One of the most inexpensive and easily obtainable tooth whitening systems is the whitening strip. These strips were introduced into the market in 2001.
These whitening strips have the whitener 16% carbamide peroxide pre applied by on them. Some dentists feel that the strips are good as the dose delivered is consistent and it limits the user’s exposure to gel, whereas when gel trays are used the amount of gel used can vary between each use.
There is however a large drawback with whitening strips. The whitening strips only whiten the teeth they are in direct contact with. They only whiten the front teeth. Some people find that the strips are not long enough to cover all the teeth they show when they smile. Whitening strips generally cover at least the six center teeth, eyetooth to eyetooth. A tray based system will deliver whitener to all the teeth equally.
The strips are invisible. One manufacturer instructs you wear the strip thirty minutes twice a day. They claim you will see a difference within three days and full results within seven days. They also claim the whitening effect will last up to eighteen months.
Most dentists see no harm done...