Porcelain veneers are a restoration method that applies bonding materials to fix thin porcelain restorations to the lip and buccal surfaces of the affected teeth without grinding or less grinding, in order to restore aesthetic defects, cover discoloration and other defects. It is easy to be accepted by patients because it has less tooth preparation than crown restorations, less stimulation to the pulp, stable color, aesthetics, good biocompatibility, wear resistance, and less staining and plaque adhesion. It is especially good for preserving the living pulp when restoring young permanent teeth and teeth with large pulp cavities. As a preservation of restorative treatment, porcelain veneers are now widely used in clinical aesthetic restoration, especially for the repair of fluorosis and anterior teeth affecting the aesthetic defects, defects. Porcelain veneers can be restored without tooth preparation, or less tooth preparation (often chosen), to maximize the preservation of dental tissue, pulp stimulation is small, in line with the biological principles of dental restoration. But even a small amount of tooth preparation, may also cause short-term postoperative sensitivity; and because of the small amount of tooth preparation, the restoration can not be made too thick, some morphological features are not easily expressed; its color shading ability is not as good as porcelain crown restorations. In order to obtain the perfect restoration effect, sometimes also need to be combined with other treatments. Such as: bleaching, gum, periodontal surgery, orthodontics, etc. According to the different production methods porcelain veneers are mainly divided into three categories. 1, traditional porcelain veneers (Feldspathic Porcelain Veneer); 2, cast porcelain veneers (IPS-Empress Porcelain Veneer); 3, CAD/CAM machined porcelain veneers compared with resin veneers. Resin veneers are a preservation aesthetic restoration method in which composite resin material is bonded directly or indirectly to the lip and buccal surfaces of the affected teeth. The advantages are no or less grinding of teeth, restoration of tooth surface morphology and basic color, shorter treatment, especially direct resin veneers can be completed in one visit, and the cost is relatively low. However, the strength of resin restorations is low, easy to wear, discoloration, aesthetic performance and durability is not as good as porcelain materials. The color effect of porcelain veneers after restoration is more beautiful; and not easy to change color, wear resistance, aesthetic effect lasting; can basically restore the strength of the original crown; no stimulation of the surrounding tissue, biocompatibility is good. However, porcelain veneers are indirect restorations, the process is long, the production process is complicated, the cost is higher. Porcelain veneer restoration indications include: 1, restoration of discolored teeth: such as fluorosis, light and moderate tetracycline teeth, old discolored teeth and light and moderate dead pulp discolored teeth. 2. Repair of mild to moderate enamel defects. 3. Restoration of anterior tooth gap. 4. Repair mild misalignment, ectopic and developmental malocclusion. 5.Repair anterior tooth defect.