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
abietines
adhesion contracts
advance eccentric
advanced candu reactor
aguni i.
alternative current mechanism
amplitude mode
anteconsequent streams
atyrau oblysy
audio-visuals
backing support
beginning-block
benzyloxycarbonylglycine
blood is up
Boussinesq, Joseph
boxen
capponis
chemical fastness
Cinderellaesque
clock valve
container spray
cortical stimulator
cystic artery
dannen
DHSR
discovered
downdip
droplet nuclel
endless-belt
escort fees
extracytoplasmatically
finite closed interval
format element descriptor
formation bearing
graviation tank
hair-grasses
haptera
have eggs on the spit
imperial preferential tariff
inlapidating
internal-affairs
Ipolipid
iterative region
Ivanovice na Hane
jennifers
john lennons
L-N
lady from the sea
Laon
loss reinstatement clause
Maki Fumihiko
marking charge
metallic component
mineral waste residue
minimum-size
mount the throne
N-magnitude
no core reactor
non-parallels
nonrecurrent wave
noxious retentiontheory of immunity
oil dilution system
optimization of parallel process
orthodentine
perihelial
pesaroes
phase.locked.loop
pine sphinx moth
pitched preventer
polyporou
Pritzker Prize
prominentia laryngica
put one out
quantitative governing
radio interference
rear of queue
recording duration
redrier
Rehfuss test
safety cock
Sandy Pt.
Sarabetsu
sheaf of ring
shear diagrams
Shwebangon
star-tracking guidance
steam-chest
steersmen
stem-like
storminesss
sub-aerial
swallowing shock
Swedish modern
take it out of someone
thickening fibre
three-quarter coat
tirane
to bollock
upscale alarm
urotropine (hexamethylenetetramine)
wind gap
window based interface