Teeth whitening is not something that should be done without consulting your dentist first, especially if you have had dental work done on your teeth in the past. There are several reasons for teeth to look discoloured or stained and some of those reasons will not respond to any whitening agent at all. What are they?
- Dental decay. Decays can make your teeth look as if they are stained, but the cause of the discolouration goes deep into the tooth. The decay must be filled before any whitening treatment is undertaken. Bleach can make a dental cavity worse.
- Caps or crowns. If you’ve had a broken tooth replaced by a cap or crown, it can become yellowish compared to your natural teeth, but whitening methods don’t work on it because it is not made from enamel and dentin, like normal teeth are. So while the surrounding teeth may become whiter after treatment, the cap will remain the same colour. In fact, it will probably look dingier in comparison.
- Extrinsic staining. Discolouration is due to two main problems; the tooth enamel becoming thinner and allowing the colour of the dentin to show through (intrinsic staining) and external staining from coffee, wine, smoking and so on(extrinsic staining). Bleaching your teeth addresses the first problem as the bleach is absorbed through the enamel of the teeth and lightens the dentin. It does not work for extrinsic staining.
So if you want to have whiter teeth, it’s best to consult with your dentist beforehand and ask them to identify the source of the discolouration and tell you if teeth whitening using bleach will work for you.
If the dentist okays you for whitening, you’ll need to decide whether to do a home treatment or have the dentist do it. Having the dentist do it is a safer option because he will be able to ensure the product does not get on your gums. This is more difficult to achieve at home. If your gums get bleached it will damage them and be very uncomfortable.
You also need to ensure that your teeth are not sensitive before you start because if they are, they’ll be even worse after treatment. Normally though, the sensitivity does not last more than 24 hours.
Teeth whitening is completely safe so long as it is done properly. You need to understand that leaving the product on your teeth longer than the time state on the bottle will not make your teeth whiter more quickly. Rather it will damage them. It is far safer to follow the instructions to the letter and end up with nice white teeth, than to risk damage. You only have one set of teeth as an adult so take care of them.