抄録
The primary objective of this study is to quantitatively evaluate the effects of bone tissue regeneration on the compressive mechanical behaviors of different types of artificial bone substitutes on the basis of in vivo experiment and image-based computational analysis.Three different kinds of porous bioceramics,namely,bioabsorbable HA,nonabsorbable HA and bioabsorbable β-TCP,were implanted into femurs of rabbits to examine bone regeneration behavior.After a certain period of implantation,each artificial bone was evaluated by compression mechanical test,structural analysis using μ-CT images and histological analysis.The μ-CT images were also used to construct finite element models of artificial bones with bone tissue ingrowth,and the finite element analysis was performed to characterize the compressive deformation mechanism.The computational results exhibited that at the beginning of implantation,high local concentrations of strain energy density were confirmed with less infiltration of bone tissue,on the contrary,such local concentrations were dramatically decreased after 48 weeks implantation because the pores were filled by regenerated bone tissues.It is thus noted that bone tissue ingrowth greatly changes the original porous structure,resulting in the dramatic change of the mechanical behavior.It is also noted that HA and β-TCP artificial bones exhibited different time-dependent behaviors of modulus,mainly depending on the bioabsorbability and rate of bone remodeling.It is also found that the computational results well coincided with the experimental.
