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

• Published in: Acta biomaterialia 2009-06, Vol.5 (5), p.1775-1784
• Main Authors: Schneider, Oliver D., Weber, Franz, Brunner, Tobias J., Loher, Stefan, Ehrbar, Martin, Schmidlin, Patrick R., Stark, Wendelin J.
• Format: Article
• Language: English
• Subjects: Animals; Biocompatible Materials - pharmacology; Body Fluids; Bone regeneration; Bone Substitutes - pharmacology; Calcification, Physiologic - drug effects; Calcium Phosphates - chemical synthesis; Cotton Fiber; Electrospinning; Lactic Acid - chemical synthesis; Materials Testing; Microscopy, Electron, Scanning; Nano calcium phosphate; Nanocomposites - chemistry; Osteogenesis - drug effects; PLGA; Pliability - drug effects; Polyglycolic Acid - chemical synthesis; Rabbits; Skull - diagnostic imaging; Skull - drug effects; Skull - pathology; Skull - surgery; Temperature; Tissue Scaffolds; X-Ray Microtomography
• ISSN: 1742-7061; 1878-7568
• DOI: 10.1016/j.actbio.2008.11.030

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.