Chi Chih-Ching, Shen Yen-Wen, Hsu Jui-Ting, Fuh Lih-Jyh, Huang Heng-Li
Int J Oral Maxillofac Implants. 2024 Dec 11;39(6):209-216. doi: 10.11607/jomi.10877.
To perform a finite element analysis (FEA) and an in vitro experiment to investigate and compare the loading effects (effects on the implant and surrounding bone) of various customized angled abutments to commercial 15-degree angled abutments (control).
Four customized angled abutment models (21.9, 24.15, 20.22, and 33 degrees) were developed using CBCT images of incisor inclination measurements from patients of various age groups (20 to 23, 24 to 39, and 40 to 65 years). 3D maxillary bone models were created from the CBCT images of four individual patients: One patient from each age group with the respective average incisor inclination measurement and another patient with the overall average were selected. Then, FEA and in vitro strain gauge experiments were conducted by applying 100 N or 50 N of axial or oblique force to each model in order to assess the differences in stress/strain between the customized angled abutments (test) and the control in both the implants and surrounding bone.
Under axial loading, the stress values in the implant and surrounding bone were elevated due to the relatively higher angles of the customized angled abutments (21.9, 24.15, 20.22, and 33 degrees) compared to the control angled abutments. Under oblique loading, the control angled abutments exhibited higher stress values in both the implant and surrounding bone. For the in vitro experiment, there was no statistically significant difference in bone strain between the customized (21.9 degree) and the control angled abutments in axial loading. Nevertheless, the control angled abutment with oblique loading induced greater bone strains.
Customized angled abutments offer lower stress/strain under oblique loads but higher stress/strain under axial loads compared to the control abutments. Therefore, in the design and application of angled abutments, careful consideration of the occlusal load direction is important for achieving the biomechanical success of an implant.
进行有限元分析（FEA）和体外实验，以研究和比较各种定制角度基台与商用15度角度基台（对照）的加载效果（对种植体和周围骨的影响）。
利用不同年龄组（20至23岁、24至39岁和40至65岁）患者的门牙倾斜度测量的CBCT图像，开发了四种定制角度基台模型（21.9度、24.15度、20.22度和33度）。从四名个体患者的CBCT图像中创建三维上颌骨模型：从每个年龄组中选择一名具有各自平均门牙倾斜度测量值的患者，以及另一名具有总体平均值的患者。然后，通过对每个模型施加100 N或50 N的轴向或斜向力进行有限元分析和体外应变片实验，以评估定制角度基台（测试）与对照在种植体和周围骨中的应力/应变差异。
在轴向加载下，与对照角度基台相比，定制角度基台（21.9度、24.15度、20.22度和33度）的角度相对较高，导致种植体和周围骨中的应力值升高。在斜向加载下，对照角度基台在种植体和周围骨中均表现出较高的应力值。对于体外实验，在轴向加载下，定制（21.9度）角度基台与对照角度基台之间的骨应变没有统计学上的显著差异。然而，斜向加载的对照角度基台会引起更大的骨应变。
与对照基台相比，定制角度基台在斜向载荷下提供较低的应力/应变，但在轴向载荷下提供较高的应力/应变。因此，在角度基台的设计和应用中，仔细考虑咬合载荷方向对于实现种植体的生物力学成功很重要。
