中药五倍子多酚性化合物促脱矿牙釉质和人工羟磷灰石再矿化作用的观察

Role of Enamel Organic Matrix in the Remineralization of Initial Demineralized Enamel and Artificial Hydroxylapatite Treated with Galla chinensis

目的观察中药五倍子多酚性化合物(GCE)促脱矿釉质和人工羟磷灰石再矿化的作用,分析釉质有机质对GCE促釉质龋再矿化作用的影响,研究GCE促进早期釉质再矿化的作用机制。方法制备人工常规牛牙釉质龋、去有机质牛牙釉质龋标本及脱矿人工羟磷灰石标本。体外pH循环条件下用GCE处理不同脱矿标本。采用显微硬度计测定标本pH循环前后的硬度值,比较各标本表面显微硬度变化。扫描电镜观察pH循环前后各组标本再矿化层的形貌特点。结果 pH循环后,GCE处理的常规釉质龋组的显微硬度较PH循环前增加,扫描电镜下有大量分布不均匀、形状不规则的颗粒聚集成簇。GCE处理的去有机质牙釉质龋组及人工羟磷灰石脱矿组显微硬度较pH循环前差异无统计学意义(P>0.05),且与阴性对照组的差异也无统计学意义(P>0.05)。扫描电镜下标本表面仍呈现凹坑状的不规则外观,较之pH循环前无明显改变。结论 GCE具有促进早期釉质龋再矿化的作用,釉质有机质在该作用中扮演了重要角色,当牙釉质有机质去除或缺失时,GCE促进早期釉质龋再矿化的作用尚不显著。

Objective To observe the remineralization of initial demineralized enamel and artificial hydroxylapatite treated with Galla chinensis in vitro,and to assess the effect of enamel organic matrix on the potential of Galla chinensis to promote the remineralization of initial enamel carious lesions,further to elucidate the mechanism of Galla chinensis in promoting the remineralization of initial enamel carious lesion.Methods Bovine sound enamel blocks,non-organic enamel blocks and artificial hydroxylapatite blocks were demineralized and exposed to a pH-cycling.During the pH-cycling,the specimens were randomly treated with 1 g/L NaF,4 g/L Galla chinensis extract(GCE) or double deionized water(DDW).Surface microhardness of all the samples was measured before and after the pH-cycling,and percentage surface microhardness recovery(%SMHR) was calculated.The surface morphology was observed by scanning electron microscopy.Results A significant increase in microhardness(P0.05).No obvious changes in the SEM images of regular enamel treated with DDW,enamel disposed of its organic matrix or artificial hydroxylapatite treated with GCE compared to those of them before pH-cycling.Conclusion Galla chinensis enhances the remineralization of initial enamel carious lesions in vitro.The organic matrix of enamel was shown to play a substantial role in the observed mechanism.