The use of three-dimensional cephalometric references in dentoskeletal symmetry diagnosis

OBJECTIVE: The aim of this study is to assess dentoskeletal symmetry in cone-beam computed tomography (CBCT) scans of Brazilian individuals with Angle Class I malocclusion.MATERIAL: A total of 47 patients (22 females and 25 males) aged between 11 and 16 years old (14 years) seen in a private radiology service (CIRO, Goiânia, GO, Brazil) were assessed. All CBCT scans were obtained from January, 2009 to December, 2010. Cephalometric measurements were taken by multiplanar reconstruction (axial, coronal and sagittal) using Vista Dent3DPro 2.0 (Dentsply GAC, New York, USA). Minimum, maximum, mean and standard deviation values were arranged in tables, and Student t-test was used to determine statistical significance (P < 0.05).RESULTS: Data were homogeneous, and differences between the right and left sides were not significant.CONCLUSIONS: Cephalometric measurements of Brazilian individuals with Angle Class I malocclusion can be used to establish facial symmetry and three-dimensional standard references which might be useful for orthodontic and surgical planning.

### 研究目的
本研究旨在评估安氏Ⅰ类错𬌗畸形巴西受试者的锥形束计算机断层扫描（cone-beam computed tomography，CBCT）影像中的牙颌骨骼对称性。
### 研究材料
本研究共纳入47例患者（女性22例，男性25例），年龄介于11至16岁，平均年龄14岁，均就诊于巴西戈亚斯州戈亚尼亚市CIRO私人放射诊疗机构。所有CBCT影像采集于2009年1月至2010年12月。采用Vista Dent3DPro 2.0软件（登士柏GAC，美国纽约）通过轴位、冠状位及矢状位多平面重建进行头影测量。将最小值、最大值、均值及标准差整理为表格，并采用Student t检验进行统计学显著性分析（P<0.05）。
### 研究结果
本研究数据分布均一，左右两侧差异无统计学意义。
### 研究结论
针对安氏Ⅰ类错𬌗畸形巴西受试者的头影测量数据，可用于建立面部对称性及三维标准参考值，该参考值可为正畸及外科治疗方案的制定提供参考。