Development of Computerized Automatic EPMA System for the Evaluation of Dental Metals

在最终的临床试验之前，正在对牙科金属进行各种基本的评估试验，包括生物和化学因素，这些因素在其他标准中尤为重要。自1985年以来，我们一直在研究中使用EPMA观察和分析用于浸泡试验或皮下植入试验的金属，以及从口腔环境中取出的牙釉质，以研究其表面状态或组成元素数量的变化。因此，通过基本的评估测试或长期的口腔内使用，牙科金属的细微变化的基本概念变得清晰。下一步是定期评估由不同标准化合金制造的口内牙弓的变化。为了进行比较，在试验前后在同一地点对试样进行观察和分析，因此，分析区域的准确再现是必不可少的。此外，由于样本数量的增加，需要更有效的分析。由于原EPMA系统不能满足我们的要求，本项目开发了自动定量分析系统，以提高观察和分析的准确性和效率。这是一种利用坐标存储器使计算机存储大量分析区域的系统。它连接到已经编程用于自动分析的载物台控制单元。此外，由于光电编码器、直流电机的开发以及齿轮传动过程中消除齿隙的程序的开发，大大提高了分析精度。因此，即使在高放大率（>5000X）下，从存储的坐标中回忆分析区域也显示出良好的再现性，并且实现了高得多的分析效率。（摘自第55届口腔学会年会）

Preceding the final clinical test, various basic evaluation tests are being performed on dental metals regarding biological and chemical factors which are especially important among the other criteria. Since 1985, observation and analysis by EPMA have been performed in our research, on the metals used in immersion tests or subcutaneous implant tests, and restorations removed from oral environment, to study the changes in their surface condition or quantity of the constituent elements. As a result, basic idea of the fine changes in dental metals which have gone through basic evaluation tests or long terms of intra-oral usage, is becoming clear. The next step was to periodically evaluate the changes in the intra-oral restorations fabricated by different standardized alloys. Observation and analysis of the specimen is performed at the same site before and after the tests for comparison, and thus, accurate reproduction of the analyzing area is essential. Furthermore, due to increase in number of the specimen, much efficient analysis was being required. Since the former EPMA system did not meet our expectations, automatic quantitative analysis system was developed in this project to improve the accuracy and efficiency for observation and analysis. This is a system which enables the computer to memorize a large number of analyzing areas by coordinate memory device. It is connected to the stage control unit which already has been programmed for automatic analysis. Moreover, analyzing accuracy was much improved by the development of light sensed encoder, direct current motor, and the program that eliminates backlash during its gear operation. Consequently, even under high magnification (>5000X), it showed an excellent reproduction in recalling the analysis area from the memorized coordinates, and much higher analysis efficiency was achieved. (Reported in the 55th Stomatological Society Annual Meeting)