title: Bioabsorption of polylactides with different molecular properties.
abstract: In order to study the effects of factors governing the bioabsorption rate of polylactides, implantation tests were carried out in rabbits using various samples (20 x 10 x 2 mm3) differing in their chemical composition, residual monomer content, and molecular orientation. Copolymer samples with a higher lactic acid content showed a lower rate of absorption, whereas those with a higher unreacted monomer content were absorbed faster and showed a more drastic decrease in molecular weight. In contrast, degradation of the purified polymers was slow; the purified poly-L-lactide showed no weight change and a 50% reduction in molecular weight after 6 months of implantation. Scanning electron microscopy of the samples containing monomers showed a microporous structure extending from the surface to the inner region a few days after implantation, whereas the purified poly-L-lactide did not exhibit a microporous structural change even after 10 months of implantation.
authors: Department of Experimental Surgery, Kyoto University, Japan.
authors: T
authors: T
authors: Nakamura
authors: S
authors: S
authors: Hitomi
authors: S
authors: S
authors: Watanabe
authors: Y
authors: Y
authors: Shimizu
authors: K
authors: K
authors: Jamshidi
authors: S H
authors: SH
authors: Hyon
authors: Y
authors: Y
authors: Ikada
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D001673:Biodegradation, Environmental; D008297:Male; D008855:Microscopy, Electron, Scanning; D008968:Molecular Conformation; D008970:Molecular Weight; D009132:Muscles / Q000166:cytology; D011091:Polyesters / Q000378:metabolism*; D019736:Prostheses and Implants; D011817:Rabbits
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters