When light strikes the surface of a veneered tooth it can penetrate on into the veneer's porcelain, just like it does with dental enamel. Once it has traversed the full thickness of the porcelain the light will reflect off the opaque cement and tooth dentin that lies underneath the veneer, and then on back out of the tooth. This translucency effect of the porcelain creates a lustrous appearance for the tooth that very closely resembles the appearance of enamel.
As a group, cosmetic dental bonding materials have the shortcoming of being susceptible to staining and discoloring. This is especially true when they are used in conjunction with individuals whose consumption habits include the use of tea, coffee, red wine, and tobacco products.
A significant advantage of placing porcelain veneers as opposed to cosmetic dental bonding is that a porcelain veneer's surface is just that, porcelain. Since porcelain is a ceramic, and therefore glass-like, a veneer's porcelain surface will be extremely stain resistant.
Veneers are routinely used to fix: