Abstract:

Objective    To investigate whether there is an associasion between the second premolar congenital missing and the cervical skeletal abnormalities by lateral cephalometric panoramic radiographs. Methods    Select 56 patients with second premolar congenital missing as the experimental group，24 male and 32 female，the patients′  age between 14-42；250 patients with no congenital missing teeth（except the third molar）of Class I who had accepted orthodontic treatment as the control group，85 male and 165 female，the patients′  age between 18-36. Record the data of the first four cervical fusion and posterior arch defects by the lateral cephalometricradiographs，and record the premolar congenital missing by panoramic radiographs. The relationship between the abnormal cervical vertebra and the second premolar congenital missing was analyzed by Chi-square test. Results    The occurrence rate of the cervical fusion in experimental group was 58.9%，while in control group it was 13.2%. The occurrence rate in the experimental group was significantly higher than that of the control group（P < 0.05）；the occurrence rate of the posterior arch defects in the experimental group was 5.4%，while in the control group it was 2.8%，there being no significant difference between the two groups；the occurrence rate of the cervical fusion and the posterior arch defects in the experimental group was 3.6%，while in the control group it was 1.2%，there being no significant difference between the two groups Conclusion    There is an obviously increasing occurrence rate of the cervical skeletal abnormalities in patients with the second premolar congenital missing.

Key words: premolar congenital missing, cervical skeletal abnormalities, cephalometric radiogragh, panoramic radiograph

摘要：

目的    通过头影测量片检测第二前磨牙先天缺失与颈椎骨骼异常之间是否存在关联。方法    选取2002—2015年中国医科大学附属口腔医院正畸科就诊的第二前磨牙先天缺失的研究组患者56例，其中男24例，女32例；年龄14 ~ 42岁。无恒牙先天缺失（除第三磨牙外）且接受正畸治疗的安氏Ⅰ类患者250例对照组，其中男85例，女165例；年龄18 ~ 36岁。头颅侧位片记录前4个颈椎融合和后弓缺陷数据，曲面断层片记录第二前磨牙缺失情况。第二前磨牙先天缺失与颈椎骨骼异常之间的关系采用χ2检验进行分析。结果    研究组颈椎融合发生率为58.9%，对照组为13.2%，研究组显著高于对照组（P < 0.05）；研究组寰椎后弓缺陷发生率为5.4%，对照组为2.8%，两组差异有统计学意义（P < 0.05）；研究组颈椎融合合并后弓缺陷发生率为3.6%，对照组为1.2%，两组差异有统计学意义（P < 0.05）。  结论    第二前磨牙先天缺失患者颈椎骨骼异常发生率明显增加。

关键词: 第二前磨牙先天缺失, 颈椎骨骼异常, 头颅侧位片, 曲面断层片