|Budget Amount *help
¥3,400,000 (Direct Cost : ¥3,400,000)
Fiscal Year 2000 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1999 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1998 : ¥2,400,000 (Direct Cost : ¥2,400,000)
Four magnetic sensors were attached on lower incisor part, a head, and a right and left shoulder. The sensor for tongue shape was constructed five bimorph piezoelectric films which were arranged to the series, and those sensor was bonded to the surface of tongue. The voltage generated by the tongue shape change was obtained with this sensor at spontaneous swallowing. These methods were enabled to obtain the postural information of the head, mandible and the upper body, and the shape information of the tongue in three-dimensional space.
The subjects who had participated in this study were explained the content of the experiment beforehand, and consented to the cooperation of this study. These subjects were composed of the normal occlusion case and the openbite case. The measurements of the postural changes for the head, mandible and the upper body were at a rest position and a voluntary swallowing. In addition, the measurements of the tongue shape were achieved at spontaneous deglutition
1) The mandibular tracking of subjects was in observed by using three dimensional computer graphics in real time.
2) The head posture of an openbite case had a tendency that the head inclined to up for the postural change to a normal occlusion case at the rest. The upper body of an openbite case did not show the characteristic tendency. In spontaneous swallowing, the head posture of a normal occlusion case showed the postural change synchronizing with the movement of mandibular posture, and a tendency similar as for the upper body was recognized, but the postural change was a little. In an openbite case, the synchronization of the postural change of mandible and the postural change of the head and upper body was not clear.
3) 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. 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. Less