时间:2019-01-30 作者:英语课 分类:科技之光


英语课

SCIENCE IN THE NEWS - November 26, 2002: Dental Health


By Nancy Steinbach



VOICE ONE:
This is Steve Ember.
VOICE TWO:
And this is Bob Doughty 1 with Science in the News, a VOA Special English program about recent developments



in science. Today, we tell about diseases of the teeth and gums, and ways to prevent and treat them.



((THEME))


VOICE ONE:


People have been troubled by tooth and gum problems for thousands of years. The
earliest record of dental treatment comes from ancient Egypt. Books say the
Egyptians treated gum swelling 2 by using a substance made of spices and onions.
The earliest known person to treat tooth problems was also from Egypt. He lived
about five-thousand years ago. He was known as a “doctor of the tooth.


Experts say Chinese people living almost five-thousand years ago treated tooth pain by acupuncture 3 -- placing
small sharp needles in different parts of the body. About one-thousand-three-hundred years ago, the Chinese
filled holes in the teeth with a mixture of the metals mercury 4, silver and tin. That was almost one-thousand years
before a similar substance was first used in western countries. Some ancient people like the Maya did not treat
dental disease. But they made their teeth pretty by placing pieces of stone and metal on them.


VOICE TWO:


The ancient Romans were careful about keeping their teeth clean. More than two-thousand years ago, the
Romans treated toothaches, filled holes in teeth, and made false teeth to replace those that had been lost.


From the fifth to the fifteenth centuries, Europeans with tooth problems went to people called barber-surgeons.
These people performed many services, including cutting hair, pulling teeth and treating medical conditions.
Dental treatment improved during the fourteenth and fifteenth centuries as doctors increased their knowledge
about teeth.


((MUSIC BRIDGE))


VOICE ONE:


Modern dentistry began in the seventeen-hundreds in France. That was when Pierre Fauchard published his book
called "The Surgeon Dentist." It was the first book about dental science. The book provided information about
dental problems for other dentists to use. And it described ways to keep teeth healthy. Pierre Fauchard is
considered the father of modern dentistry. His work was important in helping 5 establish dentistry as a separate
profession.


Organized dentistry began in eighteen-forty. That is when the world’s first dental school opened in the
American city of Baltimore, Maryland. Four years later, a dentist first used drugs to ease the pain during dental
work. Two years after that, another dentist publicly demonstrated the use of the gas, ether, as a way to reduce
pain.


And in eighteen-fifty-eight, another American dentist invented a dental drill that was powered by stepping on a
device. This machine made it possible for dentists to use both hands when working in a patient’s mouth.




VOICE TWO:


In eighteen-ninety, an American scientist showed that bacteria in the mouth act on sugars that remain on the teeth
after eating. This action creates acid that damages the tooth. The damage appears as a hole in the tooth. It is
called a cavity 6. The part of the tooth that has been destroyed by the acid is inside the cavity. It is known as tooth
decay 7.


Tooth decay is common in the United States and around the world. Dental professionals say the acid remaining in
the mouth must be removed before it destroys the outer covering of the teeth. Dentists say the best thing people
can do for their teeth is to keep them clean. After eating, people should use a toothbrush or other device to clean
the teeth. Then they should use a thin string or dental floss to remove particles of food between the teeth. Visiting
a dentist every six months can help keep the teeth healthy and prevent cavities 8.


VOICE ONE:


Experts say the greatest improvement in dental health during the twentieth century began in the United States in
the early Nineteen-Hundreds. Dentists in the small western town of Colorado Springs, Colorado found that
children there had low rates of tooth decay. They discovered that the town’s water supply contained fluoride, an
element found in rocks and minerals. Public health researchers thought that adding fluoride to water in other
American cities could reduce the rates of tooth decay.


