Preparation and performance evaluation of silica gel/tricalcium silicate composite slurry for 3D printing

Tricalcium silicate (C3S) has excellent biocompatibility and osteoconductivity, however its use in implant scaffold manufacture is primarily achieved through hand kneading, making it difficult to accurately control the resulting size and shape. 3D printing is a rapid prototyping technology that can be used to accurately manufacture scaffolds with complex shapes. However, tricalcium silicate reacts rapidly with water, and the slurry solidifies quickly, making it impossible to use it to synthesize complex structures by 3D printing. In this study, a Tricalcium Silicate / Silica gel slurry suitable for 3D printing was prepared by combining silica gel (SG) particles and hydroxypropyl methylcellulose (HPMC) with Tricalcium Silicate (C3S). The effect of HPMC solution concentration on powder agglomeration was studied. The printability of the C3S/SG slurry was tested by measuring the printable time. The mechanical properties and in vitro degradation rate of C3S/SG and changes in composition during the degradation process, were evaluated. The C3S/SG slurry was used for printing complex scaffolds with high precision. The study of the C3S/SG slurry provides a new approach for the manufacture of tricalcium silicate implants, which can be applied as prosthetic materials in orthopedics, dentistry, and other areas of clinical medicine.