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1.
Annette Wiegand Dominique Bichsel Ana Carolina Magalhães Klaus Becker Thomas Attin 《Journal of dentistry》2009
Objective
This study aimed to compare the effects 0.5% and 1% sodium, amine and stannous fluoride at different pH on enamel erosion in vitro.Methods
Bovine enamel samples were submitted to a cyclic de- and remineralisation for 3 days. Each day, the samples were exposed for 120 min to pooled human saliva and subsequently treated with one of the fluoride solutions for 3 min: amine fluoride (AmF, 0.5% and 1% F−), sodium fluoride (NaF, 0.5% and 1% F−), each at pH 3.9 and 7.0, and stannous fluoride (SnF2, 0.5% and 1% F−), at pH: 3.9. Additionally, two groups were treated with fluoride-free placebo solutions (pH: 3.9 and 7.0) and one group served as control (no fluoridation). Ten specimens each group were inserted in a so-called artificial mouth and eroded six times daily with hydrochloric acid (pH 2.6) for 90 s each intermitted by exposure to artificial saliva (1 h). After 3 days, enamel loss was analyzed profilometrically and evaluated statistically by ANOVA.Results
Only the acidic 0.5% and 1% SnF2 and 1% AmF solutions were able to reduce erosive enamel loss significantly, while all other solutions and placebos did not differ significantly from the control. Between the acidic SnF2 and the 1% AmF solutions no significant differences could be detected.Conclusion
At the same concentrations, acidic SnF2 and AmF may be more effective than NaF to protect enamel against erosion. 相似文献2.
Objectives
Sn2+ has promising erosion-inhibiting properties in solutions, but little is known about respective effects in toothpastes. In addition, biopolymers might have protecting potential. Aim of this study was to investigate the effects of Sn2+ in toothpastes and of a biopolymer (chitosan) added to a Sn2+ formulation on erosion/abrasion.Methods
Enamel samples were subjected to cyclic erosion procedures (10 days; 0.50% citric acid, pH 2.5; 6× 2 min/day), and brushing (2× 15 s/day, load 200 g) during immersion in slurries (2 min). The toothpastes were NaF formulations (NaF/1, NaF/2, NaF/3) and Sn2+ formulations (NaF/SnCl2, AmF/SnF2, AmF/NaF/SnCl2) and AmF/NaF/SnCl2 + 0.5% chitosan.Declared concentrations of active ingredients in toothpastes were 1400–1450 μg/g F− and 3280–3500 μg/g Sn2+. Negative controls were erosion only and placebo, positive control was a SnF2 gel. Tissue loss was quantified profilometrically, Sn on enamel surfaces was measured by energy dispersive X-ray spectroscopy.Results
Loss values (μm) for erosion only and placebo were 14.4 ± 4.5 and 20.2 ± 3.8, respectively, and 4.6 ± 1.9 for the positive control (p ≤ 0.001 each compared to erosion only). The other loss values were: NaF/1 16.5 ± 3.0, NaF/2 14.0 ± 2.7, NaF/3 12.6 ± 3.9, NaF/SnCl2 14.7 ± 5.1, AmF/SnF2 13.5 ± 4.8, AmF/NaF/SnCl2 12.4 ± 4.2, AmF/NaF/SnCl2 + chitosan 6.6 ± 3.5 (except NaF/1 all p ≤ 0.01 compared to placebo). AmF/NaF/SnCl2/chitosan was more effective than all other toothpastes (p ≤ 0.01 each). Sn on the enamel surface ranged between 1.3 ± 0.3 and 2.8 ± 0.04 wt.% with no obvious relationship with efficacy.Conclusions
The NaF and Sn2+ toothpastes without chitosan exhibited similar anti-erosion and abrasion-prevention effects. The experimental Sn2+ formulation with chitosan revealed promising results similar to those of the positive control.Clinical significance
NaF toothpastes offer a degree of protection against erosion/abrasion, which is likely sufficient for most subjects with average acid exposures. For patients with initial erosive lesions, however, more effective toothpaste is desirable. The combination of Sn2+ and a biopolymer appears promising in this context. 相似文献3.
