Analysis of abnormal tongue movement by three dimensional tongue movement measurement device with bimorph piezopolymer thin film

本研究的受试者包括正常牙合1例和开牙合1例，均已获得合作研究的同意。传感器在舌矢状面方向上按三排排列，共排列五片压电双晶片薄膜。舌中央部外侧的弯曲度明显小于舌背的弯曲度。其弯曲特征也与中部的弯曲特征相似。结果表明：（1）正常咬合时，舌背传感器的弯曲度较大，舌背向上弯曲;（2）正常咬合时，舌背传感器的弯曲度较大，舌背向上弯曲;开牙合患者舌背曲度较小，吞咽时舌背趋于平滑; 2.正常牙合患者舌背向下运动在舌尖到达最高位之前就已开始，舌尖到达最高位后舌背最向下。在开牙合病例中，背侧向下的起始时间与正常牙合病例相似。但舌尖运动量较小，舌背下降较正常早，舌尖位于舌背最下方之前舌背已位于舌背最上方。据推测，已经适应于前开牙合的补偿性舌运动发生以维持用于吞咽的负气压。由于受试者较少，在今后的研究中应增加受试者。

The subjects of this research was composed of normal occlusion 1 case and openbite 1 case which had obtained the agreement of cooperation for this research. The sensor which arranged five bimorph piezopolymer thin films was arranged by three rows in the direction of tongue's sagittal plane. However, the curvature on the lateral side was considerably smaller than the curvature in dorsum of tongue central part. The characteristic of the curvature was also similar to the curvature in central part. It was enough in the measurement only of tongue central part in tongue movement at swallowing in the above-mentioned reason.The results were at follows.1.In normal occlusion case, the curvature of the sensor in the dorsum of tongue was large, and upward in the dorsum of tongue was admitted. However, in openbite case, the curvature in the dorsum of tongue was small and the dorsum of tongue was a smooth tendency while swallowing.2.In normal occlusion case, the downward in the dorsum of tongue had started before the tongue tip reached an uppermost position, and after the tongue tip reached an uppermost position, the dorsum of tongue was located most downward. In openbite case, the beginning time of the dorsum's downward was similar to the normal occlusion case. However, amount of the movement on the tongue tip was small, the descent of the dorsum of tongue appeared at the early stage compared to the normal occlusion case, and dorsum of tongue had been located most downward before the tip of tongue was located in uppermost one.From the above-mentioned result, it was guessed that the compensatory tongue movement which had been adapted to anterior openbite occurred to maintain a negative air pressure for swallowing. Because the subjects were few, subjects should be increased in the next research.