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This study aimed to assess the mechanical and biological properties of bioactive glass (BG) coating on titanium (Ti). Bioinert Ti substrates were coated by BG to induce bioactivity to the surface. The sol-gel derived BG 58S sol was successfully prepared and coated on the abraded and blasted Ti surface using the sol-dip method. The characterization and cell study for all substrates' surface was carried out. Adhesion test confirmed that a firmly adhered BG coating layer was formed on the abraded and blasted Ti. The measured bonding strength between the coating and the blasted Ti substrate was the highest among all samples, which was 41.03±2.31 MPa. In-vitro cell viability and alkaline phosphatase activity (ALP) tests results also showed that BG coating on the Ti substrate improved the biological properties of the surface. The BG sol-dip coating method could be used to fabricate Ti substrate with a bioactive surface.

The clinical performance of dental composite restoration and its overall success are the result of physical, mechanical, and biological properties of the filling materials. The present study aimed to evaluate surface roughness, flexural properties, and cytotoxicity of two nanohybrids, namely, MI Gracefil and Herculite Ultra, and one nanoceramic dental resin composite DiamondLite. The surface roughness was assessed in two different grinding conditions. Flexural properties were measured by, the three-point bending test and the specimens’ fractured surface was analyzed by scanning electron microscopy. Weibull analysis was performed on the flexural strength data to determine the composites’ reliability. The cytotoxicity test was conducted on MC3T3-E1 cells by the MTS assay. The results showed that grinding conditions had a significant effect on all nanocomposites' surface roughness ( p < .05). Herculite Ultra had a significantly higher flexural strength (125.8 MPa) and flexural modulus (9.8 GPa) as compared to other two nanocomposites ( p < .05). Further, cytotoxicity results indicated that DiamondLite had the lowest cell viability during the incubation period ( p < .05). The current study, therefore, concluded that the evaluated nanocomposites showed satisfactory surface roughness. Herculite Ultra flexural properties and Weibull modulus results make it a reliable choice for direct restorations. The cell viability results also showed that all three nanocomposites had moderate cytotoxicity, making them acceptable for direct application in the mouth.

Yttria doped ZrO2 was deposited using an acidic zinc phosphatizing solution and the hydrothermal treatment. The coating was analyzed using a field emission-scanning electron microscope (FE-SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). A piston on three balls (ISO 6872) was used for the measurement of biaxial flexural strength. MC3T3-E1 cells attachment was evaluated by SEM, and cell proliferation were assessed using MTS assay™. SEM images confirmed that the zinc phosphate coating layer was successfully prepared and fully covered the surface. The measured adhesive strength of the coating was 79.11 MPa. In vitro cell study indicated that the coated sample had better cell morphology and proliferation. XRD and EDS analysis revealed that the crystalline coating structure indexed as zinc phosphate (hopeite) and the substrate was assigned as zirconia. The flexural strength test showed that the strength of zirconia before and after hydrothermal treatment was not affected.

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