Effect of Pore Characteristics and Alkali Treatment on the Physicochemical and Biological Properties of a 3D-Printed Polycaprolactone Bone Scaffold

Abstract

Polycaprolactone scaffolds were designed and 3D-printed with different pore shapes (cube and triangle) and sizes (500 and 700 μm) and modified with alkaline hydrolysis of different ratios (1, 3, and 5 M). In total, 16 designs were evaluated for their physical, mechanical, and biological properties. The present study mainly focused on the pore size, porosity, pore shapes, surface modification, biomineralization, mechanical properties, and biological characteristics that might influence bone ingrowth in 3D-printed biodegradable scaffolds. The results showed that the surface roughness in treated scaffolds increased compared to untreated polycaprolactone scaffolds (R a = 2.3−10.5 nm and R q = 17− 76 nm), but the structural integrity declined with an increase in the NaOH concentration especially in the scaffolds with small pores and a triangle shape. Overall, the treated polycaprolactone scaffolds particularly with the triangle shape and smaller pore size provided superior performance in mechanical strength similar to that of cancellous bone. Additionally, the in vitro study showed that cell viability increased in the polycaprolactone scaffolds with cubic pore shapes and small pore sizes, whereas mineralization was enhanced in the designs with larger pore sizes. Based on the results obtained, this study demonstrated that the 3D-printed modified polycaprolactone scaffolds exhibit a favorable mechanical property, biomineralization, and better biological properties; therefore, they can be applied in bone tissue engineering.

Structural Mechanical Properties of 3D Printing Biomimetic Bone Replacement Materials

“…Generally, the sample with rhomboid holes did not have the ability to resist the compression load. It can be seen from the simulation results of the triangular hole sample that it has strong stability [ 45 ]. The overall compression displacement was minimal, and the stress distribution was more uniform and wider.…”

“…The stress distribution was uniform. It shows that the triangular hole sample has excellent resistance to axial compression load [ 45 ]. According to the axial compression simulation results of the rhomboid-hole sample, the bearing part of the sample would distort and deform under the condition of high porosity.…”

Design and synthesis of berberine loaded nano-hydroxyapatite/gelatin scaffold for bone cancer treatment

“…The rough surface and created porosity can contribute to the superior biological function of the scaffold and new bone growth. 45–47 As it can be seen, the pores were well distributed on the entire surface of the scaffold. Fig.…”

3D printing for bone regeneration: challenges and opportunities for achieving predictability

“…For polymer scaffolds, an increase in porosity or in pore size results in decreased mechanical properties, [67][68][69] while certain pore shapes can enhance compressive properties. 68,70 Pore shape has also an important impact on fluid circulation and cell seeding as previously demonstrated for gyroids pores.…”

“…For polymer scaffolds, an increase in porosity or in pore size results in decreased mechanical properties, [67][68][69] while certain pore shapes can enhance compressive properties. 68,70 Pore shape has also an important impact on fluid circulation and cell seeding as previously demonstrated for gyroids pores. 71,72 More recently, the emergence of triple periodic minimal surface (TPMS) scaffolds has seen the promise of further optimizing mechanical properties and biological performances of scaffolds for bone tissue engineering.…”