Newbrun E.
Department of Stomatology, University of California, San Francisco, San Francisco, CA, USA.

Abstract: Early dentifrices contained natural ingredients, mostly in coarse particle form, and were quite abrasive. Salts, either sodium chloride, sodium bicarbonate, or a mixture of both, have also been used for tooth cleaning because of their ready availability and low cost. Because of both their relatively low intrinsic hardness and their high solubility, another advantage is low abrasivity. Their biggest disadvantage is a salty, unpalatable taste. Many modern dentifrices that contain sodium bicarbonate, either as the sole abrasive or one of several, disguise the saltiness with flavoring and sweetening agents. An almost inverse relationship exists between the percentage of baking soda in a dentifrice and its abrasivity. Sodium bicarbonate has no anticaries activity per se but is compatible with fluoride. In high concentrations, sodium bicarbonate is bactericidal against most periodontal pathogens. Most clinical studies have not found significant differences in periodontal response to baking soda as compared with other commercial dentifrices, probably because of its rapid clearance from the gingival sulcus. Sodium bicarbonate may not be the "magic bullet" for curing dental diseases, but its safety (if ingested), low abrasivity, low cost, and compatibility with fluoride make it a consummate dentifrice ingredient.