RESUMO
Mesenchymal stem cells isolated from different dental tissues have been described to have osteogenic/odontogenic-like differentiation capacity, but little attention has been paid to the biochemical composition of the material that each produces. Here, we used Raman spectroscopy to analyze the mineralized materials produced in vitro by different dental cell populations, and we compared them with the biochemical composition of native dental tissues. We show that different dental stem cell populations produce materials that differ in their mineral and matrix composition and that these differ from those of native dental tissues. In vitro, BCMP (bone chip mass population), SCAP (stem cells from apical papilla), and SHED (stem cells from human-exfoliated deciduous teeth) cells produce a more highly mineralized matrix when compared with that produced by PDL (periodontal ligament), DPA (dental pulp adult), and GF (gingival fibroblast) cells. Principal component analyses of Raman spectra further demonstrated that the crystallinity and carbonate substitution environments in the material produced by each cell type varied, with DPA cells, for example, producing a more carbonate-substituted mineral and with SCAP, SHED, and GF cells creating a less crystalline material when compared with other dental stem cells and native tissues. These variations in mineral composition reveal intrinsic differences in the various cell populations, which may in turn affect their specific clinical applications.
Assuntos
Calcificação Fisiológica/fisiologia , Papila Dentária/citologia , Polpa Dentária/citologia , Gengiva/citologia , Células-Tronco Mesenquimais/metabolismo , Ligamento Periodontal/citologia , Dente Decíduo/citologia , Papila Dentária/fisiologia , Polpa Dentária/fisiologia , Gengiva/fisiologia , Humanos , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Ligamento Periodontal/fisiologia , Análise Espectral Raman , Dente Decíduo/fisiologiaRESUMO
Oxides are believed to be hydrophilic because of the strong affinity for hydroxylation at their surfaces. This letter explores the relationship between the hydroxylation of oxide surfaces and their resulting wettability. Here we demonstrate that hydroxyls increase the hydrophobicity, or reduce the wettability, of oxide surfaces by reducing the polar component of surface free energy. Using alumina as a model material, increased hydrophobicity with hydroxylation was confirmed experimentally and a correlation between the strength of the hydroxyl-driven hydrophobic response and surface treatment was demonstrated.