时间:2018-12-07 作者:英语课 分类:VOA慢速英语2009年(一)月


英语课
This is the VOA Special English Health Report.

Wisdom teeth are normally the last teeth to appear in the mouth. It usually happens when people are older and wiser. That is, when they are in their late teenage years or early twenties.

Wisdom teeth are molars, or chewing teeth at the back of the mouth. The third set of molars, if you have them, are your wisdom teeth.

They can grow into place normally and never cause a problem. But often there is not enough room for them in the mouth. They might crowd the other teeth. Sometimes they even push through the gums sideways.

An impacted wisdom tooth is one that fails to completely rise through the gums -- the term is erupt. Wisdom teeth that only partly erupt can leave space for bacteria to enter around the tooth. Infection is a risk in these cases.

Experts say people should have their mouths examined between the ages of sixteen and twenty for placement of their wisdom teeth. X-rays can show wisdom teeth below the gums. Those that are not well aligned 1 and become impacted are often removed.

The American Dental Association says removal is generally advised when wisdom teeth only partly break through the gums. Removal is also advised if there is a chance that poorly aligned wisdom teeth will damage other teeth. And removal is called for in cases where fluid collects around a wisdom tooth that is partly or fully 2 below the gum.

But why do we have wisdom teeth if we often need to get them removed? One theory has to do with our diets. Scientists say the diet of prehistoric 3 humans probably required more chewing teeth. Life was probably a little rougher on the teeth back then, too. So it was good to have extras.

The removal of wisdom teeth is performed by oral surgeons. They say if removal is advised, the best time to do it is before the teeth cause any problems or pain.

The American Association of Oral and Maxillofacial Surgeons says young adults are the best candidates for wisdom teeth removal. The group says older patients may be at greater risk for disease in the tissue surrounding the molars.

Patients can have general anesthesia during the operation. Or they might choose to have a local painkiller 4 and remain awake. It may depend on the condition of the wisdom teeth and the number to be removed.

After surgery, there can be swelling 5 of the gums and face and some pain. Both can be treated with cold wraps and medication.

And that's the VOA Special English Health Report, written by Caty Weaver 6. I'm Faith Lapidus.

1 aligned
adj.对齐的,均衡的
  • Make sure the shelf is aligned with the top of the cupboard.务必使搁架与橱柜顶端对齐。
2 fully
adv.完全地,全部地,彻底地;充分地
  • The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气,然后全部呼出。
  • They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。
3 prehistoric
adj.(有记载的)历史以前的,史前的,古老的
  • They have found prehistoric remains.他们发现了史前遗迹。
  • It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。
4 painkiller
n.止痛药
  • I shall persuade him to take the painkiller.我将说服他把药吃下去。
  • The painkiller only provides him a short respite from his pain.止痛药仅仅让他在疼痛中有短暂的疏解。
5 swelling
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。
6 weaver
n.织布工;编织者
  • She was a fast weaver and the cloth was very good.她织布织得很快,而且布的质量很好。
  • The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。
学英语单词
After-regeneration
akarit
anomalistic magnetic variation
arheism
atf oil
austausch coefficient (austausch)
B-MOPP
bill day
black drawing
Briggsia longicaulis
Caribbean Sea
charger
chlorocruorin
cock-a-bill
coloured scenery picture
cost of quality
cuff applying forceps
d)
Delaborne
dipping acid
distune
doubling of tones
end of the period
engineery
ethylene oxidation
exon trapping
fighting load
fine mica cloth
fosphenytoin
fulcrum pin washer
fungal pneumonia
guerrilla
hand-kept
hew to the line
hull penetration plan
hybrid multi-shock shield
hydrant
impostery
incensial
industrial consumer goods
inert support
input sequence
iones
It all depends
jig machine
Kelwood
line filling
lyre of fornix
Maisonneuve fracture
mandles
medical colour TV van
mellowingly
mietkasernes
mode chart
moral economy
motor-wagon
multispeed transmission
nomade
non flowing character
ocean floor
on line refuelling
optical fiber tensile strength
peacefulness
photographic recording
pipes of peace
plunger type clay gun
pop sb up
Porphyrobacter
positive-definite
presidential candidate
pressure hull
quinazolinyl
rami mammarii laterales
rate of change
re-organisation
registrar
Reichmann's rod
reticulo-angioma
rib and truck parrel
RR (repetition rate)
school edition
selenocarbonyl
self analysis
shrink head
single-collar thrust bearing
singstress
slumism
smart phones
stepped round nose pliers
sub-microns
sunheat
surcharge on each mu of land
ten-strike
toss for
trash closet
trichmonad
twin sideband
Ubraye
unsnatch
vertical combinations
vetoing
warm language