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1.
目的:采用定量光导荧光系统观察含氟涂料对牛牙釉质的抗酸性效果。方法:20个新鲜拔除的牛前牙,于每个标本唇面建立4个2mm×2mm开窗,随机分为4组,分别用含氟涂料、含氟牙膏、1%氟化钠溶液、去离子水处理,然后浸泡在脱矿液中,分别于处理的第1,2,4,8d,采用QLF法检测各组标本的荧光损失量△F(%)和病变面积△P(mm2),计算△Q(%,mm2),并再次处理。结果:用含氟涂料处理的牛牙釉质龋标本,再矿化面积最多、△Q降低最大,且与其他处理组有显著差异(P〈0.05)。结论:同其它方法相比,含氟涂料有利于增进离体牛牙釉质的抗酸性。  相似文献   

2.
The aim of this examiner-blind, clinical monitoring was to observe long-existing white spot lesions over a period of 6 months and to evaluate the effectiveness of fluoridated toothpastes on these lesions. Thirty-nine subjects with at least one lesion participated in the study. They were randomly divided into two groups (n=20 and n=19) and instructed to brush their teeth either with toothpaste containing sodium fluoride (1500 ppm) (group 1) or with toothpaste containing amine fluoride (1250 ppm) (group 2). Lesions were measured with quantitative light-induced fluorescence (QLF) and alterations were quantified by DeltaQ as fluorescence loss integrated over the lesion area (% x mm(2)). All QLF images were taken by one examiner at baseline (DeltaQ1) and follow-up visits after 2, 4, 6, 8, 10, and 12 weeks, and after 4, 5, and 6 months (DeltaQ10). The results showed a slight but not significant progression of DeltaQ (% x mm(2)) in group 1 ((p>0.05; t-test), DeltaQ1 -20.31 (+/-41.06); DeltaQ10 -26.2 (+/-47.69)) and in group 2 ((p>0.05), DeltaQ1 -22.28 (+/-43.86); DeltaQ10 -26.39 (+/-46.4)). The results indicated no significant differences regarding the influence of the fluoridated toothpastes (p>0.05). It can be concluded that within 6?months the long-existing white spot lesions are stable concerning fluorescence loss over the lesion area. Moreover, fluoride does not seem to have any effect on long-existing white spot lesions.  相似文献   

3.
The purpose of the study was to determine if longitudinal measurements of enamel autofluorescence (quantitative light-induced fluorescence, QLF) could detect differences in remineralization of early enamel caries on buccal surfaces of anterior teeth following supervised daily brushing with either sodium fluoride (NaF; 1,450 ppm F), sodium monofluorophosphate (MFP; 1,450 ppm F) dentifrices or a herbal, non-fluoride placebo dentifrice. The study was a pragmatic cluster-randomized controlled trial with schools as the unit of randomization. Twenty-one schools in Chengdu, China, comprised the clusters; 296 children with at least 1 visible white-spot lesion were examined using QLF at baseline and after 3 and 6 months. Each of the 21 clusters was randomly assigned 1 of the 3 dentifrices, and the children brushed under supervision once per day for 2 min. The primary outcome measure was deltaQ (product of fluorescence loss and area) at a 5% threshold after 6 months of product use. A multi-level model was fitted to the data at the site level, taking into account the hierarchical structure with baseline deltaQ, age and sex as covariates. After 3 months there was a significant difference between the MFP group and placebo (p = 0.02) and after 6 months between the NaF group (p = 0.002), MFP group (p < 0.001) and the placebo. QLF methodology could detect, within 3- and 6-month periods of supervised brushing, a difference in remineralization between fluoride-containing and non-fluoride-containing dentifrices. Typically lesions in all 3 treatment groups demonstrated improvement. Groups receiving fluoride experienced a more rapid and more substantial remineralization than those in the placebo group.  相似文献   

