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PubMed · 9195331

Comparative bone healing near eroding polylactide-polyglycolide implants of differing crystallinity in rabbit tibial bone chambers.

H Winet·J Y Bao
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Abstract

Eroding poly(DL-lactide-co-glycolide) (PDLLG) washers and poly(L-lactide-co-glycolide) (PLLG) threads were observed chronically in vivo following loading in a bone chamber tibial implant (BCI). Images were recorded using intravital microscopy of the implanted rabbit. Erosion and bone healing, as represented by angiogenesis and osteogenesis, was determined from changes in projected area of observed polymer, vessels and bone, respectively. Erosion rates of the two polymers were significantly different. Healing adjacent to both polymers differed significantly from controls. Healing response to each polymer was also different, with the faster eroding PDLLG causing more deviation from normal osteogenesis and angiogenesis than did PLLG. It was speculated that the faster eroding polymer released macrophage-stimulating fragments earlier in the healing process, thus altering the normal macrophage-endothelial cell interaction which in turn affected angiogenesis-linked components of osteogenesis.

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Analysis of VarianceAnimalsBiodegradation, EnvironmentalCrystallizationFracture HealingMaterials TestingNeovascularization, PhysiologicOsteogenesisPolyestersPolyglycolic AcidProstheses and ImplantsRabbitsTibial FracturesComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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H Winet, J Y Bao. 1997. Comparative bone healing near eroding polylactide-polyglycolide implants of differing crystallinity in rabbit tibial bone chambers.. https://doi.org/10.1163/156856297x00425

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