Piezoelectricity Promotes 3D-Printed BTO/β-TCP Composite Scaffolds with Excellent Osteogenic Performance

Piezoelectricity is reported to be able to promote bone scaffolds with excellent osteogenic performance. Herein, barium titanate/β-tricalcium phosphate (BTO/β-TCP) piezoelectric composite scaffolds were 3D printed, and their osteogenic performances were investigated in detail. The fabrication of BTO/β-TCP piezoelectric composite scaffolds employed cutting-edge DLP 3D printing technology. The scaffolds, featuring a triply periodic minimal surface (TPMS) design with a porosity of 60%, offered a unique structural framework. A comprehensive assessment of the composition, piezoelectric properties, and mechanical characteristics of the BTO/β-TCP scaffolds was conducted. Notably, an increase in the BTO volume fraction from 50 to 80 vol % within the scaffolds led to a reduction in compressive strength, decreasing from 2.47 to 1.74 MPa. However, this variation was accompanied by a substantial enhancement in the piezoelectric constant d₃₃, soaring from 1.4 pC/N to 21.6 pC/N. Utilizing mouse osteoblasts (MC3T3-E1) in a live/dead cell staining assay, under the influence of external ultrasound, demonstrated the commendable biocompatibility of these piezoelectric composite ceramic bone scaffolds. Furthermore, thorough analyses of alkaline phosphatase (ALP) activity and polymerase chain reaction (PCR) findings provided compelling evidence of the scaffolds' superior osteogenic properties, underpinning their effectiveness at the cellular protein and gene levels. In conclusion, this study offers a groundbreaking strategy for the employment of BTO/β-TCP piezoelectric composite scaffolds in bone implant applications, harnessing their unique blend of biocompatibility, piezoelectricity, and osteogenic potential.