生物活性玻璃NovaMin诱导脱矿牙本质再矿化

目的：探讨生物活性玻璃NovaMin诱导脱矿牙本质再矿化效果，并定性研究再矿化层的理化性质。方法：制备厚度为1 mm冠部牙本质片，用乙二胺四乙酸(ethylenediaminetetraacetic acid，EDTA)浸泡48 h，制备完全脱矿牙本质样本，并平均分为人工唾液组和NovaMin组。每天用人工唾液和生物活性玻璃NovaMin分别处理牙本质片表面2 min，每天2次，间隔8 h，然后将样本浸泡在37 ℃人工唾液中恒温保存。7 d后用扫描电子显微镜(scanningelectron microscope，SEM)、能谱分析仪(energy dispersive X-ray，EDX)、傅里叶变换衰减全反射红外光谱(att enuated totalrefl ectance Fourier transform infrared spectroscopy，ATR-FTIR)和X射线衍射仪(X-ray diff raction，XRD)观察和检测牙本质表面矿化物的形成及其理化性质。结果：SEM结果显示：NovaMin组的完全脱矿牙本质表面形成了矿化晶体层，完全封闭了暴露的牙本质小管，经EDX，ATR-FTIR和XRD分析发现这一矿化层主要组分为钙和磷，且结构类似于牙本质磷灰石。而人工唾液组牙本质表面并没有再矿化层的形成，牙本质小管仍然开放。结论：NovaMin能促进完全脱矿的牙本质表面再矿化，形成类似牙本质羟基磷灰石的晶体结构。

Remineralization of demineralized dentin induced by bioactive glass NovaMin

Objective: To explore the remineralization effect of bioactive glass NovaMin on demineralizeddentin specimens, and to study the physical and chemical properties of formed structure at dentinsurface.Methods: One mm-thickness coronal dentin slices were soaked in ethylene diamine tetraaceticacid (EDTA) for 48 h to prepare the completely demineralized dentin specimens and they weredivided into 2 groups: an artificial saliva group (control group) and a NovaMin powder group. Thespecimens were treated with artificial saliva or NovaMin powder for 2 min (2 times every day), andthe interval was 8 hours. Then, the specimens were soaked in the remineralization solution. After7 days, the scanning electron microscope (SEM), energy dispersive X-ray (EDX), attenuated totalreflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD) wereused to detect dentin morphology, the physical and chemical properties of the formed structure atdentin surface.Results: The results of SEM showed that a defined surface layer in the NovaMin powder groupcould be observed in the SEM imaging at the 7th day, which completely occluded dentinal tubules;the EDX, ATR-FTIR and XRD analysis found that the mineralized layer formed at dentin surfacewas mainly composed of calcium and phosphate elements, which was similar to the hydroxyapatitelikecrystal. However, there were no materials formed at the dentin surface in the control group, andthe dentinal tubules were still open.Conclusion: NovaMin can remineralize the demineralized dentin specimens and occlude thedentinal tubules in hydroxyapatite-like crystal structure.