Nikolov Svetoslav, Raabe Dierk
Max-Planck-Institut für Eisenforschung, Department of Microstructure Physics and Metal Forming, Düsseldorf, Germany.
Biophys J. 2008 Jun;94(11):4220-32. doi: 10.1529/biophysj.107.125567. Epub 2008 Feb 29.
We model the elastic properties of bone at the level of mineralized collagen fibrils via step-by-step homogenization from the staggered arrangement of collagen molecules up to an array of parallel mineralized fibrils. A new model for extrafibrillar mineralization is proposed, assuming that the extrafibrillar minerals are mechanically equivalent to reinforcing rings coating each individual fibril. Our modeling suggests that no more than 30% of the total mineral content is extrafibrillar and the fraction of extrafibrillar minerals grows linearly with the overall degree of mineralization. It is shown that the extrafibrillar mineralization considerably reinforces the fibrils' mechanical properties in the transverse directions and the fibrils' shear moduli. The model predictions for the elastic moduli and constants are found to be in a good agreement with the experimental data reported in the literature.
我们通过从胶原分子的交错排列到平行矿化纤维阵列的逐步均匀化，对矿化胶原纤维水平的骨弹性特性进行建模。提出了一种新的纤维外矿化模型，假设纤维外矿物质在力学上等同于包裹每个单独纤维的增强环。我们的建模表明，纤维外矿物质含量不超过总矿物质含量的30%，且纤维外矿物质的比例随整体矿化程度呈线性增长。结果表明，纤维外矿化显著增强了纤维在横向方向的力学性能以及纤维的剪切模量。发现弹性模量和常数的模型预测与文献报道的实验数据吻合良好。
