离体牙体外实验法对螺旋CT三维重建准确性的评价

目的:应用离体牙体外实验的方法对螺旋CT三维重建测量结果的准确性进行分析比较。方法:对20颗离体牙标本的实验动物模型进行CT扫描和三维重建,并测量标记物边长、标记点到牙根尖距离、牙长、牙根凹陷直径4项指标,与原离体牙标本的游标卡尺测量结果进行统计学比较。结果:比较离体牙标本游标卡尺测量与螺旋CT三维重建测量结果,4项指标均有显著的统计学差异,螺旋CT三维重建测量值小于游标卡尺测量值,当数据精确到1 mm时,测量准确率可达到90%以上。结论:应用螺旋CT三维重建对离体牙进行长度测量,测量值略小于实际长度,将测量数据精确到1 mm时,准确率较高。

The reliability of accuracy of spiral CT three-dimensional reconstruction with extracted teeth in vitro.

Objective： The aim of this study is to analyze the accuracy of spiral CT three-dimensional reconstruction with extracted teeth in vitro. Method：20 extracted teeth from animal model were scanned and 3D reconstructed by CT, at the same time, the edge length of marker, the distance between reference point and tooth apex, the length of tooth and the diameter of depression of root were measured and compared with the measurement of extracted teeth without CT scanning by vernier caliper. Result： The results indicated that 4 indexes all had statistically significant. The measurement result of spiral CT 3D reconstruction was smaller than that of vernier caliper, when accuracy was 1 mm, the rate of precision could be above 90 %. Conclusion： The result of measurement with spiral CT 3D reconstruction was smaller than the real length of extracted teeth. When accuracy was lmm, the precision was high enough.