When ds1 was 3, it was twice a day (not hardcore though- we did skip sometimes). I've read that after 12hours, the bacteria on your teeth are worm shaped (and apparently can do more damage). I'll see if I can find the link.<br><br><a class="bbcode_url" href="http://www.zelliescleanwhiteteeth.com/Zellie-Mouth-Care-System.aspx" target="_blank">Here it is</a>:
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<div class="quote-block">Brushing every 12 hours is important because bacteria that grown on teeth become tubular or worm-like after this amount of time. These harmful bacteria grow and multiply in the deeper layers closest to the tooth. More germs attach on the outside, forming a barrier that cuts off oxygen, causing germs to change and become anaerobic. At this point they become damaging cavity-forming bacteria that take minerals out of teeth and inflame gums.</div>
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