Comparison of the artifacts on magnetic resonance imaging caused by different porcelain-fused-to-metals / 中国组织工程研究

ABSTRACT

BACKGROUND:The patients with porcelain-fused-to-metal crowns who do examination of magnetic resonance imaging (MRI) can cause artifacts. In recent years, researching for MRI artifacts of different porcelain-fused-to-metal materials has been some progress, but there are less quantitatively reports on the MRI artifacts of different porcelain-fused-to-metal materials. OBJECTIVE:To evaluate the artifact sizes shown on fast spin-echo T 2-weighted sequence caused by different kinds of porcelain-fused-to-metal crowns. METHODS:Forty-eight lower right first molar crown patients who had MRI examination in MRI room were enrol ed. The patients were divided into nickel-chromium al oy group, cobalt-chromium al oy group and titanium crown group. Al patients were examined with fast spin-echo T 2-weighted sequences by means of 1.5 T MRI apparatus. MRI artifacts areas of same sequence on the MRI images of different porcelain-fused-to-metal materials were analyzed with variance test. RESULTS AND CONCLUSION:Forty-five cases appearing to have high signal samples with clearly curved boundary zone that can be measured were selected, 15 cases for each material. Different artifact sizes were produced on the same sequence of different porcelain-fused-to-metal materials, which were (321.67±33.29) mm in the nickel-chromium al oy group, (263.53±34.95) mm2 in the cobalt-chromium al oy group, and (143.67±31.13) mm2 in the titanium crown group. There were significant differences between groups (P<0.05). The artifact size is smal est for the titanium crown and largest for the nickel-chromium al oy crown.