In vivo and in vitro evaluation of flexible, cottonwool-like nanocomposites as bone substitute material for complex defects

Acta Biomater. 2009 Jun;5(5):1775-84. doi: 10.1016/j.actbio.2008.11.030. Epub 2008 Dec 11.


The easy clinical handling and applicability of biomaterials has become a focus of materials research due to rapidly increasing time and cost pressures in the public health sector. The present study assesses the in vitro and in vivo performance of a flexible, mouldable, cottonwool-like nanocomposite based on poly(lactide-co-glycolide) and amorphous tricalcium phosphate nanoparticles (PLGA/TCP 60:40). Immersion in simulated body fluid showed exceptional in vitro bioactivity for TCP-containing fibres (mass gain: 18%, 2 days, HAp deposition). Bone regeneration was quantitatively investigated by creating four circular non-critical-size calvarial defects in New Zealand White rabbits. The defects were filled with the easy applicable cottonwool-like PLGA/TCP fibres or PLGA alone. Porous bovine-derived mineral (Bio-Oss) was used as a positive control and cavities left empty served as a negative control. The area fraction of newly formed bone (4 weeks implantation) was significantly increased for TCP-containing fibres compared to pure PLGA (histological and micro-computed tomographic analysis). A spongiosa-like structure of the newly formed bone tissue was observed for PLGA/TCP nanocomposites, whereas Bio-Oss-treated defects afforded a solid cortical bone.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biocompatible Materials / pharmacology*
  • Body Fluids
  • Bone Substitutes / pharmacology*
  • Calcification, Physiologic / drug effects
  • Calcium Phosphates / chemical synthesis
  • Cotton Fiber*
  • Lactic Acid / chemical synthesis
  • Materials Testing*
  • Microscopy, Electron, Scanning
  • Nanocomposites / chemistry*
  • Osteogenesis / drug effects
  • Pliability / drug effects
  • Polyglycolic Acid / chemical synthesis
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Rabbits
  • Skull / diagnostic imaging
  • Skull / drug effects*
  • Skull / pathology*
  • Skull / surgery
  • Temperature
  • Tissue Scaffolds
  • X-Ray Microtomography


  • Biocompatible Materials
  • Bone Substitutes
  • Calcium Phosphates
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polyglycolic Acid
  • Lactic Acid
  • tricalcium phosphate