不同浓度氟泡沫对牙釉质表面显微硬度的影响 总被引:2,自引:0,他引:2
潘瑛 《现代口腔医学杂志》2002,16(2):130-131
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。 相似文献
4.
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. 相似文献
5.
OBJECTIVES: Aim of the study was to investigate the stability of CaF(2)-like precipitates on enamel and dentine under neutral or acidic conditions and to compare in vitro and in situ results. METHODS: Human enamel and dentine specimens were fluoridated (Elmex fluid, 5 min) and subjected to erosive demineralisation (Sprite light: 3/day each; 30 s in vitro, 2 min in situ) or stored under neutral conditions for 4 (in vitro) or 7 (in situ) days. KOH-soluble fluoride was determined using an ion selective electrode. Between the acid attacks, specimens were stored in remineralisation solution (in vitro) or retained in the oral cavity (four volunteers for enamel and dentine each). RESULTS: Initially, high amounts of KOH-soluble fluoride were gained (between 77.9+/-12.3 and 96.0+/-46.4 microg/cm2). Under neutral conditions in vitro, a significant decrease on enamel (16.2+/-5.0 microg/cm2) and dentine (18.6+/-10.5 microg/cm2) was found, which was more severe under acidic conditions (6.3+/-3.0 and 5.1+/-2.1 microg/cm2, respectively). Under in situ conditions, KOH-soluble fluoride was strikingly stable on enamel under neutral (42.3+/-12.6 microg/cm2) as well as under acidic conditions (54.1+/-17.4 microg/cm2). On dentine, the dissolution kinetics of KOH-soluble fluoride was similar to the in vitro conditions, but the loss was less severe (45.3+/-12.9 microg/cm2 under neutral and 8.8+/-6.4 microg/cm2 under acidic conditions). CONCLUSIONS: In vitro, more KOH-soluble fluoride was lost under erosive compared to neutral conditions. The intra-oral environment was considerably protective for CaF2-like precipitates especially on enamel. 相似文献
6.
Wiegand A Laabs KA Gressmann G Roos M Magalhães AC Attin T 《Archives of oral biology》2008,53(6):497-502
OBJECTIVE: This in vitro study aimed to analyse the protective effect of differently concentrated titanium (TiF(4)), zirconium (ZrF(4)) and hafnium (HfF(4)) tetrafluoride on enamel erosion. METHODS: Polished enamel surfaces of 36 bovine crowns were covered with tape leaving 4 enamel windows each 3mm in diameter exposed. The crowns were randomly assigned to six groups (each n=6) and pretreated with 4% TiF(4), 10% TiF(4), 4% ZrF(4), 10% ZrF(4), 4% HfF(4) or 10% HfF(4) for 4 min (first window), 10 min (second window) or 15 min (third window). The fourth window of each crown was not pretreated and served as control. Erosion was performed stepwise with 1% HCl (pH 2) in five consecutive intervals of each 15 s (total 75 s). Enamel dissolution was quantified by colorimetric determination of phosphate release into the acid. For each tooth, cumulative phosphate loss of enamel pretreated with one of the tetrafluoride compounds was calculated as percentage of the respective control and statistically analysed using two-way ANOVA. RESULTS: Enamel erosion was significantly reduced by TiF(4), ZrF(4) and HfF(4) application. Cumulative phosphate loss (mean % of control, 75s erosion) after 4-15 min application was significantly lower for 4% ZrF(4) (7-11%), 10% ZrF(4) (2-6%), 4% HfF(4) (11-9%) and 10% HfF(4) (12-16%) compared to 4% TiF(4) (42-27%) and 10% TiF(4) (54-33%). Only for 4% and 10% TiF(4), phosphate loss decreased with increasing duration of application, but also increased with increasing acid intervals. CONCLUSION: TiF(4), ZrF(4) and HfF(4) might protect enamel against short-time erosion, but protection was more enhanced by ZrF(4) and HfF(4) compared to TiF(4) application overtime. 相似文献
7.
