Department of Biomaterials, Radboudumc, Nijmegen, The Netherlands.
Orthopedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
J Biomed Mater Res A. 2018 Feb;106(2):500-509. doi: 10.1002/jbm.a.36245. Epub 2017 Oct 27.
Calcium phosphate cements (CPCs) are commonly used as bone substitute materials. However, their slow degradation rate and lack of macroporosity hinders new bone formation. Poly(dl-lactic-co-glycolic acid) (PLGA) incorporation is of great interest as, upon degradation, produces acidic by-products that enhance CPC degradation. Yet, new bone formation is delayed until PLGA degradation occurs a few weeks after implantation. Therefore, the aim of this study was to accelerate the early stage pore formation within CPCs in vitro. With that purpose, we incorporated the water-soluble porogen sucrose at different weight percentages (10 or 20 wt %) to CPC and CPC/PLGA composites. The results revealed that incorporation of sucrose porogens increased mass loss within the first week of in vitro degradation in groups containing sucrose compared to control groups. After week 1, a further mass loss was observed related to PLGA and CPC degradation. Macroporosity analysis confirmed that macroporosity formation is influenced by the dissolution of sucrose at an early stage and by the degradation of PLGA and CPC at a later stage. We concluded that the combination of sucrose and PLGA porogens in CPC is a promising approach to promote early stage bone tissue ingrowth and complete replacement of CPC through multimodal pore formation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 500-509, 2018.
磷酸钙骨水泥 (CPCs) 通常被用作骨替代材料。然而，其缓慢的降解率和缺乏大孔性阻碍了新骨的形成。聚 (DL-丙交酯-共-乙交酯) (PLGA) 的掺入具有很大的研究兴趣，因为在降解时会产生酸性副产物，从而增强 CPC 的降解。然而，新骨的形成会延迟到植入后几周 PLGA 降解时才发生。因此，本研究的目的是在体外加速 CPC 早期的孔形成。为此，我们将水溶性致孔剂蔗糖以不同的重量百分比（10 或 20wt%）掺入 CPC 和 CPC/PLGA 复合材料中。结果表明，与对照组相比，在含有蔗糖的组中，蔗糖致孔剂的掺入会在体外降解的第一周内增加质量损失。第 1 周后，观察到与 PLGA 和 CPC 降解相关的进一步质量损失。大孔率分析证实，大孔形成受到早期蔗糖溶解以及后期 PLGA 和 CPC 降解的影响。我们得出结论，将蔗糖和 PLGA 致孔剂结合到 CPC 中是一种很有前途的方法，可以通过多模式孔形成促进早期骨组织向内生长和 CPC 的完全替代。© 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 500-509, 2018.
