Internal tooth bleaching is a whitening treatment that lightens the tooth from the inside out. The technique is usually performed on teeth with a previous tooth canal.

This procedure can remove discoloration and improve the grey appearance that often occurs in these “dead” teeth. The deteriorating pulp in decaying teeth may cause internal discoloration. It is essential to remove the cause of the change with a root canal before addressing the tooth's color. The bleaching process can follow after the treatment is complete. In severe cases, dentists may recommend tooth bleaching followed by veneers for a better appearance.

After the bleaching material is placed inside the tooth, it’s left for a few days to several weeks to take effect. Patients see improvements in grey and light yellow stains, but darker discoloration may be more challenging.

They should not feel any discomfort during the process, and dentists can repeat the treatment multiple times to reach the desired results.

The internal tooth bleaching treatment begins by creating a tiny hole through the back of the tooth. This is usually the same place where the root canal system was accessed for initial treatment. Dentists insert the bleaching agent, usually sodium perborate, into the hole and cover it with a cotton pellet and adhesive. They leave the material in place for several days 
and often replenish with fresh material every few days.

Once the patient has achieved their desired results, the dentist fills the hole using a tooth-colored composite resin. Internal tooth bleaching is not recommended for patients under the age of 19. It’s also important to note that this procedure cannot address discoloration caused by metallic debris or restorations.