Effect of porosity of titanium web on cortical bone response

Abstract

Titanium fiber web (TW), which is produced by sintering intertwined thin titanium fibers, is nondegradable three-dimensional scaffold material graft substitutes.TW has sufficient stiffness and elasticity for role and is bone compatible and easy to handle during surgery. We aimed to evaluate the influence of the differences of porosities of TWs on bone formation inside the TWs. Three types of TWs with different volumetric porosity, 60%, 73% and 87%, with a fiber diameter of 50μm were used. The TW was height of 4 mm, width of 4mm and thickness of 2 mm. SEM views of TWs indicated that the mean pore size of the TW was approximately 100-150 μm for 60% porosity TW, 200-250μm for 73% porosity TW and 300-350 μm for 87% porosity TW. Each TW was inserted into the cortical bone of rabbit tibiae. After 12 weeks of implantation, histological evaluation was performed. There are no distinct differences on the overall cortical bone response to TWs with three different porosities. Some TWs are embedded in the cortical part of tibiae of rabbits. Almost complete bone ingrowth was observed in the space of all TWs. For TW with 60% porosity, bone formation in the part of TW which is located in medullary cavity was recognized. It is concluded that TW is expected to be useful as a non-resorbable three-dimensional scaffold in regenerative medicine. More researches for clinical application of TW are the next series of our studies. © 2012 The Hard Tissue Biology Network Association.