氟涂料预防正畸治疗中釉质脱矿的实验研究

目的　明确氟涂料对釉质脱矿进程的抑制效果。方法　研究分两组 ,实验组釉质表面覆盖氟涂料 ,对照组釉质表面暴露。经短期人工龋后 ,用偏振光显微镜观察托槽周围釉质脱矿病损的分布并测量病损体部深度。结果　对照组全部样本均出现较明显的釉质脱矿 ,病损体部的平均深度为 4 8.8± 15 .1微米 ,实验组中只有少数样本出现孤立的脱矿病损 ,其余样本没有发生明显的脱矿。结论　氟涂料对短期釉质脱矿的抑制作用较明显 ,可以成为正畸治疗中釉质脱矿的预防手段之一。     

氟化物涂膜对正畸固定矫治中牙釉质脱矿影响的SEM研究

目的：采用扫描电镜（SEM）观察氟化物涂膜对抑制离体牙牙釉质脱矿及促进再矿化的功效。方法：选择因正畸需要拔除的前磨牙15颗,经37％磷酸处理,制备人工釉质脱矿标本,并用氟化物涂膜进行表面处理。采用SEM对标本脱矿前（对照组）,脱矿后（脱矿组）以及氟化物涂膜治疗后（治疗组）的表面形貌进行观察分析。结果：对照组与脱矿组之间、脱矿组与治疗组之间形态学存在显著差异,而对照组与治疗组之间形态学差异相对较小。结论：氟化物涂膜可有效改善釉质脱矿后的牙齿脱矿形貌。     

含氟涂料和含氟牙膏对釉面再矿化和抗酸作用的实验研究

目的：观察含氟涂料与含氟牙膏对釉质表面再矿化和抗酸作用。方法：取牛恒切牙制备釉质片;统一酸蚀脱矿后随机分为4组（n＝3）;分别为生理盐水（A组对照）、Duraphat含氟涂料（B组）、Fluor Protector含氟涂料（C组）、含氟牙膏规律处理（D组）;处理期间标本置于人工唾液孵育2周;再次酸蚀;各阶段均用显微硬度仪测定釉面显微硬度、扫描电镜观察釉面,图像分析电镜下釉面微孔隙面积差异;统计分析。结果：首次酸蚀后釉面明显脱矿。分组处理2周,A组釉面再矿化不明显;B组和C组釉面形成涂料保护层;D组釉面可见明显再矿化。再次酸蚀后：A组和D组显微硬度下降,B组和C组涂料保护层有明显抗酸作用。再次酸蚀后,A组和D组釉面微孔隙面积增加（P＜0．05）,但D组小于A组（P＜0．05）;B组、C组无显著变化（P＞0．05）。结论：含氟涂料在釉面形成保护层,具有抗酸蚀和促进釉面再矿化作用;含氟牙膏能促进脱矿釉面再矿化,抗酸作用较弱。     

氟保护漆对青少年固定正畸中釉质脱矿的影响

目的 探讨氟保护漆对青少年正畸患者固定矫治后釉质脱矿发生率的影响。方法 将80例16岁以下青少年固定正畸矫治患者随机分成2组：对照组40例（721颗）,对患者及家长进行口腔健康教育,不涂氟;实验组40例（742颗）,除了对患者和家长宣教外,戴用固定矫治器时及正畸期间每6个月用氟保护漆处理牙面。临床观察2年,对粘接托槽的牙齿观察其脱矿程度。结果 实验组中706颗牙脱矿指数为0,出现脱矿的有36颗,脱矿率为4.85%,未出现脱矿指数大于1的患牙。对照组中有604颗牙脱矿指数为0,出现脱矿的有117颗,脱矿率为16.23%,其中脱矿指数大于1的患牙有18颗。两组间差异有统计学意义（P<0.05）。结论 固定正畸患者戴用固定矫治器时及矫治期间使用氟保护漆能有效预防正畸牙釉质脱矿。     