4.
Caries inhibiting and remineralizing effect of xylitol in vitro.   总被引:1,自引:0,他引:1  
This study aimed to determine the effect of xylitol on the development and remineralization of caries in vitro, and to compare this effect with that of fluoride alone and in combination. Two experiments were devised. In experiment 1, bovine incisors were each sectioned into 4 portions which were randomly assigned to 4 demineralizing agents: A) acidic buffer (x), B) x + 0.5 ppm fluoride, C) x + 20% xylitol, and D) x + 20% xylitol + 0.5 ppm fluoride. Caries-like lesions were produced in specimens. In experiment 2, carious lesions were produced in teeth. Five lesion-bearing slabs were cut from each tooth. While one was reserved as control (UN), others were randomly assigned to 4 remineralizing agents: 1) artificial saliva (y), 2) y + 0.05 ppm fluoride, (3) y + 20% xylitol, and 4) y + 20% xylitol + 0.05 ppm fluoride. Mineral loss (delta Z) and lesion depth (ld) were quantified after 4-week remineralization. In experiment 1, numerical values of delta Z and ld observed can be ranked as A > C > B > D. These differences were significant only in B and D when compared with A for delta Z, but not between any group for ld. In experiment 2, the numerical values of delta Z and ld for control UN (unremineralized) and remineralized groups (1-4) ranked as UN > 3 > 4 > 1 > 2. Compared with UN, this difference was significant in all groups with ld, but not in any group with delta Z. We concluded that tolerable levels of xylitol alone may not show a significant caries inhibiting and remineralizing effect, but may act as a caries inhibitor additively with fluoride.  相似文献   

5.
The present study investigated de- and remineralization in enamel lesions under plaque fluid (PF)-like conditions using quantitative light-induced fluorescence (QLF). Preformed lesions were exposed to partially saturated lactic acid solutions, varying in pH and fluoride concentration ([F]) based on a 5 × 3 factorial study design (0/0.1/0.5/1.5/4 ppm F; pH 4.9/5.2/5.5). Average fluorescence loss (ΔF) was monitored for 11 days. Subsequently, lesions were demineralized in a partially saturated acetic acid solution for two 24-hour periods. Data were analyzed using repeated measures analysis of covariance. Lesions exposed to PF at 4 ppm F and pH 5.5 showed not only the most remineralization (ΔΔF = 28.2 ± 14.0%) for all groups after 11 days, but also the most demineralization (ΔΔF = -19.3 ± 13.5%) after subsequent acetic acid exposure. Increased [F] resulted in more remineralization, regardless of pH. Higher pH values resulted in more remineralization. No remineralization was observed in lesions exposed to F-free solutions, regardless of pH. Remineralization was noticeable under the following conditions: pH 4.9 - [F] = 4 ppm, pH 5.2 - [F] ≥ 1.5 ppm, and pH 5.5 - [F] ≥ 0.5 ppm. Overall, [F] had a stronger effect on remineralization than pH. Subsequent demineralization showed that little protection was offered by PF-like solutions, and further demineralization compared with baseline was observed on lesions not remineralized initially. [F] had a stronger effect on net mineral change than pH. The present study has shown that QLF is a valuable tool in studying lesion de- and remineralization under PF-like conditions, where [F] was shown to be more important than pH.  相似文献   

6.
Remineralization of human enamel is an important issue in the prevention of caries. Fluoride has an important influence on the remineralization process. A great deal of research has been done into the role played by the method of application and by the concentration and type of fluoride. In the clinical study of this dissertation the process of remineralization of lesions in human enamel was longitudinally followed in vivo during a period of 3 months. Both the remineralization in the surface softened enamel lesion and the subsurface enamel lesion of human enamel were studied. In addition, attention was devoted especially to the influence of fluoride on this remineralization. The results indicated that the use of a 1,500 ppm fluoridated NaF toothpaste was more effective on the remineralization process than the use of a 50 pmm NaF mouthrinse. Important is the fluoride gradient in the enamel lesion, and in particular the fact that fluoride reaches the lesion front. This most likely accounts for the remineralization efficiency.  相似文献   

7.
In this study, the differences in lesion remineralization and fluoride uptake after brushing with a 300 ppm F or a 1000 ppm F dentifrice (as NaF) were investigated. Twenty volunteers with partial dentures in their lower jaws were divided into two groups. Bovine enamel slabs with artificial lesions were mounted in the dentures. After a test period of six weeks, the slabs were taken out and analyzed. There was no statistically significant difference between the two groups, in F-uptake and susceptibility of the enamel to demineralization, although the findings favored the 1000 ppm F toothpaste. The microradiograms in the 300 ppm F group showed lesions more pronounced than those in the 1000 ppm group. The present study cannot support the presumption that the fluoride content of regular NaF dentifrices can be lowered to 300 ppm F without undesirable effects on lesion arrest and remineralization.  相似文献   

8.

