曲面体层片中种植体影像失真率的实验研究

An experimental study of panoramic radiographs in dental implant

目的分析头颅位置变化对失真率的影响。方法在成年人颅骨标本的牙槽窝内放入种植体,拍摄标本在不同位置时的曲面体层片后测量种植体的宽度及长度。结果随着头颅位置的改变,种植体的水平和垂直失真率均发生了变化,水平失真率的变化更加明显。不同区域的水平失真有较大差异:前牙区最大,均值为-16.4%;磨牙区最小,均值为-4.2%。垂直失真率变化相对较小。结论不同区域有不同的失真率,头颅位置的改变对失真率有明显影响。

Objective The aim of this study was to quantify the vertical and horizontal distortion in panoramic radiographs in various implant regions of the jaws. Methods Five implants with the same length were placed in alveolar sockets of two human cadavers, in vitro.When implants were installed in the incisor, premolar and molar region of the jaws respectively, the specimens were taken radiographs on three different positions by moving the specimens anterior and posterior on the base of routine position. The length and diameter. of each implant were measured in each image. Results In all the regions, the horizontal and vertical distortion altered with different position of the specimen, but the change of the horizontal distortion was more severe. The mean ratios of horizontal and vertical distortion of panoramic radiographs were - 16.4% and 14.6%, - 7.1% and 15.8%, - 4.2% and 17.9% in the incisor, premolar and molar region,respectively. Conclusion The images displayed different distortions in different regions.The change of the position affected the horizontal and vertical distortion of panoramic radiographs.