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Baking soda is a mild abrasive that can scrub plaque and surface stains off of your teeth. You can apply it to your teeth as a whitener in a number of ways: Dip a dampened toothbrush directly into powdered baking soda. Brush your teeth as you normally would, spit out the baking soda, and rinse your mouth with water. Make a paste of baking soda and water. Put some baking soda in a small container that you can close (to store the paste). Slowly stir water a few drops at a time into the baking soda until a smooth paste forms. Apply to your toothbrush, then brush and rinse your teeth as normal. Baking soda might irritate the tissues of your mouth. If you notice any inflammation or soreness, use this treatment less frequently. Baking soda combined with hydrogen peroxide makes a very effective teeth whitener. This treatment, however, should not be used frequently. Hydrogen peroxide can irritate the tissues of your mouth, and prolonged use may cause serious problems. To make this whitener: Pour a teaspoon of baking soda into a bowl or small dish. Stir five to seven drops of hydrogen peroxide into the baking soda until a smooth paste forms. You can also add a drop of peppermint extract to improve the flavor of the mixture. Apply to your toothbrush, then brush and rinse your teeth as normal. Be sure to spit out all of the peroxidedo not swallow it. Rinse your mouth well afterwards. Since the citric acid found in lemon juice is a natural bleaching agent, it can make a great whitening agent. You can make a paste by combining the two ingredients, and use it infrequently as a whitener. Pour a teaspoon of baking soda into a bowl or small dish. Stir lemon juice a few drops at a time into the baking soda until a smooth paste is formed. Apply the paste to your teeth (using a finger is fine) and let it sit for two to three minutes. Rinse your teeth with water afterwards. Use this treatment no more than once a week, as citric acid can also damage the enamel of your teeth, and irritate the tissues of your mouth. Vinegar is acidic, like lemon, and so it can help to whiten your teeth, especially when combined with baking soda. A mixture of the two can be used as a paste to brush your teeth clean. Pour a teaspoon of baking soda into a bowl or small dish. Stir vinegar a few drops at a time into the baking soda until a smooth paste is formed. Dip a dampened toothbrush in the paste and brush as normal. Rinse your mouth with water afterwards.
Use baking soda directly on your teeth. Make a paste of baking soda and hydrogen peroxide. Mix baking soda and lemon juice. Make a paste of baking soda and vinegar.