Baking soda for yellow teeth

Baking soda can loosen some surface stains, but it cannot bleach the natural color inside enamel or dentine.

Sodium bicarbonate is a mild abrasive used in some toothpastes. Tooth color may also reflect dentine, enamel wear, calculus, decay, or intrinsic staining that brushing cannot remove.

A dentist distinguishes surface stain from internal discoloration and checks for decay, cracks, gum disease, fillings, crowns, and veneers before whitening.

Use fluoride toothpaste and gentle brushing rather than scrubbing loose powder onto teeth. Professional cleaning or peroxide whitening may be considered after the cause is identified.

Ask whether the discoloration is external or intrinsic and whether restorations will match after whitening.