Department of Restorative Dental Sciences and Center for Dental Biomaterials, College of Dentistry, University of Florida, Gainesville, FL, USA.
J Dent Res. 2013 May;92(5):467-71. doi: 10.1177/0022034513484332. Epub 2013 Apr 8.
We tested the hypotheses that glass-ceramic veneers and overglazes degrade by ion exchange in an acidic environment, and that they degrade by breakdown of the silica network in a basic environment. Disk specimens of glass-ceramic veneer and glaze were fabricated and immersed in pH 2, 7, or 10 buffer solutions, for 1, 3, 5, 10, 15, and 30 days. Each specimen was placed in a shaker bath containing de-ionized distilled water at 80°C. Concentrations of Al(3+), Ca(2+), Zn(2+), Li(2+), and Si(4+) were analyzed by means of inductively coupled plasma atomic emission spectrometry (ICP/AES). Statistical analyses were performed by factorial ANOVA. Significant differences occurred among leached ion concentrations as a function of material type, solution pH, and exposure time. A substantial release of Si occurred at pH 10 over time, leading to a breakdown of the glass phase. At pH 2, dissolution was controlled by an ionic exchange mechanism. We conclude that ceramic veneers and glazes may be susceptible to considerable degradation in low- and high-pH buffer solutions.
玻璃陶瓷贴面和釉料在酸性环境中通过离子交换降解，在碱性环境中通过硅氧网络的分解而降解。我们制备了玻璃陶瓷贴面和釉料的圆盘试件，并将其浸泡在 pH 值为 2、7 或 10 的缓冲溶液中 1、3、5、10、15 和 30 天。每个试件都放在含有去离子蒸馏水的摇床浴中，温度为 80°C。采用电感耦合等离子体原子发射光谱法（ICP/AES）分析 Al(3+)、Ca(2+)、Zn(2+)、Li(2+)和 Si(4+)的浓度。通过方差分析进行统计分析。浸出离子浓度随材料类型、溶液 pH 和暴露时间的变化而存在显著差异。在 pH 值为 10 时，随着时间的推移，硅大量释放，导致玻璃相破裂。在 pH 值为 2 时，溶解受离子交换机制控制。我们的结论是，陶瓷贴面和釉料可能容易在低 pH 值和高 pH 值缓冲溶液中发生严重降解。
