Scaffold

Linguistics

Engineering

Philosophy

Biomedical engineering

Materials science

Government (linguistics)

Surgery

Endocrinology

3D printing

Trabecular bone

Porosity

Economic shortage

3d printed

Implant

Stress shielding

Composite material

Structural engineering

Compression (physics)

Medicine

Modulus

Osteoporosis

Compressive strength

Journal of the mechanical behavior of biomedical materials/Journal of mechanical behavior of biomedical materials

Polymeric scaffolds provide several advantages when compared with other bone replacement and regenerating techniques. Namely, when compared with the current gold standard, bone autografts, there is no shortage of supply nor donor site morbidity. Contrarily to metallic implants, their mechanical properties are similar to those of cortical bone and they are biodegradable, therefore stress shielding is not expected to occur, and they will be gradually replaced by new bone tissue. Yet, there are still several challenges to overcome. After implantation scaffolds are subjected to dynamic loads, thus understanding polymeric scaffolds’ fatigue behavior plays a major role on the design of better products. In this work PLA scaffolds were manufactured using 3D printing with optimized parameters. A total of six configurations were tested under static and dynamic load conditions. Static compression testing and numerical simulation showed good correlation. Numerical simulation provided a viable resource for scaffold design and innovation. Four different low-cycle fatigue loads were applied, during 3600 cycles with a frequency of 0.25 Hz. While under dynamic conditions, with a maximum stress of 24 MPa and R = 0.1, the apparent compressive modulus reached 973 MPa, due to pore collapse. Even after 3600 cycles no significant fatigue damage mechanisms were found on low porosity scaffolds, rendering them useful for trabecular bone replacement under dynamic conditions.

Porosity and pore design influence on fatigue behavior of 3D printed scaffolds for trabecular bone replacement