THE MINERAL DISTRIBUTIONS AND THEIR PROMOTION OF FLUORIDE RETENTION IN TH EPLAQUE in vivo EXPOSED TO A MINERAL ENRICHING MOUTHRINSE

本研究的目的是阐明矿物质(Ca和P)在牙菌斑中的分布及其对氟离子滞留的促进作用，并对影响氟离子滞留的因素进行评估。11名年龄在20~31岁之间的受试者，在上颌磨牙颊面安装有牙菌斑容器(直径2 mm)的取样装置。在菌斑形成超过3天后，受试者被指示用5种洗涤液中的一种进行冲洗，每天3次，连续4天。每种溶液都是从矿物质浓缩剂(尿素500 mM，CaCl220 mM，Na_2HPO_4 12 mM，Na_2PO_3F(MFP)5 mM，pH_5)中去掉一些成分制成的。使用不同的溶液每隔一段时间重复斑块收集。暴露在不含任何成分的安慰剂溶液中的斑块样本作为对照。最后一次漂洗24小时后，将样品冷冻干燥，然后将其嵌入甲基丙烯酸酯混合物中。用超微切割机从牙菌斑外表面向釉质方向重复切割一系列平行于牙面的菌斑切片(6微米时4个，3微米时2个)。用较薄的切片进行面积测量以评估样本量。较厚的切片被收集成几个一致的标本。用Kato等人报道的方法分析了斑块中的氟化物和矿物分布。阿奇口述传记。42：521-525,1997。除较深的斑块层外，氟化物滞留量增加。在同时含有MEP和矿物质的溶液中，氟浓度(0.5-3.6nmol/mm^3)显著升高，这种趋势在满口含氟时更明显。只有在接触矿物质富集剂的斑块中，钙和磷的水平都显着增加。然而，方差分析表明，不同受试者之间的差异将是一个比口红类型更强的影响氟在斑块中滞留的因素。

The aim of this study was to clarify the mineral (Ca and P) distributions and their promotion of fluoride retention in the plaque in vivo exposed to a mineral enriching mouthrinse and then to estimate factors, which have an influence on the promotion of fluoride retention in the plaque. 11 subjects consenting (20-31 years), had sampling devices containing plaque receptacles (2mm in diameter) to buccal surfaces of upper molars. After plaque had formed over 3 days, subjects were instructed to rinse with one of five rinsing solutions three times a day on 4 consecutive days. Each solution was made by excluding some ingredients out of a mineral enriching mouthrinse (urea 500mM, CaCl_2 20mM, Na_2HPO_4 12mM, Na_2PO_3F(MFP) 5mM, pH_5). Plaque collections were repeated at intervals using different solutions. Plaque samples exposed to a placebo solution with no ingredients served as control. 24 hours after the last rinsing, the sample was freeze-dried and then embedded in a methacrylate mixture. A series of plaque sections parallel with the tooth surface (4 at 6mum then 2 at 3mum) were repeatedly cut from the outer plaque surface towards the enamel, using an ultramicrotome. The thinner sections were used for area measurement to evaluate sample volume. The thicker sections were collected into several congruous specimens. Fluorides and mineral distributions in plaque were analyzed by a method reported by Kato et al. Archs oral Biol. 42 : 521-525, 1997. Fluoride retention increased except in the deeper plaque layers. Fluoride concentrations (0.5-3.6nmol/mm^3) significantly rose in the samples exposed to solutions containing both MEP and minerals, this tendency being greater in the full mouthrinse. Both calcium and phosphorus levels significantly increased only in the plaque exposed to the mineral enriching mouthrinse. However, ANOVA indicated a difference between subjects would be a stronger factor than the type of mouthrinse for fluoride retention in plaque.