【摘要】 目的:用锥形束CT(CBCT)在三维空间中定位阻生尖牙及确定最常见阻生类型,同时评估相邻切牙(中切牙和侧切牙)牙根吸收情况。方法:对63例患者92颗上颌阻生尖牙患者进行CBCT扫描,采用多平面重建(MPR)获得三维重建图像。在矢状、冠状、轴切面视图中,设定X,Y,Z平面,并对每个阻生尖牙牙尖定位,观察相邻切牙牙根吸收状况。结果:在X平面中:92%偏近中阻生,阻生距离10.4~15.1 mm,8%偏远中阻生,阻生距离2~5 mm;在Z平面中:60%偏腭侧阻生,阻生距离1~4 mm,40%偏唇侧阻生,阻生距离0~4 mm。相邻切牙牙根41.3%无吸收,36.5%轻微吸收,14.3%中度吸收,7.9%重度吸收。结论:上颌阻生尖牙最常发生于腭侧、近中,多伴有相邻切牙牙根吸收。更多还原

【Abstract】 Objective: To localize the impacted maxillary canine and to observe the root resorption of adjacent incisor in 3 dimensions using cone beam computed tomography( CBCT). Methods: 92 impacted maxillary canines in 63 patients were scanned by CBCT. The three-dimensional images were obtained by multiplanar reconstructions( MPR). The cusp tip of each impacted canine was localized and set to the X,Y and Z planes after the observation of sagittal,coronal and axial views. The root resorption of adjacent incisors was observed. Results: In the X-axis,92% of impactions were mesial by 10. 4 to 15. 1 mm,8% distal by 2 to 5 mm; in the Z-axis,60% of impactions were palatal by 1 to 4 mm,40% buccal by 0 to 4 mm. 41. 3% of the impacted canines were without root resorption of adjacent incisor,36. 5% with slight,14. 3% with moderate and 7. 9% with severe root resorption of the adjacent incisor. Conclusion: The most frequent location of impacted maxillary canine is palatal and mesial with high incidence of root resorption of adjacent incisor.更多还原