Polylactic Acid/Calcium Silicate Composite Scaffold Fabricated by Selective Laser Sintering with Coordinated Regulation of Bioactivity Induction, Degradation, and Mechanical Enhancement

Developing a biomimetic porous composite scaffold with mechanical properties tailored to meet the requirements of bone defect repair, enhanced bioactivity, and controlled biodegradability is of great significance for effective bone regeneration. In this work, calcium silicate (CS, CaSiO₃) was introduced into polylactic acid (PLA) as an addition. A scaffold model was then constructed using triply periodic minimal surfaces (TPMS), and a PLA/CS composite scaffold was fabricated using selective laser sintering (SLS) technology. Among them, when the CS content was 5wt%, the compressive strength and modulus of the composite scaffold were 4.8 MPa and 52.1 MPa, respectively, which were 104.2% and 43.9% higher than those of the PLA scaffold. The mechanical strengthening can be attributed to the particle reinforcement effect caused by the inherent high stiffness of CS. Additionally, the incorporation of CS accelerates the degradation of the scaffold while enhancing its bioactivity. The composite scaffold also demonstrated favorable cell compatibility in in vitro tests, supporting its potential for biological integration. In summary, the PLA/CS composite scaffold with coordinated regulation of multiple properties is expected to become a potential choice for bone defect repair.