Wang Liping, Hsu Hung-Yao, Li Xu, Xian Cory J
The Third Affiliated Hospital of Southern Medical University, Orthopaedic Hospital of Guangdong Province, Guangzhou 510630, China; Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
School of Engineering, University of South Australia, Adelaide, SA 5095, Australia.
Biomed Res Int. 2016;2016:2735091. doi: 10.1155/2016/2735091. Epub 2016 Dec 15.
Bone cells are deformed according to mechanical stimulation they receive and their mechanical characteristics. However, how osteoblasts are affected by mechanical vibration frequency and acceleration amplitude remains unclear. By developing 3D osteoblast finite element (FE) models, this study investigated the effect of cell shapes on vibration characteristics and effect of acceleration (vibration intensity) on vibrational responses of cultured osteoblasts. Firstly, the developed FE models predicted natural frequencies of osteoblasts within 6.85-48.69 Hz. Then, three different levels of acceleration of base excitation were selected (0.5, 1, and 2 g) to simulate vibrational responses, and acceleration of base excitation was found to have no influence on natural frequencies of osteoblasts. However, vibration response values of displacement, stress, and strain increased with the increase of acceleration. Finally, stress and stress distributions of osteoblast models under 0.5 g acceleration in -direction were investigated further. It was revealed that resonance frequencies can be a monotonic function of cell height or bottom area when cell volumes and material properties were assumed as constants. These findings will be useful in understanding how forces are transferred and influence osteoblast mechanical responses during vibrations and in providing guidance for cell culture and external vibration loading in experimental and clinical osteogenesis studies.
骨细胞会根据它们所接受的机械刺激及其力学特性而发生变形。然而，成骨细胞如何受到机械振动频率和加速度幅值的影响仍不清楚。通过建立三维成骨细胞有限元（FE）模型，本研究调查了细胞形状对振动特性的影响以及加速度（振动强度）对培养的成骨细胞振动响应的影响。首先，所建立的有限元模型预测成骨细胞的固有频率在6.85 - 48.69赫兹范围内。然后，选择三种不同水平的基础激励加速度（0.5、1和2g）来模拟振动响应，发现基础激励加速度对成骨细胞的固有频率没有影响。然而，位移、应力和应变的振动响应值随着加速度的增加而增加。最后，进一步研究了在0.5g加速度下成骨细胞模型在 - 方向上的应力和应力分布。结果表明，当假设细胞体积和材料特性为常数时，共振频率可以是细胞高度或底部面积的单调函数。这些发现将有助于理解在振动过程中力是如何传递并影响成骨细胞的力学响应，以及为实验性和临床性骨生成研究中的细胞培养和外部振动加载提供指导。
