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打磨牙釉质表面可以()

发布日期:2020-08-20

打磨牙釉质表面可以()
A

提高表面能

B

使釉面粗糙

C

增加粘接面积

D

以上都是

E

2分钟

试题解析

牙釉质

牙釉质:牙釉质是人体骨质中最坚硬的部分,包绕在牙冠表面,乳白色。它由细长的六棱柱状的釉柱及其间质规则的排列,故很致密。釉柱从牙釉质与牙本质的交界处向周围呈放射状走行,许多釉柱彼此扭曲成束,以致使在磨牙面上呈现出许多明暗相间的粗纹,即所谓施瑞格线。系牙钙化程度最高,最坚硬的部分。牙釉质包裹在牙冠的外面,约2~2.5mm厚,呈半透明状,质坚而脆。牙釉质分布往往不均衡,恒牙比乳牙多,牙浅表处比深处多,牙切缘或咬处比颈部多,这与牙的功能相适应。牙釉质主要由无机物质构成,其中有羟基磷灰石的结晶体和少量的氟磷灰石和钠、钾、镁的碳酸盐等化学成分。牙釉质对牙的功能具有重要意义,当其遭受破坏后,可使牙进一步遭到破坏。

中文名
牙釉质
别名
珐琅质
组成
95-97%由
外文名
dental enamel
定义
牙齿
作用
咬碎

打磨

打磨,是表面改性技术的一种,一般指借助粗糙物体(含有较高硬度颗粒的砂纸等)来通过摩擦改变材料表面物理性能的一种加工方法,主要目的是为了获取特定表面粗糙度。语出元无名氏《小尉迟》第一折。

中文名
打磨
拼音
dǎ mó
外文名
burnish/polish

表面

《表面》是由广东雨神演唱的一首歌曲,发布于2021年12月25日。

中文名
表面
歌曲原唱
广东雨神
谱曲
广东雨神
发行日期
2021年12月25日
歌曲时长
03分39秒
填词
广东雨神
编曲
孙鼐
歌曲语言
普通话

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