Colour matching and tooth lightening

What is it?

The colour of your teeth can be lightened with modified Hydrogen Peroxide (bleach), used either on the outside or the inside of your tooth or teeth.

Like hair and skin, teeth vary in colour. Some are yellower or darker than others, even when they are quite healthy.

Teeth sometimes darken if their roots have been diseased. A change in colour is caused by blood from the root canal.

Tooth bleaching is completely safe as long as the bleach does not touch your gums and burn them. Dentists use a special jelly bleach.

What will my dentist/hygienist do?

For individual teeth that have discoloured after root canal, the bleach material is put in the root canal temporarily, before or after the tooth is root-filled, and a filling placed over the top- it may need several applications over a number of months, before the final permanent filling is placed. The results can avoid the need for a veneer or a crown but is unpredictable and in a small number of cases does not reach the shade desired.

There are two ways of bleaching the outside of teeth.

The dentist may give you weak bleach jelly to use at home in a tray which fits closely round your teeth. The tray makes sure that the jelly does not burn your gums. You will need to use the tray for an hour or two a day, for up to six weeks. 

Some kits come with ready made trays and for others a dental technician will make the tray you use for bleaching your teeth at home from an impression of your teeth that your dentist has made. Your dentist will check the tray fits and show you how to put the jelly in the tray at home.
Your dentist can use a stronger bleach jelly. Dentists use this method to bleach all the teeth at the same time in either your upper or lower jaw. The strong bleach will touch the teeth for less time than with home bleaching.
If your dentist uses a stronger bleach, they will protect your gums. They will paint the bleach onto the teeth and warm it with a light for a few minutes. They then wash it off with water.

Your dentist will make a note of your tooth colour using model teeth in different shades before they treat you. Look at the colour match yourself before the treatment so you can compare it with the colour after bleaching.
Your teeth may be sensitive to hot and cold food and drink for a few days after bleaching.

What are the benefits?

Bleaching improves the appearance of your teeth without removing any of the natural tooth surfaces. Bleaching is a better option than a crown or veneer if you want to lighten the colour of healthy teeth.
 

What are the limitations?

The results can be unpredictable, the lighter the teeth are to start with, the less effect the bleach will have. Some types of staining (like tetracycline stains and some other chemical inclusions in the enamel) don’t respond well to bleaching.