Prananingrum Widyasri, Naito Yoshihito, Galli Silvia, Bae Jiyoung, Sekine Kazumitsu, Hamada Kenichi, Tomotake Yoritoki, Wennerberg Ann, Jimbo Ryo, Ichikawa Tetsuo
Department of Oral and Maxillofacial Prosthodontics and Oral Implantology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan.
Biomed Mater. 2016 Feb 2;11(1):015012. doi: 10.1088/1748-6041/11/1/015012.
Porous titanium has long been desired as a bone substitute material because of its ability to reduce the stress shielding in supporting bone. In order to achieve the various pore structures, we have evolved a moldless process combined with a space holder technique to fabricate porous titanium. This study aims to evaluate which pore size is most suitable for bone regeneration using our process. The mixture comprising Ti powder, wax binder and PMMA spacer was prepared manually at 70 °C which depended on the mixing ratio of each group. Group 1 had an average pore size of 60 μm, group 2 had a maximum pore size of 100 μm, group 3 had a maximum pore size of 200 μm and group 4 had a maximum pore size of 600 μm. These specimens were implanted into rabbit calvaria for three and 20 weeks. Thereafter, histomorphometrical evaluation was performed. In the histomorphometrical evaluation after three weeks, the group with a 600 μm pore size showed a tendency to greater bone ingrowth. However, after 20 weeks the group with a pore size of 100 μm showed significantly greater bone ingrowth than the other groups. This study suggested that bone regeneration into porous titanium scaffolds is pore size-dependent, while bone ingrowth was most prominent for the group with 100 μm-sized pores after 20 weeks in vivo.
由于多孔钛能够减少支撑骨中的应力遮挡，长期以来一直被视作一种骨替代材料。为了实现各种孔隙结构，我们开发了一种结合空间保持技术的无模工艺来制造多孔钛。本研究旨在评估使用我们的工艺时哪种孔径最适合骨再生。将钛粉、蜡粘合剂和聚甲基丙烯酸甲酯间隔物的混合物在70°C下手动制备，具体温度取决于每组的混合比例。第1组的平均孔径为60μm，第2组的最大孔径为100μm，第3组的最大孔径为200μm，第4组的最大孔径为600μm。将这些标本植入兔颅骨中3周和20周。此后，进行组织形态计量学评估。在3周后的组织形态计量学评估中，孔径为600μm的组显示出骨长入更多的趋势。然而，20周后，孔径为100μm的组显示出比其他组明显更多的骨长入。本研究表明，多孔钛支架中的骨再生取决于孔径大小，而在体内20周后，孔径为100μm的组骨长入最为显著。
