氟以及表面活性剂对牛牙釉质脱矿的影响

本研究旨在进一步了解氟化物以及表面活性剂（ＳＡＡ）对牛牙釉质脱矿的影响。在体外模拟酸蚀模型，采用自制的钙离子选择性微电极测试不同处理组的钙离子浓度，并进行分析评价。结果显示：①牙釉质经氟化钠处理后其脱矿率明显低于单酸蚀液组（Ｐ〈０．０１）；②ＳＡＡ和氟化钠全用与单用氟化钠组之间无显著差异（Ｐ〉０．０５）。提示氟可通过增强牙齿组织的抗酸性，降低釉质表面的溶解度而抗龋；ＳＡＡ的抗龋作用有待进一步研究。     

柠檬酸致牙釉质脱矿的研究

目的 观察10%柠檬酸酸蚀牙釉质不同时间的效果,以获得研究早期釉质龋的可靠体外实验模型,探索更高效的牙釉质脱矿实验方法.方法 选取离体人恒前磨牙切割制成牙釉质块,经10%柠檬酸及部分饱和酸缓冲脱矿系统脱矿,扫描电镜观察牙釉质表面经柠檬酸酸蚀不同时间(90 s、120 s、150 s)及部分饱和酸缓冲脱矿系统脱矿1周后的形态学特征,并用显微硬度计检测标本脱矿前后表面显微硬度.结果 牙釉质进行脱矿处理后,釉质表面呈现酸蚀状外观.酸蚀90 s时,仅见小部分釉柱晶格脱矿溶解,脱矿牙釉质的能力有限;酸蚀120 s时,与早期自然龋损近似,呈蜂窝状;酸蚀150 s时,牙釉质表面呈酸蚀样破坏形貌,属于过度酸蚀;而部分饱和酸缓冲脱矿系统脱矿效果相对较差.结论 柠檬酸具有较强的酸蚀作用,其脱矿牙釉质的能力随着时间的延长而增强,10%的柠檬酸酸蚀120 s可获得早期釉质龋模型.     

氟化钠抗碳酸饮料酸蚀乳牙釉质作用的研究

目的：探讨氟化钠抗碳酸饮料对乳牙釉质酸蚀的效果。方法：用人下颌乳切牙制备72个釉质块,将其随机平均分为3组：对照组釉质块不作涂氟处理,实验组两组釉质块分别涂0.6%和1.23%浓度氟化钠;各组再按浸泡在碳酸饮料中的时间不同分成30 min和50 min两个亚组。将各组釉质块分别浸泡于碳酸饮料中30 min或50 min,取出后用去离子水冲洗,将实验组重新涂氟,然后再将釉质块浸泡在碳酸饮料中,如此循环直至12 h。用扫描电镜观察乳牙釉质表面形态改变,显微硬度计测定釉质表面硬度值（surface micro-hardness,SMH）变化,评估氟化钠保护乳牙釉质抗碳酸饮料酸蚀的效果。结果：与对照组比较,经两种浓度氟化钠处理过的乳牙釉质能不同程度地抵抗碳酸饮料的酸蚀作用,SMH值较高（P〈0.05）;随着碳酸饮料浸泡时间的延长,氟化钠保护乳牙釉质抗酸蚀的能力下降;较高浓度的氟化钠的保护效果更好,差异有统计学意义（P〈0.05）。结论：氟化钠能够增强乳牙釉质抗碳酸饮料酸蚀能力。     

