If your teeth are badly stained, shaped or crooked – your smile may benefit from having veneers placed onto the surface of the affected teeth. Veneers are simply thin pieces of porcelain that are cemented over the front of your teeth in order to change their color or shape. Porcelain veneers are primarily used on teeth with uneven surfaces or that are chipped, discolored, oddly shaped, unevenly spaced or crooked.