Oral Health Research Institute, Department of Preventive and Community Dentistry, Indiana University School of Dentistry, Indianapolis, IN 46202-2678, USA. dzero @ iupui.edu
Caries Res. 2010;44(2):90-100. doi: 10.1159/000284399. Epub 2010 Feb 16.
While the clinical anticaries efficacy of fluoride toothpaste is now without question, our understanding of the relation of fluoride efficacy to brushing time and dentifrice quantity is limited. The aim of this in situ study was to determine how differences in brushing time and dentifrice quantity influence (i) fluoride distribution immediately after brushing, (ii) clearance of fluoride in saliva, (iii) enamel fluoride uptake (EFU) and (iv) enamel strengthening, via the increase in surface microhardness. The study compared brushing times of 30, 45, 60, 120 and 180 s with 1.5 g of dentifrice containing 1,100 microg/g fluoride as sodium fluoride. In addition, 60 s of brushing with 0.5 g dentifrice was evaluated. A longer brushing time progressively reduced retention of dentifrice in the brush, thereby increasing the amount delivered into the mouth. A longer brushing time also increased fluoride concentrations in saliva for at least 2 h after the conclusion of brushing, showing that increased contact time promoted fluoride retention in the oral cavity. There was a statistically significant positive linear relationship between brushing time and both enamel strengthening and EFU. Compared to 0.5 g dentifrice, brushing with 1.5 g dentifrice more than doubled the fluoride recovered in saliva after brushing and increased EFU. In conclusion, the results of this preliminary, short-term usage study suggest for the first time that both brushing time and dentifrice quantity may be important determinants both of fluoride retention in the oral cavity and consequent enamel remineralization.
虽然氟化物牙膏的临床抗龋效果现在已毋庸置疑，但我们对氟化物功效与刷牙时间和牙膏用量之间的关系的了解还很有限。本原位研究的目的是确定刷牙时间和牙膏用量的差异如何影响（i）刷牙后立即的氟化物分布，（ii）唾液中氟化物的清除，（iii）牙釉质氟摄取（EFU）和（iv）通过表面显微硬度增加来增强牙釉质。该研究比较了使用含 1100μg/g 氟化物（以氟化钠计）的 1.5g 牙膏刷牙 30、45、60、120 和 180s 的时间，此外还评估了使用 0.5g 牙膏刷牙 60s 的情况。刷牙时间越长，牙膏在牙刷上的保留量就越低，从而增加了进入口腔的牙膏量。刷牙时间的延长也至少在刷牙结束后 2 小时内增加了唾液中的氟化物浓度，表明增加接触时间促进了口腔内氟化物的保留。刷牙时间与牙釉质强化和 EFU 之间呈显著正线性关系。与 0.5g 牙膏相比，使用 1.5g 牙膏刷牙后唾液中回收的氟化物增加了一倍以上，EFU 也增加了。总之，这项初步的短期使用研究的结果首次表明，刷牙时间和牙膏用量可能都是口腔内氟化物保留和随后牙釉质再矿化的重要决定因素。
