Design and fabrication of a hybrid alginate hydrogel/poly(ε-caprolactone) mold for auricular cartilage reconstruction.

The aim of this study was to design and manufacture an easily assembled cartilage implant model for auricular reconstruction. First, the printing accuracy and mechanical properties of 3D-printed poly-ε-caprolactone (PCL) scaffolds with varying porosities were determined to assess overall material properties. Next, the applicability of alginate as cell carrier for the cartilage implant model was determined. Using the optimal outcomes of both experiments (in terms of (bio)mechanical properties, cell survival, neocartilage formation, and printing accuracy), a hybrid auricular implant model was developed. PCL scaffolds with 600 µm distances between strands exhibited the best mechanical properties and most optimal printing quality for further exploration. In alginate, chondrocytes displayed high cell survival (~83% after 21 days) and produced cartilage-like matrix in vitro. Alginate beads cultured in proliferation medium exhibited slightly higher compressive moduli (6 kPa) compared to beads cultured in chondrogenic medium (3.5 kPa, p > .05). The final auricular mold could be printed with 300 µm pores and high fidelity, and the injected chondrocytes survived the culture period of 21 days. The presented hybrid auricular mold appears to be an adequate model for cartilage tissue engineering and may provide a novel approach to auricular cartilage regeneration for facial reconstruction. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1711-1721, 2019.

A case report on a burned ear: Elastic memory of cartilage following temporary burial in a skin pocket.

Preserving exposed ear cartilage following a facial burn remains a major challenge. Normally, burned ear cartilage cannot be preserved in case of a full thickness burn of the overlying skin, and the cartilage has to be surgically removed. Sometimes, reconstructions can be performed at a later stage. We report a case where burned ear cartilage was directly surgically buried in a retroauricular skin pocket showing remarkable elastic memory: the buried ear cartilage, in this case the antihelix, regenerated over time and regained its original position protruding from the facial area. This case illustrates that ear cartilage is highly resilient, even when it has sustained significant thermal damage, and can be buried in a retroauricular skin pocket to avoid radical excision of the framework.