There are many kinds of materials for dental crowns, generally the more commonly used in clinical practice are all-ceramic crowns, porcelain crowns, metal crowns, etc. The aesthetic effect of all-ceramic crowns is better. 1. The aesthetic effect of all-ceramic crowns is better, compared with natural teeth, there is a high degree of similarity from the chromaticity and appearance, with good aesthetic effect, such as polycrystalline ceramic crowns, zirconium dioxide all-ceramic crowns, with good strength, but relatively speaking, the price will be higher. 2. Porcelain crowns are made of metal on the inside and porcelain powder on the outside, which are sintered at high temperature. This material has the strength of metal crowns and all-ceramic crowns, but the long-term effect may be prone to chipping and so on, the service life of all-ceramic crowns will theoretically be shorter, in the MRI examination will have an impact. 3. Metal crowns are made through a special casting process, with ideal long-term effect and high strength, and the price is relatively cheap, but its aesthetics will be relatively poor.