Ihlow D, Dathe H, Fanghänel J, Proff P, Nägerl H, Hahn W, Kubein-Meesenburg D, Thieme K M
Department of Orthodontics, Georg August University Goettingen, Germany.
J Orofac Orthop. 2011 Oct;72(5):358-70. doi: 10.1007/s00056-011-0040-5. Epub 2011 Oct 12.
One way of determining the direction of growth of the mandible is to consider the temporomandibular joint and movement of the mandible as a four-joint gear system, regarding growth then as an extension of the gear system. Our aim was to examine any correlations between the type of biomechanical growth extension and change in the maxilomandibular relation after Class II therapy.
A total of 130 lateral cephalograms-before and after orthodontic treatment-were available from 65 adolescent class II patients with open bite or deep bite. The two lateral cephalograms from each patient were superimposed on the occlusal plane. Cephalometric values and the vertical base point deviation were determined from biomechanical analyses, together with three distances and three angles.
No correlation between the cephalometric data and distances or angles were observed. Although there were no significant differences in the distances, we did note significant differences in all three angles (p < 0.05).
If gear system extension during growth is considered, this can be interpreted as meaning that the occlusal plane of those patients with an initially open bite dropped during treatment, but that it rose in patients with an initially deep bite.
确定下颌骨生长方向的一种方法是将颞下颌关节和下颌运动视为一个四关节齿轮系统，将生长视为该齿轮系统的延伸。我们的目的是研究II类错 治疗后生物力学生长延伸类型与上颌下颌关系变化之间的相关性。
从65例开 或深 的青少年II类患者中获得了130张正畸治疗前后的头颅侧位片。将每位患者的两张头颅侧位片叠加在咬合平面上。通过生物力学分析确定了头影测量值和垂直基点偏差，以及三个距离和三个角度。
未观察到头影测量数据与距离或角度之间的相关性。虽然距离没有显著差异，但我们确实注意到所有三个角度都有显著差异（p < 0.05）。
如果考虑生长过程中的齿轮系统延伸，这可以解释为，最初开 的患者在治疗过程中咬合平面下降，而最初深 的患者咬合平面上升。
