Xinhua Beijing, March 22 (Xinhua Cui Jing, Zhou Tingyu) “lightly lead to hives, serious endanger kidney function ……” recently, an online “nickel-chromium porcelain teeth can cause kidney disease ” post caused widespread public concern. Different expert opinions and media interpretations, a time to countless people equipped with nickel-chromium porcelain teeth doubts. Can nickel-chromium porcelain teeth cause kidney disease? Is it necessary for patients who have been fitted with Ni-Cr porcelain teeth to have them removed? Should the use of less expensive Ni-Cr porcelain teeth be banned in China? How to prevent the risk of porcelain dental inlays …… Xinhua News Agency reporter recently interviewed authoritative experts in the field of dentistry, for the public to crack the “nickel-chromium porcelain teeth cause disease” caused by the four major unanswered questions. Suspicion one: nickel-chromium porcelain teeth can cause kidney disease? Recently, a “nickel-chromium porcelain teeth can cause kidney disease” post circulated in major websites and attracted numerous follow-up posts, posters said they installed two nickel-chromium porcelain teeth, coughing for six months, allergic purpura, hives, laryngitis and other symptoms not previously, and urine test heavy metals seriously exceeded the standard, was preliminarily diagnosed with occult nephritis, and provided numerous papers on the existence of a causal relationship between nickel-chromium porcelain teeth and kidney disease. ”We are very concerned about this incident, and in any case, the occurrence of this incident is a good thing for the restorative dentistry industry, which shows that patients’ awareness of oral hygiene has increased and helps to promote oral health care services in the country.” As the director of the Chinese Society of Stomatology Restorative Committee, Feng Hailan, director of the Department of Prosthodontics at Peking University School of Stomatology, said this when talking about the “nickel-chromium porcelain tooth fiasco. In order to obtain a broader sample, Feng Hailan recently conducted an emergency survey of the West China Dental Hospital of Sichuan University, the Fourth Military Medical University Stomatology Hospital and other eight dental hospitals in the country with a greater impact on the use of nickel-chromium porcelain teeth. ”Preliminary statistics show that since the introduction of nickel-chromium porcelain teeth in China at the end of the 1970s, the above eight units have made a total of about 900,000 units of nickel-chromium alloy porcelain crowns, of which only five cases may cause allergic reactions, in addition to not seeing the cases that lead to kidney disease.” Feng Hailan said. Feng Hailan pointed out that the medical does not exclude that nickel-chromium alloy has a certain degree of allergenicity, but wearing nickel-chromium porcelain teeth in cases of allergic reactions are rare, while the causal relationship between nickel-chromium porcelain teeth and kidney damage is not yet confirmed by evidence. She suggested that patients who are worried about their kidney disease due to the installation of nickel-chromium porcelain teeth can go to a medical institution for a comprehensive and detailed examination, and ask experts in nephrology, toxicology, internal medicine, nutrition, occupational diseases and other aspects of consultation, so as to draw scientific conclusions about their condition. Suspicion two: has been installed nickel-chromium porcelain teeth patients have no need to remove? Nickel-chromium porcelain dental fiasco, many people have run to the oral hospital to request the removal of the original set of nickel-chromium porcelain teeth, in recent days, Beida Dental Hospital almost every day to receive such patients. In this regard, Feng Hailan said, the current study shows that nickel-chromium alloy is still a safe dental materials, patients do not need to panic, do not blindly remove, so as not to cause physical injury and economic loss. If the body has abnormal symptoms, they should go to the hospital to determine the final cause of the disease before making a decision. ”Patients who are allergic to nickel-chromium porcelain teeth will react within a relatively short period of time after the veneer, mainly symptoms such as skin allergy and perioral inflammation; if there are no such symptoms for several years, there will be no further risk of sensitization.” Feng Hailan said that patients can also go to the allergic reaction department set up by some hospitals for nickel allergy testing to determine whether they are suitable for installing nickel-chromium porcelain teeth if they think they need it. Zhao Xinyi, director of the Oral Materials Committee of the Chinese Dental Association, pointed out that for the vast majority of patients using nickel-chromium porcelain teeth, nickel-chromium alloy has good biosafety, only for a very small number of patients will have some side effects, the main cause of side effects is the release of nickel ions from nickel-chromium alloy. Zhao Xinyi said, most of the nickel released from nickel-chromium porcelain teeth will be swallowed into the digestive tract, will not be gathered in the mouth, and the amount of nickel released from nickel-chromium alloy is significantly lower than the amount of nickel ingested in people’s diet, despite this, a small amount of nickel will still be absorbed by the body, patients wearing nickel-chromium porcelain teeth for a certain period of time, although the nickel content in blood, saliva, urine will increase, but generally within the safe range, will not produce harm. ”In fact, a large number of supplies in our real life, such as pots and pans contain nickel, medical devices also contain nickel, nickel is an essential element for the human body, has many beneficial effects on human health.” Xu Jun, deputy director of the Department of Prosthodontics at Peking University School of Stomatology, said. The World Health Organization states that a rough estimate of a person’s daily intake of nickel is 100 to 600 micrograms. Under normal conditions the adult human body contains