两种局部用氟对预防正畸牙脱矿的临床研究

目的了解固定矫治器治疗后牙齿牙釉质脱矿的发生率及严重程度，评价用75％氟化钠处理牙面和使用含氟牙膏对减轻牙釉质脱矿的作用。方法选择固定矫治器治疗的患者93例随机分为3组，氟化钠糊剂组34例，含氟牙膏组28例，对照组31例，治疗前后对牙面脱矿情况进行临床观察。结果矫治前3组患者牙齿牙釉质脱矿发生率和脱矿程度差异均无统计学意义（P〉0．05）。矫治后氟化钠糊剂组牙釉质脱矿率为8．9％，含氟牙膏组为9．0％，对照组为15．6％，两种氟处理组其脱矿率明显低于对照组，差异有统计学意义（P〈0．001）。两种氟处理组发生1度脱矿的牙数高于对照组（P〈0．05），发生3度脱矿的牙数低于对照组（P〈0．05），3组发生2度脱矿的牙数差异无统计学意义（P〉0．05）。氟化钠组和含氟牙膏组EDI小于对照组（P〈0．001），而两种氟处理组间的脱矿率和EDI差异无统计学意义（P〉0．05）。结论正畸治疗中配合使用氟化物处理牙面，可预防牙釉质脱矿的发生。     

五倍子对釉质抗酸蚀作用的实验研究

目的：观察中药五倍子对釉质抗酸蚀作用的效果。方法：采用500g/L五倍子水浸剂为实验组，去离子水为阴性对照，20g／L氟化钠为阳性对照，对60个正常离体牙釉质表面进行处理，制备人工龋模型，用硬组织切片机制备100μm原切片，通过显微放射照射系统观察测量五倍子对釉质的抗酸蚀作用效果。结果：500g／L五倍子水浸剂组较去离子水对照组脱矿少（P〈0．05），与20g／L氟化钠对照组相比无显著差异（P〉0．05）。结论：500g／L五倍子水浸剂可明显增强釉质抗酸蚀能力，其效果与20g／L氟化钠相当。     

氟化微量元素制剂对牙釉质脱钙影响的实验研究

目的：比较氟化微量元素制剂对酸蚀下牙釉质脱钙的抑制作用,为找到低毒高效的防龋制剂提供依据。方法：牙釉质样本分别经含相同氟浓度的5种氟化微量元素制剂（氟化锌、氟化镧、氟化亚锡、氟化锶、氟钼酸铵）及氟化钠处理后酸蚀,甲基麝香草酚蓝法检测酸蚀液中钙浓度的变化。结果：氟化钠及氟化微量元素均有抑制酸蚀下釉质脱钙的作用（p〈0．05）;其中氟化亚锡作用最为明显,与氟化钠等比较有显著性差异（p〈0．01）。结论：锡可明显提高氟化物的防龋生物活性,在抑龋防龋方面,氟化微量元素有广泛的应用前景。     

氟化微量元素制剂对牙釉质显微硬度变化影响的实验研究

目的：比较氟化微量元素制剂对酸蚀下牙釉质显微硬度降低的抑制作用,为找到低毒高效的防龋制剂提供依据。方法：牙釉质样本分别经含相同氟浓度的5种氟化微量元素制剂（氟化锌、氟化镧、氟化亚锡、氟化锶、氟钼酸铵）及氟化钠处理后酸蚀,MH-5型显微硬度计测量牙釉质酸蚀前后显微硬度,观察牙釉质显微硬度的变化。结果：氟化钠、氟化锌、氟化锶、氟化亚锡、氟化镧、氟钼酸铵均有抑制酸蚀下釉质显微硬度降低的作用,其中氟化亚锡对酸蚀下牙釉质显微硬度降低的抑制作用明显强于氟化钠（P〈0．05）。结论：含锡氟化物可显著提高牙釉质的抗酸能力,在抑龋防龋方面,氟化微量元素拥有广泛的应用前景。     