Objectives

To investigate the remineralizing effects of fluoride mouthrinses used at different times and frequency in addition to fluoride toothpaste.

Methods

A randomized crossover single blinded study comprised 4 experimental phases of 21 days each. Twelve orthodontic volunteers were fixed with an orthodontic bracket containing an artificial carious enamel slab, which was from the same tooth in all 4 phases, and were randomly assigned to the following groups: (1) brushing with F toothpaste 2× per day (F- brush), (2) F- brush + rinsing with 0.05% NaF (F- rinse) after lunch, (3) F- brush + F-rinse before bedtime, and (4) F- brush + F- rinse 2× per day. Mean mineral gain after each phase was determined from mineral density profiles obtained using Micro-CT.

Results

The mean mineral gain in all treatments with F- brush and F-rinse were significantly greater than those in F- brush (p < 0.05). Moreover F- rinse 2× per day increased lesion remineralization more than F- rinse once a day.

Conclusions

The twice-daily use of 0.05% NaF mouthrinse combined with twice-daily regular use of fluoride toothpaste resulted in the greatest remineralization of incipient caries. These data indicate that rinsing frequency is a factor affecting the effectiveness of fluoride mouthrinse.

Clinical significance

The rinsing frequency of NaF mouthrinse, when used with fluoride toothpaste, also affects the remineralization. This finding, if confirmed by a clinical study, would lead to a new recommendation for fluoride mouthrinse used in high caries risk patients who could benefit from using it twice a day.  相似文献   

9.
This in vitro study aimed at investigating whether full remineralization would occur in white spot lesions when the surface porosity was increased by acid-etching. The effect of fluoride was also investigated. Enamel blocks with in vitro produced white spot lesions were used. Group A was exposed to a remineralizing solution only. In group B, the lesions were etched with 35% phosphoric acid for 30 s, then treated as in group A. Group C was treated as group A + daily treatment with a fluoride toothpaste slurry (1,000 ppm) for 5 min. Group D was treated as group B + the daily fluoride treatment of group C. The remineralization was measured weekly with Quantitative Light-induced Fluorescence during the experimental period. After 10 weeks of remineralization, mineral profiles were assessed with transverse microradiography. The enamel fluorescence was partly regained. There were significant differences in the lesion depth, mineral content at the surface layer, and integrated mineral loss between the groups. Addition of fluoride accelerated the remineralization only in the beginning; in later stages the process leveled out and even reached a plateau in all the groups. It was concluded that full remineralization was not achieved by etching, by the addition of fluoride, nor by the combination of both treatments in this in vitro study.  相似文献   

10.
目的 选择体外实验证实具有较强的促进釉质早期龋再矿化作用的微量元素矿化液 ,评价其在体内的脱矿及再矿化效果。方法 制备含 2mm× 2mm正常和人工龋釉质块的可摘口内装置 ,将其置于受试者口内 ,采用激光共聚焦技术观察罗丹明B荧光染料渗透进入多孔釉质荧光量的多少 ,量化受试者在使用不同矿化液前后的再矿化效果 ,用ΔZa、ΔZb 及ΔZ(Zb 与ΔZa 的差值 )来表示 ,具体包括测釉质块荧光量的面积 (Areaofthefluorescentlesion ,A)、总的荧光量 (totalfluorescence ,TF)及病损的平均荧光量 (averagefluorescent,AF) 3个共聚焦参数。结果 受试者口内装置经含氟矿化液和微量元素矿化液处理后脱矿釉质块的共聚焦参数ΔZa 与处理前的ΔZb 相比差异有显著性 (P <0 0 5) ,尤以微量元素组明显。其激光共聚焦结果为 ,ΔZ :A =(- 50 4± 8 1 ) μm2 ,TF =- 2 7 8± 3 8,AF =- 91 5± 8 9,说明微量元素矿化液在体内仍能获得比单纯含氟矿化液更好的促进早期龋再矿化的效果。结论 微量元素矿化液有完善现有含氟矿化液防治早期龋的潜力 ,为临床的进一步应用奠定基础 ,为脱矿和再矿化研究提供了新方法  相似文献   

