If you want whiter teeth and a tooth gem, whiten first, wait about two weeks, then have the gem placed. A tooth gem is a small crystal bonded to the front of a tooth with resin, and teeth whitening gel cannot properly reach the enamel under it or lighten the resin around its edge. Timing matters for the bond too: in one laboratory study, brackets bonded a day after a strong hydrogen peroxide treatment held at about half the strength of brackets on unbleached enamel, and were back near normal by 14 days.
Written by Dr James Tran, BDent (University of Sydney), MICOI, GradDip (Oral Implants), general dentist at Lumi Dental in Melrose Park.
The short version
- Whitening gel lightens natural enamel. It does not change the gem, the resin holding it, or crowns, veneers and bonding.
- The simple rule: whiten first, wait about two weeks, then place the gem.
- A gem left on during whitening usually leaves a small patch beneath it that lightens less. You may only notice it when the gem comes off.
- Take-home trays need room around a gem, so mention it before your trays are made.
- A gem should be removed in a dental chair, not with tweezers. Our guide to tooth gem safety covers placement, plaque and removal.
- A gem on a crown, veneer or bonding sits on a surface that will not whiten at all.
How a tooth gem is held on
A flat-backed crystal, often less than 2 mm across, is attached with the same kind of bonding used for tooth-coloured fillings and orthodontic brackets. A case report from a dental hospital describes the steps: the enamel is etched with phosphoric acid, an adhesive is applied, a drop of flowable composite resin goes on the back of the gem, and the resin is set with a curing light. Gems are usually placed on upper front teeth and canines, and the thin rim of resin around them behaves like a white filling, not like enamel.
The simple rule: whiten first, then place the gem
If you do not have a gem yet, whiten first, wait about two weeks, and then have the gem bonded. If you already have one, decide first whether it stays.
Why the wait helps the bond
Peroxide leaves oxygen in the enamel for a while after whitening, and that can interfere with resin bonding. In a laboratory study by de Almeida and colleagues, brackets bonded one day after bleaching with 35% hydrogen peroxide had a bond strength of about 15.5 MPa, against about 30 MPa on unbleached enamel. At one week it was still lower than normal; at 14 days it was close to the unbleached group. Other researchers have found little or no reduction, and this study used cattle teeth, so treat two weeks as a sensible margin rather than a precise rule.
The shade also needs to settle
Teeth can look brightest straight after a session, partly because the enamel dries out a little. A small randomised trial comparing home trays with an in-chair session measured colour from two weeks to six months and found the colour drifted back faster after the in-chair treatment. Placing a gem once the shade has settled sets it against the colour you will live with. I usually suggest a quick shade photo at the two-week mark before the gem is booked.
What happens to the enamel under a gem
Whitening gel soaks into the enamel and breaks down coloured molecules in the dentine underneath. Where the gel cannot sit, the tooth gets less of it. The enamel under a gem is covered, so that small circle is likely to lighten less than the enamel around it. Peroxide does spread a little sideways through the tooth, so on some teeth the difference is hard to see, and on others it shows as a slightly darker dot once the gem is gone.
While the gem is on, the patch is hidden. A short top-up course after removal can sometimes bring that spot closer to the rest of the tooth, but it may not match completely.
The resin rim does not whiten
Teeth.org.au, the consumer site of the Australian Dental Association, notes that whitening gel only lightens enamel and will not change the colour of composite resin. The resin skirt around a gem can pick up stain and keeps that colour while the enamel beside it lightens. A dark ring around a gem after whitening is usually this resin, not the tooth.
Gems placed over white spots
Some people choose a gem to cover a chalky white mark, and the hospital case report used gems for exactly that. Whitening can make white spots look more obvious for a while, as our article on white spots after whitening explains, so mention it if your gem is hiding one.
Take-home trays with a gem on the tooth
Custom trays fit closely so the gel stays on the teeth and off the gums. Our article on how custom whitening trays work explains the fit in general.
- Mention the gem before the scan, so the tray can be made with a little space around it.
- A tray that presses on the gem can loosen it, rub the lip, or stop the tray seating fully.
- Gel tends to pool beside a gem. Use only the amount you are shown and wipe away any excess.
In-chair whitening with a gem on the tooth
In-chair whitening uses a much stronger hydrogen peroxide gel, a cheek retractor and a protective barrier over the gums. Teeth.org.au warns that strong gel can cause chemical burns if it touches the gums, lips or tongue. Our article on what to expect at in-chair whitening walks through the visit.
