【摘要】 目的:运用锥形束CT(cone-beam CT,CBCT)测量分析骨性Ⅱ类错青少年上颌第二前磨牙与第一磨牙之间不同截面的最小根间距及颊侧骨皮质表面与根间最窄处距离,为临床上微种植体的安全植入提供参考。方法:选取44例骨性Ⅱ类错青少年患者的CBCT资料,其中,男23例,女21例,平均年龄14.07岁。取上颌第二前磨牙与第一磨牙根间的9个水平截面,每个截面相距1 mm,分别测量每个截面的最小根间距及颊侧骨皮质表面与根间最窄处距离。采用SPSS 20.0软件包对测量结果进行统计学分析。结果:每个截面最小根间距和颊侧皮质骨表面与根间最窄处的距离,男女之间无显著差异(P>0.05),左右两侧无统计学差异(P>0.05);左侧根尖部的骨皮质表面与根间最窄处距离,与SNA角呈正相关关系;最小根间距离由釉-牙骨质界(cementoenamel junction,CEJ)至根尖逐渐增大,各截面的颊侧皮质骨表面与根间最窄处距离的均值均大于5 mm。结论:经CBCT获取了骨性Ⅱ类错青少年上颌第二前磨牙与第一磨牙之间各截面最小根间距和颊侧骨皮质表面与根间最窄处距离,了解了其分布规律,为临床上微种植体的安全植入提供了参考。更多还原

【Abstract】 PURPOSE: The purpose of this study was to measure the interradicular spaces between the maxillary second premolar and first molar in adolescents with skeletal Class Ⅱ malocclusion, so as to obtain scientific knowledge for placing mini-implants. METHODS : Forty four cone-beam computed tomography(CBCT) images were selected, which consisted of 23 males and 21 females(average age, 14.07 years) with skeletal Class Ⅱ malocclusion. CBCT was used to measure the closest interradicular distance and the shortest distance from cortical bone surface to the narrowest interradicular space apically at 1-mm intervals in 9 axial images from the cementoenamel junction(CEJ). SPSS 20.0 software package was used for statistical analysis. RESULTS: There was no significant difference in the closest interradicular distance and the shortest distance from cortical bone surface to the narrowest interradicular space between the left and right side(P>0.05), and no significant difference was found between males and females(P>0.05); The shortest distance from cortical bone surface to the narrowest interradicular space of the left apical area had positive correlation with SNA angle; The closest interradicular distance became wider toward the apical area,and the average distance of the shortest distance from cortical bone surface to the narrowest interradicular space was over 5 mm in all sections.CONCLUSIONS: The distribution of interradicular spaces between the maxillary second premolar and first molar of adolescents with skeletal Class Ⅱ malocclusion is learned using CBCT. These data might provide a reference for placing mini-implants.更多还原