Taboas J M, Maddox R D, Krebsbach P H, Hollister S J
Department of Oral Medicine, Pathology and Oncology, School of Dentistry, University of Michigan, 1011 N University Ave, Room G-018, Ann Arbor 48109, MI, USA.
Biomaterials. 2003 Jan;24(1):181-94. doi: 10.1016/s0142-9612(02)00276-4.
Precise control over scaffold material, porosity, and internal pore architecture is essential for tissue engineering. By coupling solid free form (SFF) manufacturing with conventional sponge scaffold fabrication procedures, we have developed methods for casting scaffolds that contain designed and controlled locally porous and globally porous internal architectures. These methods are compatible with numerous bioresorbable and non-resorbable polymers, ceramics, and biologic materials. Phase separation, emulsion-solvent diffusion, and porogen leaching were used to create poly(L)lactide (PLA) scaffolds containing both computationally designed global pores (500, 600, or 800 microm wide channels) and solvent fashioned local pores (50-100 microm wide voids or 5-10 microm length plates). Globally porous PLA and polyglycolide/PLA discrete composites were made using melt processing. Biphasic scaffolds with mechanically interdigitated PLA and sintered hydroxyapatite regions were fabricated with 500 and 600 microm wide global pores. PLA scaffolds with complex internal architectures that mimicked human trabecular bone were produced. Our indirect fabrication using casting in SFF molds provided enhanced control over scaffold shape, material, porosity and pore architecture, including size, geometry, orientation, branching, and interconnectivity. These scaffolds that contain concurrent local and global pores, discrete material regions, and biomimetic internal architectures may prove valuable for multi-tissue and structural tissue interface engineering.
对支架材料、孔隙率和内部孔隙结构进行精确控制对于组织工程至关重要。通过将实体自由成型（SFF）制造与传统的海绵支架制造工艺相结合，我们开发了用于铸造支架的方法，这些支架具有设计和控制的局部多孔和整体多孔内部结构。这些方法与多种生物可吸收和不可吸收的聚合物、陶瓷及生物材料兼容。采用相分离、乳液-溶剂扩散和致孔剂浸出法制备了聚（L）丙交酯（PLA）支架，其包含通过计算设计的整体孔隙（宽500、600或800微米的通道）和溶剂形成的局部孔隙（宽50-100微米的空隙或长5-10微米的平板）。通过熔融加工制备了整体多孔的PLA以及聚乙醇酸/PLA离散复合材料。制备了具有机械相互交错的PLA和烧结羟基磷灰石区域且整体孔隙宽500和600微米的双相支架。制备了具有模仿人松质骨复杂内部结构的PLA支架。我们在SFF模具中采用浇铸的间接制造方法增强了对支架形状、材料、孔隙率和孔隙结构的控制，包括尺寸、几何形状、取向、分支和连通性。这些包含同时存在的局部和整体孔隙、离散材料区域以及仿生内部结构的支架可能对多组织和结构组织界面工程具有重要价值。
