Wictorin L, Fredriksson H
Odontol Revy. 1976;27(3):187-96.
The composition and structure were studied in the cast and in the solder of bridges which had failed clinically. Both materials were gold alloys but with different contents of Pt, Ag and Zn. The metallographic investigation revealed defects mostly in the solder, situated in the subsurface layer. SEM studied of the fracture surface revealed large porosites and a structure of dense parallel lines--striations--, indicating that the material had failed from fatigue. The materials in the fractured bridges were identified by micro-probe measurements. It was stated that cast material and solder material used together, were of different composition.
对临床上已失效的桥体铸件及焊料的成分和结构进行了研究。两种材料均为金合金，但铂、银和锌的含量不同。金相研究发现缺陷大多位于焊料中，处于次表层。对断口表面的扫描电子显微镜研究显示有大量气孔以及致密平行线结构——条纹，表明材料因疲劳而失效。通过微探针测量确定了断裂桥体中的材料。结果表明，一起使用的铸造材料和焊料材料成分不同。
