Abstract：
The main objective of the present research study is to evaluate the association between the occurrence of buccally displaced canine (BDC) and the palatal as well as the craniofacial morphology in adolescents in accordance at the early permanent dentition. As the experimental group, 100 adolescents of Chinese ethnicity (mean age 13.05 years) with crowding and buccally displaced canine (BDC-c) were selected in comparison with the same number of candidates (mean age 12.59 years) without BDC and crowding as control group. Digital dental casts and cephalograms were collected for three dimensional (3D) and cephalometric measurements. An independent sample T-test was used to compare the cephalometric values between the two groups. Logistic regression as commonly statistical methods used in empirical study including categorical dependent variables was used to identify the joint effects of the dental variables\' 3D measurements. When comparing the groups with above analysis, patients with BDC showed a statistically significant narrower and higher palatal vault. For the cephalometric variables, the anterior cranial base length, sagittal position of the maxilla (SNA), sagittal position of the mandible (SNB), and skeletal relationship between maxilla and mandible (ANB) appeared to be smaller, whilst palatal plane angle (SN-PP), Frankfort-mandibular plane angle (FMA), anterior facial height, and lower facial height were larger in BDC-c control group (p < 0.05). A smaller inter-first premolar width was significant in the prediction model (p = 0.002). This study highlights that BDC-c participants in early permanent dentition exhibited a narrower dental arch and higher palatal vault, of which a smaller inter-first premolar width would significantly increase the occurrence of BDC.
摘要：
本研究的主要目的是根据永久性牙列的早期，评估口腔移位犬（BDC）的发生与the和颅面形态之间的关系。作为实验组,选择了100名中国种族（平均年龄13.05岁）的拥挤和口腔移位犬（BDC-c）的青少年，与相同数量的没有BDC和拥挤的候选人（平均年龄12.59岁）作为对照组进行比较。收集数字牙模和头颅图进行三维（3D）和头颅测量。使用独立样本T检验比较两组之间的头颅测量值。逻辑回归作为经验研究中常用的统计方法，包括分类因变量，用于识别牙科变量的联合效应\'3D测量。当与上述分析进行比较时，BDC患者显示出统计学上显著的狭窄和较高的腭穹顶.对于头颅测量变量，前颅底长度，上颌骨矢状位置(SNA),下颌骨矢状位置（SNB），上颌骨和下颌骨（ANB）之间的骨骼关系似乎较小，而腭平面角(SN-PP)，法兰克福-下颌平面角（FMA），前面部高度,BDC-c对照组面部高度较低（p<0.05）。在预测模型中，较小的第一前磨牙间宽度是显着的（p=0.002）。这项研究强调，早期恒牙的BDC-c参与者表现出更窄的牙弓和更高的腭穹顶，其中较小的第一前磨牙间宽度将显着增加BDC的发生。
