Department of Oral and Maxillofacial Surgery, College of Dentistry, University of Illinois, Chicago, Ill.
Department of Oral and Maxillofacial Surgery, College of Dentistry, University of Illinois, Chicago, Ill.
Am J Orthod Dentofacial Orthop. 2019 Sep;156(3):337-344. doi: 10.1016/j.ajodo.2018.09.018.
Clinical evaluation of the midface including the paranasal and upper lip regions is highly subjective and complex. Traditional and 3-dimensional cephalometrics were not developed with the clinical appearance of these midfacial areas in mind and are therefore inappropriate surrogates for the clinical appearance of the midface, making them unsuitable as aids in diagnosing dentofacial deformities. The aim of this study was to evaluate traditional as well as newly defined landmarks and measurements and their correlation with clinical appearance of the midface.
Fifty-two subjects who underwent full-field cone-beam computed tomography were recruited for this study. A single examiner assessed each subject's midfacial region (paranasal and upper lip), and a second examiner obtained traditional and newly defined cephalometric measurements for each subject. Both examiners were blinded to each other's data throughout the study. Statistical analysis was performed to assess the correlations of the traditional and novel cephalometric measurements with clinical midfacial findings. The impact of the soft tissue thickness in the paranasal region was also analyzed. The performance of any classification derived from statistically significant variables was analyzed with the use of micro-F scores and area under the receiver operating characteristic curve (AUC).
Both traditional (SNA) and newly defined measurements (SN, SN, SN, SN) had no statistically significant correlation with clinical paranasal diagnosis. However, in the absence of upper lip procumbency or protrusion, SN and SN had statistically significant correlations with clinical paranasal diagnosis (P = 0.047 and P = 0.003, respectively). For upper lip analysis, both traditional (SNA) and newly defined measurements (SN) had strong correlations with clinical upper lip diagnosis (P < 0.001). All statistically significant cephalometric variables had good intra- and interobserver reliability (correlation coefficients ≥0.972 and ≥ 0.968, respectively) except SNA, which had a low interobserver reliability (correlation coefficient 0.739). Fitted models for paranasal and upper lip analyses showed low micro-F scores, indicating low precision and recall. However, AUC values of 0.7019 and 0.6362 for the paranasal and upper lip analysis, respectively, suggest improved performance of the model when properly trained with a larger sample size.
Newly defined measurements SN and SN correlated with clinical paranasal diagnosis only in the absence of upper lip procumbency and protrusion. SNA and SN were strongly correlated with clinical upper lip diagnosis. However, fitted models based on this study sample yielded low micro-F scores, making the fitted models currently unsuitable for anything besides correlation with clinical findings. A larger sample size will be necessary to further clarify the potential roles of these measurements, especially given the reasonable AUC values. The findings of this study demonstrate the highly subjective and relative nature of midfacial diagnosis and the importance of clinical judgment despite the potential utility of some traditional and new measurements.
中面部（包括鼻旁和上唇区域）的临床评估具有高度主观性和复杂性。传统的和三维的头影测量学并不是为了考虑这些中面部区域的临床外观而开发的，因此不能替代中面部的临床外观，不适合作为诊断牙颌面畸形的辅助手段。本研究旨在评估传统和新定义的标志点和测量值及其与中面部临床外观的相关性。
本研究招募了 52 名接受全视野锥形束 CT 检查的受试者。一名检查者评估每个受试者的中面部区域（鼻旁和上唇），另一名检查者为每个受试者获取传统和新定义的头影测量值。在整个研究过程中，两位检查者均对彼此的数据不知情。通过统计学分析评估传统和新型头影测量值与中面部临床发现的相关性。还分析了鼻旁区域软组织厚度的影响。使用微-F 分数和接收器操作特征曲线下的面积（AUC）分析源自具有统计学意义的变量的任何分类的性能。
传统（SNA）和新定义的测量值（SN、SN、SN、SN）与临床鼻旁诊断均无统计学显著相关性。然而，在上唇无前倾或突出的情况下，SN 和 SN 与临床鼻旁诊断具有统计学显著相关性（分别为 P=0.047 和 P=0.003）。对于上唇分析，传统（SNA）和新定义的测量值（SN）与临床上唇诊断均具有很强的相关性（P<0.001）。除 SNA 外，所有具有统计学意义的头影测量值均具有良好的观察者内和观察者间可靠性（相关系数分别≥0.972 和≥0.968），而 SNA 的观察者间可靠性较低（相关系数为 0.739）。鼻旁和上唇分析的拟合模型显示微-F 分数较低，表明精度和召回率较低。然而，鼻旁和上唇分析的 AUC 值分别为 0.7019 和 0.6362，表明当使用更大的样本量进行适当训练时，模型的性能有所提高。
在没有上唇前倾或突出的情况下，新定义的 SN 和 SN 测量值与临床鼻旁诊断相关。SNA 和 SN 与临床上唇诊断密切相关。然而，基于本研究样本的拟合模型产生的微-F 分数较低，使得拟合模型目前除了与临床发现相关外，不适合其他任何用途。需要更大的样本量来进一步阐明这些测量值的潜在作用，尤其是考虑到合理的 AUC 值。本研究的结果表明，中面部诊断具有高度主观性和相对性，尽管一些传统和新测量值具有潜在的效用，但临床判断仍然很重要。
