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Crest White Strips

  1. Jun 16, 2008 #1
    First of all the chemistry behind crest white strips, do they actually work?

    I have a package of Crest White Strips Premium plus my friend gave me from his work they have expired are they still effective after expiration date?
  2. jcsd
  3. Jun 16, 2008 #2


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    Staff: Mentor

    Check what active ingredient is - that's answer to both your questions :wink:

    Hydrogen peroxide is a strong oxidizer - so it may work. It is also unstable - so they can be not effective after expiration date, or at least less effective.
    Last edited by a moderator: Aug 13, 2013
  4. Sep 1, 2008 #3
    I would not use it after the expiration date.
  5. Sep 2, 2008 #4


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    Homework Helper

    Hydrogen peroxide decomposes at a fast rate in water, I would still use the product since these strips have Hydrogen Peroxide imbedded in something other than water, however they may not be a great as one which has not exceeded the expiration date. Observe the package , if it seems inflated , than it's probably no good.
  6. Jan 10, 2012 #5
    My mother swears by them, they definitely work... within the expiration date, at least.
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