Godt Arnim, Müller Anett, Kalwitzki Matthias, Göz Gernot
Poliklinik für Kieferorthopädie, Eberhard-Karls-Universität, Tübingen, Germany.
Eur J Orthod. 2007 Dec;29(6):648-53. doi: 10.1093/ejo/cjm073. Epub 2007 Sep 18.
The objective of this study was to investigate whether it is possible to use a lateral (profile) photograph to determine the underlying skeletal Class and which reference points of the angle of convexity are most suitable for this purpose. Profile photographs and lateral cephalographs included in the baseline data for 180 orthodontic patients were retrospectively evaluated. The subjects were assigned to skeletal Classes based on Wits values obtained by radiolographic analysis. The Class I subjects were 58 patients (22 males, 36 females) with an average age of 13.63 +/- 2.1 years, the Class II subjects 60 patients (37 males, 23 females) with an average age of 13.60 +/- 2.6 years, and the Class III subjects 62 patients (28 males, 34 females) with an average age of 11.65 +/- 3.3 years. The angles measured were A'OrB' (=POrA'-POrA'), A'N'B', and the angle of convexity with its variants (N'SnPog', N'A'Pog', TrSnPog', TrA'Pog', Gl'SnPog', and Gl'A'Pog'). These angles were statistically evaluated using a two-sided t-test and linear discriminant analysis. Class II and Class III subjects exhibited highly significant differences (P < 0.001) for all angles. Class I and Class III exhibited highly significant differences (P < 0.001) for almost all angles, and significant differences for A'N'B' (P < 0.05). Class I and Class II differed significantly (P < 0.05) only for some angles (N'SnPog', TrA'Pog', Gl'SnPog', and Gl'A'Pog'). The error within the linear discriminant analysis was smallest for N'SnPog', GlA'Pog', and TrA'Pog' angles. However, the method error according to Dahlberg yielded rather high values for all angles (1.07-1.17 degrees). Discrimination between skeletal Class I and Class III was easier than that between Class I and Class II. One of the reasons may be that the subclasses division I and division II were not distinguished within the Class II subjects.
本研究的目的是调查是否可以使用侧面（轮廓）照片来确定潜在的骨骼错颌分类，以及凸度角的哪些参考点最适合此目的。对180名正畸患者基线数据中的侧面照片和头颅侧位片进行回顾性评估。根据放射学分析获得的Wits值将受试者分为骨骼错颌分类。I类受试者为58例患者（22例男性，36例女性），平均年龄13.63±2.1岁；II类受试者为60例患者（37例男性，23例女性），平均年龄13.60±2.6岁；III类受试者为62例患者（28例男性，34例女性），平均年龄11.65±3.3岁。测量的角度为A'OrB'（=POrA'-POrA'）、A'N'B'以及凸度角及其变体（N'SnPog'、N'A'Pog'、TrSnPog'、TrA'Pog'、Gl'SnPog'和Gl'A'Pog'）。使用双侧t检验和线性判别分析对这些角度进行统计学评估。II类和III类受试者在所有角度上均表现出高度显著差异（P<0.001）。I类和III类受试者在几乎所有角度上均表现出高度显著差异（P<0.001），在A'N'B'角度上表现出显著差异（P<0.05）。I类和II类仅在某些角度（N'SnPog'、TrA'Pog'、Gl'SnPog'和Gl'A'Pog'）上存在显著差异（P<0.05）。线性判别分析中误差最小的角度为N'SnPog'、GlA'Pog'和TrA'Pog'。然而，根据达尔伯格法得出的方法误差在所有角度上都相当高（1.07 - 1.17度）。骨骼I类和III类之间的区分比I类和II类之间的区分更容易。原因之一可能是在II类受试者中未区分亚类I和亚类II。
