When you meet anyone for the first time, among the first things that catches your attention is their smile. This is why a good number of people with discolored teeth have at some point or other contemplated buying a whitening strip to get rid of the starkly uneven coloration. But whitening strips have been known to sometimes exacerbate white spots, which is why taking time to understand how the strips work is important.

Almost all teeth whitening strips that are available over the counter rely on a peroxide base to bleach teeth. The type of peroxide used may vary slightly but by far the most popular use carbamide peroxide. The next most widely used is hydrogen peroxide.

There is some science at the back of the whitening process. White spots and teeth stains in general are in fact the result of molecules that have as a result of decay, trauma or hypocalcification, bonded with the tooth’s outer surface.

The active peroxide ingredients of the whitening strip kick into action once the strip is placed on the affected tooth by permeating the surface of the tooth before attacking and breaking down these molecules. The result is lighter colored teeth.

Because virtually all tooth whitening strips contain peroxide in some form or other, how does one determine the effectiveness of one whitening strip over another? The distinction is in the strength or concentration of peroxide concentration.

Majority of over the counter strips have formulas whose concentration is anywhere between 10% and 22%. Whitening strips used at dentists’ offices are often stronger than can be purchased over the counter with concentration as much as 35%.

So where do the white spots from the whitening strips come from? First, remember that the peroxide compound that is the key ingredient used, is some form of acid. If the enamel of the teeth is weakened or substantially worn away, this acidic compound can lead to further deterioration.

The result in the emergence of white spots even in areas that were not originally affected or bring to prominence white spots that were not initially visible to the naked eye. This is why a dentist’s advice is important before using any teeth whitening strip since such spots may only worsen with further use of whitening strips.

That being said, white spots may also appear to become whiter when whitening strips are used the first time even if the enamel is strong. This is normal and the difference in color between the white spot and the rest of the tooth will gradually reduce after several strip whitening sessions.