【作者】 于淼；

【导师】 杨陆一；

【作者基本信息】 吉林大学 ， 口腔医学（专业学位）， 2021， 硕士

【摘要】 研究目的:通过锥形束计算机成像技术(Cone-beam computed tomography,CBCT)对骨性Ⅲ类错(?)下颌中切牙冠根形态进行分析,探讨不同唇倾度的骨性Ⅲ类错(?)下颌中切牙冠根形态的特征,并分析下中切牙冠根形态与其相应的牙槽骨形态的相关性,为正畸临床诊疗提供参考。研究方法:从拍摄CBCT的患者中随机选取对照组正常(?)患者15例(男9例,女6例,平均年龄21.6岁),实验组骨性Ⅲ类错(?)患者40例(男23例,女17例,平均年龄18.9岁),并且将实验组根据下中切牙唇倾度不同分为舌倾组和直立组2个亚组,测量下颌中切牙冠根角、冠长、根长、冠根比和实验组牙槽骨形态。用SPSS 23.0软件进行统计分析,计量资料用均数±标准差(χ ±s)的形式表达。对照组和实验组的下切牙冠根形态比较和实验组中的舌倾组和直立组的下切牙冠根形态比较用独立样本t检验;实验组中的冠根形态与牙槽骨形态的相关性分析应用Pearson进行分析,P<0.05代表差异有统计学意义。研究结果:1、实验组冠根角小于对照组(P<0.01);2、骨性Ⅲ类错(?)患者直立组冠根角小于舌倾组(P<0.01),直立组根长大于舌倾组(P<0.05);3、骨性Ⅲ类错(?)患者冠根形态与牙槽骨形态有不同程度的相关性(P<0.05)。研究结论:1、骨性Ⅲ类错(?)患者下颌中切牙冠根成角明显,并且直立组和舌倾组中的下颌中切牙冠根形态存在显著差异;2、骨性Ⅲ类错(?)患者下颌中切牙冠根形态与牙槽骨形态有显著相关性。更多还原

【Abstract】 Objective:The purpose of this study is to investigate the crown-root morphology of mandibular central incisor in skeletal Class III malocclusion by cone-beam computed tomography(CBCT)and explore the characteristics of the crown-root morphology in different labial-lingual inclination of mandibular central incisor,and analyze the correlation between the crown and root morphology of mandibular central incisor and the corresponding alveolar bone morphology,so as to provide references for clinical diagnosis and treatment of orthodontics.Methods:Patients were selected randomly from those who had been received CBCT,with 15 normal patients in the control group(9 males and 6 females with an average age of 21.6 years)and 40 patients with skeletal class III malocclusion in the experimental group(23 males and 17 females with an average age of 18.9 years).Further,the experimental group was subdivided into the lingual inclination group and erection group according to different labial inclinations of the lower central incisor.The crown-root angle,crown length,root length and crown-root ratio of the mandibular central incisor and the corresponding alveolar bone morphology of the experimental group were measured.The SPSS 23.0 software was adopted for statistical analysis.Measurement data were expressed by mean ± standard deviation(χ±s).The independent samples t-tests were adopted to compare the crown-root morphology of mandibular central incisor between the control group and the experimental group,and between the lingual inclination subgroup and the erection subgroup in the experimental group.The correlation analysis between the crown and root morphology of mandibular central incisor and the corresponding alveolar bone morphology in the experimental group were tested by pearson correlation test.P<0.05 indicates a statistically significant difference.Results:1.The collum angle in the experimental group is smaller than that in the control group(P<0.01);2.In the patients with skeletal class Ⅲ malocclusion,the crown-root angle in the erection group was smaller than that in the lingual inclination group(P<0.01);the root length in the erection subgroup is longer than that in the lingual inclination subgroup(P<0.05);3.Among the patients with skeletal class Ⅲ malocclusion,the crown-root morphology was correlated with the corresponding alveolar bone morphology at different degrees(P<0.05).Conclusion:1.The crown-root angle of the mandibular central incisor is obvious in patients with skeletal class Ⅲ malocclusion,and the crown-root morphology of the mandibular central incisor is significantly different between the erection group and the lingual inclination group.2.There is a significant correlation between the crown-root morphology of the mandibular central incisor and the corresponding alveolar bone morphology in patients with skeletal class Ⅲ malocclusion.更多还原