Radiofrequency heating and magnetic field interactions of fixed partial dentures during 3-tesla magnetic resonance imaging

摘要

Objective This study evaluated the heating and magnetic field interactions of fixed partial dentures in a 3-Tesla (3T) magnetic resonance imaging (MRI) environment. Study design Three substructure materials (Co-Cr, Ni-Cr, ZrO 2) were used to fabricate twelve 4-retained bridges and 12 crowns. Specimens were evaluated at 3T for radiofrequency heating and magnetic field interactions. One-way analysis of variance (ANOVA) test was used to compare continuous variables of temperature change. Significance was set at P .05. Translational attraction and torque values of specimens were also evaluated. Results None of the groups exhibited excessive heating (mean temperature change, 1.4 C), with maximum increase at the end of the T-1. Moreover, in all groups, only relatively minor magnetic field interactions that would not cause movement in situ were observed. Conclusion The study findings indicated that patients with fixed partial dentures (single crown or bridge) fabricated from Co-Cr, Ni-Cr, and zirconia substructures may safely undergo MRI at up to 3T.