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Tooth brush question.

  1. Jul 22, 2009 #1
    I always wondered why those medics and dentists say you must change your tooth brush after months. Can somebody explain me this. Do you have to change it becouse of some bacils? If yes this leads me to two questions:
    1) Doesnt tooth paste suposed to kill bacils in my mouth and on tooth brush?
    2) Or if the evil bacils are so bad why we are'nt suposed to change tooth brush everytime we use it?

    For me its a clear lobby for toth brush industy to make people spend their money.
  2. jcsd
  3. Jul 22, 2009 #2


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    They wear down and so are less effective at brushing.

    I wouldn't have thought toothpaste kills that many.

    Bacteria aren't going to live for very long on a dry nylon toothbrush. You could rinse it in mouthwash if you are worried.

    Compared to the stuff that normally lives in your mouth I wouldn't worry.
  4. Jul 22, 2009 #3


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    The bristles get soft and flatten out. Switch to a new one and the difference will be like night & day.

    Stay with the old one and you are doing your gums a disservice.
  5. Jul 22, 2009 #4
    I aint worried about the tooth brush it self. Question is that smart people like medics and dentists do that kind of a lobby. I had all kinds of brushes: standart, electric, brush with gumm massage (i hate that one). Now i have eko brush from egypt -a root of a plant and its surprisingly good. But still my favorite brush is like 5 years old, kind find that one on a market. If here is some dentist please prove me wrong.

    ''The bristles get soft and flatten out'' good point, only my old toothbrush isnt flatten. And compered to oder ones i think its more easy to use and its better.
  6. Jul 22, 2009 #5


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    These are the reasons I've always been told. I can see that the shredding of the bristles is true.

    http://www.dentist-chicago.net/Hey-Doc-When-should-I-replace-my-toothbrush.html [Broken]
    Last edited by a moderator: May 4, 2017
  7. Jul 22, 2009 #6


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    Then you have already reached your conclusion. Why are you asking us?

    Our answer is that toothbrush bristles wear down. Claiming there's a motive in someone wanting you to change it regulary does not eliminate the undeniable fact that they do wear down, and do need to be changed for that reason alone.
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