Department of Gerodontology, University of Medical Sciences, Poznań, Poland Faculty of Commodity Science, The Poznań University of Economics, Poznań, Poland.
J Prosthodont. 2012 Feb;21(2):112-22. doi: 10.1111/j.1532-849X.2011.00808.x.
To study luminescence, reflectance, and color stability of dental composites and ceramics.
IPS e.max, IPS Classic, Gradia, and Sinfony materials were tested, both unpolished (as-cast) and polished specimens. Coffee, tea, red wine, and distilled water (control) were used as staining drinks. Disk-shaped specimens were soaked in the staining drinks for up to 5 days. Color was measured by a colorimeter. Fluorescence was recorded using a spectrofluorometer, in the front-face geometry. Time-resolved fluorescence spectra were recorded using a laser nanosecond spectrofluorometer.
The exposure of the examined dental materials to staining drinks caused changes in color of the composites and ceramics, with the polished specimens exhibiting significantly lower color changes as compared to unpolished specimens. Composites exhibited lower color stability as compared to ceramic materials. Water also caused perceptible color changes in most materials. The materials tested demonstrated significantly different initial luminescence intensities. Upon exposure to staining drinks, luminescence became weaker by up to 40%, dependent on the drink and the material. Time-resolved luminescence spectra exhibited some red shift of the emission band at longer times, with the lifetimes in the range of tens of nanoseconds.
Unpolished specimens with a more developed surface have lower color stability. Specimens stored in water develop some changes in their visual appearance. The presently proposed methods are effective in evaluating the luminescence of dental materials. Luminescence needs to be tested in addition to color, as the two characteristics are uncorrelated. It is important to further improve the color and luminescence stability of dental materials.
研究牙科复合材料和陶瓷的发光、反射和颜色稳定性。
测试了 IPS e.max、IPS Classic、Gradia 和 Sinfony 材料，包括未经抛光（原样）和抛光的样本。使用咖啡、茶、红酒和蒸馏水（对照）作为染色饮料。将圆盘状样本浸泡在染色饮料中长达 5 天。使用比色计测量颜色。使用荧光分光光度计在正面几何形状下记录荧光。使用纳秒激光荧光分光光度计记录时间分辨荧光光谱。
受检牙科材料暴露于染色饮料会导致复合材料和陶瓷的颜色发生变化，与未经抛光的样本相比，抛光样本的颜色变化明显较低。复合材料的颜色稳定性低于陶瓷材料。水也会使大多数材料的颜色发生明显变化。测试的材料表现出明显不同的初始发光强度。暴露于染色饮料后，发光强度降低了高达 40%，具体取决于饮料和材料。时间分辨荧光光谱在较长时间显示出发射带的一些红移，寿命在几十纳秒范围内。
表面更发达的未抛光样本具有较低的颜色稳定性。储存在水中的样本会在外观上发生一些变化。目前提出的方法可有效评估牙科材料的发光性能。除了颜色之外，还需要测试发光性能，因为这两个特性是不相关的。进一步提高牙科材料的颜色和发光稳定性非常重要。
