No abstract

In the field of bone defect repair, gradient porous scaffolds have received increased attention because they provide a better environment for promoting tissue regeneration. In this study, we propose an effective method to generate bionic porous scaffolds based on the TPMS (triply periodic minimal surface) and SF (sigmoid function) methods. First, cortical bone morphological features (e.g., pore size and distribution) were determined for several regions of a rabbit femoral bone by analyzing CT-scans. A finite element method was used to evaluate the mechanical properties of the bone at these respective areas. These results were used to place different TPMS substructures into one scaffold domain with smooth transitions. The geometrical parameters of the scaffolds were optimized to match the elastic properties of a human bone. With this proposed method, a functional gradient porous scaffold could be designed and produced by an additive manufacturing method.

No abstract

Enterocutaneous fistulas (ECFs) are great challenges during the open abdomen. The loss of digestive juice, water-electrolyte imbalance and malnutrition are intractable issues during management of ECF. Techniques such as “fistula patch” and vacuum-assisted closure therapy have been applied to prevent contamination of open abdominal wounds by intestinal fistula drainage. However, failures are encountered due to high-output fistula and anatomical complexity. Here, we report 3D-printed patient-personalized fistula stent for ECF treatment based on 3D reconstruction of the fistula image. Subsequent follow-up demonstrated that this stent was well-implanted and effective to reduce the volume of enteric fistula effluent.