Fabrication of a two-level tumor bone repair biomaterial based on a rapid prototyping technique.

Key Laboratory for Advanced Materials Processing Technology, Ministry of Education & Center of Organ Manufacturing, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
Biofabrication (Impact Factor: 3.71). 06/2009; 1(2):025003. DOI: 10.1088/1758-5082/1/2/025003
Source: PubMed

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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