Faculty of Dentistry, The University of Hong Kong, Hong Kong.
Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
J Dent. 2021 May;108:103633. doi: 10.1016/j.jdent.2021.103633. Epub 2021 Mar 11.
To investigate the remineralizing effect of a strontium-doped bioactive glass (HX-BGC) and fluoride on demineralized enamel and dentine.
Sixty demineralized human tooth specimens were allocated to four groups. Group 1 received 5% HX-BGC, Group 2 received 5% HX-BGC and 1450 ppm fluoride, Group 3 received 1450 ppm fluoride, and Group 4 received deionized water as negative control. The specimens were subjected to pH cycling for 14 days. The surface morphology, lesion depths, crystal characteristics and collagen matrix degradation of the specimens were assessed by scanning electron microscopy (SEM), micro-computed tomography (mico-CT), X-ray diffraction (XRD), and spectrophotometry with a hydroxyproline (HYP) assay, respectively.
SEM images showed the enamel surface was smooth with regularly arranged enamel rods in Groups 1-3. Granular grains were observed in both inter-tubular and intra-tubular dentine in Groups 1-3. The mean lesion depths in enamel were 80.8 μm, 50.6 μm, 72.7 μm and 130.7 μm in Groups 1-4, respectively (p < 0.001), and those in dentine were 152.6 μm, 140.9 μm, 165.4 μm and 214.1 μm, respectively (p < 0.001). The differences in mean mineral loss in enamel and in dentine between the four study groups follow the same pattern as that of the differences in lesion depth. XRD illustrated apatite formation in each group. There were no significant differences in the HYP concentrations among the four groups (p = 0.261).
Combined use of HX-BGC and fluoride can reduce mineral loss and promote remineralization of demineralized enamel and dentine through the precipitation of newly formed apatite.
Adjunctive use of HX-BGC may enhance the remineralization effect of fluoride in the management of early dental caries lesions.
研究锶掺杂生物活性玻璃（HX-BGC）和氟化物对脱矿牙釉质和牙本质的再矿化作用。
将 60 个脱矿人牙标本分为 4 组。第 1 组接受 5% HX-BGC，第 2 组接受 5% HX-BGC 和 1450ppm 氟化物，第 3 组接受 1450ppm 氟化物，第 4 组接受去离子水作为阴性对照。标本经 pH 循环 14 天。采用扫描电子显微镜（SEM）、微计算机断层扫描（micro-CT）、X 射线衍射（XRD）和分光光度法（羟脯氨酸（HYP）测定）分别评估标本的表面形态、病变深度、晶体特征和胶原基质降解。
SEM 图像显示，第 1-3 组牙釉质表面光滑，牙釉柱排列规则。第 1-3 组牙本质管间和管内均可见颗粒状颗粒。牙釉质平均病变深度分别为 80.8μm、50.6μm、72.7μm 和 130.7μm（p<0.001），牙本质分别为 152.6μm、140.9μm、165.4μm 和 214.1μm（p<0.001）。4 组研究组的牙釉质和牙本质平均矿物质损失差异与病变深度差异相同。XRD 表明每组均有磷灰石形成。4 组间 HYP 浓度无显著性差异（p=0.261）。
HX-BGC 联合氟化物可减少矿物质损失，并通过新形成的磷灰石沉淀促进脱矿牙釉质和牙本质的再矿化。
辅助使用 HX-BGC 可能会增强氟化物在早期牙釉质龋管理中的再矿化作用。
