Abstract

The mechanical properties of composite material (such as bone) rely on the properties of its constituents as well as the interfacial bonding between them. Bone tissue is a porous mineralized matrix composite of inorganic bone mineral and organic constituents (collagen and non-collagenous proteins). The porosity of bone is due in part to the organic lined vascular channels (Haversian canals) which separates bone fluid spaces. Detergent treatments can be used to remove some of the organic layers and allows ions access to the mineralized matrix and the mineral-organic interface to examine the role of interfacial bonding on the mechanical properties of bone. This study demonstrates the importance of interfacial bonding between the mineral and organic constituents of bone through fluoride ion treatments. Fluoride ions alter interfacial bonding between the mineral and organic components of bone by exchanging with OH ions of bone mineral and creating an unfavourable electrostatic condition by a rise in pH. The reduction in interfacial bonding due to fluoride action lowers the mechanical properties of bone tissue.

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