国外资料报道,按常规使用含氟化物(特别是氟化亚锡或氟磷酸钠)的牙膏刷牙,在青年人和老年人中均能减少龋齿的发病率,故这种牙膏又称为防龋牙膏。这是由于牙膏中的氟磷酸钠或氟化亚锡与牙齿的羟基磷灰石表面作用,形成了致密的氟化钙或磷酸锡薄层,能有效地防护牙釉质不受腐蚀。但为此目的而使用的氟化钠牙膏则收效较少,这是由于加入 Foreign materials, according to conventional use of fluoride (especially stannous fluoride or sodium fluoride) toothpaste brushing, in young people and the elderly can reduce the incidence of dental caries, so this toothpaste, also known as anti-caries toothpaste. This is due to the surface effect of sodium fluorophosphate or stannous fluoride in the toothpaste on the hydroxyapatite surface of the tooth, resulting in a dense layer of calcium fluoride or tin phosphate which effectively protects the enamel from corrosion. However, the sodium fluoride toothpaste used for this purpose is less effective because of the addition