Newbrun E
Department of Stomatology, University of California, San Francisco, San Francisco, California, USA.
Compend Contin Educ Dent Suppl. 1997;18(21):S2-7; quiz S45.
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.
早期的牙膏含有天然成分，大多呈粗颗粒状，且研磨性很强。盐，无论是氯化钠、碳酸氢钠，还是两者的混合物，也因其易于获取和成本低廉而被用于清洁牙齿。由于它们相对较低的固有硬度和高溶解性，另一个优点是研磨性低。它们最大的缺点是有咸味，味道不佳。许多含有碳酸氢钠的现代牙膏，无论是作为唯一的研磨剂还是几种研磨剂之一，都用调味剂和甜味剂来掩盖咸味。牙膏中小苏打所占的百分比与其研磨性之间几乎呈反比关系。碳酸氢钠本身没有防龋活性，但与氟化物相容。在高浓度下，碳酸氢钠对大多数牙周病原体具有杀菌作用。大多数临床研究发现，与其他商业牙膏相比，使用小苏打对牙周的反应没有显著差异，这可能是因为它能迅速从龈沟清除。碳酸氢钠可能不是治疗牙齿疾病的“神奇子弹”，但其安全性（如果摄入）、低研磨性、低成本以及与氟化物的相容性使其成为一种完美的牙膏成分。
