Chemical and structural challenges in remineralization of dental enamel lesions.
Chemical and structural challenges in remineralization of dental enamel lesions.
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牙釉质病变再矿化的化学和结构挑战。
DOI：
10.1111/j.1600-0722.1989.tb01615.x
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Ole Fejerkov
中科院分区：
文献类型：
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作者：
Mogens Joost Larsen;Ole Fejerkov
本文的目的是确定一些化学和结构因素，可能会阻止龋齿病变的完全再矿化，并研究是否有可能克服这些障碍。粉末状釉质磷灰石样品用相对于釉质羟基磷灰石和氟磷灰石亚稳过饱和的溶液平衡。在20 ℃下平衡10分钟和60分钟后，将悬浮液离心，并测定上清液中的钙和磷酸盐浓度以及pH。在平行研究中，根据Thylstrup和Fejerskov的分类，严重程度为5-7的27颗氟斑牙的50个75微米厚的切片通过显微放射照相术和偏振光检查，使用蒸馏水和Replett介质或在空气中干燥。查明了阻碍非商业化的五个障碍：1）虽然矿化溶液或唾液相对于釉质磷灰石是过饱和的，但溶解在其中的钙和磷酸盐的总量很小，使得溶解的矿物质沉淀后仅为1/20，000 -1/30，矿化溶液的体积的0.000被矿物占据。2）从矿化溶液到釉质的浓度梯度小，这表明缓慢扩散进入和离开病变。3)釉质磷灰石晶体对钙和磷酸盐的吸收是如此迅速，以至于可以推测在病变的较深部分中孔内的水相仅略微过饱和。4)釉质病变的表层被发现是一个严重的矿化障碍，使一个亚表面区域保持低矿化后，暴露于唾液矿化，甚至终身。5)新磷灰石晶体的成核以替代失去的晶体是一个尚未解决的问题。
The aim of the present paper was to identify some chemical and structural factors which may prevent a full remineralization of caries lesions and to study whether it is possible to overcome such obstacles. Samples of powdered enamel apatite were equilibrated with solutions metastably supersaturated with respect to enamel hydroxyapatite and fluorapatite. After 10 min and 60 min of equilibration at 20 degrees C the suspensions were centrifuged and the calcium and phosphate concentrations and the pH were determined in the supernatant. In parallel studies, 50 75-microns-thick sections of 27 fluorotic teeth of a severity of 5-7 according to Thylstrup and Fejerskov's classification were examined by microradiography and in polarized light using distilled water, and Thoulett's media or seen dry in air. Five obstacles inhibiting remineralization were identified: 1) Although remineralizing solutions or saliva are supersaturated with respect to enamel apatite the total amount of calcium and phosphate dissolved in it is small, so that after precipitation of the dissolved mineral only 1/20,000-1/30,000 of the volume of the mineralizing solution is occupied by mineral. 2) The concentration gradients from the mineralizing solution into the enamel is small, which indicates a slow diffusion into and out of the lesion. 3) The uptake of calcium and phosphate by the enamel apatite crystals is so rapid that the aqueous phase within the pores can be presumed to be only marginally supersaturated in the deeper parts of the lesion. 4) The surface layer of the enamel lesions was found to be a serious obstacle to remineralization so that a subsurface area remains hypomineralized after exposure to salivary remineralization even for a lifetime. 5) Nucleation of new apatite crystals to substitute lost crystals is an unsolved problem.