Nanoscale Modeling of Morphological Disordering of Mineral Matrix Elements

The aim of the investigation was to develop a nanoscale functional model of bone matrix by combining its mineral elements into a single structure of mineral compounds, analyze the axial disorder effect of its elements on the effective elastic modules, and the distribution of stress-strain fields in a modeling structure using a finite element technique.

Materials and Methods. We proposed a new morphological nanoscale model of bone tissue (at the level of collagen fibrils) taking into account the mineral bridges between the bonds of hydroxyapatite crystals based on Denisov-Nikolsky’s model. We analyzed the effect of variation of morphological characteristics on local stress-strain state and mechanical properties of the representative bone volume element by means of the direct finite element simulation and homogenization.

Results. The increase of minerals disorder degree was found to be accompanied by the increase of strain and stress in a modeled structure. An elastic modulus value is slightly affected by disordering. The biological relevance of the phenomenon is in that the mineral disorder, regardless of the force direction, always increases the risk of bone matrix damage.

Conclusion. We developed a nanoscale functional model of bone matrix by combining its mineral elements into a single structure using mineral compounds. We determined the impact of axial disordering of it elements on effective elastic modules, and the distribution of stress-strain fields in a modeling structure using a finite element technique. The analysis of the results showed the qualitative relationship of the findings with the experiment.

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Semenov А.S., Grishchenko А.I., Melnikov B.E. Nanoscale Modeling of Morphological Disordering of Mineral Matrix Elements. Sovremennye tehnologii v medicine 2015; 7(4): 21, https://doi.org/10.17691/stm2015.7.4.03