.” Interdental: “the tongue protrudes between the front teeth and the air-flow is directed forwards. The /s/ and /z/ sound like ‘th’”; “‘soup’, ‘missing’ and ‘pass’ ... are pronounced ‘thoop’, ‘mithing’ and ‘path’”. Dentalised: “The tongue rests on, or pushes against, the front teeth, the air-flow is directed forwards, producing a slightly muffled sound.” Lateral: “The tongue position for a lateral lisp is very close to the normal position for /l/ and the sound is made with the air-flow directed over the sides of the tongue”; “A lateral lisp often sounds ‘wet’ or ‘spitty’.” Palatal: “the mid-section of the tongue comes in contact with the soft palate, quite far back”. “Lisping, as an isolated speech characteristic, does not usually reduce the person’s intelligibility unduly.” “Waiting well past” four and a half “is not good advice. The longer the child waits the stronger any ‘habit factor’ will be.” Assessment “examines the anatomy of the mouth and the movements it can make, checking for tongue tie, palate structure and function, swallowing patterns”; “Omitting /s/ and /z/ ... or replacing them with consonants like /w/ or /d/ ... are not forms of lisping.” “Most SLPs/SLTs use a Traditional Articulation Therapy approach”; “Brief, frequent practice periods work best.” “The Butterfly Procedure can be an effective technique for remediating lateral or palatal production”. Adults: “Therapy for adults is along the same lines as therapy for children”; “there is no evidence reported in the research literature that these programs actually work.”
2. Whittington Health NHS Trust, Islington Additional Needs and Disability Service. Lisps. Children’s speech and language therapy advice. Last updated September 10, 2025. Checked October 11, 2026.
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   “We call this an ‘interdental lisp’ because the tongue goes between the front teeth. This type of lisp is common in children until about the age of 5 years and is part of typical speech development.” “There is another type of lisp called a ‘lateral lisp’. This is where you hear the air escaping out the sides of the tongue. This type of lisp is not a part of typical development, and the child may benefit from some support from a Speech and Language Therapist.” Home advice: “Model the adult pronunciation of the word. For example, if your child says ‘I want to wear the blue thock’, you can say ‘Here’s your blue sssock’.”; “Play ‘I Spy’ together”; “Mirror play”; “Choose 4 or 5 simple /s/ words”, “avoid putting too much pressure on them if they are not ready”; “If your child uses a dummy or bottle, try to minimise this during the day.” “most children grow out of lisps when they are ready.”
3. Crowe K, McLeod S. Children’s English Consonant Acquisition in the United States: A Review. American Journal of Speech-Language Pathology. 2020;29(4):2155-2169. PMID 33181047. Checked October 11, 2026.
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   “Fifteen studies (six articles and nine assessments) were included, reporting consonant acquisition of 18,907 children acquiring English in the United States.” “Most consonants were acquired by 5;0 (years;months).” The group that includes s and z was “acquired by 4;0-4;11”, and voiceless th (as in thin) was “acquired by 6;0-6;11 (ordered by mean age of acquisition, 90% criterion).”
4. Thompson B (CCC-SLP). Lisping: Understanding the 4 Types, Causes and How SLPs Correct Them. SpeechPathology.org. Updated August 13, 2026. Checked October 11, 2026.
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   “Speech-language pathologists classify lisps into four types: frontal (interdental), lateral, palatal, and dentalized.” “Correct /s/ production requires the tongue tip to rest just behind the upper front teeth while air flows down a narrow groove along the tongue’s center. Each lisp type represents a specific breakdown in that precise positioning or airflow pattern.”
5. Communication Health Support Association. Speech Sound Disorders. Consumer guide. Checked October 11, 2026.
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   “Most children can say almost all speech sounds correctly by 4 years old.” “By 3 years: Says m, n, h, w, p, b, t, d, k, g, and f in words.” “It’s normal for young children to make occasional speech mistakes as they’re learning to talk, but it could be a problem if they keep making those mistake as they get older.” “Hearing should be checked to rule out hearing loss, which can affect speech development.”
6. American Speech-Language-Hearing Association. Orofacial Myofunctional Disorders. Practice Portal. Checked October 11, 2026.
