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Technology Reduces Time in Dentist’s Chair
Medical robots help surgeons perform delicate operations more safely and with greater dexterity than with instruments manipulated by hand. Such sophisticated tools also help doctors work more quickly. One machine reduces the time it takes to manufacture dental crowns to just a couple of hours.
Computer-aided medical instruments are increasingly making life easier for doctors and their patients.
It used to be that the common but complicated procedure to get a tooth crown required several visits to the dentist’s office. While a dental technician was preparing the permanent replacement for a damaged tooth, the patient had to wear a temporary crown.
Since the mid-1980s, this procedure has gradually been taken over by robotic machines that reduce the job to just over two hours. Sitting in the dentist’s chair takes even less time.
“It’s about 12 minutes worth of chair time for the patient and the rest of the time it’s work that’s taking place outside the patient’s mouth,” said dentist Michael Silveus.
At his office in Northern Virginia, close to Washington, Silveus and his assistant prepare a patient’s tooth for a new crown.
The actual drilling takes about five minutes.
Instead of making the impression of the damaged tooth in a plastic material, Silveus uses a wand with a video camera to scan the tooth and the surrounding area.
At this point the computer takes over, designing the new crown and creating instructions for a robotic milling machine.
A porcelain cube, no larger than the tooth, is inserted between two precise drills, similar to the dentist’s drill, that grind away excess material, turning the cube into a perfectly matching tooth crown.
To harden, the crown must be baked at high temperature for about ten minutes. During that process, it also gets tinted to match the color of the neighboring teeth, so it is ready to be cemented in the patient’s mouth.
Patients are pleased with the result.
“It feels amazing. The tooth feels like my tooth,” said one patient.
Silveus said even this technology may someday become obsolete.
“The other thing we look forward to is genetic engineering and eventually cloning, so you can make the crown out of actually enamel, just like the patient’s natural teeth are,” said Silveus.
But for now, he said, his patients are happy to be able to get a new crown in just one visit.
词语分析
mount
困难程度：4星核心词语，属常用3000词
英汉讲解
v.登上；爬上；装上；上升
n.底板；爬上；支架；乘用马
n.山；峰
参考例句
用作动词
He mounted the horse and rode off.
他骑上马走了。
用作名词
The general had an excellent mount.
将军有出色的坐骑。
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commander
困难程度：2星扩展词语，属常用10000词
英汉讲解
n.司令官；指挥官
参考例句
用作名词
The commander ordered a counterattack.
司令官命令反攻。
The army was arrayed before the commander.
部队在指挥官前列好阵势。
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sufficient
困难程度：4星核心词语，属常用3000词
英汉讲解
adj.足够的；充分的
参考例句
用作形容词
The money I have saved is sufficient for buying a car.
我所存的钱足以买一辆汽车。
We must work hard, but equally we must get sufficient rest.
大家需要努力工作,但同时也要有充分的休息。
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absolutely
困难程度：3星常用词语，属常用6000词
英汉讲解
adv.完全地；绝对地；[语]独立地
int.（表示同意）完全正确，一点没错
参考例句
用作副词
I trust his discretion absolutely.
我完全相信他的判断。
Most researchers believe that, in theory, mobile phones are absolutely safe.
多数研究者觉得,从理论上讲,移动电话是绝对安全的。
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vehicle
困难程度：4星核心词语，属常用3000词
英汉讲解
n.汽车；交通工具；传播媒介；方法；工具
参考例句
用作名词
It is time for the yearly check of vehicle safety.
到汽车安全年审的时间了。
It subsequently evolved into an even more complex investment vehicle.
并随后进步成为一种更为复杂的投资方法。
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numerous
困难程度：3星常用词语，属常用6000词
英汉讲解
adj.为数海量的；很多
参考例句
用作形容词
The Earth is only one of the numerous planets in the universe.
地球只不过宇宙中海量星球中的一个。
Numerous interruptions have prevented me from finishing my work.
我屡遭搅扰以致工作未能完成。
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unwilling
困难程度：2星扩展词语，属常用10000词
英汉讲解
adj.不想的
参考例句
用作形容词
I am unwilling to set a precedent.
我不想开先例。
If you are unwilling, don't hesitate to say no.
假如你不想,请直说吧。
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