Influence of carbamide peroxide on enamel fluoride uptake

OBJECTIVE: Aim of the study was to evaluate the influence of carbamide peroxide (CP) on enamel fluoride uptake by comparing enamel fluoride uptake from a 1% amine fluoride (AmF) gel with the fluoride acquisition from a 10% carbamide peroxide agent supplemented with 1% AmF. MATERIALS AND METHODS: Three enamel cylinders (4mm in diameter) were prepared from the buccal surfaces of 60 bovine incisors. One sample of each tooth was used for determination of baseline fluoride content of the respective tooth. The two remaining samples were allocated to the experimental series 1 or 2, respectively. Each series consisted of five experimental groups (A-E, n=12) and differed with respect to the length of the treatment period with the gels (A-D). The experimentally designed gels (pH 5.5) used in the study were as follows: A (10% CP), B (10% CP, 1% F(-) as AmF), C (1% F(-) as AmF), D (no CP, no F(-)) and were formulated on the same basis. The enamel samples were covered for 4h with the respective gel at 37 degrees C and were then transferred to artificial saliva for 20 h (series 1). The samples of group E served as controls and were not treated with a gel. In series 2, treatment with the gels and storage in saliva was conducted seven times. Finally, the samples were assessed for KOH-soluble and structurally bound fluoride. RESULTS: Only the enamel samples treated with the fluoridated bleaching gel (group B) and with the amine fluoride gel (group C) exhibited significant fluoride acquisition. Thereby, both gels showed significantly lower uptake in series 1 as compared to series 2. Both KOH-soluble and structurally bound fluoride acquisition was significantly higher in group C than in group B. CONCLUSION: Treatment with a carbamide peroxide gel supplemented with amine fluoride causes less fluoride acquisition in enamel than a pure amine fluoride gel. Under the conditions of the study, it is assumed that carbamide peroxide seems to influence enamel fluoride uptake.     

Efficacy of CPP-ACP fluoride varnish applied with and without acid etching in preventing enamel demineralization compared to light-curable fluoride varnish

ObjectivesTo compare efficacy of casein phosphopeptide (CPP)–amorphous calcium phosphate (ACP) fluoride varnish and light-curable resin modified glass ionomer fluoride varnish (FV) in preventing white spot lesions and evaluating acid etching prior to CPP-ACPFV application on its efficacy.Materials and MethodsMolars and premolars were transected and halves divided into four groups (n = 18/group): (1) resin-modified glass ionomer FV: etched and Clinpro-XT varnish (3M ESPE, Pymble, New South Wales, Australia) application; (2) CPP-ACPFV: MI varnish (GC America, Alsip, IL) application; (3) Etch+CPP-ACPFV: etched and MI varnish application; (4) Control: etched and no surface treatment. To simulate 12 weeks in an intraoral environment, samples were subjected to thermocycling, brushing, and pH cycling. Enamel surface microhardness was evaluated at baseline and after the simulated 12 weeks. Representative samples were also assessed using scanning electron microscopy (SEM).ResultsAt baseline there was no significant difference in microhardness among groups. After the simulated 12 weeks, all groups showed significant within-group differences (P < .001). Control showed the highest percentage loss of surface microhardness (89%), followed by CPP-ACPFV (58%), RMGIFV (51%), and Etch+CPP-ACPFV (24%). The control group had a significant decrease in microhardness compared to all experimental groups (P < .001). No difference was found between the RMGIFV and CPP-ACPFV varnish groups. The Etch+CPP-ACPFV group had significantly less decrease in microhardness compared to the RMGIFV (P < .001) and CPP-ACPFV groups (P < .001). With SEM, control samples showed signs of enamel surface damage, while experimental groups showed spherical particles on a relatively intact surface.ConclusionsRMGIFV and CPP-ACPFV are effective in reducing enamel demineralization. Acid etching the enamel surface prior to CPP-ACPFV varnish application increased its efficacy.     

