Table 2. Frequency of the changes of the discs of dental amalgam subjected to high temperatures.
| Characteristics |
Contour® Kerr® |
Admix® SDI® |
Nu Alloy® Newstethic® |
|---|---|---|---|
| 200şC | |||
| Color | Bright gray color remains (100%) | Bright gray color remains (100%) | Bright gray color remains (100%) |
| Texture | The surface appearance is porous (100%) | The surface appearance is porous (100%) Superficial nodules appear (100%) | The surface appearance is rough and porous (100%) |
| Fissures and cracks | Are not presented (None) | Are not presented | Are not presented |
| Fracture | It’s not presented (None) | It’s not presented | It’s not presented |
| Dimensional stability | It’s not observed | It’s not observed | It’s not observed |
| Fragmentation | It’s not observed | It’s not observed | It’s not observed |
| 400şC | |||
| Color | Gray color remains but not as bright (100%) | Gray color remains but not as bright (100%) | Gray color remains but not as bright (100%) |
| Texture | The surface appearance is porous (100%) Superficial nodules appear (100%) | The surface appearance is compact (100%) Superficial nodules appear (100%) | The surface appearance is porous (100%) Superficial nodules appear (100%) |
| Fissures and cracks | Pores and cracks are observed on the nodules (100%) | Pores and cracks are observed on the nodules (100%) | Pores and cracks are observed on the nodules (100%) |
| Fracture | It’s not presented | It’s not presented | It’s not presented |
| Dimensional stability | It’s not observed | It’s not observed | It’s not observed |
| Fragmentation | It’s not observed | It’s not observed | It’s not observed |
| 600şC | |||
| Color | Changes to a dark opaque gray (100%) | Changes to a dark opaque gray (100%) | Changes to a dark opaque gray (100%) |
| Texture | The surface appearance is compact (100%) and the nodules disappear (100%) | The surface appearance is compact (100%) and there’s traces of nodules (100%) | The surface appearance is compact (100%) and the nodules disappear (100%) |
| Fissures and cracks | There are fissures and cracks where the nodules were (100%) | There are fissures and cracks where the nodules were (100%) | There are fissures and cracks where the nodules were (100%) |
| Fracture | Deep fracture lines are observed (66.6%) | It’s not presented | Deep fracture lines are observed (33.3%) |
| Dimensional stability | Thermic expansion is observed –shape alteration– (100%) | Thermic expansion is observed –shape alteration– (66.6%) | Thermic expansion is observed –shape alteration– (33.3%) |
| Fragmentation | It’s not observed | It’s not observed | It’s not observed |
| 800şC and 1.000şC | |||
| Color | Changes to black opaque with bright gray spheres (100%) | Changes to black opaque with bright gray spheres (100%) | Changes to black opaque with bright gray spheres (100%) |
| Texture | A pulverized phase and a compact phase shaped like little spheres are observed | A pulverized phase and a compact phase shaped like little spheres and bands are observed | A pulverized phase and a compact phase shaped like little spheres are observed |
| Fissures and cracks | Fragmentation and pulverization are observed (100%) | Fragmentation and pulverization are observed (100%) | Fragmentation and pulverization are observed (100%) |
| Fracture | Fragmentation is observed (100%) | Fragmentation is observed (100%) | Fragmentation is observed (100%) |
| Dimensional stability | Fragmentation and pulverization by thermic expansion are observed–shape alteration– (100%) | Fragmentation and pulverization by thermic expansion are observed –shape alteration– (100%) | Fragmentation and pulverization by thermic expansion are observed–shape alteration– (100%) |
| Fragmentation | Fragmentation and destruction of the disc is observed (100%) | Fragmentation and destruction of the disc is observed (100%) | Fragmentation and destruction of the disc is observed (100%) |