When you brush your teeth, even very gently, if you notice that there are traces of blood on your toothbrush it may mean you are suffering from gingivitis. The cause of this is a type of bacteria which grows in your mouth, on the teeth and under the gums, causing plaque and tartar to form. Symptoms of this condition include bad breath, mouth sores or ulcers, swollen gums, bleeding and an inflamed or the bright red appearance of the gums.

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