Metal alloy porcelain teeth is still the mainstream of the Chinese market, experts: the current clinical use of porcelain dental materials in regular hospitals, are the regular products verified by the relevant state departments, the public need not worry too much. Recently, the Internet a “nickel-chromium porcelain teeth can cause kidney disease” post caused widespread concern, many have been inlaid with nickel-chromium porcelain teeth patients for this very panic, many people even go to the hospital to ask the doctor for its removal, however, dental experts believe that its adverse reactions are mainly oral allergies, there is no evidence that can lead to systemic organ damage . Experts said that the current clinical use of porcelain dental materials in regular hospitals, are the regular products verified by the relevant state departments, the public do not have to worry too much as long as they go to the regular medical institutions. Nickel-chromium alloy disadvantages: or can cause gum blackening “We have never received, or even never heard of the use of nickel-chromium alloy porcelain teeth in the industry, resulting in kidney disease and other systemic diseases of patients.” said Li Yan, director of the Department of Prosthodontics at the Affiliated Stomatological Hospital of Sun Yat-sen University. “Take the post online as an example, it is difficult to cite evidence that their kidney disease must have a causal relationship with porcelain dental materials, because people live and work in a complex environment, daily exposure to many triggers, improper lifestyle and diet, etc. may also affect the onset.” She showed that, worldwide, nickel-chromium alloy porcelain teeth have been decades of history, but also not heard that it will cause damage to various parts of the human body organs. Li Yan said, the international did not propose to ban nickel-chromium porcelain teeth, the public simply do not need to panic. ”But nickel-chromium alloy porcelain teeth do have shortcomings, the most common is to lead to gum blackening, allergies, inflammation of the oral cavity and other symptoms.” Li Yan introduced, nickel-chromium alloy material to do the porcelain teeth stability is not good enough, easy to oxidation, not resistant to corrosion. “In the oral saliva environment inside the long-term immersion, nickel ions are easy to precipitate, although its very safe, but individual patients will still have allergic reactions to nickel ions.” Li Yan introduced, for patients allergic to metal, it is recommended to use all-porcelain, plastic and other metal-free materials to do porcelain teeth. Metal alloy materials are still the main market Li Yan said that the current materials used in dentistry are no more than three categories: metal, ceramic and polymer materials and composite materials made of the three. Gold alloy: in the 18th century has been used in dentistry, is still the most ideal dental restorative materials. Its advantages are stable performance, not easy to oxidation; hardness is closer to the natural teeth, not easy to wear the jaw teeth, but the price is relatively high. It is now widely used in developed countries and regions. Silver amalgam: It has been used since the mid-19th century. The agencies involved have clear rules about the amount of mercury in it, and it is not approved if it exceeds the limit. “Although mercury can pollute the environment before it solidifies, there is no evidence that human health is endangered by the use of silver amalgam fillings. Therefore, silver amalgam remains one of the most important filling materials for posterior teeth to this day.” Li Yan said. Titanium alloy: Pure titanium has been used as the intraosseous implant part of dental implants because of its excellent biological properties. And titanium alloy has been used to make movable dentures and fixed dentures (titanium porcelain teeth), etc. due to its advantages of high strength, good toughness, light specific gravity, and not easy to oxidize in the oral cavity. However, due to the difficulty of processing and high investment in equipment, the price is on par with precious metal dentures. Nickel-chromium alloy: in our country is very market, the peak may occupy 80% of the porcelain dental field. Nickel-chromium alloy porcelain teeth are beautiful and inexpensive, it has the advantages of high strength, good combination with ceramic, cheap, etc., so it is widely used for fixed denture repair. Dental materials into the clinic must pass three hurdles Li Yan said, for the “kidney disease suspicion” incident, the public do not blindly gullible. “In fact, dental instruments and materials are biological materials, to enter the clinic must go through three hurdles, one is the primary screening test to confirm that the material is not cytotoxic and genotoxic; the second is the secondary test, the material and its extract by oral or intravenous injection in animals to confirm that it is not systemic toxicity, no irritation, no allergies, etc.; third is the pre-clinical application test, that is Materials made into finished products for the corresponding parts of the animal, such as dental materials should not be pulp, oral mucosa irritation, etc.; material testing is conducted in the national designated institutions, according to the International Organization for Standardization certification before entering the clinical application.” She believes that the porcelain dental materials currently used clinically in regular hospitals are regular products that have been verified by the relevant state departments. ”At present, most of China’s dental materials rely on imports, only a few auxiliary materials produced by domestic manufacturers or Sino-foreign joint venture manufacturers, so the cost is higher, but because the domestic consumption level is relatively low, the fee has been considered cheap. Many people from outside China are happy to have their teeth veneered in China.” She said.