TY - JOUR
T1 - Fabrication of biodegradable polymer scaffolds to engineer trabecular bone
AU - Thomson, Robert C.
AU - Yaszemski, Michael J.
AU - Powers, John M.
AU - Mikos, Antonios G.
N1 - Funding Information:
This work was supported by grants from the following sources: National Science Foundation (BCS-9213197); Orthopaedic Research and Education Foundation (93-017); and a T.N. Law Fund for Biotechnology Research to AGM. We wish to thank Mr. David Ladd of the University of Texas-Houston Health Science Center for his assistance with the mechanical testing studies.
PY - 1995/1/1
Y1 - 1995/1/1
N2 - We present a novel method for manufacturing three-dimensional, biodegradable poly(DLlactic-co-glycolic acid) (PLGA) foam scaffolds for use in bone regeneration. The technique involves the formation of a composite material consisting of gelatin microspheres surrounded by a PLGA matrix. The gelatin microspheres are leached out leaving an open-cell foam with a pore size and morphology defined by the gelatin microspheres. The foam porosity can be controlled by altering the volume fraction of gelatin used to make the composite material. PLGA 50 : 50 was used as a model degradable polymer to establish the effect of porosity, pore size, and degradation on foam mechanical properties. The yield strengths and moduli in compression of PLGA 50: 50 foams were found to decrease with increasing porosity according to power law relationships. These mechanical properties were however, largely unaffected by pore size. Foams with yield strengths up to 3.2 MPa were manufactured. From in vitro degradation studies we established that for PLGA 50: 50 foams the mechanical properties declined in parallel with the decrease in molecular weight. Below a weight average molecular weight of 10 000 the foam had very little mechanical strength (0.02 MPa). These results indicate that PLGA 50 : 50 foams are not suitable for replacement of trabecular bone. However, the dependence of mechanical properties on porosity, pore size, and degree of degradation which we have determined will aid us in designing a biodegradable scaffold suitable for bone regeneration.
AB - We present a novel method for manufacturing three-dimensional, biodegradable poly(DLlactic-co-glycolic acid) (PLGA) foam scaffolds for use in bone regeneration. The technique involves the formation of a composite material consisting of gelatin microspheres surrounded by a PLGA matrix. The gelatin microspheres are leached out leaving an open-cell foam with a pore size and morphology defined by the gelatin microspheres. The foam porosity can be controlled by altering the volume fraction of gelatin used to make the composite material. PLGA 50 : 50 was used as a model degradable polymer to establish the effect of porosity, pore size, and degradation on foam mechanical properties. The yield strengths and moduli in compression of PLGA 50: 50 foams were found to decrease with increasing porosity according to power law relationships. These mechanical properties were however, largely unaffected by pore size. Foams with yield strengths up to 3.2 MPa were manufactured. From in vitro degradation studies we established that for PLGA 50: 50 foams the mechanical properties declined in parallel with the decrease in molecular weight. Below a weight average molecular weight of 10 000 the foam had very little mechanical strength (0.02 MPa). These results indicate that PLGA 50 : 50 foams are not suitable for replacement of trabecular bone. However, the dependence of mechanical properties on porosity, pore size, and degree of degradation which we have determined will aid us in designing a biodegradable scaffold suitable for bone regeneration.
KW - Biodegradable polymers
KW - Polymer processing
KW - Polymer scaffolds
KW - Tissue engineering
KW - Trabecular bone
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U2 - 10.1163/156856295X00805
DO - 10.1163/156856295X00805
M3 - Article
C2 - 7662615
AN - SCOPUS:0029176138
VL - 7
SP - 23
EP - 38
JO - Journal of Biomaterials Science, Polymer Edition
JF - Journal of Biomaterials Science, Polymer Edition
SN - 0920-5063
IS - 1
ER -