Justus-Liebig-University, Dental Clinic, Department of Prosthodontics, Giessen, Germany.
Justus-Liebig-University, Dental Clinic, Department of Prosthodontics, Giessen, Germany.
J Prosthodont Res. 2018 Apr;62(2):245-251. doi: 10.1016/j.jpor.2017.10.004. Epub 2017 Nov 27.
An accurate impression is required for implant treatment. The aim of this in-vitro study was to determine the effect size of the impression material/method, implant system and implant angulation on impression transfer precision.
An upper jaw model with three BEGO and three Straumann implants (angulations 0°, 15°, 20°) in the left and right maxilla was used as a reference model. One polyether (Impregum Penta) and two polyvinyl siloxanes (Flexitime Monophase/Aquasil Ultra Monophase) were examined with two impression techniques (open and closed tray). A total of 60 impressions were made. A coordinate measurement machine was used to measure the target variables for 3D-shift, implant axis inclination and implant axis rotation. All the data were subjected to a four-way ANOVA. The effect size (partial eta-squared [η]) was reported.
The impression material had a significant influence on the 3D shift and the implant axis inclination deviation (p-values=.000), and both factors had very large effect sizes (3D-shift [η]=.599; implant axis inclination [η]=.298). Impressions made with polyvinyl siloxane exhibited the highest transfer precision. When the angulation of the implants was larger, more deviations occurred for the implant axis rotational deviation. The implant systems and impression methods showed partially significant variations (p-values=.001-.639) but only very small effect sizes (η=.001-.031).
The impression material had the greatest effect size on accuracy in terms of the 3D shift and the implant axis inclination. For multiunit restorations with disparallel implants, polyvinyl siloxane materials should be considered. In addition, the effect size of a multivariate investigation should be reported.
种植治疗需要精确的印模。本体外研究旨在确定印模材料/方法、种植系统和种植体角度对印模转移精度的影响大小。
使用上颌模型，其中左、右上颌骨各有三个 BEGO 和三个 Straumann 种植体（角度为 0°、15°和 20°），作为参考模型。使用两种印模技术（开放式托盘和闭合式托盘）检查了一种聚醚（Impregum Penta）和两种聚硅氧烷（Flexitime Monophase/Aquasil Ultra Monophase）。共制作了 60 个印模。使用坐标测量机测量 3D 移位、种植体轴倾斜和种植体轴旋转的目标变量。所有数据均进行四向方差分析。报告了效应大小（偏 eta 平方[η]）。
印模材料对 3D 移位和种植体轴倾斜偏差有显著影响（p 值分别为<.000），这两个因素的效应大小均非常大（3D 移位[η]=.599；种植体轴倾斜[η]=.298）。聚硅氧烷印模的转移精度最高。当种植体的角度较大时，种植体轴旋转偏差会更大。种植系统和印模方法显示出部分显著的变化（p 值分别为<.001-.639），但只有非常小的效应大小（η=.001-.031）。
印模材料对 3D 移位和种植体轴倾斜的准确性有最大的影响。对于多单位修复体中存在不平行种植体的情况，应考虑使用聚硅氧烷材料。此外，应报告多变量研究的效应大小。
