Effect of nanoparticulate CaCO3 on the biological properties of calcium silicate cement

Abstract

Abstract This study aimed to evaluate the effects of nanoparticulate CaCO3 (NPCC) on the biological properties of calcium silicate-based cements (CSCs), including their cytotoxicity, in vitro osteogenic activity, and interactions with rat femur tissue. The average size of NPCC was 90.3±26.0 nm. Cytotoxicity and osteogenic activity assays were performed using mouse bone marrow mesenchymal stem cells (BMSCs). BMSCs exposed to the eluents from CSC alone and CSC containing 2.5% NPCC (CSC-NPCC (2.5%)) for 24 h showed decreased cell viability at an eluent concentration of 75%. In contrast, CSC-NPCCs (5%, 10%, and 20%) did not affect cell viability. Regarding osteogenic activity, CSC-NPCCs (5%, 10%, 20%) enhanced the expression of osteogenic genes, including runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), type I collagen (COL-1), and osteocalcin (OCN). Additionally, mineralization in cell cultures was enhanced by CSC-NPCC, indicating that NPCC promoted the osteogenic activity of CSCs. In rat femurs, NPCC accelerates CSC resorption and stimulates bone regeneration at the implantation site. CSC alone occupied 22.2%±3.25% of the total femoral area at the implantation site, whereas CSC-NPCC (20%) occupied only 4%. These histological findings suggest that CSC-NPCC has potential as a biodegradable bone cement for use in bone defect areas that require regeneration.

Keywords

• Nanoparticulate calcium carbonate
• Calcium silicate cement
• Bone marrow mesenchymal stem cells
• Biocompatibility
• Osteogenic
• Bone regeneration