Dental veneers are thin, custom-made shells that are bonded to the front surface of teeth to improve their appearance. These shells change the color, shape, size, and/or length of the teeth. Dental veneers can be made from porcelain or from resin composite materials. Each has advantages: Porcelain veneers resist stains better and better mimics the light-reflecting properties of natural teeth. Resin veneers are thinner and require removal of less of the tooth.