上颌尖牙根尖形态的CBCT研究

The study of the morphology of maxillary canine apical

目的:通过CBCT根尖影像资料研究腭侧阻生尖牙根尖带钩或弯曲的形态。方法:观察分析46例上颌腭侧阻生尖牙患者及52例位置正常的晚萌上颌尖牙(对照组)患者CBCT尖牙根尖影像资料。将CBCT数据DICOM文件导入Planmeca Romexis 3D软件中进行分析。在矢状面与冠状面观察尖牙根尖带钩或弯曲的方向,使用软件测量工具测量尖牙的牙冠、牙根长度以及根尖带钩的角度。结果:两组之间根尖带钩或弯曲的尖牙存在显著差异(P<0.05)。腭侧阻生尖牙组根尖带钩的尖牙有18颗(占30%)且多偏向近中(83.3%),根尖弯曲的尖牙仅有5颗(8.3%)。对照组根尖带钩的尖牙仅1颗,根尖弯曲尖牙有26颗(26%)且多偏向远中(50%)。腭侧阻生尖牙组尖牙平均根长较对照组短2.78 mm,尖牙冠/根比较对照组大(P<0.01)。结论:根尖带钩多见于腭侧阻生尖牙,且多偏向近中;根尖弯曲多见于正常晚萌尖牙,且多偏向远中。腭侧阻生尖牙较正常晚萌尖牙的冠/根比大。

Objective:To study the morphology of apical-hook or curved canine by CBCT images of palatal impacted canine and normal canine.Methods:CBCT was used to obtain canine images.The study included palatal impacted canine and control groups.The palatal impacted canine group included 46 patients with maxillary palatal impacted canines and the control group included 52 patients with delayed normal maxillary canine teeth.Import the DICOM file into Planmeca Romexis 3 D software for analysis.The apical hook or bending direction on the sagittal and coronal planes was observed.The length of crown and root, crown/root ratio and the angle of the apical hook was measured by using software measurement tools.Results:There were significant differences between the two groups of canines with apical hooked or curved(P<0.05).In the palatal impacted canine group, there were 18(30%)apical hooked and more mesial(83.3%),and only 5(8.3%)apical with curved roots.In the control group, there was only one apical hook, and 26 apical curved canine teeth(26%),which were more distant to the distal(50%).The average root length of the canine in the palatal impacted canine group was 2.78 mm shorter than that in the control group(P<0.01).The crown/root ratio of palatal impacted canine was larger than the canine group(P<0.01).Conclusion:Apical hooks are more common in the palatal impacted canine, and the apical hooks are more mesial, the apical curvature is more common in delayed normal canines, and the apical curvature is more distant.In addition, the palatal impacted canine has a larger crown/root ratio than the delayed normal canine.