University Clinic Erlangen, Germany.
Int J Oral Maxillofac Implants. 2012 Jan-Feb;27(1):29-35.
Although several investigations of the fit of computer-aided design/computer-assisted manufactured implant restorations have been reported in the literature, very limited information is available on the accuracy of dental scanners for surface data acquisition. The objective of this research project was to investigate the accuracy and repeatability of a three-dimensional noncontact laser scanning system based on conoscopic holography recording the spatial orientation of an implant in vitro.
One master cast containing five nonparallel implant replicas with scan abutments (implant position locator [IPL], Nobel Biocare) was repeatedly digitized by two commercially available dental scanners and an industrial highprecision coordinate measuring machine as a reference. Repeated measurements of the center point and vector analysis were applied to determine the accuracy and repeatability of IPL orientation. The Wilcoxon signed rank test modified for equivalence was applied to determine whether the systems were equally accurate based on given threshold limits of 0.010, 0.005, and 0.001 mm.
All between-system tests identified significant differences, although most differences were very small in absolute terms. Tests for equivalence based on difference windows were exploratorily significant for 0.010 and 0.005 mm.
Conoscopic holography scan technology is a valid option to supplement dental touch-probe scanners for laboratory digitization of implant master casts.
尽管文献中已经报道了许多关于计算机辅助设计/计算机辅助制造植入物修复体拟合的研究，但关于用于表面数据采集的牙科扫描仪的准确性的信息非常有限。本研究项目的目的是研究基于相衬全息记录空间取向的三维非接触激光扫描系统在体外植入物的准确性和可重复性。
一个包含五个非平行植入物复制品和扫描接杆（植入物位置定位器[IPL]，Nobel Biocare）的主模型被两个商业上可用的牙科扫描仪和一个工业高精度坐标测量机重复数字化作为参考。中心点的重复测量和向量分析被应用于确定 IPL 方向的准确性和可重复性。基于给定的 0.010、0.005 和 0.001 毫米的阈值限制，应用了等效性修正的 Wilcoxon 符号秩检验来确定系统是否具有相同的准确性。
所有的系统间测试都确定了显著的差异，尽管大多数差异在绝对值上非常小。基于差异窗口的等效性测试对于 0.010 和 0.005 毫米是探索性显著的。
相衬全息扫描技术是一种有效的选择，可以补充牙科触针扫描仪，用于植入物主模型的实验室数字化。
