螺旋CT多方式三维重建在上颌埋伏前牙定位中的综合应用

Comprehensive application of multi-pattern three-dimensional surface reconstruction of spiral CT in localizing impacted teeth of anterior maxilla

目的评价螺旋CT三维重建在上颌埋伏前牙定位诊断中的价值。方法对常规拍摄全颌曲面断层片和根尖片不易清楚判断埋伏牙形态、位置及与邻牙关系的72例患者,应用螺旋CT进行容积扫描,分别采用最大密度投影法(maximum in-tensity projection,MIP)、多平面重建(multi planar reconstruction,MPR)、容积再现法(volume rendering,VR)获得立体的牙体表面图像,显示上颌埋伏前牙的形态、位置及与邻牙的关系。结果经MIP、MPR、VR三种方式重建处理后,72例病例均清晰显示了上颌埋伏前牙的牙体形态、唇腭向位置、萌出方向以及与邻牙的关系。结论螺旋CT多方式三维重建的综合运用可为上颌埋伏前牙的定位诊断提供更为客观的依据。

Objective To evaluate the clinical value of three-dimensional surface reconstruction of spiral CT for localizing impacted teeth of anterior maxilla.Methods Spiral CT was performed in 72 cases whose anterior maxillary impacted teeth couldn′t be judged clearly through the panoramic radiograph or periapical film.Three-dimensional surface reconstruction,including MIP（maximum intensity projection）,MPR（multi planar reconstruction） and VR（volume rendering）,was made to display the impacted teeth′s shape,location and their relationship with adjacent teeth.Results In 72 cases,the reconstruction image,including crown,root,neck and root bifurcation in a three-dimensional way,showed labial or palatal location,eruption orientation and relation with dentition in anterior maxilla.Conclusions Comprehensive application of multi-pattern three-dimensional surface reconstruction of spiral CT is an accurate and effective method to examine impacted teeth of anterior maxilla.