In Nineteen-Forty-Five, a test program began in the middle western state of Michigan. Ten years later, results
showed a fifty to seventy percent reduction in cavities in the children who drank water containing fluoride. Since
then, many studies have confirmed the value of fluoride. Today, most of the American water supply contains
fluoride. And international health organizations, including the World Health Organization, support water
fluoridation programs.


((MUSIC BRIDGE))


VOICE TWO:


Decay is not the only disease that can cause tooth loss. Another serious disease affects the gums, the tissue that
surrounds the teeth. It is also caused by bacteria. If the bacteria are not removed every day, they form a substance
that stays on the teeth. This substance is known as plaque 9.


At first, the gums appear to be swollen 10, and may bleed when the teeth are brushed. This can lead to serious
infection of the tissue around the teeth. The infection may damage the bone that supports the teeth and cause
tooth loss and other health problems. Studies have found that people with severe gum disease have an increased
risk of developing heart disease, diabetes 11 and stroke.


Gum disease can be treated by a special dentist called a periodontist. Periodontists are trained to repair the gum
areas that have been damaged. This can be painful and costly 12.


Dental health experts say the best thing to do is to stop gum disease before it starts. The way to do this is to clean
the teeth every day. People also should use dental floss to remove plaque from between the teeth. Most experts
also agree that another way to prevent tooth and gum problems is to eat foods high in calcium 13 and vitamins and
low in sugar.


((MUSIC BRIDGE))


VOICE ONE:


Scientists continue to develop better dental treatments and equipment. Improved technology may change the way
people receive dental treatment in the future. For example, dentists are now using laser light to treat diseased
gums and teeth. Dentists use computer technology to help them repair damaged teeth. Researchers have
developed improved methods to repair bone that supports the teeth. And genetic 14 research is expected to develop
tests that will show the presence of disease-causing bacteria in the mouth.


Such increased knowledge about dental diseases and ways to prevent them has improved the health of many
people. Yet problems remain in some areas. In industrial countries, minorities and other groups have a high level
of untreated dental disease. In developing countries, many areas do not have even emergency care services. The



World Health Organization says people in countries in Africa have the most tooth and gum problems.
VOICE TWO:
World Health organization experts say the dental health situation is different for almost every country in the



world. As a result, it has developed oral health programs separately for each area.
The W-H-O oral health program is mainly for people living in poor areas. It provides them with information



about mouth diseases and health care. It also studies preventive programs using fluoride in water, salt, milk and
toothpaste. And it explores ways to include dental health in national health care systems.
((MUSIC BRIDGE)
)
VOICE ONE:
Many governments and other organizations provide help so people can get needed dental health services. But



dental health professionals say people should take good care of their teeth and gums.
They say people should keep their teeth as clean as possible. They should eat foods high in calcium and fiber 15.



These include milk products, whole grain breads and cereals 16, vegetables, fruits, beans and nuts. Recent studies
have shown that eating nuts can help slow the production of plaque on the teeth.
Experts say these activities will help everyone improve their dental health throughout their lives.
((THEME)
)
VOICE TWO:
This SCIENCE IN THE NEWS program was written by Nancy Steinbach. It was produced by George Grow.



This is Bob Doughty.
VOICE ONE:
And this is Steve Ember. Join us again next week for more news about science in Special English on the Voice of



America.


 


