Otsuki Bungo, Takemoto Mitsuru, Fujibayashi Shunsuke, Neo Masashi, Kokubo Tadashi, Nakamura Takashi
Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Shogoin, Kyoto 606-8507, Japan.
Biomaterials. 2006 Dec;27(35):5892-900. doi: 10.1016/j.biomaterials.2006.08.013. Epub 2006 Sep 1.
A porous structure comprises pores and pore throats with a complex three-dimensional (3D) network structure, and many investigators have described the relationship between average pore size and the amount of bone ingrowth. However, the influence of network structure or pore throats for tissue ingrowth has rarely been discussed. Four types of bioactive porous titanium implants with different pore sizes and porosities (6mm in diameter and 15 mm long) were analyzed using specific algorithms for 3D analysis of interconnectivity based on a micro focus X-ray computed tomography system. In vivo histomorphometric analysis was performed using the very same implants implanted into the femoral condyles of male rabbits for 6 and 12 weeks. This matching study revealed that more poorly differentiated pores tended to have narrow pore throats, especially in their shorter routes to the outside. In addition, for assessment of the entire implant, we proposed new two indices that represent the degree of bone and tissue ingrowth into an implant by considering the effect of narrow pore throats. Data obtained suggest that this sort of novel analysis is useful for evaluating bone and tissue ingrowth into porous biomaterials.
多孔结构由具有复杂三维（3D）网络结构的孔隙和孔喉组成，许多研究人员描述了平均孔径与骨长入量之间的关系。然而，网络结构或孔喉对组织长入的影响很少被讨论。使用基于微焦点X射线计算机断层扫描系统的特定算法，对四种不同孔径和孔隙率（直径6mm，长15mm）的生物活性多孔钛植入物进行了3D连通性分析。将相同的植入物植入雄性兔的股骨髁中6周和12周后进行体内组织形态计量学分析。这项匹配研究表明，分化较差的孔隙往往具有狭窄的孔喉，尤其是在其通向外部的较短路径中。此外，为了评估整个植入物，我们提出了两个新指标，通过考虑狭窄孔喉的影响来表示骨和组织向植入物内长入的程度。获得的数据表明，这种新颖的分析方法对于评估骨和组织向多孔生物材料内的长入是有用的。
