Hashizume Lina Naomi, Lima Ynara Bosco de Oliveira, Kawaguchi Yoko, Cury Jaime Aparecido
Department of Preventive and Social Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
J Oral Sci. 2003 Dec;45(4):193-9. doi: 10.2334/josnusd.45.193.
The decline of dental caries in the industrialized countries can be attributed to widespread use of fluorides. The Japanese market share of dentifrices containing fluorides has increased from 12% in 1985 to 77% in 2000. For a fluoride dentifrice to be effective in the control of dental caries, an adequate concentration of the fluoride must be soluble. Several Japanese fluoride dentifrices have in their formulations calcium phosphate as an abrasive, which may react with fluoride. This study was designed to evaluate the availability and stability of fluoride in the most consumed dentifrices in Japan. The analyses were made when the dentifrices were purchased (fresh samples) and after one year of storage (aged samples) at room temperature (21.8 +/- 3.6 degrees C). Total fluoride and soluble fluoride was determined using an ion specific electrode. All dentifrices showed similar concentrations of total fluoride in fresh and aged samples in accordance with the Japanese Legislation (content of less than 1,000 ppm F). Some dentifrices, with dicalcium phosphate as abrasive, showed decreasing concentrations of total soluble fluoride and increasing amounts of insoluble fluoride over time. Although most of the Japanese fluoridated dentifrices evaluated in this study contain unstable fluoride, they were found to have sufficient concentrations of soluble fluoride to be effective in preventing dental caries.
工业化国家龋齿发病率的下降可归因于氟化物的广泛使用。含氟牙膏在日本的市场份额已从1985年的12%增至2000年的77%。要使含氟牙膏有效控制龋齿，必须有足够浓度的可溶氟化物。一些日本含氟牙膏在配方中使用磷酸钙作为研磨剂，这可能会与氟化物发生反应。本研究旨在评估日本最常用牙膏中氟化物的有效性和稳定性。分析在购买牙膏时（新鲜样品）以及在室温（21.8±3.6摄氏度）下储存一年后（老化样品）进行。使用离子选择性电极测定总氟化物和可溶氟化物。根据日本法规（氟含量低于1000 ppm），所有牙膏的新鲜样品和老化样品中的总氟化物浓度相似。一些以磷酸二钙作为研磨剂的牙膏，随着时间推移，总可溶氟化物浓度降低，不溶氟化物含量增加。尽管本研究中评估的大多数日本含氟牙膏含有不稳定的氟化物，但发现它们具有足够浓度的可溶氟化物来有效预防龋齿。