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adj.勇猛的,坚强的
  • Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质:脾气倔强,性格刚强。
  • The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。
n.肿胀
  • Use ice to reduce the swelling. 用冰敷消肿。
  • There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。
n.针灸,针刺法,针疗法
  • Written records show that acupuncture dates back to the Song Dynasty.文字记载表明,宋朝就已经有了针灸。
  • It's known that acupuncture originated in China.众所周知,针灸起源于中国。
n.汞,水银,水银柱
  • The liquid we can see in thermometers is mercury.我们看到的温度计里的液体是水银。
  • Mercury has a much greater density than water.水银的密度比水大得多。
n.食物的一份&adj.帮助人的,辅助的
  • The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
  • By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。
n.洞,穴,凹处,龋洞
  • There's a cavity in the boy's tooth.这个男孩的牙上有一个洞。
  • The dentist carefully located the filling in the cavity.牙医小心地把填塞的东西放入牙洞里。
vi.腐烂,衰落;n.腐烂,腐朽,衰败状态
  • The vegetables have begun to decay.那些蔬菜已开始腐烂。
  • Our powers decay in old age.我们的体力在老年时就衰退。
腔,洞( cavity的名词复数 ); (龋齿的)洞
  • Cavities in teeth are caused by decay. 牙齿上的空洞是由龋蚀造成的。
  • The dentist filled several cavities in my teeth. 牙医给我的牙堵了好几个洞 excavation 指“挖掘的洞”,如:
n.饰板,匾,(医)血小板
  • There is a commemorative plaque to the artist in the village hall.村公所里有一块纪念该艺术家的牌匾。
  • Some Latin words were engraved on the plaque. 牌匾上刻着些拉丁文。
adj.肿大的,水涨的;v.使变大,肿胀
  • Her legs had got swollen from standing up all day.因为整天站着,她的双腿已经肿了。
  • A mosquito had bitten her and her arm had swollen up.蚊子叮了她,她的手臂肿起来了。
n.糖尿病
  • In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者,医生告诫他们不要吃糖。
  • Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。
adj.昂贵的,价值高的,豪华的
  • It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
  • This dictionary is very useful,only it is a bit costly.这本词典很有用,左不过贵了些。
n.钙(化学符号Ca)
  • We need calcium to make bones.我们需要钙来壮骨。
  • Calcium is found most abundantly in milk.奶含钙最丰富。
adj.遗传的,遗传学的
  • It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
  • Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
n.纤维,纤维质
  • The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
  • The material must be free of fiber clumps.这种材料必须无纤维块。
n.谷类食品,谷类;麦片粥
  • By cereals we mean wheat,oats,rye,barley,and all that.谈到谷物,我们指的是小麦、燕麦、黑麦、大麦之类的东西。
  • Wheat and rice are cereals.小麦和水稻是谷类植物。
学英语单词
a-c bias
artificial transition
ascogenous
bacterial plant disease
be meat and drink for someone
be symptomatic of
bird-arm
bivariate function generator
breise
buttfuck
by-passage
cellulose film
chandly
choke up with
column with constant cross-section
control diode
corpsing
creep crack
cross-bred
cruising horse-power
crural sarcoma
CubeSat
curli
dalin
differential receiver statics
din-dins
dire
Draw Sample
eases up
ex-users
fresh infusion of senna
gaitas
George Sandism
golfingia margaritacea margaritacea
gravity segregation
independent sample design
indicator pressure
indirect gap semicondutor
infighting
interfacial angle
invoice outward
keeners
Kuznets cycle
laparocystectomy
Lummus cracking process
Maakel Region
mabrouk
Masubia
Mazak alloys
medium-temperature salt bath rectifier
milliken conductor
miracle cure
monocolous
Moral de Calatrava
nanoresistor
non-homing-type rotary switch
nuisance values
optical-discs
penicillium janczewskii
persistent pesticide
plagueful
plagueship
practical esthetics
prior equity
produce a play
programming language extension
quarterline
quickbreads
re-advances
recueil
regular-season
repairing base
resilient drive
retiered
retirement table
revhead
Rhodo phyceae
right-front
rigid-tine rotary cultivator
riparias riparias
sack tap
Salsola tragus
sericite in powder
sex-conditioned inheritance
sham eating
silk gauze
socket cover
solidago spathulatas
spare wire
spheric scale
stereoblastula
stream flow routing
superintendent engineer
swizzles
thermal denaturation
Troyish
trufan
type ahead
ubundu (ponthierville)
venae hypogastrica
Xenoantibodies
Zonabris