| [ Summary ] |
In recent years, nanoindentation has emerged as a powerful technique for investigating the micromechanical properties of bone. With nanoindentation measurements, an indenter penetrates the bone while the reaction forces and the depth of penetration are recorded. From this data, parameters related to the elastic modulus and hardness of the indented region can be determined. To address these issues, our research group measured the elastic modulus and hardness of vertebral shells in three bovine vertebrae using nanoindentation. Nanoindentation testing was used to simultaneously measure the load and displacement of a Berkovich indenter pressed at 100 mN into the bone specimen. An elastic modulus was calculated from the unloading curve, while hardness was defined as the maximum applied load divided by the surface area of the indentation. To compare the mechanical properties of other cortical bone, we also measured the elastic modulus and hardness of the bovine tibial bone using nanoindentation. Cortical specimens were scanned with peripheral quantitative computed tomography to measure the bone mineral density (BMD). It was found that a correlation existed between the elastic modulus and BMD of the cortical bone specimen. Likewise, a correlation existed between the hardness and BMD of the cortical bone specimen. |