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近20年来国外已在合金配方上突破铜含量不得>6%的限制,提高到30%左右,形成一高铜合金体系。美国牙医协会(ADA)已于1977年对检验银汞合金的1号标准作了相应修订,给予正式认可。目前国外高铜合金已逐步取代低铜合金,1983年美国已有2/3病人应用高铜合金,某些牙体修复学教科书亦已提出应以高铜合金为唯一合用材料。而我国仍在使用性能较差的普通型屑型低铜合金,相当国外50年代水平,存在差距较大。有必要对其发展动态有一概括性了解,以适应知识更新的需要。
Over the past 20 years, foreign countries have exceeded the copper content in the alloy formula shall not exceed 6% limit, increased to 30%, forming a high copper alloy system. The American Dental Association (ADA) has formally approved the No.1 standard for testing amalgam in 1977. At present, foreign high-copper alloys have gradually replaced low-copper alloys. In 1983, two-thirds of the patients in the United States had used high-copper alloys. Some textbooks for dental restorations have also proposed that high-copper alloys be the only materials of common use. While our country is still using the poor performance of ordinary low-alloy copper filings, quite the level of foreign 50's, there is a big gap. It is necessary to have a general understanding of its development in order to adapt to the needs of knowledge updating.