目的 用显微硬度测量法研究氟化物对碳酸饮料酸蚀后的乳牙釉质的再矿化作用.方法 收集临床拔除的滞留第二乳磨牙共16颗,制成牙釉质样本.经碳酸饮料浸泡,每天2次,每次10分钟,共5天后,分为对照组(A组)、2%氟化钠溶液组(B组)、含1.23%氟离子凝胶组(C组)和含低氟过饱和钙磷溶液矿化液组(含氟10ppm)(D组)四组,每组16个牙块.经不同的氟化物处理釉质表面,每天1次,每次2分钟,共5天.分别在酸蚀前、酸蚀后和再矿化后用显微硬度计测定釉质表面硬度.数据使用SPSS10.0统计软件包进行单因素方差分析(ANOVA).结果 饮料酸蚀后的牙釉质表面硬度值明显下降.与对照组相比,经2%氟化钠溶液和1.23%氟离子凝胶组处理后的牙釉质表面硬度值均比处理前显著上升(分别为P=0.031和P=0.017),这两组之间的差异无显著性;矿化液处理后的牙釉质表面硬度值无显著变化(P=0.894).结论 显微硬度测定实验显示高浓度的氟制剂2%氟化钠溶液和含1.23%氟离子凝胶能够显著地促进酸蚀釉质再矿化;低氟浓度矿化液在短时间内对酸蚀釉质再矿化作用不明显. 相似文献
8.
Florian J. Wegehaupt Barbara Solt Beatrice Sener Annette Wiegand Patrick R. Schmidlin Thomas Attin 《Archives of oral biology》2009,54(9):823-829
Objective
To determine the association between KOH-soluble and structurally bound fluoride uptake and the erosion resistance of enamel, respectively. Additionally, the effect of enamel pre-treatment with ethanol before fluoridation was assessed.Methods
Sixty bovine incisors (4 specimens/tooth) were randomly allocated to six groups (A-F). Samples 1 and 2 remained untreated, serving as control at baseline. Pre-treatment of the samples was performed for 5 min with 99% ethanol (groups A, B and C) or physiologic saline (groups D, E and F). Samples 3 and 4 were treated either with 0.5% (groups A and D), 1.0% (groups B and E) or 1.5% (groups C and F) fluoride solution. In samples 1 and 3, uptake of KOH-soluble and structurally bound fluoride was determined. Samples 2 and 4 were used for the determination of acid susceptibility by immersion in 1 ml HCl for 30 s. Calcium release into HCl was assessed by atomic absorption spectroscopy. Differences between the groups were calculated by unpaired t-tests (p < 0.05).Results
Mode of pre-treatment showed no influence on fluoride acquisition. KOH-soluble and structurally fluoride uptake increased with increasing fluoride concentrations. Highest acid resistance was observed after treatment with 1% fluoride solution for both kinds of pre-treatment followed by 1.5% and 0.5% fluoride solution.Conclusion
Dose-dependency was observed for enamel fluoride acquisition but not for acid resistance. 相似文献9.
