title: Reproducibility of ZrO2-based freeze casting for biomaterials.
abstract: The processing technique of freeze casting has been intensely researched for its potential to create porous scaffold and infiltrated composite materials for biomedical implants and structural materials. However, in order for this technique to be employed medically or commercially, it must be able to reliably produce materials in great quantities with similar microstructures and properties. Here we investigate the reproducibility of the freeze casting process by independently fabricating three sets of eight ZrO2-epoxy composite scaffolds with the same processing conditions but varying solid loading (10, 15 and 20 vol.%). Statistical analyses (One-way ANOVA and Tukey's HSD tests) run upon measurements of the microstructural dimensions of these composite scaffold sets show that, while the majority of microstructures are similar, in all cases the composite scaffolds display statistically significant variability. In addition, composite scaffolds where mechanically compressed and statistically analyzed. Similar to the microstructures, almost all of their resultant properties displayed significant variability though most composite scaffolds were similar. These results suggest that additional research to improve control of the freeze casting technique is required before scaffolds and composite scaffolds can reliably be reproduced for commercial or medical applications.
authors.affiliation: Materials Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA. Electronic address: snaleway@eng.ucsd.edu.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Naleway
authors.affiliation: Department of Forest Ecosystems and Society, Oregon State University, 321 Richardson Hall, Corvallis, OR 97331, USA. Electronic address: kate.fickas@oregonstate.edu.
authors.forename: Kate C
authors.initials: KC
authors.lastname: Fickas
authors.affiliation: Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA. Electronic address: ymaker@eng.ucsd.edu.
authors.forename: Yajur N
authors.initials: YN
authors.lastname: Maker
authors.affiliation: Materials Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA; Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA; Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA. Electronic address: mameyers@eng.ucsd.edu.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Meyers
authors.affiliation: Materials Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA; Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA. Electronic address: jmckittrick@eng.ucsd.edu.
authors.forename: Joanna
authors.initials: J
authors.lastname: McKittrick
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D054457:Tissue Scaffolds / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D015040:Zirconium; C028541:zirconium oxide
keywords: Bioinspired; Biomaterial; Freeze casting; Mechanical properties; Reproducibility; Statistical analysis