Effect of Surface Modification on Viability of L929 Cells on Zirconia Nanocomposite Substrat

Introduction: Zirconia bioceramic can be considered for metallic replacement in dental implant applications. A proper method of surface modification may promote better osseointegration.Methods: In study evaluated viability of fibroblast cell following surface treatment. Therefore, viability L929 cells were characterized using MTT assay and scanning electron microscopy.Results: The viability assessment determined significant differences A-Y-TZP20 without surface treatment as compared to laser surface treatment (B), laser surface treatment + hydroxyapatite-yttrium stabilized tetragonal zirconia nanocomposite coat (C) and control. This study demonstrated that L929 cells approximately proliferated and spread on A-Y-TZP20 nanocomposite disk in laser surface treatment(B), Laser surface treatment + hydroxiapatite-yttrium stabilized tetragonal zirconia nanocomposite coat (C) groups similar to control group.Conclusion: Laser surface treatment showed positive effect on the viability of L929 cells

Effect of Alumina Addition to Zirconia Nano-composite on Low Temperature Degradation Process and Biaxial Strength

Ceramic dental materials have been considered as alternatives to metals for dental implants application. In this respect, zirconia tetragonal stabilized with %3 yttrium, is of great importance among the ceramic materials for endosseous dental implant application. Because of its good mechanical properties and color similar to tooth. The aim and novelty of this study was to design and prepare Y-TZP nano-composite to reduce the degradation process at low temperature by alumina addition and maintaining submicron grain sized. Also, flexural strength of nano-composite samples was evaluated. Toward this purpose, alumina-Y-TZP nano-composites containing 0–30 vol% alumina (denoted as A-Y-TZP 0-30) were fabricated using α-alumina and Y-TZP nano-sized by sintering pressure less method. The synthesized samples were characterized using x-ray diffraction, field emission scanning electron microscopy equipped with energy dispersive x-ray spectroscopy techniques. Nano-composite samples with high density (≥96%) and grain sized of ≤ 400 nm was obtained by sintering at 1270 °C for 170 min. After low temperature degradation test (LTD), A-Y-TZP20 and A-Y-TZP30 not showed monoclinic phase and the flexural strength in all of samples were higher than A-Y-TZP0. It was concluded that the grains were remained in submicron sized and A-Y-TZP20 and A-Y-TZP30 did not present biaxial strength reduction after LTD test