Hellwig Elmar, Polydorou Olga, Lussi Adrian, Kielbassa Andrej M, Altenburger Markus J
Department of Operative Dentistry and Periodontology, University Clinic of Dentistry, Albert-Ludwigs-University Freiburg, Freiburg, Germany.
Quintessence Int. 2010 Oct;41(9):773-7.
To determine the formation and dissolution of calcium fluoride on the enamel surface after application of two fluoride gel-saliva mixtures.
From each of 80 bovine incisors, two enamel specimens were prepared and subjected to two different treatment procedures. In group 1, 80 specimens were treated with a mixture of an amine fluoride gel (1.25% F-; pH 5.2; 5 minutes) and human saliva. In group 2, 80 enamel blocks were subjected to a mixture of sodium fluoride gel (1.25% F; pH 5.5; 5 minutes) and human saliva. Subsequent to fluoride treatment, 40 specimens from each group were stored in human saliva and sterile water, respectively. Ten specimens were removed after each of 1 hour, 24 hours, 2 days, and 5 days and analyzed according to potassium hydroxide-soluble fluoride.
Application of amine fluoride gel resulted in a higher amount of potassium hydroxide-soluble fluoride than did sodium fluoride gel 1 hour after application. Saliva exerted an inhibitory effect according to the dissolution rate of calcium fluoride. However, after 5 days, more than 90% of the precipitated calcium fluoride was dissolved in the amine fluoride group, and almost all potassium hydroxide-soluble fluoride was lost in the sodium fluoride group. Calcium fluoride apparently dissolves rapidly, even at almost neutral pH.
Considering the limitations of an in vitro study, it is concluded that highly concentrated fluoride gels should be applied at an adequate frequency to reestablish a calcium fluoride-like layer.
确定两种氟凝胶 - 唾液混合物应用于牙釉质表面后氟化钙的形成与溶解情况。
从80颗牛切牙中各制备两个牙釉质标本，并进行两种不同的处理程序。在第1组中，80个标本用胺氟凝胶（1.25% F⁻；pH 5.2；5分钟）和人唾液的混合物处理。在第2组中，80个牙釉质块用氟化钠凝胶（1.25% F；pH 5.5；5分钟）和人唾液的混合物处理。氟处理后，每组40个标本分别储存在人唾液和无菌水中。在1小时、24小时、2天和5天后各取出10个标本，并根据氢氧化钾可溶性氟进行分析。
应用胺氟凝胶后1小时，产生的氢氧化钾可溶性氟量高于氟化钠凝胶。根据氟化钙的溶解速率，唾液发挥了抑制作用。然而，5天后，超过90%沉淀的氟化钙在胺氟组中溶解，而在氟化钠组中几乎所有的氢氧化钾可溶性氟都损失了。即使在几乎中性的pH值下，氟化钙显然也会迅速溶解。
考虑到体外研究的局限性，得出结论：应适当频率应用高浓度氟凝胶以重新建立类似氟化钙的层。
