De Moor R J, Verbeeck R M, De Maeyer E A
Department of Operative Dentistry, University Gent, Belgium.
Dent Mater. 1996 Mar;12(2):88-95. doi: 10.1016/S0109-5641(96)80074-1.
The amounts of fluoride released by different glass ionomer formulations were compared on the basis of individual fluoride release profiles in order to derive the effect of the physical and chemical formulation on the fluoride release process.
The fluoride release profiles of each of five specimens of ten glass ionomer cements setting by an acid-base reaction were investigated. The profiles were obtained by determining the amount of fluoride released [F] after equilibrating the samples at 37 degrees C in distilled water for 140 d. The [[F],t]-profiles were compared with a Multivariate Data Analysis on the basis of a Principal Component Analysis.
The Multivariate Data Analysis reveals that eight of the ten glass ionomers can be classified into four distinct groups. When the cumulative amount of fluoride released by each sample, [F]c, is calculated and fitted as a function of time, a regression analysis (r > 0.99) reveals that [F]c for all samples is most adequately represented by [F]c = ([F]l x t)/(t + t1/2) + beta x square root of t, indicating that two kinetic processes are responsible for the fluoride release profiles.
A comparison of the parameters of this equation shows that the physicochemical rationale for the classification of the glass ionomers conforms to differences in the kinetics of these processes which are determined by the qualitative and quantitative chemical composition as well as by the presentation (hand-mixed vs. capsules) of the glass ionomer. From the classification, it becomes apparent that different formulations can result in the same fluoride release profiles.
根据不同玻璃离子体配方的个体氟释放曲线，比较其氟释放量，以推导物理和化学配方对氟释放过程的影响。
研究了通过酸碱反应固化的十种玻璃离子水门汀的五个样本中每个样本的氟释放曲线。通过将样品在37℃的蒸馏水中平衡140天后测定释放的氟量[F]来获得曲线。基于主成分分析，将[[F],t]曲线与多变量数据分析进行比较。
多变量数据分析表明，十种玻璃离子体中的八种可分为四个不同的组。当计算每个样品释放的氟的累积量[F]c并将其拟合为时间的函数时，回归分析（r>0.99）表明，所有样品的[F]c最适合用[F]c = ([F]l×t)/(t + t1/2)+β×√t表示，这表明氟释放曲线由两个动力学过程决定。
该方程参数的比较表明，玻璃离子体分类的物理化学原理符合这些过程动力学的差异，这些差异由定性和定量化学组成以及玻璃离子体的呈现形式（手工混合与胶囊）决定。从分类中可以明显看出，不同的配方可能导致相同的氟释放曲线。
