3D-printed TPMS-structured hybrid PLA/MgTiO scaffolds: Synergizing bioactivity and antibacterial performance for bone regeneration.

Bone repair and tissue engineering require biomaterials that offer both mechanical stability and biocompatibility. Titanium is renowned for its mechanical durability but has limited bioactivity, whereas magnesium offers high bioactivity but degrades too quickly. This study develops a novel hybrid scaffold using fused filament fabrication (FFF) to combine polylactic acid (PLA) with magnesium titanate (MgTiO). This approach aims to integrate the benefits of both materials into a PLA/MgTiO scaffold structured with TPMS. The research focuses on a detailed analysis of the scaffold's mechanical, thermal, and biological properties. Thermal analysis revealed that the addition of MgTiO raised the decomposition temperature of the PLA scaffold from 320 °C to 338 °C, enhancing its thermal stability. The inclusion of MgTiO in PLA resulted in a 7.55 % increase in compressive strength and a 27.46 % improvement in compressive modulus. The scaffold's surface, initially hydrophobic with a contact angle of 94.2°, became more hydrophilic, with the contact angle decreasing to 76.8. Furthermore, the scaffold exhibited enhanced bioactivity, as evidenced by increased hydroxyapatite formation during a 24-day immersion in simulated body fluid (SBF). In vitro studies showed that MgTiO promoted the growth of human mesenchymal stem cells (MSCs) and facilitated the differentiation of MSCs into osteoblasts. The scaffolds also exhibited strong antibacterial activity against Escherichia coli (E. coli). Integrating MgTiO not only enhances bioactivity, but also improves surface properties, making these scaffolds promising for bone regeneration and tissue engineering applications.