No abstract

Previous ultrasonographic studies on tongue functions were limited by the possibility of artifacts caused by movement of the submental area during function. Consequently, tongue movements were misinterpreted. A dynamic tongue imaging technique, the cushion‐scanning technique, was used to overcome this problem. Later, swallowing was investigated and divided into five phases using cushion‐scanning technique‐aided M‐mode ultrasonograms. In this study, cushion‐scanning technique in combination with the B‐mode and M‐mode ultrasonography was applied to investigate and measure the tongue movement during swallowing in 55 normal persons. The average duration, range of motion and speed of swallowing were found to be 2.43 s, 24.06 mm, and 10.34 mm/s, respectively. The computer‐aided B‐mode plus M‐mode ultrasonography in combination with the cushion‐scanning technique is a valuable tool for study of tongue functions.

In order to investigate the difference in tongue movement between visceral (infantile) and somatic (mature) swallowing patterns, 12 visceral (seven females, five males) and 14 somatic (eight females, six males) swallowers were examined with the B+M-mode ultrasound technique. Movements of the tongue tip and submental musculature during swallowing were recorded on video cassette and evaluated with a personal computer. The results demonstrated that the tongue dorsal surface, which was thought to be ideal for observing tongue function, was not suitable for differentiating between visceral and somatic swallowing patterns. Conversely, the movements of the genioglossus muscle were found to be identical within groups but significantly different (P < 0.01) from each other between the two swallowing patterns. Therefore, the genioglossus muscle can serve as a reliable means for differentiating between visceral and somatic swallowers.

When occurring separately, awake and sleep bruxism are significant risk factors for TMD pain. In case of simultaneous presence, the risk for TMD pain is even higher.