title: In vitro degradation of a poly(propylene fumarate)-based composite material.
abstract: We investigated the in vitro degradation of a novel degradable polymeric composite material being developed to function as a temporary replacement for trabecular bone. This material is based on a mixture of poly(propylene fumarate) cross-linked by N-vinyl-pyrrolidone and includes sodium chloride and beta-tricalcium phosphate. Using an in vitro test in simulated body fluids, the compressive strengths and compressive moduli of two composite materials increased with degradation time and remained above the minimum values acceptable for trabecular bone substitutes. A compressive strength of 21.3 (+/- 0.4) MPa and a compressive modulus of 696 (+/- 53) MPa were measured after twelve weeks for a composite material with initial strength of 18.0 (+/- 4.6) MPa and initial modulus of 113 (+/- 40) MPa. This unexpected phenomenon may prove to be useful for orthopaedic applications.
authors.affiliation: Department of Orthopaedic Surgery, Wilford Hall Medical Center, Lackland Air Force Base, San Antonio, Texas, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Yaszemski
authors.forename: R G
authors.initials: RG
authors.lastname: Payne
authors.forename: W C
authors.initials: WC
authors.lastname: Hayes
authors.forename: R
authors.initials: R
authors.lastname: Langer
authors.forename: A G
authors.initials: AG
authors.lastname: Mikos
mesh_terms: D001672:Biocompatible Materials; D001843:Bone Cements; D004355:Drug Stability; D005650:Fumarates; D006801:Humans; D008855:Microscopy, Electron, Scanning; D011126:Polypropylenes
chemical_list: D001672:Biocompatible Materials; D001843:Bone Cements; D005650:Fumarates; D011126:Polypropylenes; C097850:poly(propylene fumarate)