Flow performance of porous implants with different geometry: Line, surface, and volume structures.

Additive manufacturing has enormous advantage of personalized adaptation. Particularly, porous implants have been widely used in clinical practice. Porous implant has the advantages and abilities to promote tissue growth and mass transfer, which are closely related to pore morphology. The purpose of this study is to investigate the effects of three porous structures, i.e., line structure, surface structure, and volume structure, on the flow properties of implants at different porosity. Therefore, a unit cell was selected from each type of structure (oct truss [OT], gyroid [G], and schwarz p [P]) as a typical cell, where OT is a line structure, G is a surface structure, and P is a volume structure. The scaffolds with different porosity of these cells were customized, and the shape parameters were measured and calculated. Then, the flow performance of three different scaffolds in Dulbecco's modified Eagle's medium was simulated by using computational fluid dynamics, and the flow velocity, permeability, and wall shear stress, which can reflect their biological properties, were calculated and compared. The results showed that the pore shape and porosity of porous implants greatly affected the physical parameters and performance of structures. These findings will contribute to unit cell selection and future performance optimization of porous implants.