Objective:To investigate the effects of extraction to the morphology of symphysis and the relationship between lower incisors retraction and the changes of the symphysis by evaluating the cephalograms of patients with Angle Class II Division 1 malocclusion.
目的： 通过对安氏Ⅱ~1类错(牙合)拔牙矫治前后的X线头影测量分析，观察矫治前后颏部形态的变化，并探讨下切牙内收量与颏部厚度和倾斜度变化之间的相关关系，以期为临床矫治设计提供一定的参考。
Experimental investigation on cowl lip s open process of 2D inlet with different internal contraction ratios;
一组不同内收缩比二维进气道唇口开启过程实验研究
Objective:to observe the effect of bavarian dressing splint and paper circle external fixation to treating endoduction type surgical neck of humerus.
目的:观察石膏夹板配合纸圈外固定治疗内收型肱骨外科颈骨折的疗效。