J Korean Radiol Soc.
1992 Jun;28(3):463-469.
Artifacts by dental materials on magnetic resonance imaging
Abstract
- Magnetic resonance imaging(MRI)has proved to be a valuable method for evaluation of the head and neck. Unfortunately, metallic devices associated with certain dental fillings and applicances often cause variable artifacts that can obscure normal or pathologic conditions on MR and computed tomography. In this work, we assessed the MR appearance of dental prosthetic materials in vitro and in vivo including precious alloys. Nonprecions alloys, resin, amalgam and titanium alloy, For in vivo studies, these materials were placed in healthy volunteer's mouths and then images were assesed. Analyis of the appearance of shape and extent of artifact,and observed influence of these artifacts on the image interpretation at 0.2 Tesla permanent type MR scanner were valuated. Material used as temporary or permanent filling of crowns such as amalgam. precious alloy and, microfilled resin did not cause artifact on the image. The size of the artifact produced by the nonprecious alloys was influenced by the ferromagnetism of the object and the volume prosthesis, and was related to the scanning sequence. Nonprecious alloys produced minimal local signal distortions, where precious alloys, and dental resin had no effect on the MR image in vivo. These results were mainly from a low field strength MR scanner used in this study.
