不同氟浓度涂膜对牙釉质表面显微硬度的影响

Influence or fluoride varnish of different concentration on microhardness of enamel surface

作者观察应用含不同浓度氟化钠涂膜后牙釉质表面显彼硬度值的改变情况。实验将釉质随机分为Ａ、Ｂ、Ｃ三组，先测出实验之前的显微硬度值。然后在这三组釉质表面分别涂上０．５％、１．５％、２．７％的氟化钠涂膜２４小时，再测显微硬度。结果：三组不同浓度氟化钠涂膜均使牙釉质显微硬度值有显著提高，与处理前比较，具高度显著性差异。Ａ组含０．５％氟化钠涂膜其显微硬度值的增加串仅是其它两组的一半，而Ｂ、Ｃ两组高浓度氟化钠涂膜之间其硬度值的增加率又几乎相同，这表明，在达到一定的氟浓度后，其硬度值不再增加。作者认为，使用含１．５％氟化钠涂膜对预防龋齿较为理想。

Varnish is a neotype oral material which develops rapidly in recently years,It have had extensive study abroad. It is one of the topical application of fluoride,among them, fluoride-sodium varnish have more significant effect on prevention of dental caries. This study observed the changes of microhardncss of cramels after applying fiuorid-sodium varnish of different concentration to emamel surfaces. Enamels were randomly parted into three groups,A. B and C. Before fluoride application, the microhardness of enamels were detected, and no significant difference were found among three groups, After that, 0.5%, 1. 5%, 2. 7% fluoride-sodium varnish were daubed respectively on the three groups enamel surfaces for 24h. The microhardness of enamels were detected again. The results showed all the microhardness of enamels have significant increase statistically after applying fluoride-sodium varnish of different concentration. But, for 0. 5% fluorid-Sodium varnish, the increase of microhardness of enamels was only one half of the other two groups, which suggested in some concentration range, the fluoride concentration increased one time,the microhardncss of enamels inereased about one time,But the increase of microhardness of enamels was not synchronized with the increase of fluoride concentration. The increase of microhardness of enamels is almost the same between the two high concentration fluoride-sodium varnish groups,and there in no significant difference statistically. That is when some fluoride concentration were reached, the microhardness of enamels won't increase any more. By the experiment, the writer suggests 1.5% fluorid-sodium varnish is the best on prevention of dental caries.