I receive weekly questions about the severe frontal lisp. The questions always are about how to keep the tongue inside the mouth for speech. We are talking here about the client who has: 

• Interdental tongue placement on all the sibilants: S, Z, Sh, Zh, Ch, J
• Interdental tongue placement on all the lingua-alveolar sounds: T, D, N, L
• Open mouth resting posture
• Reverse swallow (infantile suckle-swallow, tongue-thrust swallow)

From a motor perspective, the severe frontal lisp with interdental tongue placement during speech is a problem of oral stability. The problem is not just in the tongue: The problem is in the whole face. Oral stability is the combination of jaw stability, tongue stability, and cheek/lip stability working together to stabilize the face in the appropriate position for speech (and feeding, too). Stability is always proximal, or near the trunk of the body. Thus oral stability is maintained in the posterior of the oral cavity. This entire problem revolves around a loss of proximal stability in the oral mechanism.

All movements consist of an interplay of mobility and stability. SLP’s in general usually are over-focused on oral mobility, and they seem to know very little about stability. But appropriate stability is what allows for advanced and accurate mobility. A client like the one described above has poor oral mobility because he has not developed correct oral stability. He is speaking without oral stability. Therapy should be directed toward establishing oral stability first, and then toward stimulating oral mobility.

Jaw

The mouth is open, and the tongue is forward, because the jaw is allowed to hang low. The client needs to learn to maintain a higher jaw position for speech. This is the stable position of the jaw. I use straws. I place a straw lengthwise along the side teeth, between the molars on one side, and I have the client bite into it. A straw will be flexible, so the client can learn to adjust the jaw slightly upward and downward. I find that bite sticks are good only at a gross level of jaw stability because they are stiff. A flexible straw allows the client to experiment with slight jaw elevation and depression while working on speech sounds. Have the client watch himself in a mirror to understand the concept of the jaw moving slightly higher. Practice T, D, N, and L with the jaw held high with the straw. Then move on to the sibilants. Teach the client to see and hear the difference in his sounds with the jaw slightly higher and slightly lower. Teach him that the high jaw position looks and sounds best.

Tongue

The client also needs to learn how to stabilize the tongue with its back-lateral margins. I call these the “shoulders” of the tongue. They also have been called the “anchors” and “fulcrums” of the tongue, as well as other names. I teach my clients to produce “Long E” (as in the word “Bee”). The E position is basically the same as the position of back-lateral tongue stability. If you feel yourself produce an E, you will feel that the back-lateral margins of the tongue articulate with the palate and molars on each side. This is where the tongue anchors itself for mobility in mature speech. I teach my clients to over-practice a very exaggerated E as a way to establish back-lateral tongue stability.

Cheeks/Lips

The cheeks also need to learn to maintain slight retraction so that the face and lips are not hanging forward. Over-practicing an exaggerated E also will aid in this regard. This must be a big exaggerated E to expose all the teeth and to pull the lips into retraction.

A Big Exaggerated E

The easiest easy way to address all these issues is to have your clients over-practice words with a big, over-exaggerated Long E. This E is practiced with a big wide smile, and with the teeth clenched in the back. This pulls the jaw up, the tongue in, and the cheeks and lips back. I use the following:

• Exclamations – Eee! Eeek! Weee!
• CV Words –Bee, Dee, Fee, Gee, He, Key, Lee, Me, Pee, See, Tee, Tea
• Diminutives – Mommy, Daddy, Baby, Kittie, Doggie, Horsie, Owie, Ickie…
• Alphabet Letters – B, C, D, G, P, T, V, Z
• Initial E Words – Eat, Easy, Each, Edyth, Eel…

Once clients are producing these E words well, and if they have the cognitive skills for it, I then teach them to go into E position, to hold it, and then to say the other sounds that are interdental. If the client can hold E, he will not be able to protrude the tongue. Over time, relax the E position.

The concept of oral stability appears hither and yon throughout the history of articulation therapy. I will be discussing it thoroughly in a book called 21st Century Articulation Therapy to be published in 2012-2013.