How many times a week is it safe to use baking soda to whiten your teeth?

Im using it in a tray probaby around a half and half mixture with toothpaste.
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You should do this once a week 1 brush your teeth with your regular toothpaste 2 then fill a cup with clean water 3 then get another cup and fill it with about 2 tbs of baking soda 4 Add one or two drops of your toothpaste with the baking soda then mix together 5 After that get your toothbrush wet and dip it into the paste and brush your teeth 6 Last you will want to rinse your mouth with the water you got before Hope this helps
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