- No tooth preparation or loss of tooth structure
- In-office: a single session; at-home: 1–2 weeks
- Fillings, crowns and veneers do not whiten — the order of treatment matters
- The effect is not permanent; depending on dietary habits, refreshing is needed over time
In short: Teeth whitening is a procedure that lightens discolouration in the enamel and dentin with a peroxide-based gel, without removing tooth structure. Who it is suitable for and the method (in-office or at-home) are determined after an examination; existing fillings, crowns and veneers do not whiten with this procedure.
How does it work?
The peroxide molecule spreads into the enamel and dentin and breaks down the colour pigments accumulated there by oxidation; tooth tissue is not removed, only the discolouration within it is lightened. The result varies from person to person according to the tooth's own colour and the source of the discolouration — the response is generally more marked with external stains such as coffee, tea and smoking.
In-office or at-home?
- In-office: After the gum has been isolated, a high-concentration gel is applied under control in a single session; the result is seen on the same day.
- At-home: With thin trays made to the shape of the mouth, a low-concentration gel is used for a few hours a day or overnight for 1–2 weeks.
- Combined: An approach that starts at the clinic and continues at home with trays, using the two methods together.
Who is it suitable for, and who is it not?
- Adults with healthy gums, no active cavities and no untreated gum disease are candidates.
- It is not carried out under the age of 16, because enamel development is not complete.
- It is postponed during pregnancy and breastfeeding.
- In cases with excessive tooth sensitivity or marked gum recession, this is assessed first.
- In dark intrinsic discolouration related to tetracycline, the response may be limited; a different approach may be needed.
The process
- Examination and scaling: Gum and enamel health are assessed; whitening is not done before plaque and calculus on the teeth have been cleaned.
- Shade record: The starting shade is recorded with a standard shade guide; this is the reference point for assessing the result.
- Application: For in-office, isolation of the gum and controlled application of the gel; for at-home, taking an impression and preparing custom trays.
- Follow-up: The result and sensitivity are assessed; for at-home, the process is extended or shortened when needed.
Sensitivity
Temporary sensitivity to cold during the procedure or in the few days afterwards is a common finding; it is reduced with a desensitising gel or toothpaste. In people with a history of sensitivity, the concentration and the application time are planned accordingly.
The order with existing fillings, crowns and veneers
Whitening lightens only natural tooth tissue; it does not change the colour of composite fillings, zirconia or all-ceramic crowns, or veneers. If an aesthetic restoration is planned in the front region, whitening is completed first and, once the colour has stabilised, the restoration is made to match this final shade. Details: smile design.
Longevity and care
The effect is not permanent; staining habits such as tea, coffee, red wine and smoking darken the colour again over time. Avoiding dark-coloured food and drink for the first 48 hours protects the result. Keeping the colour light over time is supported by regular brushing and, when needed, a short refresher application.
Points to consider
- Temporary cold sensitivity lasting a few days may be seen during or after the procedure.
- If gum isolation is inadequate, the gel may touch the gum and cause temporary irritation.
- Fillings, crowns and veneers do not whiten; this is why, if an aesthetic restoration is planned, the order is determined together at the examination.
- If there are active cavities or untreated gum disease, these problems are treated first.
- The effect is not permanent; depending on diet and smoking habits, refreshing may be needed over time.
Frequently asked questions
How soon is the result seen?
With in-office whitening, at the end of a single session; with at-home whitening, a difference begins to be noticed from a few days into the application; the final result for at-home is assessed once the process is complete.
Will there be pain or sensitivity?
Pain is not expected during the procedure; temporary cold sensitivity lasting a few days is common afterwards and decreases on its own.
Will my crowns and fillings whiten too?
No. Whitening lightens only natural tooth tissue; the colour of existing restorations does not change, so a colour mismatch may occur in a visible area.
Is the result permanent?
No. Depending on staining food and smoking habits, slight darkening occurs over time; the lighter colour is maintained with regular care and an occasional refresher.
Can it be done if my gums have receded?
In cases with marked gum recession and an exposed root surface, the risk of sensitivity is higher, so this is assessed first; the decision is made by examination.
Should I choose in-office or at-home?
Both are based on the same active ingredient; the difference is in speed and concentration. The choice is determined together at the examination, according to sensitivity history and time available.
The information on this site is for general guidance only; diagnosis and treatment require an examination by a dentist.