Fabrication of a two-level tumor bone repair biomaterial based on a rapid prototyping technique.
ABSTRACT After the removal of the giant cell tumor (GCT) of bone, it is necessary to fill the defects with adequate biomaterials. A new functional bone repair material with both stimulating osteoblast growth and inhibiting osteoclast activity has been developed with phosphorylated chitosan (P-chitosan) and disodium (1 --> 4)-2-deoxy-2-sulfoamino-beta-D-glucopyranuronan (S-chitosan) as the additives of poly(lactic acid-co-glycolic acid) (PLGA)/calcium phosphate (TCP) scaffolds based on a double-nozzle low-temperature deposition manufacturing technique. A computer-assisted design model was used and the optimal fabrication parameters were determined through the manipulation of a pure PLGA/TCP system. The microscopic structures, water absorbability and mechanical properties of the samples with different P-chitosan and S-chitosan concentrations were characterized correspondingly. The results suggested that this unique composite porous scaffold material is a potential candidate for the repair of large bone defects after a surgical removal of GCT.
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ABSTRACT: Translation of scaffold-based bone tissue engineering (BTE) therapies to clinical use remains, bluntly, a failure. This dearth of translated tissue engineering therapies (including scaffolds) remains despite 25 years of research, research funding totaling hundreds of millions of dollars, over 12,000 papers on BTE and over 2000 papers on BTE scaffolds alone in the past 10 years (PubMed search). Enabling scaffold translation requires first an understanding of the challenges, and second, addressing the complete range of these challenges. There are the obvious technical challenges of designing, manufacturing, and functionalizing scaffolds to fill the Form, Fixation, Function, and Formation needs of bone defect repair. However, these technical solutions should be targeted to specific clinical indications (e.g., mandibular defects, spine fusion, long bone defects, etc.). Further, technical solutions should also address business challenges, including the need to obtain regulatory approval, meet specific market needs, and obtain private investment to develop products, again for specific clinical indications. Finally, these business and technical challenges present a much different model than the typical research paradigm, presenting the field with philosophical challenges in terms of publishing and funding priorities that should be addressed as well. In this article, we review in detail the technical, business, and philosophical barriers of translating scaffolds from Concept to Clinic. We argue that envisioning and engineering scaffolds as modular systems with a sliding scale of complexity offers the best path to addressing these translational challenges.Tissue Engineering Part B Reviews 09/2011; 17(6):459-74. · 4.64 Impact Factor
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ABSTRACT: Bone defect repair is challenging in orthopaedic clinics. For treatment of large bone defects, bone grafting remains the method of choice for the majority of surgeons as it fills spaces and provides support for enhancing biological bone repair. There has been around 2.2 million bone grafts used annually worldwide . As therapeutic agents are desirable for enhancing bone healing, this study was designed to develop such a bioactive composite scaffold (PLGA/TCP/ICT) made of polylactide-co-glycolide (PLGA) and tricalcium phosphate (TCP) as a basic carrier incorporating a phytomolecule icaritin (ICT), i.e. a novel osteogenic exogenous growth factor. PLGA/TCP/ICT scaffolds were fabricated as PLGA/TCP (control group) and PLGA/TCP in tandem with low/mid/high dose ICT (LICT/MICT/HICT groups, respectively). To evaluate the in vivo osteogenic and angiogenic potentials of this bioactive scaffolds with slow release of osteogenic ICT, we established a 12 mm ulnar bone defect model in rabbits. X-ray and HR-pQCT results at weeks 2, 4 and 8 post-surgery showed more newly formed bone within bone defects implanted with PLGA/TCP/ICT scaffolds, especially PLGA/TCP/MICT scaffold. Histological results at weeks 4 and 8 also demonstrated more newly mineralized bone in PLGA/TCP/ICT groups, especially in PLGA/TCP/MICT group, correspondingly with more new vessels ingrowth. These findings may form a good foundation for potential clinical validation of this innovative bioactive scaffold incorporated with proper amount of osteopromotive phytomolecule ICT as a ready product for clinical applications.Acta biomaterialia 01/2013; · 5.09 Impact Factor
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ABSTRACT: Advances introduced by additive manufacturing have significantly improved the ability to tailor scaffolds architecture, enhancing the control over microstructural features. This has led to a growing interest in the development of innovative scaffold designs, as testified by the increasing amount of research activities devoted to the understanding of the correlation between scaffold topological features and its resulting properties, in order to find architectures capable to optimally trade-off between often conflicting requirements (such as the biological and the mechanical ones). Main aim of this article is to provide a review and propose a classification of existing methodologies for scaffold design and optimization in order to address key issues and help in deciphering the complex link between design criteria and resulting scaffold properties.Acta biomaterialia 10/2013; · 5.09 Impact Factor