氟涂料用于固定矫治后釉质脱矿再矿化治疗的效果

目的评价氟浓度为2.26 mg/mL的氟涂料应用于正畸固定矫治后釉质脱矿再矿化治疗的临床效果。方法对正畸固定矫治结束并拆除托槽的患者进行牙釉质脱矿状况检查,选择符合纳入标准的110例受试者,随机分为2组,试验组在脱矿牙面上涂布氟涂料,对照组在脱矿牙面上涂布蒸馏水,每个月1次,持续6个月,在拆除托槽当天（基线）和拆除托槽3个月、6个月分别对唇颊面釉质脱矿区域进行临床视诊检查,使用临床视诊指数进行评分。结果基线、3个月、6个月时试验组的视诊指数分别为（2.22±0.42）分、（2.18±0.43）分、（2.15±0.41）分;对照组的视诊指数分别为（2.15±0.36）分、（2.14±0.38）分、（2.14±0.38）分。基线（t=2.470,P=0.228）、拆除托槽3个月（t=0.651,P=0.516）及6个月（t=0.149,P=0.882）试验组与对照组的差异均没有统计学意义。试验组的临床视诊指数在拆除托槽3个月、6个月与基线比较差异均有统计学意义（P＆lt;0.05）,但第3个月与第6个月的差异没有统计学意义（t=1.860,P=0.083）。结论应用2.26 mg/mL的氟涂料对固定矫治后出现的釉质脱矿进行再矿化治疗后,牙釉质脱矿程度有所降低,但再矿化效果不够显著。     

玻璃离子保护膜与氟保护漆对牙釉质脱矿的预防和再矿化作用

目的: 比较玻璃离子保护膜与氟保护漆对牙釉质脱矿的预防和再矿化作用。方法: 选择122颗正畸减数拔除的前磨牙,制成釉质块,随机选择2个,进行扫描电镜（SEM）观察,其余用于两部分实验。①釉质脱矿预防实验 （实验A）—选择60个釉质块,随机分为3组（n=20）,分别使用玻璃离子保护膜（A1组）、氟保护漆（A2组）,对照组（A3组）不予处理;②釉质再矿化实验（实验B）—选择60个釉质块,预脱矿72 h后,随机分为3组(B1、B2、B3,n=20),处理方法同预防釉质脱矿各组。实验A、B共6组样本均经人工脱矿液和人工唾液交替pH循环处理30 d。采用SEM观察釉质表面形貌,显微硬度计测定釉质表面显微硬度（SMH）变化,X线能谱分析仪分析釉质表面钙磷比。采用SPSS 26.0软件包对数据进行统计学分析。结果: 釉质脱矿预防实验,未作处理的牙釉质表面平坦、均匀,A1组釉质表面基本完整,A2组釉质表面可见大量片状沉积物,A3组呈现典型的脱矿导致的蜂窝状结构。各组间ΔSMH两两比较,A1组A2组>A3组(P<0.05)。釉质再矿化实验,SEM结果显示,B1、B2组均有沉积物附着于釉质表面,B3组釉质表面凹凸不平,呈蜂窝状。各组间ΔSMH两两比较,B1组>B2组>B3组(P<0.05)。钙磷比值依次为B1组>B2组>B3组(P<0.05)。结论: 玻璃离子保护膜和氟保护漆均可预防和治疗牙釉质脱矿,玻璃离子保护膜由于其耐磨、持久,具有更好的保护和再矿化作用。     

含钙的氟化钠溶液对牙釉质中氟浓度的影响

目的 :观测牙釉质酸蚀后不同时间点的氟离子释出量 ,评价含钙的氟化钠溶液对牙釉质抗酸溶解性作用的效果。方法 :选取釉质完好的新鲜人牙 75个 ,随机分为 3组 ,分别用含相等氟离子的 0 .5 %NaF溶液和 0 .5 %NaF+2 %CaCl2 溶液及去离子水处理 8h后 ,所有样本浸泡于乳酸凝胶中 ,观察第 1、3、7、14、36h酸蚀液中牙釉质释出的氟离子含量。结果 :0 .5 %NaF +2 %CaCl2 溶液组较 0 .5 %NaF组在不同时间点释出的氟含量有统计学差异 ,两组与对照组相比氟离子浓度明显增加 (P <0 .0 0 1)。结论 :含氟溶液可以增强牙釉质的抗酸能力 ,钙离子能延长氟离子的作用时间 ,增强含氟溶液的抗酸脱矿能力     

