Lisping in children – why does your child lisp and when should you see a speech therapist?

Many adults find lisping in pre-schoolers endearing, treating it as a natural stage of speech development that will “pass on its own.” Articulation does keep developing until around the sixth year of life, yet some forms of lisping – especially those where the child pushes the tongue between the teeth – never disappear without a therapist's intervention.

What exactly is lisping (sigmatism)?

Lisping, medically called sigmatism, is the incorrect pronunciation of the so-called dental sounds. This mainly concerns three groups of sounds that appear in a child's development at different times:

• the sibilant group (s, z, c, dz),
• the hushing group (sz, ż, cz, dż),
• the hissing group (ś, ź, ć, dź).

If a five-year-old says “safa” instead of “szafa” (wardrobe), this is often simply a delay in natural development (so-called physiological lisping), because the hushing sounds appear latest. If, however, the child pushes their tongue between their teeth while saying “słońce” (sun) – this is a speech disorder (interdental lisping) that requires work straight away, regardless of the child's age.

The most common causes of lisping in children

A speech disorder almost never appears “out of nowhere.” It is a symptom of an abnormality in the anatomy or functioning of the speech organs. The most common causes of sigmatism include:

Mouth breathing. A constantly open mouth lowers the muscle tone of the lips and cheeks. The tongue rests on the floor of the mouth and becomes floppy, which is a direct route to it slipping between the teeth during speech. We write about when an open mouth needs a wider consultation in our article on a child breathing through the mouth.

A shortened lingual frenulum (ankyloglossia). If the tissue under the tongue is too short, the tongue has no physical way of lifting to the palate to correctly pronounce sounds such as “sz.”

Prolonged dummy or thumb sucking. These habits entrench an infantile swallowing pattern and distort the palate and the bite.

Malocclusion. An open bite (a gap between the teeth) creates an ideal space for the tongue to slip into.

When should you take your child to a speech therapist?

A quick diagnosis can spare a child difficulties at school – remember that children with speech disorders also frequently struggle with learning to read and write (risk of dyslexia). If you notice signs of delayed speech development in your child, it is worth consulting a specialist as early as possible.

A visit to a children's speech therapist is strongly recommended if:

• the child (even a two-year-old!) pushes the tongue between the teeth or lips while speaking or at rest,
• after age 3 the child's speech is completely unintelligible to those around them,
• facial asymmetry is visible while speaking (so-called lateral lisping, which distorts the airflow),
• at 5–6 years old the child still does not pronounce the hushing sounds (sz, ż, cz, dż).

It is worth remembering that lisping is often not only an articulation problem but also an orofacial function problem. That is why at StacjaMowa we often combine speech therapy with myofunctional therapy, to strengthen at the same time the muscles responsible for correct tongue position, breathing, and swallowing.

Proven speech therapy exercises for home practice

Speech therapy is teamwork – with the speech therapist in the clinic and the parent at home. Below are exercises that prepare the articulation apparatus (so-called mouth and tongue gymnastics), which are worth weaving into everyday routines:

1. “Horse” (tongue clicking): a great exercise that lifts the tongue, helping to strengthen the muscles used for pronouncing the hushing sounds and “r.”
2. “Painting the ceiling”: the child opens their mouth wide and moves the tip of the tongue from the teeth towards the back of the palate (“painting the ceiling”).
3. “Licking jam”: spread jam or chocolate spread on the child's upper lip, and their task is to lick it off with the tip of the tongue while keeping the mouth open. This strengthens tongue elevation.
4. Drinking through a curly straw: strongly engages the orbicular lip muscle, helping the lips close correctly.

If your child has been started on ENMOT electrostimulation, make sure to strictly follow the recommendations the therapist adds to the home exercises.

Sources and literature

• Jastrzębowska G., Pelc-Pękala O., “Logopedia. Pytania i odpowiedzi” [Speech Therapy. Questions and Answers], Wydawnictwo UO.
• Skorek E.M., “Oblicza wad wymowy” [The Faces of Speech Disorders], Wydawnictwo Akademickie Żak.
• Position of the Polish Speech Therapy Association (PTL) on speech therapy prevention at pre-school age.

We describe the scope of speech therapy support on our speech therapy in Gdańsk page.