Background : Porcelain restorations have double-layer color effects resulting from the presence of translucent and opaque layers . Enough thickness of translucent dentin porcelain was needed to imitate the optical property of natural teeth .

实验背景：陶瓷修复体的颜色是由 不透明瓷层/透明体瓷层的双层颜色效果决定的，要使金属烤瓷修复体能和天然 牙齿的颜色相匹配，需要一定的瓷层厚度。