Dentofacial morphology and tongue function during swallowing.

To understand the role of the tongue in the development of occlusion, we examined the relationship between tongue movements during swallowing and dentofacial morphology with ultrasonography, cephalometric radiography, and dental casts. Duration, magnitude, and speed of tongue movements were measured in 112 healthy adult volunteers and compared with their dentofacial morphology with a simple correlation analysis. The results showed that the movements of tongue during swallowing are related to dentofacial morphology, especially in the motion magnitude of the early final phase (phase IIIa), but that few correlations are found when analyzing the duration and the speed of swallowing.