1. 3D printing with star-shaped strands: A new approach to enhance in vivo bone regeneration
- Author
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Raymond Llorens, Santiago, Lehmann, Cyril, Thorel, Emilie, Benítez Iglesias, Raúl, Riveiro Rodríguez, Antonio, Pou Saracho, Juan María, Manzanares Céspedes, Maria Cristina, Franch Serracanta, Jordi, Canal Barnils, Cristina, Ginebra Molins, Maria Pau, Universitat Politècnica de Catalunya. Departament d'Enginyeria de Sistemes, Automàtica i Informàtica Industrial, Universitat Politècnica de Catalunya. Departament de Ciència i Enginyeria de Materials, Universitat Politècnica de Catalunya. BBT - Biomaterials, Biomecànica i Enginyeria de Teixits, Universitat Politècnica de Catalunya. ANCORA - Anàlisi i control del ritme cardíac, Mimetis Biomaterials, Institut de Recerca Sant Joan de Déu, Universidade de Vigo, Universitat de Barcelona, Universitat Autònoma de Barcelona, and Institut de Bioenginyeria de Catalunya
- Subjects
Bone Regeneration ,Tissue Scaffolds ,Enginyeria biomèdica [Àrees temàtiques de la UPC] ,3D printing ,Bone and Bones ,Bone regeneration ,Scaffold ,Biomimetic calcium phosphate ,Materials biomèdics ,Osteogenesis ,In vivo ,Printing, Three-Dimensional ,Animals ,Rabbits ,Biomedical materials ,Pore architecture - Abstract
Concave surfaces have shown to promote bone regeneration in vivo. However, bone scaffolds obtained by direct ink writing, one of the most promising approaches for the fabrication of personalized bone grafts, consist mostly of convex surfaces, since they are obtained by microextrusion of cylindrical strands. By modifying the geometry of the nozzle, it is possible to print 3D structures composed of non-cylindrical strands and favor the presence of concave surfaces. In this work, we compare the in vivo performance of 3D-printed calcium phosphate scaffolds with either conventional cylindrical strands or star-shaped strands, in a rabbit femoral condyle model. Monocortical defects, drilled in contralateral positions, are randomly grafted with the two scaffold configurations, with identical composition. The samples are explanted eight weeks post-surgery and assessed by µ-CT and resin-embedded histological observations. The results reveal that the scaffolds containing star-shaped strands have better osteoconductive properties, guiding the newly formed bone faster towards the core of the scaffolds, and enhance bone regeneration, although the increase is not statistically significant (p > 0.05). This new approach represents a turning point towards the optimization of pore shape in 3D-printed bone grafts, further boosting the possibilities that direct ink writing technology offers for patient-specific applications.
- Published
- 2021