title: A study on improving mechanical properties of porous HA tissue engineering scaffolds by hot isostatic pressing.
abstract: Various interconnected porous hydroxyapatite (HA) ceramic scaffolds are universally used to induct the tissue growth for bone repair and replacement, and serve to support the adhesion, transfer, proliferation and differentiation of cells. Impregnation of polyurethane sponges with a ceramic slurry is adopted to produce highly porous HA ceramic scaffolds with a 3D interconnected structure. However, high porosity always accompanies a decrease in the strength of the HA ceramic scaffolds. Therefore, it is significant to improve the strength of the HA ceramic scaffolds with highly interconnected porosity so that they are more suitable in clinical applications. In this work, highly porous HA ceramic scaffolds are first produced by the polymer impregnation approach, and subsequently further sintered by hot isostatic pressing (HIP). The phase composition, macro- and micro-porous structure, sintering and mechanical properties of the porous HA scaffolds are investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), nanoindentation analysis and compressive test. The experimental results show that the nanohardness and compressive strength of HIP-sintered porous HA ceramics are higher than those of commonly sintered HA scaffolds. The HIP technique can effectively improve the sintering property and densification of porous HA ceramic scaffolds, so inducing an increase in the compression strength.
authors.affiliation: The Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Suguang
authors.initials: S
authors.lastname: Xiao
authors.forename: Xiong
authors.initials: X
authors.lastname: Lu
authors.forename: Jianxin
authors.initials: J
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Weng
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D018929:Cell Culture Techniques / Q000379:methods*; D002516:Ceramics / Q000737:chemistry; D019245:Compressive Strength; D017886:Durapatite / Q000737:chemistry*; D004548:Elasticity; D006244:Hardness; D006358:Hot Temperature; D008422:Materials Testing; D016062:Porosity; D011312:Pressure; D013314:Stress, Mechanical; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D017886:Durapatite