11.
PURPOSE: To evaluate fluoride uptake in enamel after use of products containing different fluoride components of distinct oral hygiene regimen in vivo. METHODS: 84 healthy subjects (24 females and 60 males aged 19-26 years, mean 22.2) recruited from the students attending the courses of the Medical Faculty of the University of Sassari, Italy, were randomly assigned to one of four treatments groups: A: treated with a dentifrice containing sodium monofluorophosphate (1250 ppm F-); B: treated with dentifrice with 1250 ppm F- from AmF; C: treated with an AmF toothpaste (1250 ppm F-) and a mouth rinse with 250 ppm F- from AmF; or D: treated with a NaMFP toothpaste (1250 ppm F-) plus 1250 ppm NaMFP varnish. Acid-etched enamel microbiopsies on the vestibular surface of the first maxillary premolar were collected at baseline (to), after 20 days of test product use (t1) and after 24 hours without treatment (t2). Fluoride concentration was measured using an ion-specific electrode. All measurements were made in triplicate and analyzed statistically using two-way factorial ANOVA for independent samples standard weighted-means analysis. RESULTS: The fluoride uptake in the enamel shows a considerable variation between the groups. Significant differences were found both within all products in terms of fluoride concentration in enamel for (P < 0.0001 for two-way ANOVA, and later Tukey HSD test). After 20 days of treatment, the group using AmF toothpaste plus AmF mouthrinse had a higher fluoride uptake than the groups using either of the other products (P < 0.05). In conclusion, all products lead to an appreciable amount of fluoride uptake in enamel; AmF products led to higher concentrations. The concentration of fluoride accumulated during treatment phase remained high after 24 hours following the cessation of use.  相似文献   

12.
The remineralization potential of fluoride toothpastes was studied using an in situ enamel insert model. Matched blocks of artificially demineralized human enamel were attached to partial dentures of 16 adult volunteers who brushed their teeth with either a toothpaste containing 1,500 ppm F or one containing 2,500 ppm F for a period of 6 weeks in a balanced, randomized crossover experiment. Computerized image analysis of microradiographs was used to measure the mineral density distribution in the enamel before and after in situ treatment. Both toothpastes demonstrated remineralization of artificial carious lesions. Significantly more remineralization was observed in enamel samples treated with the toothpaste containing 2,500 ppm F compared to that containing 1500 ppm F. This result is consistent with the outcome of a recent caries clinical trial testing the same toothpastes and finding enhanced anticaries efficacy from the higher fluoride level.  相似文献   

13.
This in vitro study aimed at investigating whether full remineralization would occur in white spot lesions when the surface porosity was increased by acid-etching. The effect of fluoride was also investigated. Enamel blocks with in vitro produced white spot lesions were used. Group A was exposed to a remineralizing solution only. In group B, the lesions were etched with 35% phosphoric acid for 30 s, then treated as in group A. Group C was treated as group A + daily treatment with a fluoride toothpaste slurry (1000 ppm) for 5 min. Group D was treated as group B + the daily fluoride treatment of group C. The remineralization was measured weekly with Quantitative Light-induced Fluorescence during the experimental period. After 10 weeks of remineralization, mineral profiles were assessed with transverse microradiography. The enamel fluorescence was partly regained. There were significant differences in the lesion depth, mineral content at the surface layer, and integrated mineral loss between the groups. Addition of fluoride accelerated the remineralization only in the beginning; in later stages the process leveled out and even reached a plateau in all the groups. It was concluded that full remineralization was not achieved by etching, by the addition of fluoride, nor by the combination of both treatments in this in vitro study.  相似文献   

