Chun Heoung-Jae, Shin Ha-Shik, Han Chong-Hyun, Lee Soo-Hong
School of Mechanical Engineering, Yonsei University, Seoul, Korea.
Int J Oral Maxillofac Implants. 2006 Mar-Apr;21(2):195-202.
The purpose of this study was to investigate the effect of 3 different abutment types on the stress distribution in bone with inclined loads using finite element analysis.
The 1-body, internal-hex, and external-hex implant systems were modeled to study the effect of abutment type on stress distribution in bone. The bone model used in this study comprised compact and spongious bone assumed to be homogeneous, isotropic, and linearly elastic.
In the case of the 1-piece implant, the load was transferred evenly not only in the implant system but also in bone. However, the maximum Von Mises stress generated in bone with the 1-piece implant was always higher than that generated with the internal-hex implant, regardless of load angle inclination. In the case of the internal-hex implant, the contact condition with friction between abutment and implant in the tapered joints and at abutment neck reduced the effect of bending caused by horizontal component of inclined load. The maximum Von Mises stress in bone was the highest for the external-hex implant.
It was found that the internal-hex implant system generated the lowest maximum Von Mises stresses for all loading conditions because of reduction of the bending effect by sliding in the tapered joints between the implant and abutment.
It was concluded that abutment type has significant influence on the stress distribution in bone because of different load transfer mechanisms and the differences in size of the contact area between the abutment and implant.
本研究旨在通过有限元分析，研究3种不同基台类型在倾斜载荷作用下对骨内应力分布的影响。
对一体式、内六角和外六角种植体系统进行建模，以研究基台类型对骨内应力分布的影响。本研究中使用的骨模型由致密骨和松质骨组成，假定其为均质、各向同性且线弹性的。
在一体式种植体的情况下，载荷不仅在种植体系统内均匀传递，在骨内也是如此。然而，无论载荷角度如何，一体式种植体在骨内产生的最大冯·米塞斯应力总是高于内六角种植体产生的应力。在内六角种植体的情况下，锥形接头处以及基台颈部基台与种植体之间有摩擦的接触条件，降低了倾斜载荷水平分量引起的弯曲效应。外六角种植体在骨内产生的最大冯·米塞斯应力最高。
研究发现，由于种植体与基台之间的锥形接头处滑动减少了弯曲效应，内六角种植体系统在所有加载条件下产生的最大冯·米塞斯应力最低。
得出结论，由于不同的载荷传递机制以及基台与种植体之间接触面积大小的差异，基台类型对骨内应力分布有显著影响。