Cecilia P. Turssi Anderson T. Hara Flávia L.B. Amaral Fabiana M.G. França Roberta T. Basting 《Journal of dentistry》2014
Objectives
This in situ trial study was designed to evaluate whether calcium (Ca) pre-rinse would increase the fluoride (F) rinse protection against enamel erosion.Methods
Fifteen volunteers participated in this split-mouth, 3-phase, crossover design study wearing a palatal appliance containing four sterilized bovine enamel slabs, for 10 days. In the 1st phase, five participants followed protocol A: daily rinse with a Ca lactate (CaL, 150 mmol/L, 1 min), followed by F (NaF 12 mmol/L, 1 min). Other five participants followed protocol B: daily rinse only with F, while the remainders followed protocol C: no rinse (negative control). Appliances were removed from the mouth and one side of the palatal appliance was exposed to a daily erosive challenge (0.05 M citric acid, 90 s); the other side served as control (deionized water – no erosion). In the 2nd phase volunteers were crossed over to other protocol and in the 3rd phase volunteers received the remaining protocol not yet assigned. Specimens were evaluated for surface loss using an optical profilometer.Results
Repeated-measures three-way ANOVA (p = 0.009) and Tukey's test showed that CaL pre-rinse followed by NaF rinse significantly decreased surface loss of enamel when performed prior to an erosive challenge in comparison with the condition in which NaF only was used.Conclusions
Pre-rinse with CaL may increase the protection exerted by NaF against erosive wear. 相似文献10.
A.C. Magalhães F.M. Levy B.M. Souza C.A.B. Cardoso L.P. Cassiano J.P. Pessan M.A.R. Buzalaf 《Journal of dentistry》2014
Objectives
This in vitro study assessed the effect of milk containing different fluoride concentrations on tooth erosion.Methods
Bovine enamel and root dentine specimens were treated with: (1) bovine whole milk with 0 ppm F; (2) 2.5 ppm F; (3) 5 ppm F; (4) 10 ppm F (all after erosion); (5) whole milk with 0 ppm F (before erosion); (6) NaF (0.05% F, positive control, after erosion) or (7) 0.9% NaCl (negative control, after erosion). The specimens were submitted to pH cycles (4× 90 s in soft drink) and treatments for 5 days. The specimens were immersed in the treatment solutions for 1 min (only at the first cycle each day) with further exposition to 1:1 milk:saliva slurry for 10 min. The tooth loss was measured using a contact profilometer and statistically analysed (p < 0.05).Results
Rinsing with milk before erosive challenge significantly reduced tooth loss compared to negative control (67% and 24% reduction in dentine and enamel loss, respectively) and to milk after erosive challenge, only for dentine. The addition of fluoride to milk also reduced tooth loss compared to negative control, but with no significant differences among fluoride concentrations for enamel and dentine (μm), respectively: 0 ppm (3.63 ± 0.04 and 2.51 ± 0.53), 2.5 ppm F (2.86 ± 0.42 and 1.96 ± 0.47), 5 ppm F (2.81 ± 0.27 and 1.77 ± 0.44), 10 ppm F (2.03 ± 0.49 and 1.68 ± 0.59). There was a negative and significant correlation between [F] and the tooth loss.Conclusions
Daily rinse with milk containing F is able to reduce both enamel and dentine erosion in vitro.Clinical significance
Since the prevalence of dental erosion is steadily increasing, rinse with milk or its derivate might be an important strategy to reduce the progression of tooth erosion. 相似文献11.
The aim of this study was to evaluate the effect of mineral supplements to citric acid (1%; pH 2.21) on enamel erosion under controlled conditions in an artificial mouth. From each of 156 bovine incisors one polished enamel sample was prepared. The samples were divided among 13 experimental groups (n=12). In group 1 citric acid only was used (control). In groups 2-10 either calcium, phosphate or fluoride in various low concentrations was admixed to the citric acid. In groups 11-13 the citric acid was supplemented with a mixture of calcium, phosphate and fluoride. For demineralisation the specimens were rinsed with the respective solution for 1 min, immediately followed by a remineralisation period with artificial saliva (1 min). The specimens were cycled through this alternating procedure five times followed by rinsing for 8 h with artificial saliva. The de- and remineralisation cycle was repeated three times for each specimen interrupted by the 8 h-remineralisation periods. Before and after the experiments, the specimens were examined using microhardness testing (Knoop hardness) and laser profilometry. Hardness loss and enamel dissolution was significantly higher for the controls as compared to the remaining groups. Significantly lowest hardness loss for all groups was recorded for group 12 with admixture of calcium, phosphate and fluoride to citric acid. The significantly highest enamel loss was recorded for the controls compared to all other samples. Groups 3 and 4 revealed significantly lower and higher tissue loss compared to the remaining groups (2-13), respectively. The other groups did not differ significantly from each other. Modification of citric acid with calcium, phosphate and fluoride exerts a significant protective potential with respect to dental erosion. However, with the low concentrations applied enamel dissolution could not be completely prevented. 相似文献
12.
