问题 单项选择题

全口义齿固位尚可,但在咀嚼食物时易脱位,原因最可能是()

A.基托边缘伸展不够,边缘不密合

B.基托过于密合

C.义齿边缘过长、过厚,系带缓冲不足

D.基托后部边缘伸展过长

E.义齿未达到平衡

答案

参考答案:E

解析:

全口义齿固位尚可,但在咀嚼食物时易脱位是由于不平衡,牙尖有干扰,使义齿翘动,破坏了边缘封闭造成的。修改时应当进行选磨调抬,消除牙的过早接触和牙尖的干扰,或将基托边缘磨短磨薄。

阅读理解

I love to tell the story about how I met my best friend---- Tiger. We met at the school fair. Each year, all the fourth-grade classes hold a school fair. Everyone in the fourth-grade works at the fair. Some sell ice cream, drinks and snacks. Others take care of the little children who ride the rides.

I got the second job and I’ve never regretted it, because that’s where I met Tiger.

My job was to help little children get on the back of a little horse. I kept telling the children to wait their turn and holding ice cream for them while they rode about. One thing was clear to me. I was growing older and should be more responsible.

Suddenly, a boy came to the horse. He took the little horse’s reins! The horse stopped, and the girl on its back started to fall. I was trying to reach the girl when I saw Tiger go by my legs. It held the horse’s reins and pulled the horse away from my legs. I caught the girl just before we both hit the ground. The girl sat on top of me. She was laughing at the ice cream on my face. The horse’s reins were in Tiger’s mouth!

Thanks to Tiger’s fast action, I saved the little girl. We were both heroes. And Tiger, the fastest dog I’ve even known became my new best friend.

小题1:According to the passage, __________ work at the fair.    

A.ice cream sellers

B.all the school children

C.little boys and girls

D.the fourth-grade students小题2:The writer’s job was to __________.

A.take the little horse’s reins

B.look after the children

C.get on the back of the horse

D.ride with little children小题3:As soon as the little horse stopped, the girl __________.

A.started to fall

B.laughed at the writer

C.hit the ground

D.sat on top of the writer小题4:Tiger helped to save the little girl on the horse by __________.

A.going fast by the writer’s legs

B.trying to catch the little girl

C.holding the reins with its mouth

D.riding the little horse around小题5:From the passage, we know that __________.

A.Tiger was a actually a brave dog

B.Tiger wanted to become a hero

C.the writer didn’t want to grow up

D.the writer regretted working at the fair

单项选择题