Clinic for Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
Int J Oral Maxillofac Implants. 2012 May-Jun;27(3):505-12.
The aim of this study was to examine the bending moments and fracture patterns of different zirconia abutments with internal implant-abutment connections after static loading and to compare their bending moments to those of internally connected titanium abutments.
Three types of customized zirconia abutments (Straumann CARES abutments/Straumann BL implants [T1], Astra ZirDesign abutments/Astra Micro Thread OsseoSpeed implants [T2], Zirabut prototype abutments/Straumann SP implants [T3]) and one type of customized titanium abutment (control group, Straumann CARES abutments/Straumann BL implants [C]) were included. All abutments were one-piece abutments with an internal implant-abutment connection and were customized to the same shape but featured different implant-abutment connection designs. For each group, 20 identical copies of a master abutment were fabricated and fixed on their corresponding implants. Half of the abutments in each group were left unrestored, and the other 10 received glass-ceramic crowns. Static loading was applied at a 30-degree angle to the palatal surface until failure, and bending moments were calculated. The type of failure was characterized visually by dismounting the abutments and by examination of cross-sections of the embedded specimens. The results were analyzed statistically.
The mean range of bending moments was higher for the unrestored groups (158.2 to 678.2 Ncm) than for the restored groups (117.9 to 419.4 Ncm). The highest mean bending moments were seen in the control group, both restored and unrestored (419.4/678.2 Ncm). Unrestored, T1 and T2 exhibited significantly higher bending moments than T3. This was also observed in the restored groups.
Both the abutment material and the implant-abutment connection design affected the bending moments of abutments after static loading. Internally connected zirconia abutments with horizontal mismatch to the implant exhibited significantly higher bending moments compared to those without horizontal mismatch.
本研究旨在检测不同内连接式氧化锆基台在静态负载下的弯曲力矩和断裂模式，并将其与内连接式钛基台的弯曲力矩进行比较。
纳入三种定制氧化锆基台（Straumann CARES 基台/Straumann BL 种植体 [T1]、Astra ZirDesign 基台/Astra Micro Thread OsseoSpeed 种植体 [T2]、Zirabut 原型基台/Straumann SP 种植体 [T3]）和一种定制钛基台（对照组，Straumann CARES 基台/Straumann BL 种植体 [C]）。所有基台均为内连接式一体式基台，且具有相同的形状，但连接设计不同。每组均制作 20 个相同的主基台并固定于相应种植体上。每组的一半基台不修复，另一半则修复上玻璃陶瓷冠。在颊面以 30°角施加静态负载直至基台破坏，并计算弯曲力矩。通过拆卸基台和检查嵌入样本的横截面，对破坏类型进行直观描述和分析。对结果进行统计学分析。
未修复组的平均弯曲力矩范围（158.2 至 678.2 Ncm）高于修复组（117.9 至 419.4 Ncm）。对照组（修复和未修复）的平均弯曲力矩最高（419.4/678.2 Ncm）。未修复、T1 和 T2 的弯曲力矩显著高于 T3，在修复组中也观察到这种情况。
基台材料和内连接设计均影响静态负载后基台的弯曲力矩。与无水平不匹配的基台相比，具有水平不匹配的内连接式氧化锆基台的弯曲力矩显著更高。
