This may be the reason behind your teeth whitening struggle.
Problem is, not all of them are good for your dentals. Some may even be staining your teeth.
According to Reader’s digest, the staining occurs because of two major ingredients: cetylpyridinium chloride (CPC), an antibacterial, and stannous fluoride, a remineralization ingredient that is found in your toothpaste.
Denist Benjamin Lawlor says, “The reason why this happens is in the way the CPC kills bacteria. CPC kills bacteria and dislodges them from the tooth. As they are being swished away, they can re-adhere to the tooth or collect in areas of the mouth—usually near the gums or on a ledge.The bacteria continue to die leaving brown stains wherever they are. Stannous fluoride can [also] stain because it has a chemical compound which includes molecules of tin. This metal can adhere to the teeth in the right conditions and cause extrinsic staining.”
When it comes to mouthwash, you’d best keep off alcohol based products as they dry up the mouth and increase the stagnant bacteria.
Luckily most companies that use the above ingredients in their products actually have a warning label on them while the others are switching it up for essential oils.