Choosing between the whitening options
All tooth whitening uses the same active ingredient — peroxide. The differences are concentration, how long it sits on the tooth, and whether anyone is protecting your gums while it does. That is what separates a one-hour in-office session from a two-week tray course from a supermarket strip.
The three routes, compared honestly
- In-office (Zoom). Strongest gel, highest supervision, biggest change in one visit. Best when you have a date to be ready for. Most likely of the three to cause short-term sensitivity.
- Custom take-home trays. Trays moulded to your teeth, with gel you wear for a set time over one to two weeks. Reaches a similar end point more gradually, is gentler on sensitive teeth, and the trays are reusable for top-ups afterwards. For most people this is the best value.
- Over-the-counter strips and pens. Weakest, and they do not follow the shape of your teeth, so results are patchy at the edges and the gel tends to reach the gum. They do something. They will not do what the other two do.
A common plan is both: an in-office session to get the shade down quickly, then trays to maintain it. There is a longer comparison here: professional vs. at-home whitening.
Why we check before we whiten
Peroxide moves through enamel into the tooth. If there is decay, a leaking filling, an exposed root surface or inflamed gums, that is a route to real pain rather than a whiter smile. A short exam first is not a sales step — it is the difference between a comfortable result and a miserable week. If whitening is not the right treatment for your discoloration, we will tell you that too.
What whitening cannot change
Crowns, veneers, bonding and tooth-coloured fillings do not whiten. Whiten first, wait about two weeks for the shade to stabilise, then match any new dental work to it — otherwise your restorations will be the wrong shade in one direction or the other. Grey and tetracycline staining respond slowly and sometimes only partially, and veneers are the more predictable answer for those.
Sensitivity, and how to reduce it
Brief cold zings for a day or two are the usual experience, and they are temporary. A desensitising toothpaste for the week before, a fluoride treatment afterwards, and spreading the gel over more days rather than fewer all help. If you already have sensitive teeth, trays over a longer period are usually the more comfortable route — more here: whitening with sensitive teeth.
Making it last
Expect one to three years, depending mostly on coffee, tea, red wine and tobacco. Rinsing with water after staining drinks, and occasional top-up nights with your trays, keep the result going with far less effort than starting over. Full detail: how long does teeth whitening last?
