Three-dimensional force measurements applied by infant during nipple sucking^.

The objective of this study was to elucidate the dynamic mechanism of infant tongue movement during sucking. We developed an integrated device with sensors for three-dimensional force measurements applied by the tongue to an artificial nipple. Three mini-size built-in cantilever sensors were installed in each of three sides of the regular hexagonal prism (nine sensors in total) inside the artificial nipple. Signals from the force sensors were amplified and displayed on a PC monitor via USB in real time. We conducted measurements using the system and confirmed that signals were outputted from all nine sensors. The output waveforms and force distributions showed that the force applied was larger at the nipple tip than at the nipple root and moved from the nipple root to the nipple tip.