In-office teeth whitening is not an altogether complicated procedure, but it does require skill to avoid injury to the gingival (gum) area. Moreover, expensive equipment may be needed to prepare and finish the procedure. All told, the procedure can take anywhere from 60 to 90 minutes to complete.

There are several standard steps to performing an in-office whitening:

Before starting, the dentist will make a record of the current shade of your teeth.

Your teeth would then be polished with pumice, a grainy material used to remove any plaque on the surface.

Your mouth will be isolated with gauze to keep your teeth dry. Retractors may be used to keep your cheeks, lips, and tongue well away from the whitening solution.

A barrier would next be placed along the gumline to further protect it from exposure to the solution.

Next, the teeth would be coated with a whitening solution on the front surface only. The solution typically includes either hydrogen peroxide or carbamide peroxide as the bleaching agent.

Many whitening products require a curing light or laser to activate the peroxide. Once applied, the solution would be left on the teeth for 30 to 60 minutes, or reapplied occasionally, depending on the brand.

Once the optimum shade has been reached (or the maximum time has passed), the teeth would be rinsed. A fluoride application may be used to help ease any tooth sensitivity.

Additional visits would be scheduled until the desired shade is reached.

Upon completion, you would be advised to avoid foods or beverages with a high level of pigment for at least 24 hours. These include coffee, tea, tomato sauce, tomato juice, yellow mustard, beets, black grapes, candies, and red wine. Smoking or tobacco of any sort would also be avoided.