Knowledge Bank

As an engineering view, bone is a smart material whose structure and material properties can be controlled in response to the external loading to support and protect inner organs of the body. To achieve this, bone actively remodels its shape and material composition by removing old bone part and replacing it with new bone, which results in hierarchical structure and heterogeneity of bone. Even though the bone mineralization process plays a key role to modulate functional demands of bone, the underlying mechanism have not fully understood yet. In order to understand the mechanism, it is essential to examine bone quality depending on its tissue age. Moreover, due to its hierarchical structure, investigating it in a variety of scales are needed. Although the morphology and mechanical property of bone has been studied in a various scale, scrutinizing them together in its fibrillar scale has not been widely conducted. In this study, we used mandibular bone planted dental implant because the tissue age can be easily determined by the distance from the implant. We investigated the chronical changes of morphology and mechanical property in a fibrillar scale depending on the tissue age by employing bi-modal AFM technique. Finally, we successfully obtained topographic and its mechanical stiffness maps of the sample, which indicated that the old bone matrix showed more organized structure and higher stiffness when compared with the new bone matrix.