title: Evaluating the effect of increasing ceramic content on the mechanical properties, material microstructure and degradation of selective laser sintered polycaprolactone/β-tricalcium phosphate materials.
abstract: Orthopaedic scaffold materials were fabricated from polycaprolactone (PCL) and composite PCL-β-tricalcium phosphate (PCL/β-TCP) powders using selective laser sintering (SLS). Incorporating β-TCP particles is desirable to promote osteogenesis. The effects of increasing β-TCP content on the material's mechanical properties and microstructure were evaluated. The wt% of β-TCP and PCL particle sizes were found to influence material microstructure and mechanical properties, with increasing ceramic content causing a small but significant increase in stiffness but significant reductions in strength. Degradation of materials was achieved using accelerated ageing methods. The influence of β-TCP content on degradation at 7 weeks was evaluated through changes in mechanical properties and microstructure, and the ceramic particles were found to reduce elastic modulus and increase strength. The results of this study highlight the influence of ceramic content on mechanical properties and degradation behaviour of PCL/β-TCP SLS materials, and indicate that these changes must be considered in the design of scaffolds for critical-sized defects.
authors.affiliation: Biomechanics Research Centre (BMEC), Mechanical and Biomedical Engineering, College of Engineering and Informatics, National University of Ireland, Galway, Ireland. Electronic address: heatherdoylenuig@gmail.com.
authors.forename: Heather
authors.initials: H
authors.lastname: Doyle
authors.affiliation: Biomechanics Research Centre (BMEC), Mechanical and Biomedical Engineering, College of Engineering and Informatics, National University of Ireland, Galway, Ireland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Lohfeld
authors.affiliation: Biomechanics Research Centre (BMEC), Mechanical and Biomedical Engineering, College of Engineering and Informatics, National University of Ireland, Galway, Ireland.
authors.forename: Peter
authors.initials: P
authors.lastname: McHugh
mesh_terms: D020341:Absorbable Implants; D018786:Bone Substitutes / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry; D055119:Elastic Modulus; D007834:Lasers; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010012:Osteogenesis; D011091:Polyesters / Q000737:chemistry; D011108:Polymers; D013696:Temperature; D023822:Tissue Engineering / Q000295:instrumentation; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D011091:Polyesters; D011108:Polymers; C485817:beta-tricalcium phosphate; C016240:polycaprolactone
keywords: Accelerated ageing; Bone tissue engineering; Degradation; Mechanical properties; Polycaprolactone; Selective laser sintering; β-Tricalcium phosphate