With a gem in place, the dentist may cover it with a little barrier material so gel does not sit on the resin rim. The covered patch will not lighten much. In my experience, people who plan to keep their gem for years are comfortable with that, while people who expect to remove it soon are often better off taking it off first so the whole surface whitens together.
Removing a gem before whitening
Enamel does not grow back, so how a gem comes off matters. In the case report, the gem was lifted with an ultrasonic scaler and the leftover resin was cleaned away with a slow-speed finishing bur. The bond gave way between the gem and the resin, leaving the enamel largely intact. Prising a gem off at home with a fingernail or tweezers is far more likely to scratch or chip the surface.
Once the gem is off, the enamel is polished and checked, and whitening can start. If you want a gem again afterwards, the same two-week wait applies.
Gems on crowns, veneers or bonding
Porcelain crowns, veneers and composite bonding do not whiten. If your gem sits on one of these, whitening lightens the natural teeth around it but not the restored tooth, which can end up looking darker than its neighbours. Our article on whitening with fillings or bonding explains how composite is usually matched afterwards.
| Situation | What to do first | What to expect with the shade |
|---|---|---|
| No gem yet | Whiten, wait about two weeks, then place the gem | The gem sits on enamel at its settled, whiter shade |
| Gem already on and staying | Whiten around it, with tray space or a barrier over the gem | The patch under the gem likely stays nearer the old shade, hidden while the gem is on |
| Gem coming off | Have it removed and polished, then whiten | The whole surface can whiten evenly |
| Gem on a crown, veneer or bonding | Have the restoration checked first | The restored tooth does not whiten, so neighbouring teeth may end up lighter |
How we approach this at Lumi Dental
Whitening at Lumi Dental starts with an examination by the dentist, who checks the gem tooth for decay or plaque at the resin edge, looks for any white spot the gem might be covering, and notes any crowns, veneers or bonding. Lumi Dental does not list cosmetic tooth gems among its services, so the team's part is the whitening plan and advice on timing if you plan to have a gem placed afterwards; if a gem needs to come off first, removal can be discussed at the consult. Trays are made from an in-house 3D intraoral scan, described on our technology page, and the whitening options are named Lumi Home, Lumi Refresh and Lumi Radiance.
Questions patients ask
Should I whiten my teeth before or after getting a tooth gem?
Before. Whiten first, then wait about two weeks so the shade can settle and the enamel can recover its bonding strength.
Will the tooth under my gem be a different colour after whitening?
It may be. The enamel under the gem is covered, so it tends to lighten less than the rest of the tooth. The difference varies and stays hidden while the gem is on.
Can I use whitening strips with a tooth gem?
It is not ideal. Strips sit flat against the teeth, bridge over the gem and can leave the area around it unevenly lightened. Custom trays can be made to allow for the gem.
Can I take my tooth gem off myself?
It is better not to. Prising a gem off can scratch or chip enamel, which does not grow back. A dentist can lift the gem, clean off the resin and polish the surface.
How long after whitening can I get a tooth gem?
About two weeks is a sensible gap. Laboratory work on brackets found bond strength was still reduced a week after a strong in-chair gel and close to normal at 14 days. A complimentary cosmetic consult is a good place to plan the timing.
Thinking about whitening? Complimentary cosmetic consult in Melrose Park
If you have a tooth gem, or are planning one, the team at Lumi Dental can check the tooth, plan whitening around it and suggest when the gem should go on. Book a complimentary cosmetic consult at Melrose Central in Melrose Park, or read more about teeth whitening at Lumi Dental. Patients visit from Ryde, Parramatta, Ermington and Rydalmere, with on-site parking.
Sources
- Australian Dental Association (teeth.org.au): Teeth whitening
- PMC: Influence of delay between dental bleaching with 35% hydrogen peroxide and orthodontic brackets on the bond strength at the enamel/adhesive interface
- PMC: Non-destructive management of white spot lesions by using tooth jewelry
- PMC: The degree of color change, rebound effect and sensitivity of bleached teeth with at-home and power bleaching techniques
About the author
Dr James Tran is a general dentist at Lumi Dental in Melrose Park. He holds a BDent from the University of Sydney and a Graduate Diploma in Oral Implants, and is a Member of the International Congress of Oral Implantologists (MICOI).
This article is general information only and is not a substitute for an examination and individual advice from a registered dental practitioner. Suitability for any treatment varies from person to person.