Objectives
To investigate the effect of an aqueous sodium fluoride solution of increasing concentration on erosion and attrition of enamel and dentine in vitro.Methods
Enamel and dentine sections from caries-free human third molars were polished flat and taped (exposing a 3 mm × 3 mm area) before being randomly allocated to 1 of 5 groups per substrate (n = 10/gp): G1 (distilled water control); G2 (225 ppm NaF); G3 (1450 ppm NaF); G4 (5000 ppm NaF); G5 (19,000 ppm NaF). All specimens were subjected to 5, 10 and 15 cycles of experimental wear [1 cycle = artificial saliva (2 h, pH 7.0) + erosion (0.3% citric acid, pH 3.2, 5 min) + fluoride/control (5 min) + attrition (60 linear strokes in artificial saliva from enamel antagonists loaded to 300 g)]. Following tape removal, step height (SH) in μm was measured using optical profilometry.Results
When the number of cycles increased the amount of tooth surface loss increased significantly in enamel and dentine after attrition and erosion and for dentine after attrition. Attrition and erosion resulted in greater surface loss than attrition alone after 15 cycles of experimental wear of enamel. 5000 ppm and 19,000 ppm sodium fluoride solutions had a protective effect on erosive and attritional enamel tooth wear in vitro, however no other groups showed significant differences.Conclusions
The more intensive the fluoride regime the more protection was afforded to enamel from attrition and erosion. However, in this study no such protective effect was demonstrated for dentine. 相似文献13.
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. 相似文献
14.
OBJECTIVES: To evaluate the effects of fluoridated bleaching agents and post-bleaching fluoridation treatment on the whitening efficiency and microhardness of bovine enamel. METHODS: Twenty five freshly extracted bovine incisors were cut into halves, embedded and then divided into the following five groups: Group 1, untreated controls; Group 2, treatment with 10% carbamide peroxide (CP) bleaching agent; Group 3, treatment with 10% CP followed by a 0.9% sodium fluoride gel application, Group 4, treatment with 10% CP containing 0.11% fluoride; Group 5, treatment with an experimental bleaching agent consisting of 10% CP and 0.37% fluoride. Groups 2-5 were treated 8h per day for 14 days then immersed in saliva for 2 weeks. Enamel morphology changes were evaluated under SEM on Day 14. Changes in enamel color and microhardness were evaluated on Days 7 and 14, and compared with the baseline data. Additionally, microhardness was determined on post-bleaching Days 21 and 28. RESULTS: After 2 weeks, an erosion pattern was noted on the specimens in Groups 2 and 3. Groups 4 and 5 showed a milder demineralized pattern. All the bleached enamel specimens revealed increased whiteness and overall color value. Groups 2 and 3 showed significantly decreased enamel microhardness compared to their baseline data. The specimens treated with fluoridated bleaching agents showed relatively less reduction in enamel microhardness than those treated with nonfluoridated agents during the bleaching treatment. CONCLUSIONS: The fluoridated bleaching agents produced less demineralization of surface morphology and microhardness. The addition of fluoride did not impede the whitening effect. 相似文献
15.
