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Hydroxyapatite fiber reinforced poly(alpha-hydroxy ester) foams for bone regenerationA process has been developed to manufacture biodegradable composite foams of poly(DL-lactic-co-glycolic acid) (PLGA) and hydroxyapatite short fibers for use in bone regeneration. The processing technique allows the manufacture of three-dimensional foam scaffolds and involves the formation of a composite material consisting of a porogen material (either gelatin microspheres or salt particles) and hydroxyapatite short fibers embedded in a PLGA matrix. After the porogen is leached out, an open-cell composite foam remains which has a pore size and morphology defined by the porogen. By changing the weight fraction of the leachable component it was possible to produce composite foams with controlled porosities ranging from 0.47 +/- 0.02 to 0.85 +/- 0.01 (n = 3). Up to a polymer:fiber ratio of 7:6, short hydroxyapatite fibers served to reinforce low-porosity PLGA foams manufactured using gelatin microspheres as a porogen. Foams with a compressive yield strength up to 2.82 +/- 0.63 MPa (n = 3) and a porosity of 0.47 +/- 0.02 (n = 3) were manufactured using a polymer:fiber weight ratio of 7:6. In contrast, high-porosity composite foams (up to 0.81 +/- 0.02, n = 3) suitable for cell seeding were not reinforced by the introduction of increasing quantities of hydroxyapatite short fibers. We were therefore able to manufacture high-porosity foams which may be seeded with cells but which have minimal compressive yield strength, or low porosity foams with enhanced osteoconductivity and compressive yield strength.
Document ID
Document Type
Reprint (Version printed in journal)
Thomson, R. C. (Institute of Biosciences and Bioengineering and Department of Chemical Engineering, Rice University Houston, TX 77005-1892, United States)
Yaszemski, M. J.
Powers, J. M.
Mikos, A. G.
McIntire, L. V.
Date Acquired
August 22, 2013
Publication Date
November 1, 1998
Publication Information
Publication: Biomaterials
Volume: 19
Issue: 21
ISSN: 0142-9612
Subject Category
Life Sciences (General)
Funding Number(s)
Distribution Limits
NASA Discipline Cell Biology
Non-NASA Center