Shade Relapse After Teeth Whitening

As dental professionals, we’ve all been asked the question, “I’ve heard that teeth whitening isn’t permanent and that if you stop your whitening treatment, your teeth will become darker again. Is this true?”

Unfortunately, there is no straightforward answer to this, which can often leave dental patients questioning whether or not teeth whitening treatment is worth it for them. Our job is to educate and encourage our patients to do what’s best for their oral health, so having a ready answer to this question will benefit both you and your patient.

What is shade relapse after whitening? Why does it happen?

Let’s start with what shade relapse is in the dental world. Put simply, shade relapse is the effect of returning to the original tooth color before whitening that a patient may experience shortly after undergoing a whitening treatment. This effect may be stronger or rather subtle, depending on what method of teeth whitening your patient is undergoing.

Here’s what’s happening—we’ll use Ultradent’s Opalescence™ teeth whitening as an example.

Opalescence whitening gels contain an active whitening ingredient—either carbamide peroxide or hydrogen peroxide. Peroxide gels break down into water, oxygen, and reactive oxygen molecules. These reactive oxygen molecules treat both the enamel and the dentin, oxidizing the bonds of discolored stain molecules. By changing the stained molecules, the tooth becomes lighter.¹

The process of whitening displaces the natural water and moisture in the enamel structure, leading to a transitory dehydration. When this displaced water returns, the tooth rehydrates. Shade relapse can occur since a dehydrated tooth can look whiter than a hydrated tooth. In other words, as the tooth rehydrates, the tooth’s natural color can darken slightly—but it should still be brighter than before the whitening treatment!

It’s important to note that not all teeth whitening treatments are equal. Opalescence gel is effective in helping reduce shade relapse as compared to competitor tooth whitening products.² You can learn more about the benefits of Opalescence™ 10% and other Opalescence teeth whitening products here.

Preventing shade relapse: Is it possible?

Technically, no. As we know it, shade relapse after a whitening treatment seems to be inevitable due to the nature of how the teeth whitening process works. Possibly, the better question for dental patients to ask is “What can I do to maintain my brighter smile for as long as possible?”

Dr. Renato Palo reminds us of the natural aging process of dentin as well. “It is normal and expected that when we get older, the dentin becomes less organic and, in turn, less clear. We cannot forget that even when we whiten our teeth, we will continue to age; therefore, it is natural that our teeth become darker over the years.”

Teeth whitening results are very stable, leaving you with a stunning smile long after your teeth whitening treatment is over. However, there are a few factors that can make teeth lose their luster. Things like genetics, age, and habits all affect your smile.

A dental patient has experienced shade relapse. Now what?

It’s almost certain that as a dental professional, you’ve worked with patients who are adamant about keeping up their new and improved smile. Assuming the dental patient has a realistic understanding and expectation of teeth whitening products, there are excellent tools we can use to help our patients retain their brighter smiles.

After an in-office teeth whitening treatment such as Opalescence™ Boost™ whitening, it’s common to send dental patients home with Opalescence Go™ prefilled trays, Opalescence™ PF whitening, or Opalescence™ Whitening Toothpaste. Which of these products you send home with your patients is most likely going to be determined by their individual situation, but all three are excellent options for maintaining a bright smile.

In summary, shade relapse can occur for a multitude of reasons for many people. The degree to how much someone experiences shade relapse after whitening can be determined by what kind of whitening treatment they chose, their genetics, their habits, and more. Luckily, Ultradent offers a lineup of products to help dental patients maintain their teeth whitening results for as long as possible.

To learn more about Opalescence teeth whitening products, please reach out to your local Ultradent Sales Representative.

1. Kwon SR, Wertz PW. Review of the Mechanism of Tooth Whitening. J Esthet Restor Dent. 2015 Sep-Oct;27(5):240-257.
2. Grobler, S.R., et al. A Clinical Study of the Effectiveness of Two Different 10% Carbamide Peroxide Bleaching Products: A 6-Month Follow-up; Int J Dent. May 5, 2011: 167525; doi: 10.1155/2011/167525.