两种氟防龋涂膜材料的释氟性及抗脱矿能力的研究

目的 比较两种氟防龋涂膜材料的释氟性及其提高釉质的抗脱矿能力。方法 将两种市售的FQ氟涂膜和多乐氟涂膜分别涂覆于20 mm×20 mm的方形聚酯塑料载片表面，每个聚酯塑料载片浸于20mL去离子水中，分别于浸水后3 h、6 h、12 h及24 h测定氟离子浓度，计算释氟率；扫描电镜观察氟涂膜表面形貌。制备5 mm×5 mm×3 mm的牛切牙釉质块，自凝树脂包埋后表面打磨抛光，测定初始表面显微硬度(SMH0)，在釉质块表面涂覆氟涂膜，浸水12 h，然后去除氟涂膜，对釉质块进行pH循环脱矿，7天后测定釉质块表面显微硬度(SMH1)，计算脱矿后釉质表面显微硬度下降率，设立阳性对照和阴性对照。结果 FQ氟涂膜和多乐氟3 h、6 h、12 h、24 h释氟率分别为(2.73±0.27)%、(3.19±0.05)%、(3.58±0.19)%、(3.63±0.08)%和(0.16±0.02)%、(0.34±0.03)%、(0.43±0.03)%、(0.48±0.03)%；经过pH循环脱矿后，应用过氟涂膜的釉质表面显微硬度下降率显著低于未用氟涂膜的釉质（85.95±3.50）%,FQ氟涂膜和多乐氟的硬度...     

Increased fluoride uptake and acid resistance by CO2 laser-irradiation through topically applied fluoride on human enamel in vitro

OBJECTIVES: The aim of the current in vitro study was to evaluate the effect of CO(2)-laser treatment immediately after applying amine fluoride solution on enamel. It was hypothesized that such a treatment would increase enamel fluoride uptake, and reduce dissolution rate and thermal surface alterations. METHODS: Fluoride uptake was determined in 40 human enamel sections randomly assigned to four groups (n=10), which were either left untreated (1), exposed to a 1% amine fluoride solution for 15s without irradiation (2), irradiated for 15s with a continuous-wave carbon dioxide laser (3), or laser-treated for 15s through the amine fluoride solution applied immediately beforehand (4). Fluoride uptake was determined with an ion selective electrode after acid dissolution of the specimens (surface and subsurface layers). For the determination of acid resistance, another 40 enamel sections were treated according to the above protocol. Acid resistance was determined in surface and subsurface layers by measuring eluted calcium upon 3% lactic acid exposure with atomic absorption spectrometry. Enamel surface alterations after laser irradiation were monitored using scanning electron microscopy. RESULTS: Laser irradiation through the fluoride solution led to significantly higher fluoride contents in the surface enamel layer compared to fluoride treatment alone or laser treatment alone (p=0.002). Laser treatment with or without fluoride resulted in an increased acid resistance of enamel specimens. Fewer surface alterations were observed upon SEM examination of specimens irradiated through the amine fluoride solution compared to counterparts treated with laser only. CONCLUSIONS: CO(2) laser light application through an amine fluoride solution may be useful and effective in the prevention of caries.     

Enamel and dentine remineralization by nano-hydroxyapatite toothpastes

Objectives

This in vitro study evaluated the effects of nano-hydroxyapatite (n-HAp) toothpastes on remineralization of bovine enamel and dentine subsurface lesions.

Methods

Specimens were demineralized, randomly divided into five groups, and exposed to an aqueous remineralizing solution for two and five weeks (37 °C). Brushing procedures were performed with the respective toothpaste/storage solution slurry twice daily (2 × 5 s; total contact time of the slurries 2 × 120 s/d): storage in remineralizing solution only (0); additional brushing with B (20 wt% zinc carbonate nano-hydroxyapatite, ZnCO₃/n-HAp); BS (24 wt% ZnCO₃/n-HAp); E (0.14 wt% amine fluoride); or A (7 wt% pure n-HAp). Differences in mineral loss (ΔΔZ) before and after storage/treatment were microradiographically evaluated.

