3 Apple Vinegar
This is a very simple procedure to help with your teeth. All you do is let your toothbrush soak in a glass of apple vinegar for about 3 minutes. Then you just use the toothbrush to brush the tartar build up, but brush properly to get rid of as much as possible.
After that, rinse your mouth and your toothbrush and then proceed to brush with toothbrush like normal, but making sure to clean the cavity as much as possible.