氟化钠涂膜在正畸临床防脱矿和龋坏的应用研究

目的 :研究氟化钠涂膜对正畸临床固定矫治器治疗中产生的牙釉质脱矿或龋坏的预防作用。方法 :170例采用固定矫治器进行治疗的错畸形患者 ,85例做为处理组 ,在托槽粘着后立即在托槽周围的牙面上涂布氟化钠涂膜 ,以后每三个月涂布一次 ;另 85例做为对照组 ,在正畸治疗中托槽周围的牙面不做任何特殊处理。结果 :处理组患者牙釉质表面脱矿发生率 3.7% ;对照组 16 .3%。经统计学处理两组间有显著性差异 (P <0 .0 5 )。结论 :在口腔正畸使用固定矫治器治疗时 ,配合使用氟化钠涂膜对预防正畸治疗中产生的牙釉质脱矿或龋坏是有效的。     

Er, Cr: YSGG激光与氟化物联合应用对牙体硬组织脱矿的影响

目的：体外研究Er，Cr：YSGG激光与氟化物联合应用对牙体硬组织抗酸性的影响。方法：标本随机分成4组，分别为对照组，激光组，氟处理组，激光＋氟组，进行不同处理后，0．1mol／L乳酸（pH4．8）脱矿24h，原子吸收分光光度计检测脱矿液中溶解的钙离子浓度，能谱分析仪进行氟原子含量分析，扫描电镜观察牙釉质和牙本质表面超微结构的变化。结果：激光组、氟处理组、激光＋氟组溶解的钙离子浓度都明显降低，与对照组有显著性差异（P〈0．05），但是激光＋氟组钙离子浓度仅略低于激光组、氟处理组，与其无显著性差异（P〉0．05）；氟含量的测定仅在氟处理组牙釉质和牙本质标本有氟峰出现；扫描电镜观察见，激光组：表面不平呈鳞片状、峭壁状，无玷污层，釉质结构清晰可见，牙本质小管开放，无熔融、炭化等热损伤的表现；氟化钠组：表面有大量玷污层和碎屑，并可见到许多小颗粒沉积在牙釉质和牙本质表面；激光＋氟组：表面结构与激光组相似，未见颗粒沉积。结论：Er，Cr：YSGG激光与氟化物无联合效应，其机制仍需进一步的研究与探讨。     

低浓度钙离子对抗橙汁牙釉质酸蚀作用初探

[摘要]目的：探讨添加低浓度钙离子对橙汁酸蚀牙釉质的影响。方法：45颗离体前磨牙随机分为无添加组、钙离子加强组,空白对照组3组,每组15颗,分别浸泡于橙汁、加钙橙汁（0．4g／L乳酸钙）和去离子水中25h,每5h换液;使用电子酸度计测定每组液体pH,使用激光荧光诊断仪对釉质脱矿程度进行定量分析。结果：无添加组和钙离子加强组离体牙实验后荧光值均显著高于空白对照组（P〈0．05）,钙离子加强组离体牙实验后荧光值显著低于无添加组（P〈0．05）。结论：添加钙离子可显著对抗橙汁对牙釉质的酸蚀作用。     

奥乐V护牙剂对早期釉质龋再矿化作用的研究

目的 观察奥乐V护牙剂对早期釉质龋的再矿化作用。方法 将50个牛牙釉质块建立人工龋模型后随机分为5组：奥乐V护牙剂组、GC护牙素组、氟化钠（NaF）组、奥乐V护牙剂+NaF组、去离子水（DDW）组,分别进入 pH循环模型。采用显微硬度计测定各组标本脱矿前和pH循环后的釉质表面硬度值,扫描电镜观察各组再矿化后釉 质表面形态结构的改变。结果 各实验组经再矿化处理后其表面显微硬度均明显提高（P<0.001）,奥乐V护牙剂组再矿化后其表面显微硬度低于NaF组（P<0.001）,但与GC护牙素组间差异无统计学意义（P>0.05）;再矿化后奥乐V护牙剂组釉质表面有较大颗粒沉积。结论 奥乐V护牙剂具有促早期人工釉质龋再矿化的作用。     

