Lee Kyung Jin, Jeon Hyeran Helen, Boucher Normand, Chung Chun-Hsi
Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA 19104-6030, USA.
J Imaging. 2022 Apr 5;8(4):100. doi: 10.3390/jimaging8040100.
Objectives: To study the transverse widths of maxilla and mandible and their relationship with the inclination of first molars. Materials and Methods: Fifty-six untreated adults (12 males, 44 females) with normal occlusion were included. On each Cone Beam Computed Tomography (CBCT) image of the subject, inter-buccal and inter-lingual bone widths were measured at the levels of hard palate, alveolar crest and furcation of the first molars, and maxillomandibular width differentials were calculated. In addition, the buccolingual inclination of each first molar was measured and its correlation with the maxillomandibular width differential was tested. Results: At the furcation level of the first molar, the maxillary inter-buccal bone width was more than the mandibular inter-buccal bone width by 1.1 ± 4.5 mm for males and 1.6 ± 2.9 mm for females; the mandibular inter-lingual bone width was more than the maxillary inter-lingual bone width by 1.3 ± 3.6 mm for males and 0.3 ± 3.2 mm for females. For females, there was a negative correlation between the maxillomandibular inter-lingual bone differential and maxillary first molar buccal inclination (p < 0.05), and a positive correlation between the maxillomandibular inter-lingual bone differential and mandibular first molar lingual inclination (p < 0.05). Conclusions: This is a randomized clinical study on transverse analysis of maxilla and mandible in adults with normal occlusion using CBCTs. On average: (1) At the furcation level of the first molars, the maxillary inter-buccal bone width was slightly wider than mandibular inter-buccal bone width; whereas the mandibular inter-lingual bone width was slightly wider than maxillary inter-lingual bone width; (2) A statistically significant correlation existed between the maxillomandibular transverse skeletal differentials and molar inclinations.
研究上颌骨和下颌骨的横向宽度及其与第一磨牙倾斜度的关系。材料与方法：纳入56例未经治疗的咬合正常的成年人（12例男性，44例女性）。在受试者的每张锥形束计算机断层扫描（CBCT）图像上，于硬腭、牙槽嵴及第一磨牙根分叉水平测量颊侧和舌侧骨宽度，并计算上下颌宽度差异。此外，测量每颗第一磨牙的颊舌向倾斜度，并测试其与上下颌宽度差异的相关性。结果：在第一磨牙根分叉水平，男性上颌颊侧骨宽度比下颌颊侧骨宽度多1.1±4.5mm，女性多1.6±2.9mm；男性下颌舌侧骨宽度比上颌舌侧骨宽度多1.3±3.6mm，女性多0.3±3.2mm。对于女性，上下颌舌侧骨差异与上颌第一磨牙颊侧倾斜度呈负相关（p<0.05），与下颌第一磨牙舌侧倾斜度呈正相关（p<0.05）。结论：这是一项使用CBCT对咬合正常的成年人上颌骨和下颌骨进行横向分析的随机临床研究。平均而言：（1）在第一磨牙根分叉水平，上颌颊侧骨宽度略宽于下颌颊侧骨宽度；而下颌舌侧骨宽度略宽于上颌舌侧骨宽度；（2）上下颌横向骨骼差异与磨牙倾斜度之间存在统计学上的显著相关性。
