Tsuge Takuma, Hagiwara Yoshiyuki
Nihon University Graduate School of Dentistry, Tokyo, Japan.
Dent Mater J. 2009 Jul;28(4):373-81. doi: 10.4012/dmj.28.373.
To date, there is no evidence that internal anti-rotation configurations are better than external ones. The purpose of this study was to evaluate the effect of eccentric cyclic loading on abutment screw loosening in internal and external hexagon implants with either of these two screw materials, titanium (Ti) alloy versus gold alloy. The reverse torque value of the abutment screw was measured before (initial preload) and after loading (post-loading). The prepared assemblies were divided into four groups (A to D). Groups A and B used internal hex implants with gold alloy and Ti alloy abutment screws respectively. Groups C and D used external hex implants with gold alloy and Ti alloy abutment screws respectively. In all the groups, post-loading preload was significantly (p<0.05) higher than initial preload. Further, two-way ANOVA indicated that the implant-abutment connection did not have an effect, but the abutment screw material did. In particular, Ti abutment screws were less likely to come loose.
迄今为止，尚无证据表明内部抗旋转结构优于外部抗旋转结构。本研究的目的是评估这两种螺钉材料（钛（Ti）合金与金合金）中任一种在内部和外部六边形种植体中，偏心循环加载对基台螺钉松动的影响。在加载前（初始预紧力）和加载后测量基台螺钉的反向扭矩值。制备的组件分为四组（A至D）。A组和B组分别使用带有金合金和Ti合金基台螺钉的内部六边形种植体。C组和D组分别使用带有金合金和Ti合金基台螺钉的外部六边形种植体。在所有组中，加载后的预紧力均显著（p<0.05）高于初始预紧力。此外，双向方差分析表明种植体与基台的连接没有影响，但基台螺钉材料有影响。特别是，Ti基台螺钉松动的可能性较小。
