ABSTRACT
The viscoelastic response of cortical bone to dynamic loads is important for bone’s physiological function and has been well documented in tension 1,2 compression 3 and torsional loading. 4,5 An increase in the strength and stiffness has been found with an increase in strain rate. Cortical bone tissue is a hierarchical ceramic composite of organic (30%) and inorganic constituents (70%). The organic matrix is composed of type I collagen and non-collagenous proteins. The inorganic mineral fibers are a hydroxyapatite-like material (HA). 6 Similar to other composites, the mechanical properties of bone have been shown to be dependent upon constituent volume fraction (density) and microstructural organization. In addition, we have demonstrated that interfacial bonding between the constituents of bone play an important role in providing the tensile and compressive strength and stiffness 7–9 and ultrasonic properties of cortical bone. 10 Interfacial bonding between the mineral and organic phases of bone is due, in part, to the strong adsorption affinity of hydroxyapatite for organic material. Mineral-organic interfacial bonding interactions reflects the quality of bone can be modified using ions such as fluoride or phosphate causing a permutation in the mechanical properties. The present study explores the effects of fluoride ion treatment on the compressive properties of cortical bone at different strain rates.