14.
目的比较几种不同成分牙膏促进脱矿釉质再矿化的作用。方法选择新鲜拔除的牛下颌切牙制备成釉质块,形成早期人工龋。随机分为5组,各组依次为精氨酸牙膏组、氟离子浓度为0.11%牙膏组、酪磷酸蛋白牙膏组、氟化钠组(阳性对照组)、去离子水组(阴性对照组)。分别进行pH循环后,试验样本依次用显微硬度仪、偏光显微镜、激光共聚焦镜对再矿化程度进行检测。运用SPSS17.0软件,对检测结果进行单因素方差分析及配对t检验分析。结果显微硬度检测结果显示:精氨酸牙膏组、氟化钠组及酪磷酸蛋白牙膏组比0.11%含氟牙膏组的显微硬度恢复的百分比高(P〈0.05)。偏振光显微镜检测结果显示:酪磷酸蛋白牙膏组脱矿深度恢复的百分比高于0.11%含氟牙膏组,而较精氨酸牙膏组、氟化钠组低。激光共聚焦显微镜检测结果显示:酪磷酸蛋白牙膏组与0.11%含氟牙膏组荧光渗透减少量较精氨酸牙膏组及氟化钠组少。结论在本实验条件下,精氨酸牙膏、酪磷酸蛋白牙膏都能一定程度的促进早期釉质龋的再矿化作用,其中以精氨酸牙膏作用最强。  相似文献   

15.
The effect of fluoride and xylitol on remineralization at the early stage of the enamel caries in primary tooth was studied. The samples were divided into four groups (control, 10% xylitol, 950 ppm NaF and 10% xylitol+950 ppm NaF) and analyzed by the using single thin section method and pHcycling model in vitro. The remineralizing ratio were control –8.9%, xylitol –0.4%, NaF 8.3% and xylitol + NaF 32.4%, respectively. Xylitol+NaF group particularly showed significantly smaller ΔZ value compared with 0 days (P<0.05). Therefore we assume that the effect of xylitol and fluoride are additive. We concluded that xylitol and fluoride treatment to the tooth enamel may be an effective caries-preventive measure in both primary and permanent tooth enamel.  相似文献   

16.
Abstract

Objective. To compare the effects on enamel demineralization and fluoride (F) retention of two different brushing–rinsing regimens. Material and methods. An in-situ caries model with orthodontic bands was used for 8–9 weeks. A total of 20 orthodontic patients participated. They were randomized into two groups: (1) a test group using 5000 ppm F (n = 10) with no post-brushing water rinsing; and (2) a control group using 1450 ppm F (n = 10) with three sessions of post-brushing water rinsing. Orthodontic stainless-steel bands were applied to the two upper first premolars, leaving 2–3 mm of space away from the exposed buccal surface in order to accumulate plaque and provoke initial caries development. The teeth were extracted after 8 and 9 weeks, then analysed using quantitative light-induced fluorescence (QLF). Additionally, oral F retention was compared for the two groups. Results. In comparison to the control group, the test regimen resulted in a non-significant smaller QLF lesion area and a significantly lower average QLF loss of fluorescence (P < 0.05). The highest F retention concentration under the band was found in the test group (P < 0.001). Conclusions. The combination of using a 5000 ppm F toothpaste and no post-brushing water rinsing had a greater anti-caries potential and resulted in elevated oral F retention compared to a 1450 ppm F toothpaste with three sessions of post-brushing water rinsing.  相似文献   

17.
This study aimed to determine the anti-erosive effects of xylitol, fluoride and a xylitol/fluoride combination used as an additive in an acidic drink or as mouthrinse after enamel was exposed to an acidic drink, in vitro. Human third molars were divided into 7 groups (A-G). Samples from groups A to D were immersed for 5 min in orange juice only (A), orange juice plus either 25% xylitol (B), F(-) 1 ppm (C) or a 25% xylitol/F(-) 1 ppm combination (D), respectively. Samples from groups E to G were immersed in orange juice for 5 min and then in either 40% xylitol (E), F(-) 227 ppm (F) or a 40% xylitol/F(-) 227 ppm combination (G), for 1 min respectively. This process was performed four times daily for 14 days. Mineral loss was determined from the lesion depth and surface hardness. Erosion depth progressively increased in all groups, except E, where erosion depth was significantly lower than group A. Surface microhardness progressively decreased in all groups, except E, where hardness was significantly higher than group A. This study demonstrated that addition of xylitol, fluoride or a xylitol/fluoride combination to an acidic drink or post-treatment with fluoride or a xylitol/fluoride combination could reduce, but not prevent, enamel erosion.  相似文献   

