Two professional routes
Beyond whitening toothpaste and strips, dentists offer two main options: in-chair (in-office) whitening and custom take-home trays. Both use professional-strength peroxide gels that are stronger and more even than anything you buy off the shelf, and both start with a quick check that your teeth and gums are healthy enough to whiten.
In-chair whitening
Done in a single appointment of about an hour, in-chair whitening uses a high-concentration gel, often with a light. You walk out several shades brighter the same day. It is the fastest route and great before an event, but it tends to cost more and can cause short-term sensitivity. Typical cost in Canada is roughly CA$300 to CA$800.
Custom take-home trays
The clinic takes impressions and makes trays moulded to your teeth, then gives you gel to wear a little each day for one to two weeks. Results build gradually and are easy to top up later with the same trays. It is gentler on sensitivity and usually cheaper — roughly CA$200 to CA$500 — but it takes patience. Many patients combine the two: an in-chair kickstart plus trays for maintenance.
What to keep in mind
Whitening lifts stains on natural enamel — it does not change the colour of crowns, veneers or fillings, so those may need replacing to match. Sensitivity is common and temporary. And whitening works best on a clean mouth, so a cleaning first often gives a better result.