早期釉质龋病变体部的透射电镜观察

[目的]探讨早期釉质龋中釉质微晶的溶解方式及病变体部的形成机制。[方法]应用透射电子显微镜(TEM)结合氩离子减薄制样技术对早期釉质龋病变体部的超微结构进行观察。[结果]在早期釉质龋病变体部,釉柱间区增宽,釉柱中心区徽晶的破坏程度较周边严重,釉柱中心区多数微晶出现中心穿孔,釉柱周边两侧微晶边缘圆钝、增大,并可见大量形态不一、大小不等的晶粒散布其间。[结论]早期釉质龋中单个晶粒的溶解方式主要表现为中心部优先溶解;早期釉质龋病变体部的形成,是以微晶脱矿为主,脱矿和再矿化过程同时存在的结果。

Transmission Electron Microscopic Study on the Body of the Lesion in Incipient Enamel Caries

[Objective ] To investigate the carious dissolution mechanism of individual enamel crystals and formation mechanism of the body of the lesion in incipient enamel caries. [Methods]The body of the lesion in incipient enamel caries was observed by transmission electron microscopy (TEM, 200 kV), combined with selected-area argon-ion-beam thinning technique. [Results]In the body of the lesion, sheath region was enlarged. The crystals located in the prism cores were destroyed in the more serious degree than at the prism periphery. In the center of the enamel rod, the preferential core perforation was found in most enamel crystals. At the prism periphery, the presence of larger acid-resistant apatite crystals with rounded edge could be observed. In addition, a number of crystals with different size and shape were observed in the enlarged sheath region. [Conclusion]The individual crystal dissolution mainly occurs as the preferential crystal core dissolution. The body of the lesion in incipient enamel caries may be a result of a shift in the equilibrium between demineralization and reminderalization processes, with the demineralization process predominant.