问题 问答题 简答题

简述牙体缺损的修复治疗原则:正确地恢复形态与功能。

答案

参考答案:

1.轴面形态

(1)维持牙颈部龈组织的张力和正常接触关系。

(2)保证食物正常排溢道及食物流对牙龈的生理性刺激作用。

(3)利于修复体的自洁。

2.邻接关系牙冠修复体邻面与邻牙紧密接触,能防止食物嵌塞,维持牙位、牙弓形态的稳定,使之与邻牙互相支持,分散力,同时有利于每个牙在咀嚼时保持各自的生理运动。

(1)前牙接触区:位于靠近切缘,龈径大于唇舌径。

(2)第二前磨牙与第一磨牙近中接触区:位于邻面颊1/3与中1/3交界处。

(3)第一磨牙与第二磨牙的接触区:位于邻面中1/3。

3.外展隙和邻间隙

(1)外展隙

1)外展隙是指围绕邻接区向四周展开的空隙,是由牙冠轴面的正常突度形成的。

2)外展隙可作为食物的溢出道,在咀嚼时,有利于食物从外展隙排溢,增加机械便利,减轻牙周负担。

(2)邻间隙

1)邻间隙位于邻接点之下,被牙龈乳突所充满。

2)有保护牙槽骨和防止水平性食物嵌塞的作用。

4.面与咬合关系正确地恢复面形态和咬合关系,是有效地恢复咀嚼功能的基本条件之一。

良好咬合的标准:

(1)面形态的恢复应与患牙的固位形、抗力形以及与邻牙和对牙的面形态相协调。

(2)力方向应接近于牙的长轴。

(3)力的大小应与牙周支持组织相适应。

(4)具有稳定而协调的关系。

单项选择题

When I was six, Dad brought home a dog one day, who was called "Brownie". My brothers and I all loved Brownie and did different things with her. One of us would walk her, another would feed her, then there were baths, playing catch and many other games. Brownie, in return, loved each and every one of us. One thing that most touched my heart was that she would go to whoever was sick and just be with them. We always felt better when she was around.

One day, as I was getting her food, she chewed up (咬破) one of Dad’ s shoes, which had to be thrown away in the end. I knew Dad would be mad and I had to let her know what she did was wrong. When I looked at her and said, "Bad girl," she looked down at the ground and then went and hid. I saw a tear in her eyes.

Brownie turned out to be more than just our family pet. She went everywhere with us. People would stop and ask if they could pet her. Of course she’ d let anyone pet her. She was just the most lovable dog. There were many times when we’ d be out walking and a small child would come over and pull on her hair. She never barked (咬) or tried to get away. Funny thing is she would smile. This frightened people because they thought ’she was showing her teeth. Far from the truth, she loved everyone.

Now many years have passed since Brownie died of old age. I still miss the days when she was with us.

Why does the author say that Brownie was more than just a family pet()

 

A. Because she was treated as a member of the family.

B. Because she played games with anyone she liked.

C. Because she was loved by everybody she met.

D. Because she went everywhere with the family.

单项选择题