美白牙齒 (一) tooth whitening part 1

漂牙分為家居漂白(home bleaching) 或者診所漂白(in-office bleaching)。


家居漂白(home bleaching)


診所漂白(in-office bleaching)



在仔細講述它們分別之前，先講兩個重點

Home bleaching 和 in-office bleaching 能夠達到相同效果。(Basting 2012)

為什麼呢? 原來要漂白牙齒用得物質是  carbamide peroxide/ hydrogen peroxide。
只要有足夠時間和濃度就可以達到相同效果。(前題是牙齒條件也合適)濃度愈高，所需時間愈少。濃度愈低，所需時間愈多。
簡單來說，效果 = 時間 X 濃度


美白程度(End point) 要看本身牙齒。
意思說是有end point 的，漂到某一個點就不能再白不會一路長期漂牙能夠戰勝人體極限。漂到某一個點就不能再白

那麼那種會適合我?

1. 如果你是心急的，想很快見到效果/ 不久後有重大事項 big event ，那麼你就可以讓醫生幫你做漂牙(in-office bleaching)，然後考慮用 home bleaching 做follow up 。為甚麼需要 follow up? 其中一個原因是日常我們進食的食物會令牙齒美白效果減退。

2. 如果你有時間但不想花太多金錢 ( long on time, short on money) ，那麼可以考慮做 home bleaching 。

最後要提醒一下，在香港只有香港持牌牙醫才可以替病人進行漂牙的。根據本港法例第一五六章《牙醫註冊條例》第三條，任何人如非註冊牙醫而在香港以牙醫身分執業，即屬犯罪，一經循簡易程序定罪，可處罰款十萬元及監禁三年。

********************************************************************************

Bleaching is classified as home bleaching or in-office bleaching.




Home bleaching






In-office bleaching



Before going into the details, let’s talk about two important points.

Home bleaching and in-office bleaching can achieve the same effect. (Basting 2012)


Why? The substance used to bleach teeth is carbamide peroxide / hydrogen peroxide.

As long as there is sufficient time and concentration, the same effect can be achieved. (assumption is being that the teeth are healthy and suitable for whitening.) The higher the concentration, the less time it takes. The lower the concentration, the more time it takes.

In simple terms, effect = time X concentration



The degree of whitening (End point) depends on the teeth.

It means that there is an end point. If you reach to a certain point, you can no longer be white. Just like there is an Olympic record, the teeth can't be whitened any more at a certain point.



So which one would suit me?


1. If you are anxious and want to see the effect soon or there will be a big event soon, then you can ask the doctor to help you do in-office bleaching, then consider using home bleaching to follow up Why do you need to follow up? One of the reasons is that the food we eat everyday will reduce the whitening effect of teeth.


2. If you have time but don't want to spend too much money (long on time, short on money), you can consider doing home bleaching.


Finally, I would like to remind you that in Hong Kong, only licensed dentists in Hong Kong can perform tooth bleaching for patients.  According to Article 3 of the Dentist Registration Ordinance, Chapter 156 of the Laws of Hong Kong, anyone who is not a registered dentist and practises as a dentist in Hong Kong commits an offence and is liable on summary conviction to a fine of $ 100,000 and to imprisonment of year.


Source:
1.  Basting RT, et. al. Clinical comparative study of the effectiveness of and tooth sensitivity to 10% and 20% carbamide peroxide home-use and 35% and 38% hydrogen peroxide in-office bleaching materials containing desensitizing agents. Oper Dent. Vol. 37, No. 5. September 2012.