EFFECT OF ACUTE FLUORIDE DOSES ON GROWTH OF ENAMEL

这一建议部分是基于一项临床调查的结果。 表明儿童中氟中毒的患病率很高 发生在有无氟饮用水的地区。消息来源 摄入的氟含量尚不清楚。这项建议是针对 氟化物可能是通过摄取离散的， 高剂量的氟化物，可能是从氟化片中获得的，或者 含氟牙膏。很有可能这样的影响 急性氟化物剂量与慢性影响明显不同。 在饮用水中氟含量较高的地区观察到 水。 我们观察到釉质沉积遵循昼夜节律。 导致形成两种不同密度的牙釉质。它是 很可能有两种分泌型成釉细胞，或者 两个分泌细胞周期。这是一个重要的发现，与 牙釉质形成的基本机制。有节奏的牙齿 在老鼠的门牙中观察到牙齿上的条纹形成 表面和在人牙釉质中作为增量线。在大鼠体内 给药后牙釉质沉积加重。 氟化物。 目的是详细研究超矿化和矿化。 分泌期、成熟期和成熟期的次矿化期 牙齿的萌出区域涉及：(A) 釉质和釉质基质的超微结构：(B)牙釉质和牙釉质基质的长度 各占主导地位的时间；和(C)细胞结构 成釉细胞分泌各时相。第二，审查 并测量几个参数，包括氟化物血清 摄取急性氟化物剂量所产生的浓度。这个 目的是研究引起氟中毒的机制，以便 更好地定义最佳氟化物治疗以实现最大保护 不会对牙釉质产生不良影响。第三，确定 急性氟化物剂量是否影响叠加在 环境氟是一种添加剂，或者，正如这里所建议的，它是关键的 环境中的氟化物浓度可以减少或预防氟中毒。

This proposal is based, in part, on results of a clinical survey indicating a significant prevalence of fluorosis among children occurs in areas having non-fluoridated drinking water. The source of ingested F is not known. This proposal is directed at the possibility that fluoride is derived from the ingestion of discrete, high doses of fluoride, possibly obtained from fluoride tablets, or fluoridated tooth paste. It is very likely that the effects of such acute fluoride doses differ markedly from the chronic effects observed in areas of high fluoride concentrations in drinking water. We observed that enamel deposition follows a circadian rhythm resulting in formation of enamel of two different densities. It is very likely that there are two kinds of secretory ameloblasts, or two secretory cell cycles. This is an important finding pertaining to the basic mechanism of enamel formation. Rhythmic tooth formation has been observed in rat incisors as stripes on the tooth surface and in human enamel as incremental lines. In rats the cyclinical enamel deposition is accentuated by administration of fluoride. The purposes are to examine in detail the hypermineralized and the hypomineralized phases of the secretory, maturation, and erupted regions of the tooth with respect to: (a) the ultrastructure of enamel and enamel matrix; (b) the length of time during which each is predominant; and (c) the cytostructure of the ameloblasts secreting each phase. Secondly, to examine and measure several parameters, including fluoride serum concentrations resulting from ingesting acute fluoride doses. The goal is to investigate the mechanism causing fluorosis in order to better define optimal fluoride treatment for maximal protection without adverse effects on enamel. Thirdly, to determine whether the effect of acute fluoride doses superimposed on ambient fluoride is additive, or, as proposed here, that critical concentrations of ambient fluoride reduce or prevent fluorosis.