Compared with the impacted group, the erupted group had anteriorly positioned and larger maxilla and mandible, less ramus-corpus angle and more protrusive lower incisors.

• 正常萌发者较阻生者有较长而前突的上下颚，较小的下颚骨体下颚枝交角与较前倾的下颚中切齿角度。