A New Approach for Structure-Property Relations in Scaffold Design for Bone Tissue Engineering

该补助金为组织工程研究提供第一年的资金，旨在确定骨长入，初始支架微观结构和性能以及支架/组织复合材料性能之间的关系。 具体而言，其旨在回答以下问题：组织再生后支架中的骨填充百分比和支架/组织复合材料性能如何与初始机械性能相关，更重要的是与支架的初始微观结构相关？ 对于初始研究，将在体外构建代表支架/组织复合材料可能机械性能范围的设计空间。具有四种不同微观结构但均具有相同宏观结构的羟基磷灰石（HA）支架将被硬聚合物和软聚合物渗透，分别代表100%骨和结缔组织填充。 将对复合支架进行压缩测试，并为每种微结构提供一组机械性能的上限和下限。体外研究的结果将用于未来的体内研究;将检查的微结构子集植入猪下颌骨中，并评价骨长入和复合材料机械性能。 该研究有可能在骨支架结构-性能关系的基本理解方面取得重大进展。这项研究的临床和社会影响是显而易见的。有些人需要大规模的骨重建，包括老年人、口腔癌患者或遭受钝力创伤的人，如在伊拉克受伤的美国士兵。市场上没有合适的产品来满足这一需求;因此，这项工作的结果有可能显著改善临界尺寸骨缺损患者的生活质量。

This grant provides the first year of funding for tissue engineering research that aims to determine relationship between bone ingrowth, initial scaffold microstructure and properties, and scaffold/tissue composite properties. Specifically, it aims to answer the question: How does the percent bone fill in the scaffold after tissue regeneration and the scaffold/tissue composite properties correlate with initial mechanical properties, and more fundamentally with the initial microstructure of the scaffold? For the initial study, a design space will be constructed in vitro that represents the range of possible mechanical properties for the scaffold/tissue composites. Hydroxyapatite (HA) scaffolds with four different microstructures, but all with the same macrostructure, will be infiltrated with hard and soft polymers, representing 100% bone and connective tissue fill, respectively. Composite scaffolds will be tested in compression and will provide a set of upper and lower bounds on mechanical properties for each microstructure. The results from the in vitro study will feed into a future in vivo study; a subset of the microstructures examined will be implanted into a swine mandible and evaluated for bone ingrowth and composite mechanical properties. The research has the potential to make significant advances in the fundamental understanding of the structure-property relationships of bone scaffolds. The clinical and societal impact for the research is evident. There are people who are in need of massive scales of bone reconstruction including, for example, the elderly, those afflicted with oral cancer, or who have suffered blunt force trauma like the American soldiers injured in Iraq. There are no appropriate products on the market to fill this need; therefore, results derived from this work have the potential to significantly improve the quality of life for patients with critical-sized bone defects.