微量元素矿化液促进釉质龋再矿化层形成机理的研究

A Study of the Mechanism of Effects of Solution Containing Trace Elements on Remineralization Layer Formation of Enamel Carious Lesions

目的 :观察不同成份的再矿化液对人工釉质龋表层下脱矿的再矿化作用及再矿化层的形成机理。方法 :选择牛牙 36颗于乳酸凝胶中形成人工釉质龋 ,两周后将以上脱矿釉质块随机分成 4组样本 ,其中 3组为实验组 ,1组为对照组。实验组釉质块分别置无氟、含氟及含有氟、钙、磷、锡等微量元素的再矿化液中 ;对照组用去离子水代替再矿化液。借助X光电子能谱、扫描电镜、偏光显微镜等 ,观察不同的矿化液处理人工釉质龋后脱矿釉质表面沉积物的组份结构及再矿化效果。结果 :与对照组相比 ,所有矿化液均有促进再矿化的作用 ,尤以氟微量元素矿化液组明显 ,X光电子能谱显示再矿化釉质表面的沉积物是以CaF2 、羟基磷灰石、非特异性氟吸附物等共同形成沉积物的形式存在 ,扫描电镜观察釉质表面有不规则的矿物沉积并结晶化 ;偏光镜下以脱矿为主的正性双折射区明显减少 ,主要表现为以再矿化为主的负性双折射区。结论 :含氟及微量元素的矿化液具有促进再矿化的作用 ,其机理可能是在脱矿的釉质表面通过氟化钙或非特异性氟吸附物等矿物质 ,不是传统认为形成氟磷灰石而实现的。在相同氟离子浓度下含氟及微量元素的矿化液具有比单纯含氟矿化液的再矿化能力强 ,其机理可能是氟与微量元素的协同作用。

Objective: To study the effects of several remineralization solutions with different composition on the artificial demineralization lesions of bovine enamel and the mechanism of remineralization layer formation. Methods: 36 bovine teeth were selected and artificial carious lesions were formed with lactic acid gel. Then all specimens were divided into 4 groups which contained no fluoride, fluoride, fluoride calciulm phospate tin, and de ionic water separately, and the de ionic group was taken as control. The structure and composition of the sediments on the enamel surface were evaluated and detected by X ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Histological change of enamel section was examined by polarized microscopy. Results: Compared with the control group, all the solutions had remineralization effects, especially the solutions containing trace elements. XPS showed that there were sediments formed on the surface of carious lesion, the compositions of the sediments were CaF\-2, HAP and non specifically absorbed fluoride (NSAF). Irregular, crystal deposits were also found under SEM on the enamel surface. The polarized microscopy results showed that the observed demineralization areas decreased after exposure to the solu tions. Conclusion: Solutions containing fluoride and trace elements were effective on remineralization. The possible mechanism is that CaF\-2 and NSAF, instead of FA formed in the remineralization layer. Moreover, the remineralization effects of the fluoride solutions containing trace elements are more outstanding than that without trace elements. The potential mechanism is the synergistic action of fluoride and trace elements.\;