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   “OMDs are movement patterns that involve oral and orofacial musculature, which result in incorrect positioning of the tongue at rest and during swallowing, breathing, and speech production.” “Estimates of tongue thrust swallow in school-aged children range from 5.4% (Kasparaviciene et al., 2014) to 62.3% (Sasigornwong et al., 2016). Children with speech sound disorders are more likely to exhibit a tongue thrust swallow (Wadsworth et al., 1998).” “In one study, approximately 31% of children diagnosed with chronic mouth breathing exhibit a speech sound disorder (Hitos et al., 2013).” “Research on the impact of ankyloglossia, or tongue-tie, on newborn feeding and later speech development is conflicting but trends toward outcomes showing minimal to no impact on speech and feeding”; “Dydyk et al. (2023) identified a statistically significant association between the severity of ankyloglossia and the presence of speech sound disorders”. “Dental malocclusions demonstrate significant correlations with different signs of OMDs (i.e., tongue thrust swallow, oral habits) and speech sound disorders”. Signs include “Distorted productions of /s, z/, often with an interdental lisp”. Causes include “Chronic nonnutritive sucking and chewing habits past 3 years of age” and “premature exfoliation of the maxillary incisors”. “an orthodontist may need to treat a child’s open bite before the clinician provides interventions for a tongue thrust and/or an interdental lisp.”
7. Assaf DDC, Knorst JK, Busanello-Stella AR, Ferrazzo VA, Berwig LC, Ardenghi TM, Marquezan M. Association between malocclusion, tongue position and speech distortion in mixed-dentition schoolchildren: an epidemiological study. Journal of Applied Oral Science. 2021;29:e20201005. PMID 34406316. Checked October 11, 2026.
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   “A total of 547 children were evaluated. Schoolchildren who presented anterior open bite (PR 2.36 95%CI 1.59-3.49) and having oral/oral-nasal breathing (RP 2.51 95%CI 1.70-3.71) are more likely to have altered position of the tongue.” “deep overbite presents a protective relationship to speech distortion (PR 0.41; 95%CI 0.24-0.71), whereas schoolchildren with posterior crossbite were more likely to present this problem (PR 1.77; 95%CI 1.09-2.88).” Introduction: “Between the main types of speech alterations, distortion (anterior and lateral lisp) is due to musculoskeletal, and for this reason, it is one of the interest in this study.”
8. Barbosa C, Vasquez S, Parada MA, Gonzalez JC, Jackson C, Yanez ND, Gelaye B, Fitzpatrick AL. The relationship of bottle feeding and other sucking behaviors with speech disorder in Patagonian preschoolers. BMC Pediatrics. 2009;9:66. PMID 19845936. Checked October 11, 2026.
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   “A total of 128 three- to five-year olds were assessed”; “A three-fold increase in relative odds of speech disorder was found for finger-sucking behavior (OR: 2.99, 95% CI: 1.10-8.00) and for use of a pacifier for 3 or more years (OR: 3.42, 95% CI: 1.08-10.81).” Limitations: “due to the observational nature of the study design, confounding factors could adversely impact our findings. Second, the parent’s survey data were collected by self-reports and there is the possibility of measurement error and recall biases.” Background: sucking habits “had effects on developing dentition, most notably on upper labial segment alignment and the development of anterior open bites and posterior cross bites”.
9. American Speech-Language-Hearing Association. Speech Sound Disorders: Articulation and Phonology. Practice Portal. Checked October 11, 2026.
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   Distortions: “Sounds are altered or changed (e.g., a lateral /s/).” Risk factors: “Biological sex”, “Pre- and perinatal problems”, “Family history”, “Persistent otitis media with effusion”. “In young adults, 1%-2% exhibit residual or persistent speech errors (Flipsen, 2015).” The oral mechanism examination includes “dental occlusion and specific tooth deviations; the structure of hard and soft palate (clefts, fistulas, bifid uvula); and the function (range of motion) of the lips, jaw, tongue, and velum.” “A hearing screening is conducted during the comprehensive speech sound assessment, if one was not completed during the screening.” Stimulability testing helps determine “whether the sound is likely to be acquired without intervention”. Treatment: “establishment”, “generalization”, “maintenance”; techniques include “Using a mirror for visual feedback”, “Using ultrasound imaging”, “Using palatography”. “SLPs carefully consider what a particular oral motor activity is likely to accomplish and whether it addresses the child’s speech sound error”. Persisting difficulties carry a risk of “psychosocial problems (e.g., low self-esteem, increased risk of bullying”).
