生体計測用に改良した3次元6自由度・支台歯挙動解析装置

抄録

Abutment tooth movement was analyzed in vivo by improving the six-degree of freedom tooth movement tracking device which had been developed by Imamura.
The results obtained were as follows:
I. On the measurement device
1) The laser oscillator unit became to be lighter at only 15gr including the crown-holder attached to the abutment tooth through replacing the beam spliter to a half-prism.
2) Making the three PSDs smaller and shortening the distance of each PSD enabled to measure the abutment tooth movement under room lights of a dental office.
3) Three percent of magnifying figures were obtained at the point of 2 mm from the middle point of PSD on the x-axis and the y-axis respectively. Through improving each PSD to be able to easily slide up and down and rotate, acuurate data can be obtained anytime without any distortion.
II. On results measured by utilizing the device.
1) Even after complete occlusal equilibration, large inclination was recognized on the abutment tooth at swallowing strongly. Especially inclination of Kt which is considered to be a rigid support type was significantly larger than that of Ak (p<0.001), and the abutment tooth with Kt tipped distally than that with Ak.
2) No significant difference was recognized between Kt-short and Ak-short, and between Ak-short and Ak-long, but on inclination between the abutment tooth with the Kt group and the Ak group when functioning, the former was larger than that of the latter at the risk level of five percent.
3) Significant difference of 99.9 percent level was recognized on rotation of the abutment tooth between Kt-none and Ak-none, Kt-short and Ak-short, and the former was larger than that of the latter respectively.
Improved measurerment device became to be used effectively and efficiently as analysing the abutment movement in vivo.
No positive evidence of superiority of the Kt of rigid support was secured, although the subjects were too few in this test.