Gali Sivaranjani, Gururaja Suhasini, Prabhu T Niranjana, Srinivasan Srikari
Department of Prosthodontics, Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bengaluru 560054, India.
Department of Aerospace Engineering, Auburn University, Auburn, AL 36849, USA.
Materials (Basel). 2023 Sep 8;16(18):6125. doi: 10.3390/ma16186125.
Conventional sintering methods of dental ceramics have limitations of high temperature and slow cooling rates with requirements of additional heat treatment for crystallization. Spark plasma sintering (SPS) is an emerging technique that has the potential to process dental restorations with dense microstructures and tailor-made clinically relevant properties with optimized processing parameters. This study explored the potential of the SPS of zirconia-reinforced fluormica glass (FM) for dental restorative materials.
FM glass frit was obtained through the melt-quench technique (44.5 SiO-16.7 AlO-9.5 KO-14.5 MgO-8.5 BO-6.3 F (wt.%)). The glass frit was ball-milled with 20 wt.% of 3 mol% yttria-stabilized zirconia (FMZ) for enhanced fracture toughness. The mixtures were SPS sintered at a pressure of 50 MPa and a heating rate of 100 °C/min for 5 min with an increase in temperature from 650-750 °C-850 °C-950 °C. Phase analysis was carried out using XRD and microstructural characterization with SEM. Micro-hardness, nano-indentation, porosity, density, indentation fracture toughness, and genotoxicity were assessed.
The increase in the SPS temperature of FMZ influenced its microstructure and resulted in reduced porosity, improved density, and optimal mechanical properties with the absence of genotoxicity on human gingival fibroblast cells.
牙科陶瓷的传统烧结方法存在高温和冷却速度慢的局限性，且需要额外的热处理来结晶。放电等离子体烧结（SPS）是一种新兴技术，有潜力通过优化工艺参数来加工具有致密微观结构和定制临床相关性能的牙科修复体。本研究探讨了氧化锆增强氟云母玻璃（FM）的SPS用于牙科修复材料的潜力。
通过熔体淬火技术获得FM玻璃料（44.5 SiO-16.7 AlO-9.5 KO-14.5 MgO-8.5 BO-6.3 F（重量%））。将玻璃料与20重量%的3摩尔%氧化钇稳定氧化锆（FMZ）进行球磨，以提高断裂韧性。混合物在50 MPa压力和100℃/分钟的加热速率下进行SPS烧结5分钟，温度从650℃升至750℃再升至850℃最后升至950℃。使用XRD进行相分析，并用SEM进行微观结构表征。评估了显微硬度、纳米压痕、孔隙率、密度、压痕断裂韧性和遗传毒性。
FMZ的SPS温度升高影响了其微观结构，导致孔隙率降低、密度提高以及机械性能优化，且对人牙龈成纤维细胞无遗传毒性。
