摘要
用氟离子选择性电极测定了含氟牙膏中游离氟浓度,探讨了牙膏中总氟量的测定方法,研究了游离氟(F^-)与总氟(F)量的关系。结果表明,含氟牙膏中总氟量包括结合氟和游离氟两部分,其中只有F^-有防龋作用。当测得膏体中F^-与F的量相等或相近时,该牙膏才能提供足够浓度和稳定的F^-以保证牙膏的防龋性能。实验表明,对正常釉质而言F^-的存在可增强其抗酸脱矿能力,当F^-的质量分数w_(F^-)在4×10^(-4)～1×10^(-3)之间时有较好的防龋效果,当w_(F^-)降至2×10^(-4)以下则含氟牙膏已无防龋作用,因此磨擦剂为钙盐的含氟牙膏有效期至多为3个月,故生产厂家必须注明出厂期及有效期。同时,实验还表明若除F^-外还同时存在Ca^(2+),PO_4^(3-)等矿物盐离子可以使早期龋再矿化达最佳效果。
The concentration of free F ions in fluoride toothpastes is determined by means of fluoride selective-electrode. The determination method of total F contents and relationship between free F and total F in fluoride toothpaste are studied. The results indicate that total F consists of free F and combined F, but only free F has anti-caries effect. While free F equals or approches total F, the toothpaste just supply enough free F, which concentration is in the range 400×10^(-6) and 1000×10^(-6) for ensuring the best anti-caries effect. While free F go down to 200×10^(-6), the anti-caries effect disappears. The period of validity of the toothpaste, taking CaCO_3 as abra- sive, is three months at the most. So, production factories of the toothpaste must give clear indication of production date and period of validity. Experi- ments show that free F can enhance ability of anti-caries effect. Meanwhile, if Ca^(2+), PO_4^(3+) and other mineral salts ions exist also, it must have the best remineralized effect for early caries.
出处
《北京师范大学学报（自然科学版）》
CAS
CSCD
1993年第1期113-116,共4页
Journal of Beijing Normal University(Natural Science)
基金
国家自然科学基金
关键词
牙膏
游离氟
氟
抗龋
toothpaste, free F, total F, anti-caries
