Question: Would the use of lip retractors, or pulling down the bottom lip, or any other similar manipulation of the lips/face in order to get a good view of a potential tongue thrust during swallowing actually “ignite” a thrust? (influence one to occur that otherwise might not? give a false positive per se…..) J
Response by Dr. Robert Mason: Good question. The answer: Heavens yes!! When you artificially hold open the lips, the need for an anterior seal for a swallow is then passed on to the remaining structure capable of achieving an anterior seal – the tongue. What you then see is an artificially-induced tongue thrust as the tongue provides the anterior seal. When one holds the lower lip down or uses lip retractors, the subject, in such artificially contrived circumstances, is encouraged to concentrate on their swallow, and a tongue forward initial movement is the typical result. Of historical importance: the reason that palatography (the best example of which is the old Payne light used and touted by Garliner) was not a valid evaluation technique is because it involved painting the palatal area. The subject then had to start a swallow sequence from an unnatural rest (open mouth) position; hence, the swallow was distorted due to the need to not touch the palate with the tongue prior to a swallow.
Additional comments by Sandra R. Holtzman: That is why I stopped using the Payne black light method quite a few years ago. Are you looking for a way to break the lip seal during a saliva swallow? Truthfully, you can see what you need by having them chew and swallow something of a texture like a pop tart and break the lip seal during the swallow. How they swallow food and saliva will be the same, but it will be easier to see with the food swallow. Remember, that the actual swallow is not as significant as we used to think; therefore, even if you failed to get that part of an eval done, you still have all the symptoms to work with in order to correct the orofacial myology disorder. You can demo that symptom at a later session, if you wish. You probably already know, but to break the lip seal: “Lightly” place one hand on larynx as patient bites, chews, and suctions; as she/he swallows and the larynx elevates, take that moment to break the lip seal and see if the tongue is coming between the teeth. You would place your thumbs at the commissures and lift one thumb upward and the other downward on the lips, and might even hear the seal “break” (pop). Bear in mind that this method is good for those in the past who did not have the more involved eval procedures that we have and use today. It was good to “show” parents or patients how the tongue came between the teeth during the swallow and was only useful for the few who had obvious interdental swallows. Other than for convincing them/selling them on the need for treatment, I don’t see why it is important at all to use that demonstration. With all the wonderful tools and methods available to us, there is a lot more to emphasize and demonstrate during the evaluation process, in my opinion…..