Why tongue looks smaller with treatment

Question to Dr. Robert Mason: In your text you say, “once muscles have been trained through treatment, a tongue that seemed definitely large has assumed a much more normal appearance”.  Can you explain this please.

Answer: Yes, but you already know the answer. You will recall how the hyoid bone drops down and the tongue can accommodate to changes in the horizontal or vertical dimensions of the oral cavity by adapting vertically. This is more logical than adapting by moving horizontally (back) and reducing the size of the airway. This dropping down maneuver of the tongue was identified in the article by Wickwire, White and Proffit, J. Oral Surgery, 1978. That study was of patients who had a surgical setback of the mandible. Afterward, the previously large tongues appeared smaller as they adapted to the space available. The adaptation is usually seen in the vertical dimension, with the base of the tongue dropping down. The hyoid is a good marker, as it also is in collapsibility studies of sleep apnea patients. I will attach that article relating hyoid position to sleep apnea studies. By contrast, what some in dentistry have claimed about the tongue falling back (horizontally) and blocking the pharynx following orthodontic extractions, and then leading to sleep apnea problems, is not a valid statement that has any research support.