18.
Willmot DR 《Journal of orthodontics》2004,31(3):235-42; discussion 202
OBJECTIVE: To compare and measure the changes in size of post-orthodontic demineralized white lesion enamel lesions treated with a low fluoride (50 ppm) versus a non-fluoride mouthrinse/toothpaste regime. STUDY DESIGN: An experimental double-blind prospective randomized clinical controlled trial. SETTING: A university dental school orthodontic clinic (Sheffield, UK). PARTICIPANTS: Twenty-six patients identified as having post-orthodontic demineralized white lesions on removal of their fixed appliance. METHOD AND INTERVENTIONS: The participants were randomly and blindly assigned to either a low fluoride mouthrinse/toothpaste treatment regime or an inactive control. Computerized image analysis of calibrated photographic images taken under polarized light were used to measure the lesions. OUTCOME MEASURES: Lesion size and proportion (DWL%t) and percentage reduction (ADPR) at debond, and at 12 and 26 weeks later. RESULTS: Five participants dropped out of the study, 12 had the low fluoride regime and 9 did not. As a percentage of the total labial tooth area (DWL%t) the mean size of the lesions at debond was 8.1% (SD 3.7). After 12 weeks the mean size of lesion had reduced to 4.6% (SD 2.6), which was a significant reduction (p=0.03). After 26 weeks the mean size was 3.5% (SD 2.1), which was a very significant reduction (p<0.003). This confirmed statistically that post-orthodontic demineralized white lesions do reduce in size with time reflecting remineralization or other enamel surface changes. Intervention using a test low fluoride mouthrinse/toothpaste combination at 26 weeks showed an average difference percentage reduction (ADPR) of 54.3% (Upper 95% CI=62.08, Lower 95% CI=46.44%) compared with a non-active control combination, which showed an ADPR of 66.1% (Upper 95% CI=77.74, Lower 95% CI=54.51%). This failed to show any differences or therapeutic affect. CONCLUSIONS: Post-orthodontic demineralized white lesions reduced in size during the 6 months following treatment by approximately half the original size. There was no clinical advantage in using the low fluoride formulation of mouthrinse/toothpaste in this study.  相似文献   

19.
Remineralization experiments using bovine enamel were carried out with 2 ppm fluoride or no fluoride added to the remineralizing solutions. The group without fluoride showed (quantitative microradiography) significantly more remineralization in the first 50 microns of the lesion than the fluoride group. It is suggested that fluoride may inhibit remineralization.  相似文献   

20.

Background

One of the important factors of the demineralization and remineralization equilibrium of enamel is the pH of the surrounding solutions. Effort has been laid in the formulation of different fluoride compounds and the fluoride content in toothpastes but much less is known about the influence of the pH of the toothpastes on their effectiveness. It was therefore the aim of this study to investigate the influence of different pH levels on enamel remineralization in an in vitro experiment using polarization light microscopy and EDX quantitative element analysis.

Methods

A 5 × 5 mm window on the enamel surface of 40 caries free extracted human premolars was demineralized in a hydroxyethylcellulose solution at pH 4.8. The teeth were divided into 8 groups and the lower half of the window was covered with varnish serving as control. Each group was then immersed in toothpaste slurry containing amine fluoride (1400 ppm) at pH 4.1, 4.5, 5.1 and 6.9 or control toothpaste slurry without fluoride at pH 4.3, 4.7, 5.3 and 7.0. Serial sections were cut through the lesions and investigated with polarization light microscopy and quantitative EDX element analysis.

Results

The PLM results showed a decreased porous volume of the body of the lesion after incubation with fluoridated toothpaste at pH 4.53 and 5.16. No differences between the experimental window and the control window were found in the other groups. The quantitative element analysis showed no differences in the element content of any of the groups.

Conclusion

From the results it can be concluded that slightly acidified fluoridated dentifrices may have a certain positive effect on enamel remineralization.  相似文献   

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