Castilho Júlio Cezar de Melo, Takeshita Wilton Mitsunari, dos Santos Luis Roque de Araújo, de Moraes Luiz César, Medici Filho Edmundo, de Moraes Mari Eli Leonelli
Discipline of Radiology, Department of Surgery, Periodontology and Radiology, São Paulo State University, São José dos Campos, Dental School, Brazil.
J Appl Oral Sci. 2006 Jan;14(1):16-20. doi: 10.1590/s1678-77572006000100004.
The purpose of this article was to compare the mean value of optical density of four porcelains commonly used for fabrication of inlay/onlay prostheses using direct digital radiograph. The sample consisted of 20 2-mm thick porcelain specimens (measured by digital pachymeter): Empress (Ivoclair), Simbios (Degussa), Vita Omega 900 and Vitadur Alpha (Vita Zahnfabrik). The values of optical density of the specimens were expressed in millimeters aluminum equivalent (mm eq Al). The samples were X-rayed using two charge coupled devices (CCD) - RVG (Trophy) - Visualix (Gendex) and a phosphor plate system - Digora (Soredex). The optical density reading was performed with Image Tool 1.28 in a total of 110 measurements. Statistical analysis showed that there were statistically significant differences in all materials studied (p < 0.05) regardless of the radiographic system used. The highest optical density value was found for Omega 900 (1.8988 mmeqAl - Visualix - Gendex) and the lowest for Vitadur Alpha (0.8647 - Visualix - Gendex). Thus, the material presenting the highest degree of optical density was Omega 900, Empress and Simbios presented intermediate optical density values, Vitadur Alpha presented the lowest value, and the optical density of porcelains was not influenced by the digital radiography systems.
本文旨在使用直接数字化射线照相法比较常用于制作嵌体/高嵌体修复体的四种瓷材料的光密度平均值。样本包括20个2毫米厚的瓷标本（用数字测厚仪测量）：铸瓷（义获嘉）、西姆斯（德固萨）、维他欧米茄900和维他杜尔阿尔法（维他齿科）。标本的光密度值以铝当量毫米（mm eq Al）表示。样本使用两个电荷耦合器件（CCD）——RVG（ Trophy）——Visualix（登士柏）和一个磷光板系统——Digora（索雷克斯）进行X射线照射。总共进行了110次测量，使用Image Tool 1.28进行光密度读数。统计分析表明，无论使用何种射线照相系统，所有研究材料之间均存在统计学上的显著差异（p < 0.05）。欧米茄900的光密度值最高（1.8988 mmeqAl——Visualix——登士柏），维他杜尔阿尔法的光密度值最低（0.8647——Visualix——登士柏）。因此，光密度最高的材料是欧米茄900，铸瓷和西姆斯呈现中等光密度值，维他杜尔阿尔法呈现最低值，并且瓷材料的光密度不受数字射线照相系统的影响。
