Posted: May 22nd, 2023

Modelling of nanobiotissues for bone tissue reconstruction

Ordered classification of original bone Extracellular Matrix (ECM)

Bones are composite structures made of inorganic (mineral) and organic (protein) parts. Macroscopically, bones comprise of dense crust of cortical bones that offer support and protection, and a permeable cancellous bone tissue at the two edges, capable of optimizing weight transmission and minimizing friction at the end joints. The cortical bone comprises of repeating osteon components, whilst the cancellous bone comprises an interconnecting structure of trabeculae and bone marrow filled open spaces. The osteon and trabeculae units comprise of collagen fibres.

20 to 30 concentric fibre layers (lamellae) are located in the osteons, and positioned at approximately 45⁰ around the principal canal, containing nerves and blood vessels. The 100 to 2000nm fibres comprise collagen fibrils and the tertiary composition of collagen fibrils comprises a 67nm periodicity and 40nm openings within collagen particles (Rho, Kuhn-Spearing, & Zioupos 1998). The hydroxyapatite crystals are combined in the gaps within collagen particles and increase bone rigidity (Currey 2002). Bone structure properties are significantly dependent on the organization and structure of the cells and ECM, where ECM organization is hierarchical and covers various linear magnitude orders. Therefore, reconstruction and repair of bone defects necessitate advanced approaches that are responsible for all scales in the hierarchy.