Results

Dentine groups 0, B, BS, and A showed significantly higher ΔΔZ values compared to E (p < 0.05; ANOVA). Enamel ΔΔZ values of group A were significantly higher compared to group E (p < 0.05), whilst no significant differences of these groups could be observed compared to 0, B, and BS (p > 0.05).

Conclusions

With the in vitro conditions chosen, toothpastes containing n-HAp revealed higher remineralizing effects compared to amine fluoride toothpastes with bovine dentine, and comparable trends were obtained for enamel.     

不同浓度氟泡沫对牙釉质表面显微硬度的影响

目的：观察不同浓度氟泡沫对脱矿牙釉质表面显微硬度值的影响。方法：将牙釉质块随机分为A，B两组，脱矿30min后在两组牙釉质表面分别涂布0．9％中性氟化钠氟泡沫和1．23％酸性氟磷酸盐氟泡沫4min，并在人工唾液中浸泡30min,24h后测定牙釉质表面显微硬度值，结果：两组不同浓度氟泡沫涂布后牙釉质表面显微硬度值均有显著提高，人工唾液浸泡30min和24h，涂布1．23％酸性氟磷酸盐氟泡沫组的牙南表面显微硬度值均高于0．9％中性氟化钠氟泡沫组，统计学检验30min时有显著差异，24h无差异。结论：两种浓度的氟泡沫均可使牙釉质表面显微硬度显著提高，1．23％酸性氟磷酸盐氟泡沫影响效果优于0．9％中性氟化钠氟泡沫。     

含氟充填材料释氟吸氟和再释氟的研究

目的 为了研究含氟充填材料能否长期稳定释放氟而发挥抗龋效能,本文观察了玻璃离子水门汀和含氟复合树脂在用含氟牙膏处理前后两个时期的释氟情况。方法 第一阶段,将玻璃离子水门汀和含氟复合树脂各６个标本,分别浸泡于去离子水中,测定其在不同时间氟的放量;第二阶段。用含氟牙膏处理各标本后,再测定其在不同时间氟的释放量。结果 当这两允填材料释氟水平降低后,用含氟牙膏处理,琪 释放量明显回升     

不同浓度的含氟涂料对人牙釉质抗酸性的影响

目的：确定4种浓度的含氟涂料对人牙釉质抗酸性的影响。方法：采用22000ppm,10000ppm,5000ppm及2200ppm等4种不同浓度的含氟涂料处理离体人牙釉质后经脱矿实验，然后测量酸蚀液中钙的溶出量，并用激光荧光诊断仪对人工龋损进行定量诊断。结果：22000ppm组与10000ppm组的抗酸性无差别，而其余各组之间均有差别。结论：22000ppm及10000ppm的含氟涂料抑制牙釉质脱矿的效果比5000ppm及2200mmp的含氟涂料好，而将22000ppm的含氟涂料浓度降至10000ppm，并不影响它的防龋效果，因此，在临床应用时，可以考虑适应降低含氟涂氟浓度以提高安全性。     

Effect of a 4% titanium tetrafluoride (TiF4) varnish on demineralisation and remineralisation of bovine enamel in vitro

OBJECTIVES: This in vitro study assessed the effect of a 4% TiF4 varnish on demineralisation and remineralisation of sound enamel and artificial carious enamel lesions, respectively. METHODS: Bovine sound and carious enamel (n=110) were randomly allocated to each type of varnish: Duraphat-D (NaF, 2.26%F, pH 4.5, Colgate-Brazil, n=30), Duofluorid-F (NaF, 2.71%F, pH 8.0, FGM-Brazil, n=30), TiF4-T (2.45%F, pH 1.0, FGM-Brazil, n=30) and no-fluoride-P (FGM-Brazil, pH 5.0, n=20). For the formation of artificial enamel caries, half of the blocks were immersed in 32 mL buffer acetate solution (16 h), whereas the other half was maintained sound. The varnishes were applied onto the enamel surfaces. Thus, the samples were subjected to pH cycles (37 degrees C) for 7 days. The response variables tested were surface and cross-sectional hardness. Data were tested using Kruskal-Wallis test (p<0.05). RESULTS: All F varnishes significantly reduced demineralisation and increased remineralisation in comparison to placebo. The TiF4 did not significantly reduce the surface enamel softening when compared with the other F varnishes, but it decreased the loss of subsurface hardness to the same extent. In enamel blocks with previous artificial carious lesions, the TiF4 significantly improved the rehardening compared to the other varnishes up to 30 microm depth. CONCLUSIONS: The TiF4 varnish was able to decrease the demineralisation and increase the remineralisation of previously sound and carious enamel, respectively. It was equally effective compared to NaF varnishes on reducing the demineralisation at subsurface, but it was more effective on improving the remineralisation at surface and subsurface.     

