Eat fruits and vegetables
Eating crunchy raw fruits may help scrub away the plaque when chewing. Especially, strawberries and pineapples have been said to bring a change.
To illustrate, malic acid in strawberries and baking soda removes discoloration and stains. Use the method by smashing the fruit and mixing with baking soda before brushing with the mixture.
Teeth brushing using powdered charcoal is claimed to remove stains and pull out tooth toxins.
Start by finely grinding charcoal and add a few water drops for wetting before brushing, then rinse your mouth.