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Nanometer‐size tin oxide particles (see Figure) with high thermal stability against particle growth have been synthesized. A low particle growth rate was achieved by doping SnO2 particles with rare earth ions during synthesis. This technology can be applied to modify the particle surface and then control growth rate and specific electric and catalyst properties, producing nanostructured materials with improved performance.

The aim of this study was to develop a highly porous calcium‐containing chitosan scaffold suitable for dentin regeneration. A calcium hydroxide (Ca[OH]2) suspension was used to modulate the degree of porosity and chemical composition of chitosan scaffolds. The chitosan solution concentration and freezing protocol were adjusted to optimize the porous architecture using the phase‐separation technique. Scanning electron microscopy/energy‐dispersive spectroscopy demonstrated the fabrication of a highly porous calcium‐linked chitosan scaffold (CH‐Ca), with a well‐organized and interconnected porous network. Scaffolds were cross‐linked on glutaraldehyde (GA) vapor. Following a 28‐day incubation in water, cross‐linked CH scaffold had no changes on humid mass, and CH‐Ca featured a controlled degradability profile since the significant humid mass loss was observed only after 21 (26.0%) and 28 days (42.2%). Fourier‐transform infrared spectroscopy indicated the establishment of Schiff base on cross‐linked scaffolds, along with calcium complexation for CH‐Ca. Cross‐linked CH‐Ca scaffold featured a sustained Ca2+ release up to 21 days in a humid environment. This porous and stable architecture allowed for human dental pulp cells (HDPCs) to spread throughout the scaffold, with cells exhibiting a widely stretched cytoplasm; whereas, the cells seeded onto CH scaffold were organized in clusters. HDPCs seeded onto CH‐Ca featured significantly higher ALP activity, and gene expressions for ALP, Col1, DMP‐1, and DSPP in comparison to CH, leading to a significant 3.5 times increase in calcium‐rich matrix deposition. In sum, our findings suggest that CH‐Ca scaffolds are attractive candidates for creating a highly porous and bioactive substrate for dentin tissue engineering.

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Titanium oxide (TiO2) thin films were obtained using the MOCVD method. In this report we discuss the properties of a film, produced using a ordinary deposition apparatus, as a function of the deposition time, with constant deposition temperature (90 °C), oxygen flow (7,0 L/min) and substrate temperature (400 °C). The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and visible and ultra-violet region spectroscopy (UV-Vis). The films deposited on Si (100) substrates showed the anatase polycrystalline phase, while the films grown on glass substrates showed no crystallinity. Film thickness increased with deposition time as expected, while the transmittance varied from 72 to 91% and the refractive index remained close to 2.6