问题 多项选择题

影响全口义齿固位的主要因素有()

A.基托的边缘封闭作用

B.唾液分泌的质和量

C.颌骨的解剖形态

D.基托磨光面形态

E.口腔黏膜的性质

答案

参考答案:A, B, C, D, E

解析:全口义齿的固位原理:吸附力的大小和唾液的质和量有关系,如果唾液的黏稠度高,流动性小,可以加强附着力和内聚力,而增强义齿的固位。相反,如果唾液的黏稠度低,流动性大,则可减低固位作用。当两个物体表面之间的间隙愈小,所形成的半月形液体表面愈完全,表面张力也就愈大。在大气压力作用下,基托和组织密贴而使义齿获得固位。没有良好的边缘封闭就无大气压力作用可言。大气压力在全口义齿固位力中有重要作用。

阅读理解

阅读理解。

      Lots of people make it as their aim to get to the top of Mount Everest. Mark is one of them. The

difference between Mark and other climbers is that he lost both his legs when climbing. New Zealand's

highest mountain, Mount Cook. He was caught in a big ice hole and he had to have his legs cut below the

knees after he was saved. But that couldn't make Mark lose heart, who has become the first person with

man-made legs to reach the top of Mount Everest.

     From the top of the world's highest mountain, Mark called his wife to say he made it. His wife, Anne

got the phone when she was sleeping. She couldn't hear him clearly on the phone. She was unable to say

when he reached the top but thought it was around mid-day. She also said his "legs" didn't work well

sometimes, so her husband was carrying a spare leg and repair tools.

     Mark used to be a mountain guide before his accident. He said it was not important that no one like

him had ever reached the 8850-meter mountain.

     "I'm not doing this to be the first. I have been climbing most of my life and I just feel Mount Everest is

really a great aim. I want to send a message that I can do-anything better."

1. What was the difference between Mark and other climbers?

A. He went mountain-climbing with his wife.

B. He climbed mountains with man-made legs.

C. He was the first to climb Mount Everest.

D. He was the best guide of the world.

2. Mark's wife thought is was ________ on Mount Everest when Mark reached its top.

A. noon

B. morning

C. mid-night

D. evening

3. Which of the following is the correct order in Mark's story?

a. Losing both of his legs.

b. Working as a mountain guide.

c. Falling into an ice hole on Mount Cook.

d. Reaching the top of Mount Everest.

A. c a b d

B. c a d b

C. b c a d

D. b a c d

4. Mark's story makes us believe that he is a ________ man.

A. polite

B. brave

C. kind

D. clever

5. Mark told us that he cared much about ________.

A. being the first

B. climbing higher

C. keeping healthy

D. being a guide

选择题