Department of Fixed Prosthodontics, Osaka University Graduate School of Dentistry, Osaka, Japan.
Dent Mater J. 2011;30(3):330-5. doi: 10.4012/dmj.2010-142. Epub 2011 May 20.
Yttria-based zirconia material (Y-TZP) widely used in dentistry, may degrade in a humid, low-temperature environment such as that in the oral cavity. The aim of this study was to compare the degradation of a new silica doped Y-TZP material with that of conventional Y-TZP by using accelerated aging tests at 200°C. The results of the accelerated tests revealed that after 50 hours of aging, the conventional Y-TZP samples had damaged surfaces that were weakened by 50 to 60%, while the silica-doped Y-TZP samples were only weakened by less than 20%. The monoclinic content of the conventional Y-TZP samples increased substantially to 62.7%, however, that of silica-doped Y-TZP samples was 18.9% after 5 hours of aging. It was concluded that a new type of silica-doped Y-TZP, created by adding a small amount of silica to Y-TZP, will be more resistant to low temperature degradation than conventional Y-TZP.
氧化钇稳定氧化锆材料（Y-TZP）在牙科中广泛应用，但可能会在口腔等潮湿、低温环境中降解。本研究旨在通过在 200°C 下进行加速老化试验，比较新型掺硅 Y-TZP 材料与传统 Y-TZP 的降解情况。加速试验结果表明，经过 50 小时老化后，传统 Y-TZP 样品表面受损，强度降低了 50%至 60%，而掺硅 Y-TZP 样品的强度仅降低了不到 20%。传统 Y-TZP 样品的单斜相含量显著增加到 62.7%，而掺硅 Y-TZP 样品在 5 小时老化后仅为 18.9%。结论认为，通过在 Y-TZP 中添加少量硅制成的新型掺硅 Y-TZP 比传统 Y-TZP 更能抵抗低温降解。
