Duncan J D
J Prosthet Dent. 1982 Jan;47(1):63-8. doi: 10.1016/0022-3913(82)90244-x.
The casting accuracy of four nickel--chromium alloys (Ultratek, Omega, Microbond N/P2, and Nobil-Ceram) was compared to that of a precious alloy, Jelenko "O". The experiment consisted of fabricating and fitting cast copings to a cobalt--chromium test preparation of a maxillary central incisor and measuring the marginal discrepancy in eight selected points. The experiment indicated that Jelenko "O" had the greatest casting accuracy, followed successively by Ultratek, Nobil-Ceram, Microbond N/P2, and Omega. Statistical analysis of the data revealed no significant difference between Jelenko "O" and Ultratek alloys in fit of five of eight test points, but Jelenko "O" was significantly better in fit than Nobil-Ceram, Microbond N/P2, and Omega alloys. The following conclusions may be drawn from this experiment: 1. The nickel--chromium alloys tested did not cast as consistently or as accurately as precious alloy Jelenko "O". 2. The casting accuracy may be related to the amount of casting shrinkage that occurs in each alloy type, and further research is necessary to determine if expansion compensation of the selected phosphate-bonded investment recommended by the alloy manufacturers is adequate for the casting shrinkage of the test alloys. 3. Alloy composition and technique parameters may also influence the accuracy of the casting, but further research is necessary to determine their singular effects.
将四种镍铬合金（Ultratek、Omega、Microbond N/P2和Nobil-Ceram）的铸造精度与一种贵金属合金Jelenko "O "的铸造精度进行了比较。实验包括制作铸造桩核并将其适配到上颌中切牙的钴铬测试预备体上，并在八个选定的点测量边缘差异。实验表明，Jelenko "O "的铸造精度最高，其次依次是Ultratek、Nobil-Ceram、Microbond N/P2和Omega。对数据的统计分析显示，在八个测试点中的五个点的适配性上，Jelenko "O "合金和Ultratek合金之间没有显著差异，但Jelenko "O "在适配性上明显优于Nobil-Ceram、Microbond N/P2和Omega合金。从该实验中可以得出以下结论：1. 所测试的镍铬合金的铸造一致性和准确性不如贵金属合金Jelenko "O "。2. 铸造精度可能与每种合金类型中发生的铸造收缩量有关，需要进一步研究以确定合金制造商推荐的所选磷酸盐粘结包埋材料的膨胀补偿是否足以补偿测试合金的铸造收缩。3. 合金成分和技术参数也可能影响铸造精度，但需要进一步研究以确定它们各自的影响。
