Biomimetic Synthesis of Self-Assembled Mineralized Collagen-Based Composites for Bone Tissue Engineering - Biomimetics: Advancing Nanobiomaterials and Tissue Engineering - page 26

2.2.1.2 Hierarchical Organization of Natural Human Bone

The properties of bone are a list of apparent contradictions: strong but
not brittle, lightweight but solid enough to support tissues, mechanically
strong but porous, stable but capable of remodeling, and so on and so
forth. Seven levels of hierarchical organization of human long bone from
the molecular to the macroscopic scale were described by Weiner et al.
[13, 14], shown in Figure 2.1. The basic building block of the bone materi-
als is the mineralized collagen fi bril (level 2), which is composed of very

Level 7: Whole bone

0.5 cm

Level 6: Spongy vs Compact bone

10 μ m

Level 5: Cylindrical motifs: Osteons

Level 4: Fibril array patterns

200 nm

Level 3: Fibril array

200 nm

Level 2: Mineralized collagen fibril

100 nm 200 nm

Level 1: Major components

Figure 2.1 Schematic representation of the seven hierarchical levels of
organization of human long bone. Reprinted with permission from [14].