The Structure of Bones Having or Lacking Osteocytes Exhibits Differences in Collagen Molecular Organization, Mineral Packing and the Organic-Inorganic Interfaces

Abstract

Bone is a fascinating biomaterial comprised mostly of type-I collagen fibers as an organic phase, apatite as an inorganic phase, with water molecules residing at the interfaces between these phases. They are hierarchically organized with minor constituents such as non-collagenous proteins, citrate ions and glycosaminoglycans into a composite structure that is mechanically durable yet contains enough porosity to accommodate cells and blood vessels. The nanometer scale organization of the collagen fibrous structure and the mineral constituents in bone were recently extensively scrutinized. However, molecular details at the lowest hierarchical level still need to be unraveled to better understand the exact atomic-level arrangement of all these important components in the context of the integral structure of the bone.