ABSTRACT The study investigates the influence of scaffold architecture and postprocessing, specifically heat treatment, on the mechanical and biological effectiveness of 3D‐printed polylactic acid (PLA) scaffolds. Cross‐patterned PLA scaffolds were printed at infill densities of 50%, 60%, and 70% and heat‐treated (HT) at varying temperature–time combinations to enhance crystallinity. The optimum condition was found to be 90°C for 120 min (HT‐120), which was chosen for further study. MTT assays using MG 63 osteoblast cells indicated that HT scaffolds, particularly with 70% infill density (HT90(120)‐70), showed significantly greater cell viability for 15 days than untreated scaffolds (UT‐70). The exchange of growth‐promoting nutrients among cells and heat treatment‐induced surface roughness enhances biocompatibility and cellular proliferation, crucial for bone regeneration. Mechanical tests showed that HT90(120)‐70 had nearly 20% higher yield strength than UT‐70 due to its enhanced crystallinity. Immersion of HT90(120)‐70 in physiological fluid for 15 days at 37°C did not significantly change yield strength compared to dry conditions, but post‐yield softening was observed in immersed scaffolds due to hydrolytic aging. Cyclic unloading‐reloading experiments under physiological conditions also demonstrated that HT90(120)‐70 shows greater resistance to deformation. The study reveals HT90(120)‐70 as a promising alternative scaffold for load‐bearing bone tissue engineering.
Chatterjee et al. (Sun,) studied this question.