不同材料烤瓷冠与金属冠磁共振成像伪影的比较

Comparison of artifacts on magnetic resonance imaging caused by different porcelain-fused-to-metal crowns and metal crowns

目的分析不同材料烤瓷冠和铸造冠在磁共振成像(MRI)图像上产生伪影的大小。方法在临床随机选取的右侧上颌第二磨牙模型制作钴铬烤瓷冠、钴铬金属冠、镍铬烤瓷冠、镍铬金属冠各一个,并以丙烯酸树脂冠作为对照,采用1.5 T MRI扫描仪对5个牙冠进行扫描,观察不同材料牙冠成像伪影的大小。结果同一序列中不同材料试件所产生伪影面积的差异均有统计学意义,不同材料试件两两比较,其差异也有统计学意义。钴铬金属冠产生的伪影面积最大,镍铬烤瓷冠产生的伪影面积最小。结论 4种牙冠对MRI的影响不同,口腔金属修复体产生的伪影与材料类型密切相关。

Objective This study aimed to investigate the artifacts of different porcelain-fused-to-metal crowns and metal crowns on magnetic resonance imaging（MRI）. Methods One Co-Cr porcelain crown, one Co-Cr metal crown, one Ni-Cr porcelain crown, and one Ni-Cr metal crown were placed in a cylindrical plastic vessel filled with distilled water. An arcrylic resin crown was used as control and then scanned using roution head sequence, including FRFSET2WI, GRET2＊WI, and T1FLAIR, on a 1.5 T scanner. The MRI artifact areasof different porcelain-fused-to-metal crowns and metal crowns were calculated and analyzed with variance test. Results ANOVA of factorial design indicated significant differences among the crowns. Co-Cr metal crown produced the largest artifact, whereas Ni-Cr porcelain crown produced the least. Conclusion Various crowns differently affected MRI images. The artifacts produced by the crownswere closely related to the type of material.