1·Objective: To evaluate the clinical treatment effect of fractures in central section of face used of inner fixation diaplasis method through scalp coronoid incision.
目的观察面中部骨折，采用头皮冠状切口切开复位内固定治疗的临床效果。
2·It is proved that the R-rotation graph of a elementary coronoid system is a multiple directed rooted tree containing at least 2 trees.
如果冠状系统是基本的，已经证明其R -旋转图至少包含2棵有向根树。