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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.
詞匯解析
mount
難度：4星核心詞匯，屬常用3000詞
英漢解釋
v.登上；爬上；裝上；上升
n.底板；爬上；支架；乘用馬
n.山；峰
參考例句
用作動(dòng)詞 (v.)
He mounted the horse and rode off.
他騎上馬走了。
用作名詞 (n.)
The general had an excellent mount.
將軍有出色的坐騎。
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commander
難度：2星擴(kuò)展詞匯，屬常用10000詞
英漢解釋
n.司令官；指揮官
參考例句
用作名詞 (n.)
The commander ordered a counterattack.
司令官命令反攻。
The army was arrayed before the commander.
部隊(duì)在指揮官前列好陣勢(shì)。
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sufficient
難度：4星核心詞匯，屬常用3000詞
英漢解釋
adj.足夠的；充分的
參考例句
用作形容詞 (adj.)
The money I have saved is sufficient for buying a car.
我所存的錢足以買一輛汽車。
We must work hard, but equally we must get sufficient rest.
我們必須努力工作,但同時(shí)也要有充分的休息。
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absolutely
難度：3星常用詞匯，屬常用6000詞
英漢解釋
adv.完全地；絕對(duì)地；[語(yǔ)]獨(dú)立地
int.（表示贊同）完全正確，一點(diǎn)沒(méi)錯(cuò)
參考例句
用作副詞 (adv.)
I trust his discretion absolutely.
我完全相信他的判斷。
Most researchers believe that, in theory, mobile phones are absolutely safe.
多數(shù)研究者認(rèn)為,從理論上講,移動(dòng)電話是絕對(duì)安全的。
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vehicle
難度：4星核心詞匯，屬常用3000詞
英漢解釋
n.車輛；交通工具；傳播媒介；手段；工具
參考例句
用作名詞 (n.)
It is time for the yearly check of vehicle safety.
到車輛安全年審的時(shí)間了。
It subsequently evolved into an even more complex investment vehicle.
并隨后發(fā)展成為一種更為復(fù)雜的投資手段。
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numerous
難度：3星常用詞匯，屬常用6000詞
英漢解釋
adj.為數(shù)眾多的；許多
參考例句
用作形容詞 (adj.)
The Earth is only one of the numerous planets in the universe.
地球只是宇宙中眾多星球中的一個(gè)。
Numerous interruptions have prevented me from finishing my work.
我屢遭攪擾以致工作未能完成。
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unwilling
難度：2星擴(kuò)展詞匯，屬常用10000詞
英漢解釋
adj.不愿意的
參考例句
用作形容詞 (adj.)
I am unwilling to set a precedent.
我不想開(kāi)先例。
If you are unwilling, don't hesitate to say no.
如果你不愿意,請(qǐng)直說(shuō)吧。
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