患者广泛性牙周炎,前牙Ⅰ至Ⅱ度松动,牙周袋深4.5mm,治疗方案为()。
A.切龈术
B.龈下洁治
C.翻瓣术
D.松牙固定术+洁治术
E.观察
参考答案:D
________ super hurricane of Sandy, sweeping across the USA and many parts of America, has up to now caused ________ loss of over 50 billion dollars to the USA alone.
A.The; the
B.A; the
C.The; a
D.A; a
优化设计的数学模型由_______、_______和_______三部分组成。