NATURE OF ALLOY SYSTEMS FOR CROWN AND BRIDGE RESTORATION

本研究的格式研究目标涉及概念和 新材料的配制，或现有材料的修改 材料，以提高冠桥修复体的质量 无论是在陶瓷金属装饰以及那些制成的完整的铸造 片. 从广义上讲，这一建议包括：1）研究自然 陶瓷-金属（P/M）界面，识别化合物的类型，如果 以及它们对粉末冶金结合强度的影响。 在此阶段，离子镀 技术，这是一个相对较新的技术将被使用; 2）研究磨损的 各种合金系统以及它们磨损其他 修复材料。 这将通过使用完整的 义齿患者和使用特殊设计的可拆卸义齿 臼齿插入物。 插入件将通过以下方式被移除、安装和数字化 一个特制的测针，用来收集X光片表面的读数， y轴和z轴。 计算机将接收这些数据，并绘制出 曲面的拓扑学 3)研究在体内和体外的程度， 新开发的合金的失泽，并将结果与一些 由一些市售合金获得。 在体内部分 在这项研究中，将使用全口义齿患者， 对9种合金的失泽程度进行了测定; 4）研究 铸造合金的凝固模式和熔融合金的流动模式， 受到各种操纵条件的影响。 本研究将 通过改造铸造机的手臂来完成; 5）研究 在铸造温度下的变形以及变形是如何 受到铸造合金收缩力的影响。 这项工作将在 通过相对于由高熔点合金制成的参考棒进行铸造。 6)可能 修改或改变牙科投资的组成， 生产更精确的铸件。

The format research objectives of this study involve the conception and formulation of new materials, or modifications of already existing materials, in order to improve the quality of crown and bridge prostheses both in porcelain-metal restorations as well as those made of complete cast pieces. In a broad concept this proposal involves: 1) Studying the nature of porcelain-metal (P/M) interface, identifying the type of compounds, if any, and their effect on P/M bond strength. In this phase, ion plating technic which is a relatively new technic will be used; 2) Studying wear of various alloy systems as well as the degree that they abrade other restorative materials. This will be accomplished by employing complete denture patients and utilizing specially designed dentures with detachable molar inserts. The inserts will be removed, mounted and digitized by means of a specially made stylis, to collect readings of the surfaces on the x, y, and z axes. A computer will receive these data and will plot the topology of surfaces. 3) Studying in-vivo and in-vitro the degree of tarnish of newly developed alloys and comparing the results to some those obtained from some commercially available alloys. In the in-vivo portion of the study, complete denture patients will be utilized and in each patient the degree of tarnish of 9 alloys will be determined; 4) Studying solidification patterns of cast alloys and flow patterns of molten alloy as influenced by various manipulative conditions. This study will be accomplished by modifying the arm of a casting machine; 5) Studying deformation of investments at casting temperature and how deformation is affected by the shrinkage force of cast alloys. This will be carried out by casting against reference rods made of high melting alloy. 6) Possible modification or alteration of the composition of dental investments to produce more accurate castings.