Internal Bleaching

Internal bleaching lightens a single tooth that has gone dark from the inside, usually after a root canal or an old injury. Whitening gel is placed inside the tooth through the root canal opening, sealed in, and changed every few days until the shade matches its neighbors. At Pearl32 Dentistry and Wellness in Laguna Hills it takes one to three visits, usually with no numbing.

The short answer

If one front tooth is darker than the rest and it has had a root canal or a knock in the past, internal bleaching is usually the first thing to try. It keeps the tooth as it is, costs less than a veneer or crown, and can be repeated. If the tooth is heavily filled or cracked, a crown or veneer is the better fix, and we say so.

Why one tooth goes dark

A living tooth has a nerve and blood supply inside it. When that dies, after a deep filling, a fall or a root canal, blood pigments and tissue breakdown products soak into the dentin from the inside. The enamel over it is unchanged, so the tooth looks gray or brown through a clear shell. Whitening from the outside works on enamel and barely reaches this kind of stain.

How it works at our Laguna Hills office

First we check the root canal on an x-ray. The bleaching only goes ahead if the root filling is sound and well sealed, because the gel must not reach the root. If the root canal is old or leaking, it is redone first by our endodontic team. Then the filling at the back of the tooth is opened, the root filling is sealed off with a protective barrier, and whitening gel is placed in the crown of the tooth and closed with a temporary filling. You come back in a week or so and we change the gel. When the shade matches, the tooth is cleaned out and filled permanently with a tooth-colored resin.

What internal bleaching will not do

It will not lighten the teeth either side, so if the whole smile needs brightening we whiten everything first, then bring the dark tooth up to the new shade. It will not fix a crack or a heavily filled tooth, which needs a crown. And the result can fade over years, though it can be repeated. Root resorption after internal bleaching has been reported in the past with older methods; the protective barrier over the root filling is how modern technique guards against it.

Alternatives

A porcelain veneer covers the front of the tooth and gives a lasting, exact color match, at the cost of some enamel. A crown does the same for a tooth that is heavily filled. Bonding can mask a dark tooth in one visit but is thin and tends to look opaque. For everyday yellowing across all your teeth, see our teeth whitening options.

Cost

Internal bleaching is quoted per tooth, itemized and in writing, after an examination and x-ray. It costs less than a veneer or crown on the same tooth. Dental plans do not normally cover it. Third party financing is available through the plans on our financing page, and the practice is not the creditor.

Questions people ask about internal bleaching

Why did my tooth turn dark after a root canal?

When the nerve inside a tooth dies or is removed, blood pigments and breakdown products soak into the dentin from the inside. The enamel is fine, but the tooth looks gray or brown. Whitening from the outside barely reaches it, which is why internal bleaching places the gel inside the tooth.

Does internal bleaching hurt?

No numbing is usually needed, because the nerve has already been removed. You may feel pressure while the old filling is opened and the gel is placed. Between visits the tooth is sealed, so there is nothing to feel. Most people describe it as one of the easier dental visits.

How many visits does internal bleaching take?

Usually one to three visits, one to two weeks apart. The gel is sealed inside the tooth and changed at each visit until the shade matches its neighbors. Once it does, the opening is filled permanently. The whole course is normally finished inside a month.

Will the new color last?

Often for years, but the tooth can drift darker again over time. If it does, the bleaching can be repeated. Some people choose a veneer or a crown later for a longer-lasting match. We tell you which is more likely for your tooth after looking at how dark it is and how much tooth is left.

What if the tooth does not match after bleaching?

Most single dark teeth lighten well. A few stop short of a perfect match, usually when the stain is very old or the tooth is heavily filled. In that case a porcelain veneer or a crown gives the color you want, and the bleaching has still made the porcelain easier to match. We say which is likely before we start.

This page is general information, not a diagnosis. What is right for you can only be decided after an examination.