We used one metallic brace (nickel-titanium alloy) and three dental implants (100% titanium, 85% titanium-15% zirconium and 100% zirconia ceramic) embedded in a watermelon phantom. We imaged the phantom using 1.5 Tesla (Siemens) and 3.0 Tesla (GE) MRI, using T1, T2, DWI and GRE sequences (2mm thickness, 16 slices). We compared the artifacts created by all four metallic materials on 1.5 versus 3.0 tesla and T1 versus T2-weightwed sequences. We also applied variable bandwidths to identify the optimum protocol that acceptably reduces the artifact distortions.

We observed that the greatest MRI edge artifact is created by 100% titanium and the least MRI artifact by the 100% ceramic zirconia. Nickel-titanium and zirconium-titanium alloy had variable and minimal amount of artifact. Greater artifact was noted on 3.0 Tesla when compared to 1.5Tesla, particularly on GRE sequences (T2 worse than T1-weighted). Increasing the bandwidth alleviated the artifact, while reducing the signal-to-noise ratio, and the bandwidth of 250 seemed optimal.