柚皮苷对早期釉质龋再矿化的影响

目的 研究不同浓度的柚皮苷溶液对早期釉质龋再矿化的作用。方法 通过体外脱矿方法建立人前磨牙早期釉质龋模型,利用不同浓度的柚皮苷溶液作为实验药物,氟化钠（NaF）和去离子水（DW）分别为阳性对照和阴性对照,对样本进行再矿化处理。用电子探针观察和分析釉质表面脱矿前、后的图像变化及钙磷比值。结果 电子探针结果显示,去离子水组釉质表面呈典型的脱矿表现,为蜂窝状疏松结构;NaF组可形成均匀球形沉积区;不同浓度柚皮苷溶液组可见不规则沉积物覆盖于脱矿后釉质的蜂窝状表面,并且随着浓度的升高,沉积物由疏松逐渐变为致密。实验组钙磷比值低于NaF组（P＜0.05)。1、10、20和50 mg/mL柚皮苷溶液组的钙磷比与DW组相似,差异无统计学意义;而100 mg/mL柚皮苷溶液组与1 mg/mL柚皮苷溶液组、10 mg/mL柚皮苷溶液组、和DW组相比有统计学意义（P＜0.05)。结论 不同浓度的柚皮苷溶液可促进早期釉质龋的再矿化,其作用效果随着浓度的升高而增强。     

Effect of 0.02% NaF solution on enamel demineralization and fluoride uptake by deciduous teeth in vitro

The application of 0.02% NaF solution on teeth with a cotton swab instead of brushing with fluoride dentifrice has been suggested for young children to reduce the risk of dental fluorosis, but its anticariogenic effect has not been evaluated. Thus, we studied the in vitro effect of 0.02% NaF solution on enamel demineralization and fluoride uptake in deciduous teeth; non-fluoride dentifrice and fluoride dentifrice (1.100 mug F/g) were used, respectively, as negative and positive controls. The treatment with fluoride dentifrice was more effective in reducing enamel demineralization (p < 0.05) and on fluoride uptake by the enamel (p < 0.05) than the non-fluoride dentifrice and the 0.02% NaF solution. Data suggest that the alternative use of 0.02% NaF solution instead of fluoride dentifrice should be reevaluated especially if dental caries are to be controlled.     

Effect of calcium in model plaque on the anticaries activity of fluoride in vitro.

The uptake of calcium by a polysaccharide (agarose) gel used as a model for plaque from a two-step treatment (consisting of a calcium rinse followed by a fluoride treatment) and the effect of the deposited calcium in model plaque on caries lesion formation in enamel were determined. Calcium uptake was measured by treatment of the model plaques with [45Ca]-CaCl2 solutions with or without NaF. A two-step treatment consisting of calcium followed by fluoride produced a 100% increase in calcium content of model plaque, presumably due to the formation of CaF2, compared with a treatment with artificial saliva followed by calcium alone. The effects of these increased plaque minerals on caries lesion formation were studied by subjecting model-plaque-covered enamel blocks to a cyclic demineralization-remineralization treatment. Artificial-plaque-covered enamel blocks were treated daily with 180 ppm calcium for ten min, then 100 ppm fluoride for ten min, followed by demineralization for 16 h, and finally, remineralization for seven h and 40 min. After five days, the blocks were sectioned, and lesion formation was determined by microradiography-microdensitometry. Artificial plaque treated with a calcium rinse followed by a fluoride rinse reduced lesion size by 90%, compared with a 68% reduction by a fluoride rinse alone. When the experiment was repeated with a simulated pre-brush calcium rinse (180 ppm calcium) followed by a fluoride dentifrice suspension (110 ppm fluoride), lesion size was reduced by 46%, compared with a 32% reduction by the fluoride dentifrice suspension alone.     

