口腔不同金属材料全冠修复体CT成像伪影的实验研究

CT artifact caused by various types of dental crown in oral cavity

目的:对口腔常用的金属材料全冠在螺旋CT图像中的伪影进行实验研究,为临床口腔金属的选择提供参考依据。方法:用同一家猪头颅(六月龄,洛克白猪),模拟人的在体口腔环境,使用金钯、银钯、纯钛、钴铬、镍铬5种金属材料,在同一牙位制作5种金属冠,并分别戴入头颅的右下第1、2、3前磨牙,按照常规颌骨CT条件扫描(130ekv,1mm),测量伪影的尺寸、形态和面积。结果:5种金属冠都会产生以冠为中心向四周散射的伪影,金属的密度越高高亮度部分伪影面积越大,沿投照方向的长度越大,与原始截面图差异越大,差异具有统计学意义(P<0.05)。不同金属所产生的高亮度伪影和条索状伪影排列顺寻为纯钛<镍铬<钴铬<金钯<银钯,差异具有统计学意义(P<0.05)。结论:冠修复材料应首选密度较低的金属。

Objective： To compare various types of dental crown in CT images in order to provide evidence for choosing metallic dental crowns. Methods. Five kinds of metal materials widely used as dental prostheses including gold, silver, pure titanium, cobalt-chromium, nickel-chromium were used as dental crowns worn into the 1st, 2nd and 3rd right premolars in the cavity of the same pig （six months, Locke white pig）. Conventional jaw CT scans were applied （130 ekv, 1 mm） to measure the size, shape and vol- ume of crown artifacts. Results： All the five types of metal crowns produced scattering artifacts surround- ing the crown center, and the brightness, ing significant difference comparing with brightness and length of the artifacts, the cobalt-chromium 〈 gold 〈 silver （P 〈 0.05 ）crown repair material. length of the artifacts increased with the density of metals show- the original CT image （P%0.01）. According to the order of five metals can be listed as. pure titanium %nickel-chromium 05）. Oonclusion： metal of low density should be preferred for