The active ingredient in the gel that causes the whitening is carbamide peroxide. This ingredient breaks down into hydrogen peroxide, which acts as an oxygenating agent, causing oxygen to enter the enamel and dentin (the outer layers of your teeth) to break up deposits lodged in your tooth structure. This whitening acts only on the molecules that carry the discoloration and its effects will depend on the strength and duration of its contact with your teeth. The strength of this active agent is limited by safety concerns. Your tooth structure remains unchanged; only the tooth surface is made lighter. Porcelain restorations and white fillings will not usually whiten.
Brush and floss your teeth before putting in your bleaching trays.
Apply a small thin line of peroxide-based gel into each of the tooth imprints in the tray.
Do not overfill the tray!
Insert the tray into your mouth and seat the tray firmly against your teeth; be sure not to push all the gel out.
Wipe the excess material from your gum with your finger or dry toothbrush.
Try to wear the trays about two to three hours per day, or for convenience sake, you can wear the trays overnight (the gel loses 80 percent of its activity after two hours of being in your mouth).
Rinse your mouth after removing the trays and brush away any remaining gel.
Clean the tray with a toothbrush and warm water. Hot water will damage the tray; dry carefully and store in the tray holder in a cool, dry place.
Avoid eating, drinking or smoking while the whitening tray is in place.
Don't use any household or other whitening products to whiten your teeth.
Keep out of reach of children.
Keep away from direct sunlight.
Maximum results are achieved when the process is continued for 14 nights.
Avoid citrus fruits and other acidic foods while in process of bleaching. They can contribute to sensitivity by changing the acidity of your saliva and could cause damage to the outer tooth surfaces or slow down the whitening process.
Avoid tobacco, coffee, dark colas and red wines because these substances may restain your teeth.
You should avoid stain-causing beverages such as coffee, tea or cola for several days after the procedure, because your teeth may more readily absorb stain at this time.
After two to four weeks your teeth are probably bleached as much as possible.
The area of the tooth closest to the gums may take longer to whiten than the biting edge and will continue to remain the darkest part of the tooth.
Renew the whitening as needed (every three to six months). Re-apply the gel in the tray and wear the tray for two to three hours two or three times.
Daily brushing, flossing and regular dental cleanings will keep your teeth whiter!