10. Flipsen P, Sacks S, Neils-Strunjas J. Effectiveness of systematic articulation training program accessing computers (SATPAC) approach to remediate dentalized and interdental /s, z/: a preliminary study. Perceptual and Motor Skills. 2013;117(2):559-577. PMID 24611257. Checked October 11, 2026.
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    “Participants were 18 children aged 6 years, 9 months to 11 years, 10 months. Treatment involved once per week, individual, 10-min. sessions with an experienced speech-language pathologist. Group A (n = 9) received 15 weeks of treatment, while treatment was delayed for Group B (n = 9).” “During period one, Group A (treated) significantly improved their accuracy of /s, z/ in spontaneous speech, while Group B (untreated) showed no significant change. During period two, Group B improved significantly when treatment was applied. The majority of the participants retained proficiency two years later.”
11. Lee AS, Gibbon FE. Non-speech oral motor treatment for children with developmental speech sound disorders. Cochrane Database of Systematic Reviews. 2015;(3):CD009383. PMID 25805060. Checked October 11, 2026.
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    “NSOMTs are non-speech activities that aim to stimulate or improve speech production and treat specific speech errors. For example, using exercises such as smiling, pursing, blowing into horns, blowing bubbles, and lip massage”; “three studies (from four reports) involving a total of 22 children”; “Two studies did not find NSOMT as adjunctive treatment to be more effective than conventional speech intervention alone”; “One study reported a change in postintervention articulation test results but used an inappropriate statistical test”; “Currently no strong evidence suggests that NSOMTs are an effective treatment or an effective adjunctive treatment for children with developmental speech sound disorders.”
12. McLeod S, Crowe K. Children’s Consonant Acquisition in 27 Languages: A Cross-Linguistic Review. American Journal of Speech-Language Pathology. 2018;27(4):1546-1571. PMID 30177993. Checked October 11, 2026.
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    “A cross-linguistic review was undertaken of 60 articles describing 64 studies of consonant acquisition by 26,007 children from 31 countries in 27 languages”; “most of the world’s consonants were acquired by 5;0 years;months old.” “Plosives, nasals, and nonpulmonic consonants (e.g., clicks) were acquired earlier than trills, flaps, fricatives, and affricates. Most labial, pharyngeal, and posterior lingual consonants were acquired earlier than consonants with anterior tongue placement.”
13. Flipsen P. Emergence and Prevalence of Persistent and Residual Speech Errors. Seminars in Speech and Language. 2015;36(4):217-223. PMID 26458197. Checked October 11, 2026.
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    “Findings from several different sources suggest that 1 to 2% of the young adult population overall may present with these errors. Up to 75% of these errors may resolve on their own between the end of the developmental period (i.e., age 9 years) and the end of high school, though speech therapy services may still be justified to reduce any negative social consequences of these errors.”
14. Strutt C, Khattab G, Willoughby J. Does the duration and frequency of dummy (pacifier) use affect the development of speech? International Journal of Language and Communication Disorders. 2021;56(3):512-527. PMID 33939239. Checked October 11, 2026.
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    “A total of 100 British-English children aged 24-61 months”; “the majority of speech outcomes are not significantly associated with dummy use, however measured”; “there is a significant association between increased atypical errors and greater frequency of daytime dummy use”, “not observable within children older than 38 months”. “The evidence base for any effects of dummy use on speech is very small.”
15. Messner AH, Lalakea ML. The effect of ankyloglossia on speech in children. Otolaryngology: Head and Neck Surgery. 2002;127(6):539-545. PMID 12501105. Checked October 11, 2026.
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    “We conducted a prospective study of 30 children aged 1 to 12 years with ankyloglossia undergoing frenuloplasty.” “Preoperative speech pathology evaluation documented articulation problems thought due to ankyloglossia in 15 of 21 children. Postoperative evaluation in 15 of these children showed improvement in articulation in 9, no change in 4 who had normal speech preoperatively, and an ongoing articulation disorder in 2.”
16. Adewumi AO, Horton C, Guelmann M, Dixon-Wood V, McGorray SP. Parental perception vs. professional assessment of speech changes following premature loss of maxillary primary incisors. Pediatric Dentistry. 2012;34(4):295-299. PMID 23014086. Checked October 11, 2026.
