title: A functionally gradient variational porosity architecture for hollowed scaffolds fabrication.
abstract: This paper presents a novel continuous tool-path planning methodology for hollowed scaffold fabrication in tissue engineering. A new functionally gradient porous architecture is proposed with a continuous material deposition planning scheme. A controllable variational pore size and hence the porosity have been achieved with a combination of two geometrically oriented consecutive layers. The desired porosity has been achieved with consecutive layers by geometrically partitioning each layer into sub-regions based on the area and the tissue scaffold design constraints. A continuous, interconnected and optimized tool-path for layers has been generated for a three-dimensional biomaterial deposition/printing process. A zigzag pattern tool-path has been proposed for an accumulated sub-region layer, and a concentric spiral-like optimal tool-path pattern has been generated for the successive layer to ensure continuity along the structure. Three-dimensional layers, formed by the proposed tool-path plan, vary the pore size and the porosity based on the biological and mechanical requirements. Several examples demonstrate the proposed methodology along with illustrative results. Also a comparative study between the proposed design and conventional Cartesian coordinate scaffolds has been performed. The results demonstrate a significant reduction in design error with the proposed method. Moreover, sample examples have been fabricated using a micro-nozzle biomaterial deposition system, and characterized for validation.
authors: Department of Industrial Engineering, University at Buffalo, Buffalo, NY 14260, USA.
authors: A K M
authors: AK
authors: Khoda
authors: Ibrahim T
authors: IT
authors: Ozbolat
authors: Bahattin
authors: B
authors: Koc
mesh_terms: D000464:Alginates / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry; D017076:Computer-Aided Design; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D008953:Models, Anatomic; D016062:Porosity; D013131:Spine / Q000033:anatomy & histology; D023822:Tissue Engineering; D054457:Tissue Scaffolds
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D006603:Hexuronic Acids; D020100:Hydrogels; D020723:Glucuronic Acid