The study examines a sample of patients presenting for viscerocranial computer tomography that does not display any apparent signs of asymmetry, assesses the three-dimensional congruency of the mandibular ramus, and focuses on differences in age and gender. This cross-sectional cohort study screened viscerocranial CT data of patients without deformation or developmental anomalies. Segmentations were obtained from the left and right sides and superimposed according to the best-fit alignment. Comparisons were made to evaluate three-dimensional congruency and compared between subgroups according to age and gender. Two hundred and sixty-eight patients were screened, and one hundred patients met the inclusion criteria. There were no statistical differences between the left and right sides of the mandibular ramus. Also, there were no differences between the subgroups. The overall root mean square was 0.75 ± 0.15 mm, and the mean absolute distance from the mean was 0.54 ± 0.10 mm. The mean difference was less than one millimetre, far below the two-millimetre distance described in the literature that defines relative symmetry. Our study population displays a high degree of three-dimensional congruency.

中文翻译：

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下颌支对称性的三维测量

该研究检查了进行内脏计算机断层扫描的患者样本，这些患者没有显示出任何明显的不对称迹象，评估了下颌升支的三维一致性，并重点关注年龄和性别的差异。这项横断面队列研究筛选了无变形或发育异常患者的颅内脏 CT 数据。从左侧和右侧获得分割并根据最佳拟合对齐进行叠加。进行比较以评估三维一致性，并根据年龄和性别在亚组之间进行比较。筛选了 268 名患者，其中 100 名患者符合纳入标准。左右两侧下颌支的差异无统计学意义。此外，亚组之间没有差异。总体均方根为 0.75 ± 0.15 mm，与平均值的平均绝对距离为 0.54 ± 0.10 mm。平均差异小于一毫米，远低于文献中定义相对对称性的两毫米距离。我们的研究人群表现出高度的三维一致性。