Durão Ana Paula Reis, Morosolli Aline, Pittayapat Pisha, Bolstad Napat, Ferreira Afonso P, Jacobs Reinhilde
Department of Dental Radiology, Faculty of Dental Medicine, University of Porto, Porto, Portugal.
Department of Surgery, Dentistry School, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Imaging Sci Dent. 2015 Dec;45(4):213-20. doi: 10.5624/isd.2015.45.4.213. Epub 2015 Dec 17.
The aim this study was to compare the accuracy of orthodontists and dentomaxillofacial radiologists in identifying 17 commonly used cephalometric landmarks, and to determine the extent of variability associated with each of those landmarks.
Twenty digital lateral cephalometric radiographs were evaluated by two groups of dental specialists, and 17 cephalometric landmarks were identified. The x and y coordinates of each landmark were recorded. The mean value for each landmark was considered the best estimate and used as the standard. Variation in measurements of the distance between landmarks and measurements of the angles associated with certain landmarks was also assessed by a subset of two observers, and intraobserver and interobserver agreement were evaluated.
Intraclass correlation coefficients were excellent for intraobserver agreement, but only good for interobserver agreement. The least reliable landmark for orthodontists was the gnathion (Gn) point (standard deviation [SD], 5.92 mm), while the orbitale (Or) was the least reliable landmark (SD, 4.41 mm) for dentomaxillofacial radiologists. Furthermore, the condylion (Co)-Gn plane was the least consistent (SD, 4.43 mm).
We established that some landmarks were not as reproducible as others, both horizontally and vertically. The most consistently identified landmark in both groups was the lower incisor border, while the least reliable points were Co, Gn, Or, and the anterior nasal spine. Overall, a lower level of reproducibility in the identification of cephalometric landmarks was observed among orthodontists.
本研究旨在比较正畸医生和口腔颌面放射科医生识别17个常用头影测量标志点的准确性，并确定与每个标志点相关的变异程度。
两组牙科专家对20张数字化头颅侧位X线片进行评估，识别出17个头影测量标志点。记录每个标志点的x和y坐标。每个标志点的平均值被视为最佳估计值并用作标准。两名观察者的子集还评估了标志点之间距离测量值和与某些标志点相关角度测量值的变异情况，并评估了观察者内和观察者间的一致性。
组内相关系数在观察者内一致性方面表现优异，但在观察者间一致性方面仅为良好。正畸医生最不可靠的标志点是颏下点（Gn）（标准差[SD]，5.92mm），而眶点（Or）是口腔颌面放射科医生最不可靠的标志点（SD，4.41mm）。此外，髁突（Co）-Gn平面最不一致（SD，4.43mm）。
我们确定，一些标志点在水平和垂直方向上的可重复性不如其他标志点。两组中最一致识别的标志点是下切牙缘，而最不可靠的点是Co、Gn、Or和前鼻棘。总体而言，正畸医生在头影测量标志点识别方面的可重复性水平较低。
