RESUMO
BACKGROUND: Dental Mesenchymal stem cells has prompted great for cell-based therapeutics. But no one knows for sure what the true potential of these cells, since most of the studies were done in isolation, using as source, different donors or different cell processing conditions. MATERIAL AND METHODS: An enriched population of cells positive for CD146, STRO-1, and CD90 was isolated of third molars teeth indicated for extraction of patient with of 16 years old. Analysis of cell kinetics, and subcellular tests were performed to assess the presence of minor and trace elements by using synchrotron radiation x-ray fluorescence microscopy. RESULTS: In the cell kinetics assays, the enriched populations showed generally slower growth as compared to those that were non-enriched. In comparison between the pulp and papilla populations, the derived pulp grew more rapidly than that derived from the papilla. The CD90 + cells exhibited a smaller pulp area compared to other populations, but the papilla of these cells exhibited a larger area. The CD90 + cells exhibited higher amounts of P, S, Cl, K, and Ca, while the Cu and Zn exhibited more than CD146-. STRO1 - exhibited K and Cu. For both the pulp and the papilla, multipotent stem cells positive for all three markers were present. CONCLUSIONS: Although they have been obtained from the same tooth and donor, as well as were grown, the populations derived from these two tissues have different growth morphology and kinetics. The biochemical differences show different metabolic patterns, reflecting in part the growth differences. Key words:Synchrotron radiation, dental stem cells, mesenchymal stem cells, chemical composition.
RESUMO
The synthesis of calcium phosphate nanoparticles may include modifying agents to tailor particle size, reduce agglomeration and add specific functionalities. This study describes the synthesis of dicalcium phosphate dihydrate (DCPD) nanoparticles functionalized with triethylene glycol dimethacrylate (TEGDMA), added to one of the reacting solutions, with the purpose of reducing agglomeration and improving the compatibility with vinyl-based resin matrices. The nanoparticles were characterized by X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FTIR), elemental analysis, thermogravimetric analysis (TGA), transmission electronic microscopy (TEM), dynamic light scattering (DLS), and surface area (BET). As controls, proprietary DCPD nanoparticles and nanoparticles synthesized without the addition of TEGDMA ("bare") were subjected to the same analytical methods. XRD revealed a similar crystalline structure of the synthesized materials in comparison to the proprietary nanoparticles. The presence of a TEGDMA layer was confirmed by elemental analysis and TGA, corresponding to a mass fraction of 8.5%. FTIR analysis of the functionalized nanoparticles revealed the suppression of some absorbance bands found in the neat TEGDMA. A chemisorption mechanism between TEGDMA and the surface of primary particles by ion-dipole interaction involving TEGDMA oxyethylene, and also an interaction mechanism between the particle surface and terminal-CH3 groups are proposed. Functionalized nanoparticles showed 3 to 11 times higher surface area than the controls, in agreement with DLS data, indicating lower agglomeration.