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 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 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 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 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 of the gums and face and some pain. Both can be treated with cold wraps and medication. 

    智齒通常是最后長出的牙齒。人們在青少年晚期或20歲出頭的年歲最容易長智齒,這時候人的年紀大了,也更有智慧,所以稱之為智齒。

    智齒屬于臼齒,長在口腔后側用來磨碎食物。通�？谇粌葲]有足夠的適于智齒生長的空間,因此他們常常會擠撞其他牙齒。有時甚至會側面頂著牙齦生長。

    無法長出或萌出的智齒稱為阻生牙。僅有部分萌出的智齒周圍容易產生細菌感染。

    專家建議人們應在16-20歲之間檢查智齒生長的位置。X光可以清楚地顯示牙齦下智齒的情況,咬合不均衡或會成為阻生牙的多會被拔除。

    美國牙醫學會建議出現以下情況時將智齒拔掉:智齒無法完全萌出牙床時;咬合不均衡的智齒有可能侵犯鄰牙時;流質食物殘渣堆積堆積在部分或全部位于牙床以下的智齒時。

    既然我們需要拔掉智齒,為什么還會長智齒呢?一個理論認為這與人類的飲食有關�？茖W家們介紹,遠古時代,食物比較粗糙,人們需要更多的咀嚼類牙齒來幫助磨碎食物。

    智齒拔除手術由牙醫們完成。他們認為最好選擇智齒尚未引起任何疼痛和問題的時候進行手術。

    美國口腔頜面外科醫師協會表示應盡量選擇年輕時進行手術,年紀越大,引發臼齒周圍組織感染的幾率越大。

    手術時可以選擇全身麻醉,或者吃止痛藥,保持清醒。這取決于智齒的情況以及要移除的數量。

    手術后牙床和臉部會腫脹,并伴有疼痛。可使用冷毛巾或吃消炎藥。