Annette Wiegand Barbara Hiestand Ana Carolina Magalhães Thomas Attin 《Archives of oral biology》2010,55(3):223-228
Objective
This in situ study aimed to analyse the impact of different tetrafluorides (TiF4, ZrF4 and HfF4) and AmF on erosion and erosion plus abrasion of enamel and dentin.Design
Ten volunteers took part in this crossover and double-blind study performed in 8 phases of each 3 days. In each phase, 2 bovine enamel and 2 dentin specimens were fixed in intraoral appliances. One enamel and one dentin sample were pretreated once with TiF4, ZrF4, HfF4 or AmF (all 0.5 M F) for 60 s, while the other samples remained unfluoridated and served as control. Then, all samples were subjected to either erosion only (4 times/day, 90 s) or to erosion and abrasion (2 times/day, 30 s/sample). Toothbrushing abrasion was performed 90 min after the first and last erosion with an electrical toothbrush and fluoridated toothpaste at 1.2 N. After 3 days, enamel and dentin loss was assessed by profilometry (μm) and analysed by repeated measures ANOVA and paired t-test (p < 0.05).Results
All fluoride solutions reduced enamel and dentin loss significantly compared to the controls. Generally, eroded samples showed less wear than eroded and abraded samples. The protective potential of the fluorides was not significantly different and was only slightly, but mostly not significantly, decreased by abrasion. The protective effect of the fluoride solutions was similar in enamel and dentin.Conclusion
Tetrafluorides and AmF are able to reduce erosion and erosion plus abrasion in situ and are almost equally effective. 相似文献16.
饮料对牙釉质表面硬度的影响的体外实验研究 总被引:1,自引:1,他引:1
目的 本实验用显微硬度测量法,定量研究和评估人离体牙釉质在酸性饮料中的硬度变化,比较牙釉质在饮料中浸泡时间及浸泡频率对釉质表面硬度的影响。方法 实验设人工唾液组(对照组)和可口可乐组、橙汁组,共9组,每组1 0个牙块。浸泡在饮料中1次/天、3次/天、7次/天,均在37℃恒温箱中进行,每次1 0分钟,共进行4天。在0天、2天、4天测量牙釉质表面硬度(韦氏法)。结果 ①对照组实验前后无显著性差异。②可口可乐组1次/天和7次/天在4天的硬度值为1 6 2±5 0和6 8±4 0 ,有显著性差异(P =0 .0 1 ) ;橙汁组1次/天和7次/天在4天的硬度值为2 1 0±6 3和93±34,有显著性差异(P =0 .0 0 1 )。③此外,可口可乐组和橙汁组牙釉质表面的平均硬度从0天(基线值)到2天均有一个急剧的下降过程并持续至第4天(各为0天335±34,2天1 4 3±84 ,4天1 0 4±5 9和0天343±2 8,2天1 85±72 ,4天1 5 4±74 ) ,两饮料组之间无显著性差异。结论 可口可乐和橙汁可使牙釉质表面硬度降低,浸泡的时间和频率起主要作用。这对于儿童合理使用饮料并预防龋齿有临床指导意义。 相似文献
17.
Christiana Murakami Marcelo Bnecker Maria Salete Nahs Pires Corrêa Fausto Medeiros Mendes Clia Regina Martins Delgado Rodrigues 《Archives of oral biology》2009,54(11):997-1001
Objective
To assess the effect of a fluoride varnish and gel on the erosive wear of primary and permanent teeth.Design
Sixty human primary (n = 30) and permanent (n = 30) enamel specimens were randomly assigned to one of the following groups: APF gel (1.23% F), NaF varnish (2.26% F), and control (no treatment). Fluoride gel was applied for 4 min and fluoride varnish for 24 h. Six daily demineralisation-remineralization cycles of 5 min of immersion in a cola drink (pH 2.3) and 30 min in artificial saliva were conducted during 7 days. All specimens were stored in artificial saliva between and after cycles. Surface Knoop microhardness (%SMHC) readings were performed at baseline, 48 h and 7 days. Data were tested using ANOVA and Tukey's tests (p < 0.05).Results
For primary enamel, the mean %SMHC (±SD) after 48 h and 7 days was, respectively: gel (31.0 ± 14.4 and 36.9 ± 7.5), varnish (26.7 ± 9.5 and 38.3 ± 8.7), and control (35.8 ± 8.6 and 45.0 ± 8.6). For permanent enamel, such values were: gel (37.5 ± 7.7 and 27.8 ± 7.5), varnish (31.7 ± 9.6 and 27.4 ± 11.1) and control (48.6 ± 6.4 and 43.1 ± 6.4). In primary enamel, erosion inhibition by fluoride was not significant at 48 h (p = 0.203) and 7 days (p = 0.082). In permanent specimens, both products showed a significant effect (p < 0.001).Conclusions
Both fluoride varnish and gel were able to inhibit erosive enamel loss but mainly in the permanent experimental groups. Primary and permanent enamel substrates reacted differently to both demineralization by a cola drink and remineralization by fluoridated compounds. 相似文献18.
