3-D Analysis of Pore Structure of Porous Biomaterials Using Micro Focus X-Ray Computed Tomography

Abstract:

Generally, characterizations of pore structures of porous biomaterials are mainly based on 2-dimensional (2-D) analysis using cross sectional micrographs. However, interconnectivity of each pore may be more important factor, when tissue ingrowth into deeper pores is considered. In this paper, using micro-CT imaging with 3-D image processing software, analyses of porous material based on 3-demensional (3-D) geometrical considerations were successfully performed. Plasmasprayed porous titanium implant (PT) and four types of sintered porous titanium implants (ST50- 200, ST50-500, ST70-200, and ST70-500) that possess different porosities (50% and 70%) and pore sizes (200-500+m and 500-1500+m) were analyzed in this study. A micro focus X-ray computed tomography system was employed to acquire microstructural information from the porous implants. Using 3-D image processing software, we performed three types of 3-D analysis including detection of the dead space (% dead pore), analysis of interconnectivity by blocking the narrow pore throat with caliber less than 52 +m (% pore with narrow throat) and analysis of material construct by contracting thin strut with thickness less than 52 +m (% construct with thin strut). ST50S and ST50L possessed interconnected porous structure with thicker strut; however, pore throat was considered to be relatively narrow. On the other hand, PT implant possesses favorable interconnectivity despite its’ low porosity; however, relatively thin strut indicate the structural disadvantage for mechanical property. These results suggest that the 3-D analysis of pore and strut structure using micro focus X-ray computed tomography and 3-D image processing software will provide effective information to develop porous implant.

• Periodical: Key Engineering Materials (Volumes 309-311)
• Pages: 1095-1098
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.309-311.1095
• Online since: May 2006
• Authors: Mitsuru Takemoto, Shunsuke Fujibayashi, B. Otsuki, Tomiharu Matsushita, Tadashi Kokubo, Takashi Nakamura
• Keywords: Interconnectivity, Micro Focus X-Ray Computed Tomography, Porous, Titanium (Ti)

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