Ok, so how should I brush my teeth?
Well, you need to pay particular attention to all the red and swollen areas of the gums.
But when I brush them they start to bleed!
That’s why you need to brush them! I know it sounds counter intuitive, but there is plaque on and around your teeth and calculus or hard plaque, also called tartar, has formed under your gums. That is what’s causing the gums to bleed.
Plaque is an accumulation of food particles and microorganisms that create biofilms which are left on your teeth after eating. Sticky snacks are especially dangerous and adhere more readily to tooth surfaces. 
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