Biaxial mechanics of 3D fiber deposited ply-laminate scaffolds for soft tissue engineering part I: Experimental evaluation

High throughput computational evaluation of how scaffold architecture, material selection, and loading modality influence the cellular micromechanical environment in tissue engineering strategies

“… 42 In brief, the unit cell is an idealized geometry of a three‐dimensional fiber deposition (3DF), angle‐ply scaffold which has previously demonstrated anisotropic material properties similar to the most relevant properties of native AF tissue (Figure 1A ). 32 , 36 The unit cell model was parametrized based on scaffold architecture, materials, and loading. Base parameter values of all scaffold parameters are summarized in Table 1 .…”

“… Scaffold model for the base geometry showing, A, the previously validated angle‐ply fiber scaffold 32 ; B, the double unit cell of the fiber scaffold with the definition of fiber angle (Θ); C, the final unit cell including the hydrogel infill showing the FE mesh and region of interest (ROI) for cellular micromechanical environment (CME) evaluation; and D, tri‐axial loading definitions of axial strain ( ε a ), circumferential strain ( ε c ), and radial pressure ( σ r ). The x‐, y‐, and z‐directions represent the axial, circumferential, and radial directions of the intervertebral disc (IVD), respectively …”

“…Scaffold fiber angles (Θ) ranging from 30° (increased biaxial asymmetry as compared to base model) to 45° (biaxial symmetry) were considered. The fiber spacing ( S ) in the scaffold was ranged from 0.6 to 1.4 mm, in increments of 0.1 mm and the fiber diameter ( D ) was studied from 0.20 to 0.45 mm (based on the range of common polymer fiber diameters produced via 3DF 32 , 49 , 50 , 51 ). Finally, the relative cell size was progressively increased to 10 times the original size.…”

“…A ubiquitous strategy within the TE community is to fabricate composite constructs consisting of a biodegradable scaffold with a cell‐laden matrix. Such TE scaffolds have been engineered to replicate specific tissue‐level material properties of various musculoskeletal tissues, 29–31 including AF 32,33 . However, these scaffolds do not necessarily ensure that the mechanical loads induced at the cellular level are sufficient to drive cell survival, proliferation, and ECM formation.…”

“…Such TE scaffolds have been engineered to replicate specific tissue‐level material properties of various musculoskeletal tissues, 29 , 30 , 31 including AF. 32 , 33 However, these scaffolds do not necessarily ensure that the mechanical loads induced at the cellular level are sufficient to drive cell survival, proliferation, and ECM formation. The relationship between tissue‐level loading and the cellular micromechanical environment (CME) is, therefore, essential to furthering our understanding of how best to design TE scaffolds.…”