固定义齿修复材料对MRI图像的影响

The influence of dental casting alloys on MRI examination

目的分析不同口腔固定修复合金材料在MRI图像上产生伪影的大小。方法选择目前临床口腔固定修复最常用的贵金属和非贵金属作为实验材料,通过动物实验的方法对它们在MRI图像上产生伪影的大小作分析。结果不同的金属、同类金属不同的成分在MRI图像上产生的伪影大小不同;镍铬合金产生的伪影面积大,镍含量的差异可能对伪影范围的大小起主要作用;金合金对MRI图像几乎没有影响。结论镍铬合金对MRI有明显影响,金合金对MRI的影响小。

Objective To analyze the magnetic susceptibility difference artifacts caused by dental casting alloys used in domestic clinical prosthodontics. Methods Crowns made of five types of detental casting alloys were put on a crossbreed dog＇s first molar respectively. Then the dog＇s head was examined with a 0.1T MRI scanner. Efilm medical software was used to measure the artifacts. Results Metal artifacts around Ni - Cr alloy crowns were found on all the 3th alice of images with small differences in size. In the A group, the maximal artifact is about 28mm; in the B group, the maximal artifact is about 26mm; in the C group, the maximal artifact is about 24mm. Casting crowns made of gold alloy hardly create any artifacts. Conclusion Ni - Cr alloy creates obvious artifacts. While, gold alloy hardly create any artifacts. Gold alloy is relatively safe for MR image.