PDF(Pubmed)
Abstract：
In cases of osseous defects, knowledge of the anatomy, and its age and sex-related variations, is essential for reconstruction of normal morphology. Here, we aimed at creating a 3D atlas of the human mandible in an adult sample using dense landmarking and geometric morphometrics. We segmented 50 male and 50 female mandibular surfaces from CBCT images (age range: 18.9-73.7 years). Nine fixed landmarks and 510 sliding semilandmarks were digitized on the mandibular surface, and then slid by minimizing bending energy against the average shape. Principal component analysis extracted the main patterns of shape variation. Sexes were compared with permutation tests and allometry was assessed by regressing on the log of the centroid size. Almost 49 percent of shape variation was described by the first three principal components. Shape variation was related to width, height and length proportions, variation of the angle between ramus and corpus, height of the coronoid process and inclination of the symphysis. Significant sex differences were detected, both in size and shape. Males were larger than females, had a higher ramus, more pronounced gonial angle, larger inter-gonial width, and more distinct antegonial notch. Accuracy of sexing based on the first two principal components in form space was 91 percent. The degree of edentulism was weakly related to mandibular shape. Age effects were not significant. The resulting atlas provides a dense description of mandibular form that can be used clinically as a guide for planning surgical reconstruction.
摘要：
在骨缺损的情况下，解剖学知识，以及年龄和性别相关的变化，对于重建正常形态至关重要。这里,我们的目标是使用密集的地标和几何形态计量学在成人样本中创建人类下颌骨的3D地图集。我们从CBCT图像中分割出50名男性和50名女性下颌表面（年龄范围：18.9-73.7岁）。在下颌表面上数字化了9个固定的标志和510个滑动的半标志，然后通过最小化弯曲能量来滑动平均形状。主成分分析提取了形状变化的主要模式。将性别与置换测试进行比较，并通过回归质心大小的对数来评估异速率。前三个主要成分描述了几乎49％的形状变化。形状变化与宽度有关，高度和长度比例，拉姆斯和语料库之间的角度变化，冠状突的高度和联合的倾斜度。检测到显著的性别差异，无论是大小还是形状。雄性比雌性大，有一个更高的ramus，更明显的角，较大的阴间宽度，和更明显的前庭凹口。基于形式空间中的前两个主成分进行性别划分的准确性为91％。无牙症的程度与下颌形状弱相关。年龄效应不显著。所得的图谱提供了下颌形式的密集描述，可在临床上用作计划手术重建的指南。
