Long-term osteointegration of BMP-2 eluting hydroxyapatite scaffolds for bone tissue engineering

Bone tissue engineering;growth factors;Bone morphogenetic protein (BMP);hydroxyapatite;scaffolds

Maki, Aaron J. ; Wheeler ; Matthew B.

关键词: Bone tissue engineering;    growth factors;    Bone morphogenetic protein (BMP);    hydroxyapatite;    scaffolds;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/16015/1_Maki_Aaron.pdf?sequence=3&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Trauma, congenital defects, and tumor resections can result in discontinuity bone defects, which are typically treated through bone grafting. Potential limitations, such as donor site morbidity, make the development of synthetic implants with similar success to current techniques an attractive alternative for the repair of these structural defecits. Due to its chemical similarity, porous hydroxyapatite (HA) remains a candidate biomaterial for synthetic bone grafting. This thesis investigates a potential method to improve osteointegration of these hydroxyapatite bone scaffolds, the delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2). The objective of this study is to evaluate the effect of rhBMP-2 addition on scaffold osteointegration and degradation in a porcine animal model.Scaffolds were prepared and inserted into surgically induced defects in the mandibles of Yorkshire pigs in order to compare the addition of rhBMP-2-containg hydroxyapatite scaffolds to empty hydroxyapatite control scaffolds and hydroxyapatite scaffolds with empty gelatin microspheres at 6, 12, 24, and 48 weeks after insertion. Macroscale analysis of bone infiltration and scaffold degradation using micro-computed tomography indicated limited differences in bone and scaffold amounts between treatments. However, on the microscale, significant increases in bone infiltration into scaffold micropores with the rhBMP-2 treatment were observed through histological and scanning electron microscope analysis. In addition, significant degradation of the scaffold due to the physiological environment could be observed. We conclude that addition of rhBMP-2 into a porous hydroxyapatite scaffold may be advantageous to bone ingrowth due to improved osteointegration on the microscale.