Some expert tips on bleaching your teeth

Dr. Hall,
I have received various answers on retouching my bleached teeth with Opalescence PF used with trays. I want to do this before deciding on the color for crowns. I used 20%.

1. How long should I touch-up (for example, 1 week, 2 weeks)?
2. How many hours each day (1 hr., 2 hours, or 3 hours)?
3. Is it necessary to stop whitening a certain length of time before appointment (not necessary, 1 week, 2 weeks)?

Cathy from Texas

Cathy,
There is no real fixed answer on how long you should touch up with Opalescence 20% PF or any other brand of bleaching gel, and I’m concerned if you’re having these crowns done by a dentist who can’t answer these questions for you. I would have to see your teeth, know a little of the history, and know how white you want them. Is this really the dentist you want giving you a new smile? Is this a dentist with an engineering mentality who has little passion for appearance-related dentistry and who will leave you with a well-fitting smile that looks very mediocre – kind of like the photo on our home page? Or is your dentist a true artist, one of the 1-2% minority of dentists who will actually give you a beautiful smile?

Here’s the deal on teeth whitening and how much to do it. No one has found a real limit on how much you can whiten your teeth. The longer you whiten, the whiter they get. The pace of whitening slows the more you do it, but the teeth keep getting whiter. So if you were my patient and had questions like this, I would ask questions like how satisfied you are with the current color, how much you bleached them before, have the teeth darkened much since you first had them whitened, and then how much work you are willing to go through to get them to what you would consider to be their ideal whiteness.

And the amount of time each day you should whiten depends on whether or not you are getting sensitivity from the bleaching gel. Do them as long as you can, is the bottom line, as long as you’re not having any sensitivity. Now if you are sleeping, your saliva flow goes way down and the bleaching gel will stay in the trays much longer. One application should last through the night. You don’t need a gel that is specifically designed for nighttime use – they all contain peroxide. During the day, depending on how tightly your trays fit, saliva will get into the trays and wash out the gel, and you’ll need to keep replenishing it. You do need a minimum period of 20-30 minutes for the gel to soak into the tooth. Beyond that, the more the better.

The one fixed answer that I can give you is how long to stop whitening before any color-matching is done on the new crowns. The whitening is accomplished by the peroxide gel releasing tiny bubbles of pure oxygen within your tooth, and the oxygen oxidizes the stains and darker colors. Once you’ve completed the bleaching, you need to give time for those little oxygen bubbles to disperse in order to get a true color for the teeth, and that takes a couple of weeks. Now if you are doing eight front teeth, the color of the back teeth and the lower teeth doesn’t need to really match – it just needs to be close – and a week would be enough time to wait. But if you need an exact color match of a front tooth with a crown matched to another front tooth with natural enamel, you need to wait the full two weeks.

So what I’ve answered goes beyond simple teeth whitening touch-up. Once your teeth are whitened to the degree you want, then there is a certain amount of teeth whitening relapse that you will have, as the teeth pick up stains from your food – coffee, tea, berries, fruit juices, etc. But whitening for two or three days maybe an hour a day and doing that once every year or two should take care of that and enable you to maintain that bright white bleached color.

But again, I’m quite worried about what kind of work is going to be done on you. An excellent cosmetic dentist would have brought up this subject with you when the case was treatment-planned and would have covered all these points. Do NOT rely on the claims of a dentist about being a cosmetic dentist, or advertising. The problem with the dentists who don’t do very good appearance-related dentistry is that they aren’t artistically inclined and they are blind to their own shortcomings in this area. Dentists with strong academic credentials, dentists who are prosthodontic specialists, and dentists with “high standing” among other dentists can be particularly problematic. They may do highly functional, long-lasting dentistry with absolutely no artistic taste. Be careful.

Dr. Hall

Link: Click here to read our page about the home teeth bleaching procedure.