Effect of stannous and fluoride concentration in a mouth rinse on erosive tissue loss in enamel in vitro

The aim of this in vitro study was to investigate the influence of stannous and fluoride ion concentrations in various experimental solutions on erosion progression in enamel. Human enamel specimens were subjected to a cyclic de- and remineralisation procedure for 10 days, with six demineralisation periods per day, of 5 min each. Erosive demineralisation was performed with 0.05 M citric acid (pH 2.3). Except in the control group, specimens were treated for 2 min with test solutions after the first and the sixth demineralisation. Test solutions were: 1500 mg/L F⁻ groups: group 1: 2800 mg/L Sn²⁺; group 2: 2100 mg/L Sn²⁺; group 3: 1400 mg/L Sn²⁺; group 4: 700 mg/L Sn²⁺; 1000 mg/L F⁻ groups: group 5: 2100 mg/L Sn²⁺; group 6: 1400 mg/L Sn²⁺. All preparations were adjusted to pH 4.5. Tissue loss was determined profilometrically after the last experimental day. As expected, the greatest tissue loss (μm, mean ± S.D.) was found in the control group (72.6 ± 11.5). All test solutions were able to reduce tissue loss significantly (p ≤ 0.001). The reduction of tissue loss by test solutions depended on the ratio of the tin concentration to the fluoride concentration. Lowest values were obtained by the application of the solutions of group 1 (7.8 ± 2.5) and group 5 (7.6 ± 5.2). Solutions with high concentrations of tin and fluoride are very effective in reducing erosive tissue loss, and their efficacy increased with increasing ratios of tin to fluoride concentrations.     

Effect of fluoride varnish supplemented with sodium trimetaphosphate on enamel erosion and abrasion: An in situ/ex vivo study

Objective

To evaluate the effect of fluoride (F) varnishes supplemented or not with sodium trimetaphosphate (TMP) on enamel erosive wear followed or not by abrasion in situ.

Methods

Ten volunteers were selected and randomly divided into four groups, according to the varnishes tested: placebo (no F or TMP), 5% NaF (positive control), 2.5% NaF and 2.5% NaF/5% TMP. Enamel blocks (n = 4) were mounted in palatal devices and received an application of each test varnish, following a double-blind, crossover protocol. After 6 h, varnishes were completely removed and the blocks were subjected to erosive challenges by ex vivo immersion in citric acid (5 min, 4×/dia, 5 days). Following, half of the blocks were subjected to abrasion by brushing with a placebo dentifrice slurry for 15 s. Enamel wear (μm), surface hardness (SH_f) and cross-sectional hardness (ΔKHN) were assessed after each experimental period. Results were analyzed by ANOVA, Student–Newman–Keuls's test and Pearson correlation coefficient (p < 0.05).

Results

The fluoride varnish supplemented with TMP promoted significantly lower wear and ΔKHN when compared to the other groups after erosive challenges, followed or not by abrasion (p < 0.05). As for (SH_f) the fluoride varnish supplemented with TMP promoted similar results to the 5% NaF product, being significantly higher than the remaining groups after erosive and erosive + abrasive challenges (p < 0.05).

Conclusion

TMP significantly enhanced the effects of F on enamel wear after erosive challenges, followed or not by abrasion.