Whitening a Discolored Tooth from the Inside Out
posted: May 06, 2012.
If you have discolored teeth, the cause is often staining on the enamel surfaces from foods, beverages, or smoking. But tooth discoloration may also originate deep within the root of a tooth. Sometimes this happens to a tooth that had to have earlier root canal treatment because of injury or decay.
In such cases the living pulp tissue and its blood vessels and nerves had to be removed from the root canals, resulting in the death of the dentin layer, which makes up most of the tooth's body. Over time this caused the dentin to darken. The color may come from remains of blood that was left in the tissue, or from filling materials left in the root canal that are showing through.
Since these stains are caused internally (intrinsic) and not on the outside of the tooth (extrinsic) they must be whitened from the inside. This is usually done by putting a bleaching agent into the empty chamber from which the pulp was removed. Usually the bleaching agent is a substance called sodium perborate.
When it is mixed with a solution of hydrogen peroxide, sodium perborate slowly bleaches the color from the tooth's internal material. It is considered to be safe and reliable for this use.
The work begins by taking x-ray images to make sure that the root canal is correctly sealed and the bone is healthy. After this, we will make a small hole in the back of the tooth through which the root canal space will be cleaned. The root canal space will be sealed and the bleach will be applied in a putty-like form and sealed off from the rest of your mouth. Every few days this procedure will be repeated until the bleaching reaches the desired level.
At this point a tooth-colored composite resin will be used to seal the small hole that was made in the dentin to insert the bleach. After the tooth has reached the level of whiteness that matches it to your other teeth, veneers or crowns must sometimes be used to repair the surface if it is chipped or misshapen, for example.
Contact us today to schedule an appointment to discuss your questions about whitening internally discolored teeth. You can also learn more by reading the Dear Doctor magazine article “Whitening Traumatized Teeth.”