Effect of Magnetic Resonance Applications on Dental Amalgam Phase Changes

Aim: The aim of this study was to examine the potential for low- versus high-field strength magnetic resonance applications to effect phase changes in high-copper dental amalgam as detected by X-ray diffraction (XRD) analysis. Materials and Methods: Disk-shaped samples (5 x 1 mm2) of amalgam filling were prepared (n = 90) and were thermocycled for 1000 cycles. The samples were then divided into three groups that were exposed to a 0.2 tesla or a 1.5 tesla magnetic field, or received no magnetic field exposure as a control. The samples were subsequently examined by XRD for phase determination 1, 7, and 30 days later. Results: The relationships between the gama, gama1, and eta phases, as well as the mercury peak intensities, were statistically analyzed using analysis of variance and the Kruskal Wallis test. No statistically significant differences were observed (p > 0.05). There were also no significant time-dependent differences observed between the gama, gama1, and eta phases, or in the mercury peak intensities, of the groups, according to the Friedman test (p > 0.05). Conclusion: The results of this study indicate that exposure to a magnetic field via magnetic resonance imaging does not affect the structure of dental amalgam.