Why don’t composite fillings or crowns get whiter?
The whitening agent brightens teeth by breaking down pigment molecules inside the tooth, but resin, porcelain, and zirconia are not tooth tissue, so the agent does not act on them. If an old filling has turned yellow, that part stays the same even after whitening.
In fact, the brighter the natural teeth get, the bigger the difference from the filled spot. When people say “I had whitening, but the spot is still there,” this is the case: it is not that there was not enough agent, but that the material does not respond to it.
| Where the color is | Whitening effect | Next treatment |
|---|---|---|
| Surface stains (coffee, tea, tobacco) | Come off well | Remove first with scaling and stain removal |
| Color inside the tooth (dentin) | Gets brighter | Whitening |
| Composite filling | Does not change | Refill after whitening |
| Crowns and porcelain veneers | Does not change | Remake if needed |
| A single tooth that has had root canal treatment | Surface whitening is not enough | Non-vital tooth whitening (for a tooth that has had root canal treatment) |
If only one front tooth is dark, will whitening fix it?
If only one front tooth is dark, the cause is often inside the tooth, so whitening all the teeth will not solve it. A tooth whose nerve died after an impact or that has had root canal treatment turns gray or brown from the inside. Whitening all the teeth in this case only brightens the other teeth and makes the difference bigger.
For such a tooth, we brighten only that one tooth from the inside with non-vital tooth whitening, cover it with a porcelain veneer or crown, or re-examine the nerve-related problem. Treatments by cause of front tooth discoloration can be found on the Front tooth treatment page.
Which should come first, whitening or composite fillings?
Whitening is done first, and once the color has settled, the composite fillings are rematched. If you get new composite fillings first and then whitening, the brightened teeth and the new fillings will no longer match again.
- Surface stains are removed with scaling and stain removal.
- The natural teeth are brightened with whitening.
- We usually wait 1–2 weeks for the color to stabilize.
- Noticeable composite fillings are redone to match the new tooth color.
If the entire front surface is covered with resin or there are old restorations, instead of whitening we look at removing that layer and remaking it, or placing Brinate. The agent only works on the tooth under that layer.
How are composite fillings and crowns checked before whitening?
We start by counting how many composite fillings and restorations there are on the front teeth, and whether they are in positions visible when you smile. Composite fillings on molars that are not visible when smiling are often left as they are even if the color differs. On the other hand, for composite fillings on front teeth, it is a good idea to plan ahead for the schedule and cost of rematching them after whitening.
Stains on the surface of a composite filling can improve a little with scaling or polishing, but a color change in the material itself does not reverse. The same goes for crowns: the color inside porcelain does not change with whitening or polishing. That is why, in the whitening consultation, we decide together which restorations to leave as they are and which to redo.
How we do it at Wonjin Dental
Before whitening, I first sort out where the color is. The order and treatment depend on whether it is a surface stain, color inside the tooth, or the color of a filling material. Prices related to teeth whitening are as follows.
| Treatment | Price |
|---|---|
| Stain removal | ₩100,000 |
| Professional whitening, 1 session | ₩110,000 |
| Professional whitening, 3 sessions | ₩330,000 |
| At-home whitening (tray + gel), per arch | ₩250,000 |
| Non-vital tooth whitening (touch-up included) | ₩100,000 |
As of September 2026, cosmetic treatment (whitening) items include VAT. All prices can be found on All treatment fees.
Frequently asked questions
Can whitening match my teeth to my crowns?
If your natural teeth are darker than the crown, whitening can reduce the difference. Conversely, if the crown is darker, whitening cannot match them and the crown has to be remade.
Is it okay to whiten teeth that have composite fillings?
In most cases, yes. However, if there is a gap or a cavity at the edge of the filling, the agent can seep in and cause sensitivity, so we check beforehand.
How long do whitening results last?
It depends on diet and care, and the color gradually returns over time. How long it lasts is summarized in How long does whitening last?.
