關(guān)于牙齒美白你應(yīng)該知道的一些事

Ask Well: Whiter Teeth

關(guān)于牙齒美白你應(yīng)該知道的一些事

Question: What is the healthiest and most effective way to whiten your teeth?

問：想要美白牙齒，最健康且最有效的方法是什么?

Answer: There is no shortage of ways to treat tooth discoloration: strips, rinses, brush-on gels and toothpastes sold at pharmacies; bleaching treatments at the dentist; trays bought at the dentist’s office for home use. The bottom line is all these methods work, but some require patience, and others a tolerance for painful sensitivity. And results will be only temporary.

答：治療牙齒變色的方法有很多：藥店出售的美白牙貼、漱口水、牙齒美白凝膠和牙膏;到牙科診所做牙齒漂白;或者從牙科診所購買適合家庭使用的美白牙托等?；旧险f，上述所有方法都有用，不過它們要么起效慢，需要付出點(diǎn)耐心;要么需要忍受令人不舒服的牙齒敏感。效果維持的時間也很短暫。

Higher concentrations of hydrogen peroxide, a bleaching agent used in many whiteners, can be delivered in a dentist’s office, so those procedures tend to be quicker than drugstore aids. But tooth sensitivity and gum irritation can occur, and the higher the concentration of the peroxide used, the more severe these side effects are likely to be.

在牙科診所里進(jìn)行的程序可能會用到高濃度的過氧化氫(許多增白劑中都含有的一種漂白劑)，因此往往比從藥店中買到的產(chǎn)品見效更快。但它們可能會引起牙齒敏感和牙齦發(fā)炎，而且所使用的過氧化物濃度越高，副作用可能就越嚴(yán)重。

More aggressive treatment isn’t necessarily more efficacious, either. A randomized trial of 90 patients found that use of a home bleaching tray with a 10 percent carbamide peroxide gel for two weeks offered the same degree of whitening as two in-office sessions using 35 percent hydrogen peroxide with light, which some dentists use because it supposedly activates bleaching agents.

較為積極的治療手段效果未必就更好。一項以90名患者為研究對象的隨機(jī)試驗發(fā)現(xiàn)，使用含10%過氧化脲(碳酰胺過氧化氫)的家用美白牙托兩周對牙齒的漂白效果，與在牙科診所做兩個35%過氧化氫加光美白療程(據(jù)說光可以激活漂白劑，所以某些牙醫(yī)會使用它)的效果相同。

Some dentists also use heat or even lasers to activate bleaching agents. But a 2007 systematic review of evidence in the journal Dental Materials found no added benefit from heat, light or lasers and suggested these methods “may have an adverse effect on pulpal tissue,” the soft material in the tooth’s center. If pulp is injured, it may require a root canal to fix.

一些牙醫(yī)也使用熱甚至激光來激活漂白劑。但2007年發(fā)表在《牙科材料學(xué)》雜志(Dental Materials)上的一篇對有關(guān)證據(jù)的系統(tǒng)性綜述顯示，熱、光或激光都不能帶來額外的增益，并指出這些方法“可能對牙髓組織(牙齒內(nèi)部的軟組織)造成不良影響”。如果牙髓受到損傷，可能會需要進(jìn)行根管治療。

Heat and hot lights can also have a dehydrating effect on teeth, which can make them look whiter. It can take weeks for the teeth to rehydrate and slightly darken.

熱和熱光也會造成牙齒脫水，使其看起來更白。牙齒復(fù)水大約需要幾周的時間，而且這會使牙齒稍微變暗。

Dr. Ronald D. Perry, the director of the Gavel Center for Restorative Research at Tufts University School of Dental Medicine, said that over all, “the light doesn’t really do anything, but the marketing behind it is so powerful.”

塔夫茨大學(xué)牙醫(yī)學(xué)院Gavel牙科修復(fù)研究中心(Gavel Center for Restorative Research at Tufts University School of Dental Medicine)的主任羅納德·D·佩里博士(Dr. Ronald D. Perry)說，總而言之，“光并沒有什么真正的效果，但它背后的市場營銷卻非常強(qiáng)大。”

Before any bleaching, even when it’s done at home, a dentist should check fillings and crowns, because, Dr. Perry said, applying peroxide to a restoration that is no longer perfectly sealed will be very sensitive.

在進(jìn)行任何牙齒漂白程序(哪怕是在家里進(jìn)行)之前，牙醫(yī)應(yīng)檢查牙齒填充物以及牙冠，佩里博士說，這是因為，如果牙體修復(fù)物不再完全密封，對其施用過氧化氫將會造成嚴(yán)重的敏感。

In a 2014 review of tooth whitening studies, Clifton Carey, a professor at the University of Colorado School of Dental Medicine, warned that fillings that are designed to match the tooth’s color might get more yellow after even drugstore whiteners. Or, if teeth get whiter, and a filling doesn’t, it might stand out.

在2014年的一項對牙齒美白研究的綜述中，科羅拉多大學(xué)牙醫(yī)學(xué)院(University of Colorado School of Dental Medicine)的教授克利夫頓·凱里(Clifton Carey)警告說，即使使用從藥店購買的增白劑，也可能使原本與牙齒顏色相匹配的牙體修復(fù)物變得更黃。又或者，牙齒被漂白了，沒有同樣被漂白的牙齒填充物就會變得很顯眼。

Not all staining is alike. It can be caused by external factors like wine, coffee, cola and smoking, and bleaching is effective against these. Aging is another culprit, as enamel wears down and the yellower dentin that lies beneath becomes visible. Bleaching does work on older teeth, too.

此外，各種牙漬也不是完全一樣的。它可能是由外部因素，如酒、咖啡、可樂和吸煙引起的，做牙齒漂白對這類牙漬很有效。衰老是牙齒變黃的另一個原因：隨著牙釉質(zhì)的磨損，其下顏色較黃的牙本質(zhì)顯露了出來。做牙齒漂白對此也有一定效果。

Unfortunately, it’s tricky to say how long the results of tooth whitening will last. A nightly merlot drinker with freshly lightened teeth may re-stain them in a month or two.

遺憾的是，很難說牙齒美白的效果能持續(xù)多久。如果每晚都飲用梅洛葡萄酒(merlot)，那么不出一兩個月，剛被洗白的牙齒可能就又被染回去了。