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    “Healthy 5- to 6-year-olds ... who received PEMPI between the ages of 2 and 4 years old”; “57 parental interviews were completed. Sixty percent (34) felt their children sounded different following extractions, and 65% (37) reported difficulty with pronunciation of the ‘s’ sound. For children who were perceived by their parents to sound different, 46% had problems pronouncing words with the letters s and z. For parents who did not perceive speech changes, none of the children had problems with s and z as determined by the professionally conduced speech evaluations”.
17. Gable TO, Kummer AW, Lee L, Creaghead NA, Moore LJ. Premature loss of the maxillary primary incisors: effect on speech production. ASDC Journal of Dentistry for Children. 1995;62(3):173-179. PMID 7560362. Checked October 11, 2026.
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    “The articulation of twenty-six subjects who had their teeth extracted before the age of five years was evaluated at eight, nine, or ten years old and compared with the articulation of an age-matched comparison group with normal exfoliation of their incisors. T-tests for related measures revealed no statistically significant differences”.
18. Hurley CR, McLeod S, Anthonappa RP. Extraction of primary maxillary incisors and children’s speech production: A case series. Clinical Linguistics and Phonetics. 2025;39(4-5):427-439. PMID 38797933. Checked October 11, 2026.
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    “This case series describes a prospective study reporting the impact of primary maxillary incisor teeth extraction on speech sound accuracy for three children”; “Speech sound difficulties were present before dental treatment in all participants and extraction of primary maxillary incisors did not significantly impact speech production.”
19. Cleveland Clinic. Articulation Disorder: What It Is, Symptoms and Treatment. Health Library, medically reviewed. Last updated May 13, 2026. Checked October 11, 2026.
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    “Chronic ear infections: Children with frequent middle ear infections are more likely to have articulation disorder.” “Hearing loss: Children learn to talk by listening to others and imitating them, which is why hearing loss may lead to speech issues.” “Dysarthria: This is a motor speech disorder that can happen if something damages your child’s nervous system. Examples are cerebral palsy, stroke or traumatic brain injury.” “They may feel self-conscious about speaking. They may avoid reading aloud, talking to others or saying certain words.” “By age 4, you should understand most of your child’s speech.”
20. Sugden E, Lloyd S, Lam J, Cleland J. Systematic review of ultrasound visual biofeedback in intervention for speech sound disorders. International Journal of Language and Communication Disorders. 2019;54(5):705-728. PMID 31179581. Checked October 11, 2026.
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    “Twenty-eight papers, comprising 29 studies, met the inclusion criteria”; “80.6% of participants across all reviewed studies receiving intervention targeting rhotics”; “Current evidence indicates that U-VBF may be an effective adjunct to intervention for some individuals whose speech errors persist despite previous intervention.”
21. Yiu OY, Wong WHS, Pokta F, Fong AYT, Tso WWY, Ip P. The Effectiveness of Ultrasound Visual Biofeedback in Articulation Therapy for Children and Adolescents With Speech Sound Disorders: A Systematic Review and Meta-Analysis. International Journal of Language and Communication Disorders. 2026;61(2):e70209. PMID 41705595. Checked October 11, 2026.
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    “35 studies (192 unique participants, aged 4-18) were included (16 for meta-analysis). The pooled d2 was 1.32 (95% CI [0.54, 2.10]), indicating substantial improvements in accuracy despite high heterogeneity”; “Funnel asymmetry (z = 2.478, p = 0.013) suggested potential publication bias.”
22. Alder Hey Children’s NHS Foundation Trust, Community Speech and Language Therapy Department. Producing /s/: ‘lisp’ advice. Patient information leaflet. Last reviewed April 1, 2025. Checked October 11, 2026.
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    “A lisp sound quality is created when ‘s’ is being produced with the tongue between the teeth (interdental lisp). Help your child to hear the difference between ‘s’ and the sound they produce. Encourage your child to tuck their tongue behind their teeth when saying the ‘s’ sound. Show them using a mirror”; “Once they are producing ‘s’ consistently while reading try to have 5-minute chats where you focus on remembering clear ‘s’ during your conversations”.
23. Badan Pengembangan dan Pembinaan Bahasa. cadel. Kamus Besar Bahasa Indonesia (KBBI VI Daring). “kurang sempurna mengucapkan kata-kata sehingga bunyi [r] dilafalkan [l], (misalnya kata raja diucapkan laja); pelat; telor”, that is, saying words imperfectly so that the r sound is pronounced as l. Checked October 11, 2026.

Medical disclaimer. This page is for general educational purposes and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified professional about your own child.