Elastic, Viscoelastic, and Plastic Mechanical Properties of Bone Tissue at the Implant Interface

Introduction: Active bone remodeling characterizes the bone-implant interface [1]. The damaged interfacial bone during vigorous implantation surgery is resorbed and new bone formation develops adjacent the implant surface. The newly formed bone tissue has immature collagen and less mineralization, which may provide its mechanical properties differently from those of the pre-existing old bone tissue [2,3]. In this study, we hypothesized that tissue properties of the pre-existing old bone would be reliable references to compare with those of the newly formed bone at the bone-implant interface to investigate healing status of an implant system. Nanoindentation has been widely used to assess elastic modulus and plastic hardness of bone at the tissue level. Recently, it has been indicated that this technology can be applied to measure viscoelastic properties of bone tissues at various anatomical locations of different species [4,5]. Thus, the objective of this study was to examine tissue age dependent changes of mechanical properties of bone tissue at the implant interface during post-implantation healing.