Methods: Test specimens of metal and non-metal restoration materials were fabricated and embedded with a reference specimen. The samples were placed in a 1.5-teslar MRI and CT (both Siemens, Germany) and evaluated in two dimensions. Artefact size and distortions were measured by using digital image analisis software.
Results: Out of 35 filling materials 6 materials showed no artefacts in CT. All metal based materials and 9 filling materials showed inhomogeneities in MRI. Artefacts which were caused by materials containing titanium and zirconia as well as filling materials consisting of rare earths showed erasements.
Conclusions: Metal based restoration materials had strong influence on CT, but they did not cause any artefacts in MRI images. Rare earths, such as Ytterbiumtrifluorid, as component of dental materials led to effacements in the MRI, but not in the CT. Developments of new dental materials should recognise these findings to reduce artefacts in MRI and CT images.