五倍子提取液对牙本质龋损时胶原蛋白分解的影响

目的：评价五倍子提取液在牙本质龋损中对胶原分解的影响。方法；乳酸胶体系统致牙本质龋，20ml/L氟化钠，五倍子提取液，380ml/L氟化双氨银，去离子水4组试剂分别处理，再次脱矿及I型胶原酶牙本质基质，氯胺－T法对各组胶原分解量进行分析。结果：五倍子组和380ml／L氟化双氨银组对I型胶原酶分解胶原均有显著抑制作用（P＜0．01），且五倍子组明显优于380ml/L氟化双氨银组的抑制胶原分解作用（P＜0．01），结论：五倍子能抑制胶原分解，对脱矿的进一步进行产生影响，从而使牙本质龋的进展受到抑制。     

Effect of an anticalculus dentifrice on lesion progression under pH cycling conditions in vitro

The aim of the present study was to examine a sodium fluoride anticalculus dentifrice product containing soluble pyrophosphate for its ability to promote remineralization and/or inhibit demineralization of dental enamel in a pH cycling model in vitro. Enamel crowns with windows were subjected to 14 days of alternating demineralization and remineralization periods at 37 degrees C. Teeth were immersed 5 min daily in one of the test dentifrice systems (1:3 slurry in deionized water) between the demineralization and remineralization cycles. Test dentifrices included (1) sodium fluoride (NaF; 1,100 ppm F)/silica abrasive (Crest) and (2) NaF (1,100 ppm F) with 3.3% soluble pyrophosphate/silica abrasive (Crest Tartar Control). Controls included a placebo dentifrice (silica abrasive) with no added fluoride and a group which received no treatment at all, i.e., demineralization/remineralization only. Overall, both of the NaF dentifrices were very effective in limiting in vitro caries progression and were not significantly different from each other. Inclusion of pyrophosphate in the NaF dentifrice did not affect the net outcome of the cycling demineralization/remineralization processes which is in agreement with recent clinical and in situ studies of these products.     

局部运用氟制剂抑制牙本质脱矿的体外研究

目的本实验评估体外脱矿环境中几种氟制剂对牙本质的脱钙作用。方法20个标本随机分成5组:0.1%氟保护漆组,0.5%氟保护漆组,0.6%氟化泡沫组,1.23%氟化泡沫组,空白对照组。用钙体外临床诊断试剂盒检测龋蚀液中Ca2 浓度值,计算出每组在各时间点牙本质钙溶出的总量。并将标本制成磨片,在体视显微镜下观察龋损情况。结果氟制剂组抑制钙溶出效果明显优于空白对照组,氟保护漆组优于氟化泡沫组,氟保护漆组之间无显著性差异,氟化泡沫组之间无显著性差异。结论各种氟制剂均有防止牙本质脱钙作用,0.1%氟保护漆抑制牙本质脱钙作用最显著。     

Long-term retention of TiF4 and SnF2 after topical application to dentin in dogs

As part of an evaluation of the potential of topical application of TiF4 in the prevention or arrest of root caries, the longevity of the titanium-rich glaze and the long-term retention of titanium and fluoride in exposed dentin surfaces were examined in dogs. For comparison, the effect of fluoride in combination with another cation, tin, was studied as well. Facets of exposed dentin were prepared in two beagles and treated for 1 or 4 min with either a TiF4 or an SnF2 solution (1.1 M F, native pH). After 3, 7, or 21 wk, the experimental surfaces were analyzed for fluoride, titanium, tin, and calcium using an electron microprobe. Dentin surfaces treated with TiF4 for 1 min showed fluoride concentrations ranging from less than 0.15% to 1.03%, while those treated for 4 min with SnF2 showed values from 0.22% to 1.28%. The calcium analyses revealed partial surface demineralization in one half of the SnF2-treated specimens, while this was a rare finding in the TiF4 group. The findings show that a brief application of TiF4 to exposed dentin results in approximately the same increase in fluoride content as a 4-min application of SnF2, with, however, less surface demineralization. In addition, the presence of a surface glaze may impart an added benefit to the use of TiF4 as a topical agent in the prevention of root caries.