Dental veneers operate on a simple premise: make teeth appear perfect by placing a thin material onto them. In other words, they are a cosmetic change for something that is otherwise impossible, difficult, or more costly to change by other means.
Dental veneers are usually made of porcelain, but can also be made of a composite resin. They are very thin, only about 1 millimeter thick, and are made to look like natural, healthy teeth. While one millimeter is not thick by comparison to just about anything, they do add thickness to the teeth they are placed on. To counteract this added thickness and to make them even less noticeable, the enamel on the front of the teeth is removed by just less than that amount. This process prevents changes to the patients bite.
A tooth receiving a dental veneer, which can be placed on one tooth or many, has a mold made of it after the removal of the enamel. The veneer is then made in a factory to fit that tooth precisely and is cemented onto it using a special dental adhesive. By this means, the natural tooth is covered up and the tooth will appear new and perfect for years to come.