Match 8th is _____.[ ]
A. Teachers' Day
B. Women's Day
C. Christmas Day
答案:B
in your position, I would help him.
A.Was I
B.Were I
C.If I am
D.If I had been
暂时性错发生机制是()
A.恒切牙萌出初期,出现轻度拥挤现象,可能因恒牙较乳牙大,随着颌骨的增大和乳磨牙与前磨牙的替换等变化可自行调整
B.多生牙占据了恒牙的位置,常引起恒牙的错位萌出
C.唇系带异常可造成上中切牙之间出现间隙
D.咬上唇习惯容易形成前牙反,下颌前突及近中错等畸形
E.以上都不是