Baking soda or sodium bicarbonate is being utilized more and more in toothpaste as an abrasive and chemical remover of stain. The chemical action of sodium bicarbonate is a superior cleaning power. It is a much milder abrasive than other types of fine particles found in many of the whitening toothpastes.
That means that it does not remove surface enamel as quickly as other types of dental cleaners. How slowly does it abrade? Well, studies measuring radioactive dentin show half to one third as much enamel. That means that people who have sensitive teeth should stay away from the more abrasive types of toothpaste and stick with the ones that have baking soda.