Madsen David P, Sampson Wayne J, Townsend Grant C
School of Dentistry, The University of Adelaide, Australia.
Eur J Orthod. 2008 Oct;30(5):532-40. doi: 10.1093/ejo/cjn031. Epub 2008 Jul 16.
Commonly used craniofacial reference planes such as Frankfort Horizontal (FH) and sella-nasion have shortcomings, including their variable interindividual orientation when related to true horizontal (HOR). Therefore, the aim of this study was to evaluate the potential usefulness of a range of craniofacial reference planes to HOR, including those which have not been investigated previously: the Krogman-Walker (KW) line, the neutral horizontal axis, the foramen magnum line, and the posterior maxillary plane. A sample of 57 (38 female, 19 males) consecutive, pre-treatment orthodontic subjects aged 12-18 years were photographically recorded in a standing mirror-guided natural head position (NHP). Cephalograms taken at the same time were traced, orientated to a plumb line (true vertical) transferred from the photograph, and measured. Descriptive statistical analysis including means and standard deviations (SDs) were used to describe average orientation and variability. Thirty-nine of these subjects were photographically recorded 2 months later to test the reproducibility of NHP. The results showed that the variability of the 11 selected craniofacial reference planes related to HOR was generally high. The planes illustrating the lowest variability to HOR were FH and the KW line with SDs of 4.6 and 4.7 degrees, respectively. These, however, showed approximately double the variation in NHP reproducibility (mean square error 2.1 degree). The KW line and palatal plane were also on average orientated closest to HOR. Therefore, the KW line and palatal plane are potential substitutes for the commonly used reference planes in the absence of a reliable NHP. However, NHP still represents a more valid craniofacial reference system than the investigated reference planes.
常用的颅面参考平面，如法兰克福平面（FH）和蝶鞍-鼻根平面存在缺点，包括与真正的水平面（HOR）相关时个体间方向变化较大。因此，本研究的目的是评估一系列颅面参考平面相对于HOR的潜在实用性，包括那些以前未被研究过的平面：克罗格曼-沃克（KW）线、中性水平轴、枕骨大孔线和上颌后平面。对57名（38名女性，19名男性）年龄在12至18岁的连续正畸治疗前受试者进行样本采集，在站立位镜子引导的自然头位（NHP）下进行摄影记录。同时拍摄的头颅侧位片进行描图，根据从照片转移过来的铅垂线（真正的垂直方向）进行定向并测量。采用包括均值和标准差（SD）的描述性统计分析来描述平均方向和变异性。其中39名受试者在2个月后再次进行摄影记录，以测试NHP的可重复性。结果表明，所选的11个颅面参考平面相对于HOR的变异性普遍较高。相对于HOR变异性最低的平面是FH和KW线，标准差分别为4.6度和4.7度。然而，这些平面在NHP可重复性方面的变化约为两倍（均方误差2.1度）。KW线和腭平面平均方向也最接近HOR。因此，在没有可靠的NHP的情况下，KW线和腭平面可能是常用参考平面的潜在替代品。然而，NHP仍然是比所研究的参考平面更有效的颅面参考系统。