about 10 milligrams of nickel. Zheng Gang, director of the Oral Materials Research Department at Peking University School of Stomatology, said that nickel can be excreted through metabolism, fearing that they are suffering from kidney disease due to the installation of nickel-chromium porcelain teeth netizens in the urine test, the detected nickel content exceeds the normal value of 10 times proves this point, but where these nickel is from is not certain. Suspicion three: whether the use of nickel-chromium porcelain teeth should be banned in the country? After the “nickel-chromium porcelain teeth caused by disease” fiasco, some media reports that nickel-chromium alloy has been banned in Western countries, proposed that China should also ban the use of such products, and by precious metal porcelain teeth will replace it. In this regard, Zhao Xinyi pointed out that the media reported that the West banned nickel-chromium alloy is not the fact that some Western countries are still using this material in the field of dentistry, such as Japan’s national standards in 2005 will still be included in the clinically available alloy materials, and included in the national insurance program, paid for by insurance companies; the U.S. Food and Drug Administration in 2004 issued a management document on nickel-chromium alloy. also listed nickel-chromium alloy as a clinically available dental alloy and did not ban it. Why not ban nickel-containing alloys when it is clear that nickel is allergenic? Zheng Gang said, this is mainly for the following reasons: First, very few people are allergic to nickel, and are generally allergic to skin contact, such as allergy to the watch chain, necklace, etc., caused by contact with the oral cavity allergy is very rare; Second, nickel-chromium alloy has good mechanical properties and corrosion resistance, used in oral prosthetic system has very good performance, in these areas, in addition to precious metals, it can be said that nickel-chromium alloy is the best choice; third, the price is cheap, which can make more people get more satisfactory dental restoration. ”Should prevent some one-sided conclusions mislead patients to choose all precious metal porcelain teeth, which does not meet our national conditions, but also does not meet the consumption level of our people.” Wang Xing, president of the Chinese Society of Stomatology, said. Wang Xing said that the current domestic market application of porcelain teeth mainly include all-porcelain teeth, precious metal porcelain teeth, nickel-chromium porcelain teeth, etc., and nickel-chromium porcelain teeth occupy almost 80% of the market. At present, the price of precious metal porcelain teeth is more than two times that of nickel-chromium porcelain teeth, while all-porcelain teeth are three to four times that of nickel-chromium porcelain teeth. ”Patients should choose the right product according to their financial ability and requirements for aesthetics, if they completely abandon the nickel-chromium porcelain teeth, the final benefit is the manufacturers and distributors of medical equipment, hospitals and doctors will also benefit, the only damaged people.” Wang Xing said. He pointed out that materials containing nickel have been used in the oral cavity for nearly 100 years, and nickel-chromium alloy for porcelain dental production also has a history of more than 30 years, and these materials are not only used for porcelain dental restoration, there are many applications in oral treatment, is a more mature oral restorative materials. Feng Hailan said, due to the better biocompatibility of precious metal porcelain teeth, may lead to fewer adverse reactions, with the improvement of people’s living standards, the Western countries choose precious metal porcelain teeth more and more patients, which also appeared in the same trend in the country. At present, the number of nickel-chromium porcelain teeth installed in the North University Dental Hospital has been reduced from the former 100% to less than 30% now. Suspicion four: how to prevent the risk of porcelain dental inlay? Many experts argue that the nickel-chromium alloy oral materials are safe for the human body, but Wang Xing also stressed that the safety of nickel-chromium porcelain teeth have a prerequisite, that is, the use of qualified nickel-chromium alloy materials, processing and production specifications meet the standards, this principle also applies to other oral materials. The reporter learned that there are some irregular manufacturers in the domestic market in order to save costs and production does not meet the quality requirements of porcelain teeth, or some irregular medical institutions ordered the use of quality porcelain teeth, for patients inlaid porcelain teeth bring risks. In this regard, Wang Xing pointed out that to ensure the safety of porcelain teeth and other oral materials, medical institutions must be in accordance with the relevant provisions of the use of formal enterprises qualified products, purchase products must check the enterprise’s product registration certificate, production license and business license, or can not be imported. At the same time medical institutions to strictly comply with the clinical guidelines and operating norms of porcelain dental restoration, before the oral restoration to ask the patient’s allergy history, to inform the risk of allergy to the product. Feng Hailan reminded that patients should choose regular medical institutions, not to be greedy for cheap and accept the treatment of some unqualified individuals or institutions. “If the installation of a nickel-chromium alloy porcelain crown as long as 50 yuan, without identification is fake. This money is not even enough to buy a block of raw materials, it is unknown what materials are used.” In addition, many experts also stressed that the relevant regulatory authorities should strengthen the supervision of medical device manufacturers, medical institutions, regulate the oral health care market, to ensure that the products used in clinical compliance with quality standards and safety norms for dental treatment.