what is the reason that we must brush our teeth every day?

Now How Many times per day that yourself Brushes your own teeth as to keep them clean also healthy ? this is asked by the American Dental Association and the general Health Care ?
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Because otherwise bacteria have a field day in your filthy mouth. They eat away your teeth, your gums, and if things get bad enough, the infection can spread to your blood and you can get septic. Brush at least twice a day. Floss if you're smart.
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