揭秘牙齿中的VIP 5类牙齿需重点保护
Some of our 32 adult teeth are more vulnerable to decay and damage than others. Here, London dentist Dr Charles Ferber reveals where the dangers lie.
你知道吗？在成人的32颗恒牙中，有的牙齿要更容易遭受损伤和腐蚀，想要有一口漂亮又健康的牙齿，除了日常的清洁护理之外，还应对这一类“VIP牙”进行重点保护。
INCISORS
门牙
Incisors are the eight teeth at the front of your mouth — four at the top, four at the bottom.
门牙是分布于口腔下颚前方的八颗牙齿，四颗在上，四颗在下。
PROBLEMS: The central incisors are most vulnerable, but those in the lower jaw are particularly affected by teeth grinding, which 8 per cent of us do unconsciously.
问题：位于中央位置的门牙是非常容易受到腐蚀的，而下颚的门牙则直接则特别容易遭受磨损。
Your lower central incisors are more -yellow because the enamel is thinner, revealing the yellowish tissue (dentine) that gives teeth their strength.
下门牙很容易呈现出黄色，这是因为珐琅质较薄而露出了黄色的组织，也就是牙本质的“真面目”，而这样以外便使得下门牙异常的坚硬。
The inside of these incisors is also particularly prone to tartar because there are -salivary glands here. Minerals in saliva combine with plaque to form hardened tartar. A build-up of tartar can cause -irritation that gradually makes the gum and jawbone shrink.
但因为唾液腺位置的缘故，门牙上也非常容易有牙垢的出现。唾液中的矿物质在结合之后，会形成硬化的斑块牙垢，而当牙垢积累到一定的程度之后，可能会引起牙龈与颚骨的萎缩。
CANINES
犬牙
These are the strongest teeth; their pointed shape makes them useful for shredding, cutting and tearing food. There are four: two on the top, two on the -bottom, on the side of the lateral incisors.
犬牙是最坚固的牙齿，锥形的构造让磨牙在碾碎、切断和撕裂食物方面“得心应手”，四颗犬牙上下平均分布，位于门牙的左右两边。
PROBLEMS: These contain more dentine to make them stronger so they are difficult to whiten.
问题：因为富含牙本质，所以犬牙也非常的坚固，但却也非常难以达到洁白光亮的效果。
PREMOLARS
前臼齿
Adults have eight premolar teeth, two next to each canine tooth in the upper and lower jaw. Their job is to chew and grind up food.
成人长有八颗前臼齿，分别位于上下颚犬齿后端，他们主要负责咀嚼与研磨食物的工作。
PROBLEMS: Premolars are more vulnerable to gum abrasions, caused by brushing teeth too harshly. This can lead to inflammation and, in the long term, gum -disease (causing teeth to fall out).
问题：错误的刷牙方式常常会致使前臼齿的牙龈“受伤”，久而久之，则会引起牙龈疾病（从而发生脱落的现象）。
MOLARS
臼齿
The molars are the largest teeth in the mouth and are also very strong — there are four at the top and four at the bottom.
臼齿是口腔内较大的牙齿，同样十分坚韧，分布于左右颊部后端，上下各四颗。
PROBLEMS: These are the most likely to need fillings because they are harder to reach when brushing; it’s a -problem for upper molars because salivary ducts in the cheek next to them produce saliva and this causes plaque to harden.
问题：位置靠内而难以清洁，所以臼齿是最需“补牙”的牙齿。而上臼齿十分接近脸颊两侧的唾液腺，因为十分容易导致牙菌斑的产生。
WISDOM TEETH
智齿
The largest teeth. Some people never develop them, others have up to four, one in each corner.
智齿是所有牙齿当中体积最佳的一种，有的人一辈子都不会长出智齿，而有的人则会在牙槽骨上最里面的上下左右各冒出一颗。
PROBLEMS: Sometimes wisdom teeth don’t erupt through the gums properly and a gum flap extends over the crown. Bacteria get stuck underneath this flap, making the area inflamed.
智齿常常不会“规矩”的顺着牙龈长出，而是在牙冠的一侧冒出一瓣牙龈。而“躲藏”在牙肉空隙之内细菌往往会造成这一区块出现红肿的现象。
