Evaluation of corrosion degradation of amalgams by immersion and fracture test.
In this study an immersion and fracture test was used to evaluate the susceptibility of dental amalgams to degradation of their mechanical strength by corrosion. Specimens of each of the six types of high-copper amalgams and one type of low-copper amalgam were prepared and tested. Cylindrical specimens were grooved using a diamond cutoff blade and immersed in 1% NaCl to which H2O2 was added to increase the oxidation power. After two weeks of exposure the specimens and controls were fractured and the loss of strength was calculated. Two amalgams showed a significant loss of strength. The test procedure is relatively simple and does not require sophisticated electrochemical or analytical instrumentation. A higher resolution power might be achieved by increasing the severity of corrosion or the number of replicate tests.
Department of Dental Technology, Matsumoto Dental University 1780, Gobara, Hiro-oka Shiojiri Nagano 399-0781, Japan.
Noriko
N
Horasawa
Shigeo
S
Takahashi
Miroslav
M
Marek
D003343:Corrosion; D003723:Dental Amalgam; D003799:Dental Stress Analysis; D006861:Hydrogen Peroxide; D007101:Immersion; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D013314:Stress, Mechanical; D014867:Water
D014867:Water; D003723:Dental Amalgam; D006861:Hydrogen Peroxide