Whitening strips are considered temporary for removing teeth stains. Most topical stains come from the foods we eat and what we drink. Therefore, as we continue to eat and drink, stains will recur, prompting treatment again. Whitening strips are considered temporary for removing teeth stains. Most topical stains come from the foods we eat and what we drink. Therefore, as we continue to eat and drink, stains will recur, prompting treatment again.