In-office whitening — what to expect & how to care for your teeth afterwards
In-office whitening is one of the fastest ways to brighten your smile — and when done correctly, it's safe and effective. Here's everything you need to know before and after your appointment.
Before your appointment
Ensure your teeth and gums are healthy before whitening — your dentist will advise you if whitening is suitable for you
Brush your teeth before your appointment
Let your dentist know if you have a history of sensitive teeth — we can take extra precautions to keep you comfortable
Whitening does not work on crowns, veneers, fillings, or other restorations — these will remain their original colour while your natural teeth whiten. Discuss this with your dentist beforehand if relevant
You may take analgesics 1 hour before your appointment - this will help with the sensitivity.
During the appointment
A protective barrier will be placed over your gums before the whitening gel is applied — this is to protect your gum tissue from the bleaching agent
The whitening gel is applied to your teeth and activated — the process typically takes 60- 90 minutes depending on the system used
You may experience some sensitivity or a tingling sensation during the procedure — this is normal. Let your dentist know if you are uncomfortable at any point
Avoid swallowing the gel — it is harmless in small amounts but is not meant to be swallowed
After your appointment — the first 48 hours
The first 48 hours after whitening are the most critical — your teeth are more porous during this time and highly susceptible to staining. Please follow the white diet strictly during this period:
✅ What you can eat and drink:
Plain water
White rice, pasta, and bread
White fish and chicken (no marinades or sauces)
Eggs
Milk, white cheese, and yoghurt
Bananas and other light-coloured fruits
Clear or white soups
❌ What to avoid for at least 48 hours:
Coffee, tea, and all coloured beverages including soft drinks and juices
Red wine
Soy sauce, curry, tomato-based sauces
Coloured fruits such as berries, grapes, and pomegranate
Beetroot, carrots, and other richly coloured vegetables
Coloured sweets and candy
Smoking and tobacco products
Managing sensitivity
Some sensitivity after whitening is completely normal and typically resolves within 24–48 hours
Use a sensitive toothpaste for the days following your appointment
Avoid very hot or very cold food and drinks if you are experiencing sensitivity
Take over-the-counter pain relief such as paracetamol if needed
Contact your dentist if sensitivity is severe or persists beyond 48 hours
Maintaining your results
Avoid staining foods and beverages as much as possible going forward
When drinking coloured beverages, use a straw to minimise contact with teeth
Brush twice daily and maintain good oral hygiene
Consider a take-home whitening kit for periodic top-ups to maintain your results
Results typically last 6 months to 2 years depending on diet and oral hygiene habits
Schedule regular dental cleanings to remove surface stains
💡 Dr Watt's tip: Think of the 48 hours after whitening like a freshly painted wall — anything that can stain a white shirt can stain your teeth during this window. When in doubt, leave it out! 😊
