Kimura H, Sohmura T, Watanabe T
Shika Zairyo Kikai. 1989 Jul;8(4):551-8.
In order to improve the accuracy of the three dimensional shape measurement, the divisional measurement method, which tilts and rotates the abutment teeth was attempted. This system is composed of a high precision laser displacement meter, teeth model scanning machine and personal computer. For the measurement of a crown abutment tooth with indistinct margin lines, the measuring area was divided into four regions of the mesio-distal sides and the buccal-lingual sides. The tooth was tilted on the gonio stage +/- 30 degrees around the mesio and distal direction, rotated 180 degrees around the tooth axis, and measured divisionally. The partial data thus obtained were combined by means of the software program into the composed data. Using this method of measurement, the margin of the abutment tooth was recognizable, and the faulted data, which arose from shielding of the receiving beam, was eliminated. Overlapping data from divisional measurements were deducted and the complete data for the single abutment tooth was saved into a file. In the case of a MOD inlay abutment tooth, the divisional measurements with only rotation were carried out, since each curved wall makes nearly a square angle and sharp boundary. A couple of data sets were combined and complete data without error was obtained. Thus, measurements of abutment teeth were obtained without error. It is possible to get the basic data for the production of crown and inlay by means of CAM technique.
为了提高三维形状测量的精度，尝试了对基牙进行倾斜和旋转的分区测量方法。该系统由高精度激光位移计、牙齿模型扫描仪和个人计算机组成。对于边缘线不清晰的冠基牙测量，将测量区域划分为近远中侧和颊舌侧四个区域。牙齿在测角台上围绕近中及远中方向倾斜±30度，围绕牙轴旋转180度，并进行分区测量。由此获得的部分数据通过软件程序组合成合成数据。使用这种测量方法，基牙的边缘清晰可辨，消除了因接收光束遮挡而产生的错误数据。扣除分区测量的重叠数据，将单个基牙的完整数据保存到文件中。对于MOD嵌体基牙，由于每个弯曲壁几乎成直角且边界清晰，仅进行旋转分区测量。将几组数据集合并，获得无误差的完整数据。因此，基牙测量无误差。通过计算机辅助制造（CAM）技术可以获得制作牙冠和嵌体的基础数据。
