Your pearly whites not so pearly anymore?您的珍珠白人并非如此珍珠了吗？ That can happen to any of us, for any number of reasons.这可以发生在我们任何人，任何的原因很多。 The good news is that you don't have to live with a smile you're less than happy with.好消息是，你没有生活微笑着你不到满意。 Tooth whitening can restore your teeth to their earlier brightness.美白可以恢复你的牙齿，以他们早先的亮度。 But given the number of options and the cost and time involved with each one, how do you know which one is right for you?但是，鉴于一些选择和费用和时间参与每一个，你怎么知道哪一个是正确的吗？

As we age, the outer layer of enamel on our teeth is worn away, eventually revealing the darker tissue underneath, at the center of the tooth around the nerves and blood vessels.正如我们的时代，外层的珐琅质对我们的牙齿以外破旧，最终揭示了黑暗的组织下，在中央的牙齿周围的神经和血管。 Our teeth may also become discolored from smoking, from drinking coffee, tea, and wine, and even from taking certain medications as a child such as tetracycline.我们的牙齿也可能成为变色吸烟，饮用咖啡，茶，葡萄酒，甚至采取某些药物作为一个儿童，如四环素。

"It's like wearing a great outfit or wonderful accessory," says Wynn Okuda, DMD, national president of the American Academy of Cosmetic Dentistry (AACD). “这就像一个伟大穿着服装或配件奇妙说， ”永利奥田硕，营养不良，国家主席，美国科学院整形牙科（ AACD ） 。 "Having your teeth whitened makes you feel good." “在你的牙齿白让你感觉很好。 ”

Almost everyone wants whiter teeth these days, adds Melissa Ing, DMD, associate professor of prosthodontics at the University of Connecticut Health Center.几乎每个人都希望白牙这些天，增加了梅利莎英，营养不良，副教授修复在康涅狄格大学卫生中心。 "It's the number one aesthetic concern of my patients," she says. “这是一个审美一些关心我的病人， ”她说。

Ing is not alone in noticing the upsurge in requests for a brighter smile.英不单单是发现了高潮要求一个更加光明的微笑。

That may be because it's fairly easy to accommodate those requests, says Ing.这可能是因为它很容易适应这些要求，说英。 "Tooth whitening or bleaching works for most people and my patients who have done it are happy with the results." “美白工程或漂白对于大多数人来说，和我的病人谁做得非常高兴的结果。 ”

Two Ways to Tooth Whitening两种方法来美白

Tooth whitening can be achieved in two ways.美白才能实现的方法有两种。 A product can bleach the tooth.产品可以漂白牙齿。 That means it actually changes the natural tooth color, usually anywhere from five to seven -- but even up to twelve -- shades brighter, which is how dentists assess tooth color.这意味着，它实际上改变了天然牙的颜色，通常是由地方五至七年-甚至高达1 2-色彩明亮，这是如何评估牙医牙齿的颜色。 Bleaching products contain peroxides that help remove both deep and surface stains.漂白产品含有过氧化物，有助于消除双方深，表面污渍。 The second whitening process uses non-bleaching products that work by physical or chemical action to help remove surface stains only.第二美白过程中使用非漂白产品工作的物理或化学的行动，有助于消除表面污迹只。

A newcomer to the world of tooth whitening is known as chairside bleaching.一个新手的世界美白称为chairside褪色。 This may require more than one visit, with each visit lasting 30 to 60 minutes.这可能需要一个以上的访问，每次访问持久30至60分钟。 During chairside bleaching, your dentist applies either a protective gel to your gums or a rubber shield to protect the soft tissues in the mouth.在chairside漂白，您的牙医也适用于凝胶保护您的牙龈或橡胶盾牌，保护软组织的嘴。 A bleaching agent is then applied to the teeth, and a special light may be used to enhance the action of the agent.阿漂白剂，然后应用到牙齿，和一个特别轻可用于提高的行动代理人。

The cost of professional whitening varies -- depending on where you live, what product the dentist uses, and what other services may be offered), but usually starts about $500 per session, says Okuda.成本的专业美白不同-这取决于你生活在那里，什么产品牙医使用，以及其他服务可以提供） ，但通常始于约5 00美元每会议上，奥田硕说。 If your teeth aren't very dark or very stained, you may need only one session.如果您的牙齿不是很暗或很染色，您可能只需要一个会议。

Your dentist can also provide you with a tooth-whitening system that you can use at home.您的牙医也可以为您提供牙齿美白系统，您可以使用在家里。 At-home products typically come in a gel form that contains carbamide peroxide; the gel is placed in a custom-fitted mouthguard, created from a mold of your teeth.在回家的产品通常有一种凝胶体形式，其中包含过氧化脲;凝胶是放置在一个定制的安装mouthguard ，创建模具的牙齿。 Depending on the product you and your dentist choose, the guard is worn either twice a day for 30 minutes or overnight -- usually for a couple of weeks.根据不同的产品您和您的牙医选择，警卫磨损或者是每天两次30分钟或隔夜-通常是几个星期。 The length of time can range from one week to one month depending on how much whitening you need.的时间长度可以从一个星期至一个月取决于有多少你需要美白。 This procedure usually costs around $400 and whitens the teeth four to seven shades.这一程序通常费用为400美元和whitens牙齿6点56分深浅。