Järvinen S
Am J Orthod. 1982 Mar;81(3):245-8. doi: 10.1016/0002-9416(82)90058-6.
The correlation between the NSAr and the SNA angles was studied in two separate samples. The first sample consisted of twenty young adults with excellent Class I (Angle) occlusion and proportionate facial skeleton, and the second sample consisted of sixty-one children with Class II, Division 1 (Angle) malocclusion. In the excellent-occlusion group, the correlation between the angles was remarkably higher (-0.94) than it was in the malocclusion group (-0.57). In both groups, in only a small number of cases were the extents of the angles close to the intersection of the calculated mean values. In orthodontic diagnosis, treating the values of the NSAr and the SNA angles separately can be extremely misleading, just as the use of the sella-nasion plane as a sole reference plane can lead to diagnostic errors. Thus, the SNA angle should be used with special caution, and a differing reference plane such as, for example, the Frankfort plane, should be preferred.
在两个独立样本中研究了NSAr角与SNA角之间的相关性。第一个样本由20名具有完美I类（安氏）咬合和比例协调面部骨骼的年轻成年人组成，第二个样本由61名患有II类1分类（安氏）错牙合的儿童组成。在完美咬合组中，这些角度之间的相关性（-0.94）明显高于错牙合组（-0.57）。在两组中，只有少数情况下角度范围接近计算出的平均值的交点。在正畸诊断中，单独处理NSAr角和SNA角的值可能会极具误导性，就像仅使用蝶鞍-鼻根平面作为唯一参考平面会导致诊断错误一样。因此，应特别谨慎地使用SNA角，并且应优先选择不同的参考平面，例如法兰克福平面。
