Discipline of Radiology, Department of Diagnostic and Surgery, São Paulo State University-UNESP, São José dos Campos, São Paulo, Brazil.
Am J Orthod Dentofacial Orthop. 2011 Jun;139(6):e523-31. doi: 10.1016/j.ajodo.2010.10.020.
The aim of this study was to evaluate craniofacial asymmetry by using 2-dimensional (2D) posteroanterior cephalometric images, 3-dimensional cone-beam computed tomography (CBCT), and physical measurements (gold standard).
Ten dry human skulls were assessed, and radiopaque markers were placed on 17 skeletal landmarks. Twenty linear measurements were taken on each side to compare the right and left sides and to compare these measurements with the physical measurements made with a digital caliper. To acquire the 2D posteroanterior radiographs, an Extraoral Phosphor Storage Plate (Air Techniques, Chicago, Ill) was used as the image receptor with a Eureka x-ray-Duocon Machlett unit (Machlett Laboratores, Chicago, Ill). Three-dimensional imaging data were acquired from a CB MercuRay (Hitachi Medical, Tokyo, Japan).
On average, the right side was larger than the left for most of the 20 distances evaluated in the digital 2D and the CBCT images, and there was poor agreement between the digital 2D images and the physical measurements (kappa = 0.0609) and almost perfect agreement (kappa = 0.92) between the CBCT and physical measurements when individual measurements were considered.
Human skulls, with no apparent asymmetry, had some differences between the right and left sides, with dominance for the right side but with no clinical significance. CBCT can better evaluate craniofacial morphology when compared with digital 2D images.
本研究旨在通过二维（2D）前后位头颅侧位片、三维锥形束 CT（CBCT）和体格测量（金标准）评估颅面不对称。
对 10 个干燥人头颅骨进行评估，并在 17 个骨骼标志点上放置不透射线标记物。在每一侧测量 20 个线性测量值，以比较右侧和左侧，并将这些测量值与使用数字卡尺进行的体格测量值进行比较。为了获取 2D 前后位射线照片，使用外照射磷光存储板（Air techniques，芝加哥，伊利诺伊州）作为图像接收器，使用 Eureka x 射线-Duocon Machlett 装置（Machlett Laboratores，芝加哥，伊利诺伊州）。三维成像数据来自 CB MercuRay（日立医疗，东京，日本）。
平均而言，在数字 2D 和 CBCT 图像评估的 20 个距离中，大多数右侧大于左侧，数字 2D 图像与体格测量值之间的一致性较差（kappa = 0.0609），而 CBCT 与体格测量值之间的一致性几乎完美（kappa = 0.92），当考虑个体测量值时。
没有明显不对称的人头颅骨，右侧和左侧之间存在一些差异，右侧占主导地位，但没有临床意义。与数字 2D 图像相比，CBCT 可以更好地评估颅面形态。
