Bessing C, Bergman M, Sjögren G
Department of Dental Materials and Technology, University of Umeå, Sweden.
Swed Dent J. 1991;15(1):7-14.
Previous studies have shown the clinical feasibility of using three alternatives to dental casting gold alloys Type 3. In the present study brazed specimens of these alternatives were evaluated using a corrosion test and a tensile test according to a proposed ISO Standard (ISO/DIS 9333). Brazed specimens of a high-gold alloy were used as a reference. Furthermore, the microstructure of the brazed joints and the fracture surface characteristics were monitored. The present study revealed that none of the specimens exhibited any visual sign of chemical attack after suspension in the test solution for 7 days. The tensile strength testing resulted in stresses at fracture point that met the requirements of the proposed ISO Standard. All fractures were of the ductile type. Cohesive failures were seen in all specimens except in the reference alloy (JS C) specimens. No clear relationship between fracture surface appearance and tensile strength was found. Distinct demarcation lines between brazing and parent materials were seen. Based on the present results there seems to be no reason to reject the use of brazed constructions made of the alternative alloys Midas, Rajah, and Albacast.
先前的研究已表明使用牙科铸造3型金合金的三种替代品的临床可行性。在本研究中，根据一项拟议的ISO标准（ISO/DIS 9333），使用腐蚀试验和拉伸试验对这些替代品的钎焊试样进行了评估。一种高金合金的钎焊试样用作参考。此外，还监测了钎焊接头的微观结构和断口表面特征。本研究表明，在测试溶液中悬浮7天后，没有一个试样出现任何化学侵蚀的视觉迹象。拉伸强度测试得出的断裂点应力符合拟议的ISO标准的要求。所有断裂均为韧性断裂类型。除了参考合金（JS C）试样外，在所有试样中均观察到内聚破坏。未发现断口表面外观与拉伸强度之间存在明显关系。在钎焊材料与母材之间可见明显的分界线。基于目前的结果，似乎没有理由拒绝使用由替代合金迈达斯、拉贾和阿尔巴卡斯特制成的钎焊结构。
