Internal Tooth Bleaching: What You Need to Know
Pros & cons
How much it costs
If it works on dead teeth
What to expect
Whether it's painful
How long results last
Fast facts
Internal tooth bleaching whitens teeth from the inside out. (It's also known as non-vital bleaching.) Usually, this teeth whitening procedure is done on a dead tooth thatâs previously had a root canal, an endodontic procedure that removes the soft inner core of dental pulp chamber.Â
After a root canal, a tooth can become discolored or develop intrinsic dark or yellow stains. Internal bleaching can remove discoloration from a dark tooth and restore its natural tooth color.Â
Because the bleach is left in the tooth for several days to weeks, the technique is often referred to as a âwalking bleach.â
This whitening technique can be very effective. âIâve seen amazing results from internal bleaching following root canal treatment,â says Dr. Steven Davidowitz, a leading cosmetic dentist in New York City.
In one study where internal bleaching was done on 255 teeth in 203 patients, researchers reported that all teeth had either âgoodâ or âacceptableâ color change, and there were no cases that were considered to have had no change at all. All of the gray cases and almost all the light yellow and black cases had âgoodâ outcomes. The dark yellow teeth were harder to bleach, and about oneâthird of this group had only âacceptableâ changes rather than âgoodâ changes. However, overall, the results of the bleaching were very encouraging and predictable.
The procedure can also be redone, if sufficient whitening doesnât occur the first time.Â
Pros
- The treatment is safe and provides predictable whitening results, even on a dead, dark tooth.Â
- Internal bleaching is inexpensive and simple to perform. The procedure takes only a few minutes and doesnât require anesthesia.Â
- Unlike veneers, crowns, or implants, internal bleaching conserves the tooth structure, so it shouldnât weaken the treated tooth.
Cons
- It may take repeated treatments to see the color change youâre looking for.Â
- The bleached tooth may initially look a little whiter than your other teeth post-treatment, âbut it always settles down to match the other teeth,â says Dr. Wendy Spektor, a dentist in Bellevue, Washington.
- Results last about a year, so you can expect to need maintenance treatments.
The price you pay will depend on the experience level of your provider, their practice location, and whether you need more than one treatment for your desired result.
Yes, internal bleaching is actually the best way to whiten a dead tooth that has previously undergone root canal therapy.
First, your endodontist or cosmetic dentist will take X-rays to assess your particular case. The process generally requires only the drilling of a small access hole in the back of the tooth, usually where the original root canal entered the pulp.Â
Your dentist inserts the bleaching material, covered with a cotton pellet, and then seals it with a temporary adhesive. A putty of sodium perborate, which is more easily controlled and safer for this purpose than hydrogen peroxide or other external bleaching agents, is usually used.Â
The bleaching agent is left in the tooth for several days or longer. Depending on the severity of the discolored tooth, the procedure may be repeated several times, to achieve the desired whiteness. (Typically, the goal is to match it to adjacent teeth.)
After the final treatment is complete, the empty space inside the tooth is cleaned, and the missing tooth structure is replaced with a root canal filling made of composite resin, a tooth-colored filling material. That seals the dentin. This blocks any translucent spots, so the tooth doesnât look hollow, and adds bulk to the tooth, which can weaken and fracture if itâs not filled in.
Dentophobes can relax: thereâs no discomfort during the whitening treatment. The nerves of the tooth were removed during root canal therapy, so you wonât feel anything during internal bleaching.
Updated June 13, 2023