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
a pretty time of it
abelmoschus glutino-textilis kagawa
activation model of memory
Afrodescendant
allostimulatory
American Wirehairs
Amphistichus
angiomyeloma
auxiliary motor-pump assembly
basic recipe
beaucastel
book matches
bousouki
Busse-Buschke disease
casebier
Chirita gueilinensis
circular shaft
citronellyl valerate
city water
contrarians
conventional ration
coupling mirror
crosswind sensitivity
cygnus buccinators
data file format
driving mechanism
dust car
el quseima (al qusaymah)
follutein
full-floating gudgeon pin
gadolinium oxychloride
galectin
gallups
gas pipeline transportation service
gateman
genus Belamcanda
geological appraisal for water project
geomagnetic storm
gold bronze
Gopherus
gravimetric network
halituss
hay-scenteds
hemipyxis yuae
Homonoia
imbalantia
imbedment
imminent peril
kdp
kiasu
La Plata River
laminae dorsi nasi
Magwe
Mangoag
martec
mean ergodic semigroup
median root zone
merry-go-round machine
monoharmonic
neutral leach
Paralithodes
plantar intercuneiform ligaments
polyvalences
Predgornoye
preparative liquid chromatograph
presents and gifts
progressive honing machine
proliferative dermatitis
radio ranging
rapid adjustment
ratio of specific heats
renovative
rich as Croesus
rudderfishes
rules and regulations of cost accounting
running warn
semiclosed-cycle gas turbine
separate efficiency
shazad
sheathing strip
side lobe echo
Siemens-Halske system
simultaneous transmission of two languages on television
skiascopies
snowmould
snr bandwidth product
sow bugs
suctions
tabulating equipment simulator
telegraphic facsimile
thuricin
timing axis
Toxicodendron succedaneum
Tórtoles de Esgueva
unworthy to tie his shoestrings
USB Mini
vascular bud
vocational trainings
wideband system
Wörther See
Yur'yev-Pol'skiy
Zagwe Dynasty