3D fiber deposited polymeric scaffolds for external auditory canal wall


The external auditory canal (EAC) is an osseocartilaginous structure extending from the auricle to the eardrum, which can be affected by congenital, inflammatory, and neoplastic diseases, thus reconstructive materials are needed. Current biomaterial-based approaches for the surgical reconstruction of EAC posterior wall still suffer from resorption (biological) and extrusion (synthetic). In this study, 3D fiber deposited scaffolds based on poly(ethylene oxide terephthalate)/poly(butylene terephthalate) were designed and fabricated to replace the EAC wall. Fiber diameter and scaffold porosity were optimized, leading to 200 ± 33 µm and 55% ± 5%, respectively. The mechanical properties were evaluated, resulting in a Young’s modulus of 25.1 ± 7.0 MPa. Finally, the EAC scaffolds were tested in vitro with osteo-differentiated human mesenchymal stromal cells (hMSCs) with different seeding methods to produce homogeneously colonized replacements of interest for otologic surgery. This study demonstrated the fabrication feasibility of EAC wall scaffolds aimed to match several important requirements for biomaterial application to the ear under the Tissue Engineering paradigm, including shape, porosity, surface area, mechanical properties and favorable in vitro interaction with osteoinduced hMSCs.

This study demonstrated the fabrication feasibility of outer ear canal wall scaffolds via additive manufacturing. Aimed to match several important requirements for biomaterial application to ear replacements under the Tissue Engineering paradigm, including shape, porosity and pore size, surface area, mechanical properties and favorable in vitro interaction with osteo-differentiated mesenchymal stromal cells.

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The Italian Ministry of University and Research (MIUR, PRIN 2010S58B38) and the Tuscany Region (Health Program 2009 and CUCCS 2014) are greatly acknowledged for funding this research. S.D. and D.P. would like to thank the ARPA Foundation young researchers’ award, Decree #21, 20 December 2011, Medicine Faculty, University of Pisa. This research project received support from the Dutch Province of Limburg. Dr. Delfo D’Alessandro (University of Pisa) is kindly acknowledged for his remarkable technical support to histologic analysis.

Author contributions

C.M., L.B., and S.D. designed the experiments. C.M., M.M., D.P., L.T., and S.D. performed the experiments. C.M., M.M., D.P., and L.T. analyzed the data. C.M., V.G., and S.D. drafted the manuscript. P.A.S., S.G., C.S., L.M., and S.B. provided reagents and tools.

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Correspondence to Serena Danti.

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Mota, C., Milazzo, M., Panetta, D. et al. 3D fiber deposited polymeric scaffolds for external auditory canal wall. J Mater Sci: Mater Med 29, 63 (2018). https://doi.org/10.1007/s10856-018-6071-3

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