Effects of 10-MDP calcium salt on osteoblasts and fibroblasts.

OBJECTIVE: 10-methacryloyloxidecyl dihydrogen phosphate monomer (10-MDP) is commonly used as a bonding monomer in universal adhesives. Adhesives that contain this monomer can directly contact the surrounding periodontium due to the chemical binding of 10-MDP with hydroxyapatite in hard tissue to form calcium salts. However, the effect of these calcium salts on the periodontium in the case of subgingival fillings remains poorly understood. The objective of this study was to investigate effects of 10-MDP calcium salts on osteoblasts and fibroblasts in the periodontal tissues. METHODS: This study investigated the effects of different concentrations of 10-MDP calcium salts on the migration, proliferation, and differentiation of osteoblasts (MC3T3-E1) and fibroblasts (L929); additionally, the effect on apoptosis and matrix metalloproteinases (MMPs) expression in these cells was evaluated. Cell proliferation assay, alkaline phosphatase (ALP) activity assay, Western blotting, and quantitative real-time polymerase chain reaction were performed to determine the effects. RESULTS: The 10-MDP calcium salts (within a concentration of 0.5 mg/mL) showed no cytotoxicity and did not seem to influence the apoptosis, mitochondrial membrane potential, and reactive oxygen species (ROS) levels in the cells. However, they had an inhibitory effect on the secretion of MMP2 and MMP9 in the osteoblasts and fibroblasts. The ALP activity assay and Alizarin Red staining did not reveal any significant effects of the 10-MDP calcium salts on osteoblast differentiation. SIGNIFICANCE: These results suggest that applying 10-MDP-containing adhesives to subgingival fillings may be safe and beneficial for the periodontal tissues.

Sequential release of vascular endothelial growth factor-A and bone morphogenetic protein-2 from osteogenic scaffolds assembled by PLGA microcapsules: A preliminary study in vitro.

Bone regeneration is a complex process sequentially regulated by multiple cytokines at different stages. Vascular endothelial growth factor-A (VEGF-A) and bone morphogenetic protein-2 (BMP-2) are the two most important factors involved in this process, and the combination of the two can achieve better bone regeneration by coupling angiogenesis and osteogenesis. In this study, poly(lactic-co-glycolic acid) (PLGA) microspheres with core-shell structure (microcapsules) encapsulating VEGF-A or BMP-2 were prepared by coaxial channel injection and continuous fluid technology. The sequential release of two cytokines by microcapsules with different PLGA molecular weight and shell thickness and its performance in vitro were explored. It was demonstrated that the molecular weight of PLGA significantly affected the degradation and release kinetics of microcapsules, while the thickness of the shell can regulate the release in a finer level. VEGF-A encapsulated microcapsules with low molecular weight can induce vascular endothelial cells to form lumens structures in vitro at an early stage. And BMP-2 encapsulated microcapsules could promote osteogenic differentiation, but the effect could be delayed when the microcapsules were prepared with PLGA of 150 kDa. In conclusion, the core-shell PLGA microcapsules in this study can sequentially release VEGF-A and BMP-2 at different stages to simulate natural bone repair.