You can often whiten teeth that have some enamel erosion, but the result is usually smaller than people expect and the erosion needs to be stopped first. Erosion thins the enamel, so more of the yellow dentine underneath shows through, and whitening gel lightens that dentine only part of the way. Teeth with exposed dentine also tend to feel whitening more, so the gel strength and wear time usually need adjusting.
Why eroded teeth look more yellow
Enamel is slightly translucent and close to white. Dentine, the layer beneath it, is naturally yellow to light brown. On a healthy tooth the enamel is thick enough to soften that colour. When acid dissolves the enamel over months or years, the layer gets thinner and the dentine colour comes through more strongly. The tooth can look yellow in the middle and see-through or grey at the biting edge, where there was never much dentine to begin with.
This is different from staining. Coffee, tea and red wine leave pigment on and within the enamel, which whitening is good at breaking down. Erosion changes how much enamel is there at all. The common sources are acidic drinks sipped through the day, reflux, frequent vomiting, and habits such as lemon water or holding sports drinks in the mouth. Our guide to enamel erosion causes and prevention covers these in more detail, and acid reflux and your teeth explains why erosion from reflux tends to show on the inner surfaces first.
What whitening can and cannot change
Peroxide gel passes through the enamel and breaks down the coloured molecules inside both enamel and dentine. That means it can lighten an eroded tooth to some degree, because the dentine itself becomes paler. What it cannot do is put back the enamel that has gone. The tooth will still have less of the white, light-scattering layer that makes a smile look bright, so a tooth with heavy erosion may only lift a little.
The see-through edges are worth knowing about before you start. Whitening does not make enamel more translucent, but as the body of the tooth gets lighter, a thin grey edge can stand out more by contrast. People sometimes read this as whitening having damaged the tooth when it was there all along. Our article on translucent teeth explains why edges look this way.
Does whitening make erosion worse?
At the strengths dentists use and when used as directed, the research does not show whitening adding meaningful enamel loss on its own. Some gels are more acidic than others, though, and an eroded tooth has less margin to spare. The bigger practical issue is comfort. Where enamel is thin or worn through, the dentine has open tubules that run toward the nerve, and peroxide reaching the nerve is what causes the short, sharp twinges people describe. More of that path is open on an eroded tooth.
For that reason a dentist will usually lean toward a gentler plan: a lower concentration gel in custom trays, shorter wear times, and nights off when the teeth feel sore.
Stop the erosion before you whiten
Whitening a tooth that is still being worn away by acid tends to give a short-lived, patchy result. The first step is working out where the acid is coming from and reducing it. In practice that usually means a few changes.
- Keep acidic drinks to meal times rather than sipping them across the day.
- Rinse with water after acidic food or drink and wait about 30 to 60 minutes before brushing.
- Use a soft brush and a fluoride toothpaste, and spit rather than rinse after brushing.
- See your GP if reflux or regular vomiting is the likely cause, since that needs treating in its own right.
A check-up at this stage lets a dentist grade how much enamel is left, look for exposed dentine near the gums, and check for cavities or leaking fillings that would make whitening uncomfortable. That is part of a routine visit with our general dentistry team.
How whitening is usually planned for eroded teeth
The plan depends on how much enamel is left. Mild erosion, where the surface looks smooth and slightly glassy but the shape is intact, often responds reasonably well to take-home whitening at a lower strength. Moderate erosion, with cupped-out areas on the chewing surfaces or thin edges, may whiten a little but often needs some rebuilding as well. Severe erosion, where teeth have lost length or shape, usually needs restorative work, and whitening becomes a step to set the colour before that work is matched.
| Amount of erosion | What whitening may do | What is often added |
|---|---|---|
| Mild, surface looks smooth and glassy | A modest lift, usually with lower strength gel | Fluoride or remineralising paste, diet changes |
| Moderate, thin edges or small hollows | A small lift, edges may still look grey | Composite bonding to cover exposed dentine and edges |
| Severe, teeth shorter or reshaped | Little visible change on its own | Bonding, veneers or crowns, planned after the colour is set |
If bonding or veneers are part of the plan, the usual order is to whiten first, let the colour settle for about two weeks, then match the new material to the whitened teeth. Bonding can protect exposed dentine and rebuild thin edges with very little drilling, which is covered on our composite bonding page. Our teeth whitening page explains the take-home and in-chair options, and we can talk through whether whitening alone, bonding, or both would suit your teeth at a free consult. For current options, see our current deals.
Questions we are often asked
Will whitening strengthen my enamel?
No. Whitening changes colour, not structure. Fluoride toothpaste and remineralising pastes containing calcium and phosphate can help harden the surface of the enamel that is left, but neither grows new enamel.
Is whitening toothpaste safe if I have erosion?
Many whitening toothpastes work by abrasion, which can wear softened enamel faster. If you have erosion, a low-abrasion fluoride toothpaste is usually the better daily choice, and any whitening is best done with gel in trays.
Can whitening gel cause erosion?
A review by Demarco FF and colleagues in Clinical, Cosmetic and Investigational Dentistry (2011) found that hydrogen and carbamide peroxide gels did not cause clinically significant mineral loss from erosion or abrasion, while noting that most of the studies that did find surface changes were done in the laboratory. Some gels sit below the pH at which enamel starts to dissolve, which is one reason dentists choose the product carefully for eroded teeth.
Why do my teeth hurt more than my friend's did during whitening?
Sensitivity is the most common side effect of whitening, and Haywood VB and colleagues (JADA, 1994) found it was generally mild and settled after treatment. Thin enamel and exposed dentine make it more likely. Our guide to whether teeth whitening hurts lists steps that can help.