New toothpastes with anti-erosion claims are marketed, but little is known about their effectiveness. This study investigates these products in comparison with various conventional NaF toothpastes and tin-containing products with respect to their erosion protection/abrasion prevention properties. In experiment 1, samples were demineralised (10 days, 6 × 2 min/day; citric acid, pH 2.4), exposed to toothpaste slurries (2 × 2 min/day) and intermittently stored in a mineral salt solution. In experiment 2, samples were additionally brushed for 15 s during the slurry immersion time. Study products were 8 conventional NaF toothpastes (1,400-1,490 ppm F), 4 formulations with anti-erosion claims (2 F toothpastes: NaF + KNO(3) and NaF + hydroxyapatite; and 2 F-free toothpastes: zinc-carbonate-hydroxyapatite, and chitosan) and 2 Sn-containing products (toothpaste: 3,436 ppm Sn, 1,450 ppm F as SnF(2)/NaF; gel: 970 ppm F, 3,030 ppm Sn as SnF(2)). A mouth rinse (500 ppm F as AmF/NaF, 800 ppm Sn as SnCl(2)) was the positive control. Tissue loss was quantified profilometrically. In experiment 1, most NaF toothpastes and 1 F-free formulation reduced tissue loss significantly (between 19 and 42%); the Sn-containing formulations were the most effective (toothpaste and gel 55 and 78% reduction, respectively). In experiment 2, only 4 NaF toothpastes revealed significant effects compared to the F-free control (reduction between 29 and 37%); the F-free special preparations and the Sn toothpaste had no significant effect. The Sn gel (reduction 75%) revealed the best result. Conventional NaF toothpastes reduced the erosive tissue loss, but had limited efficacy regarding the prevention of brushing abrasion. The special formulations were not superior, or were even less effective. 相似文献
19.
ObjectiveTo evaluate the effects of three different radiotherapy doses (20, 40, and 70 Gy) on the microhardness, superficial morphology, and mineral content (based on Ca and P values) of three different depths of human enamel (cervical, middle, and occlusal).DesignThirty-four third molars were cut, separated, and prepared. Microhardness samples (n = 30) were embedded in acrylic resin and then polished, and depths were delimited. Microhardness tests were performed on cervical, middle, and occlusal enamel pre- and post-radiotherapy with a load of 50 g for 30 s. For the scanning electron microscopy (SEM) analysis (n = 4) and energy dispersive X-ray spectroscopy (EDS) (n = 12), samples were fixed in a 3% glutaraldehyde solution, washed in 0.1 M cacodylate solution, and dehydrated in crescent concentrations of ethanol. Microhardness data were tested for significant differences using a two-way analysis of variance (ANOVA) and Tukey’s test (p < 0.05), while SEM and EDS were evaluated qualitatively.ResultsThe results showed a decrease in microhardness values only in the cervical enamel, regardless of the radiation dose used; no morphological or mineral change was observed.ConclusionRadiotherapy can affect the microhardness values of only cervical enamel without compromising the morphological or mineral (Ca and P) content at any depth. 相似文献
20.
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。 相似文献