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...     

Fluoride concentration in supragingival dental plaque after a single intake or habitual consumption of fluoridated milk

The aim of this study was to evaluate the fluoride concentration in supragingival dental plaque after single and repeated intakes of fluoridated milk. The study group consisted of 22 schoolchildren, young adults and adults of both sexes, 8-41 years of age. After a 2-week fluoride depletion period and 3 days of plaque accumulation, 200 ml of fluoridated milk (1g F) was ingested along with a standardized lunch meal. Plaque samples were collected immediately before the intake and after 30, 120 and 240 min. From the adult participants (n = 9), additional samples were colleted after 12 and 18 h. After a fluoride-free washout period of at least 2 weeks, the whole experimental procedure was repeated after 4 consecutive daily intakes of fluoridated milk. The fluoride concentration was determined after micro-diffusion with a fluoride selective electrode. The results showed a statistically significant 3-fold increase of the plaque fluoride levels up to 4 h after the intake. At 12 and 18 h after the intake, the recorded levels went gradually back to baseline. There was no significant difference between the fluoride concentrations in the supragingival plaque after the single intake compared with the repeated intakes. In conclusion, the findings support the suggestion that milk is a suitable vehicle for local fluoride administration into the oral cavity, also when consumed together with a meal.     

Caries incidence after topical application of varnishes containing different concentrations of sodium fluoride: 3-year results

Abstract— Previous studies have shown that topical application of the fluoride varnish Duraphat reduces caries incidence. The aim of the present study was to compare the caries inhibiting effect of a new fluoride varnish (Carex) containing 1.8% fluoride (F) with that of Duraphat (2.26%F). Informed consent was obtained from the guardians of 495 children 10-12 yr old in Voss Dental Health District (low F area). The children were randomly allocated to two groups. One group of subjects received 6-monthly application of Duraphat (n=185), the other Carex (n=165). Ethical considerations precluded the use of a placebo varnish. All participants received dental examinations including one pair of posterior bitewing radiographs and necessary dental care annually. One trained examiner interpreted bitewing radiographs blindly. Total 3-yr net DFS increment for 24 posterior approximal surfaces was 2.63 (SD = 3.81) in the Duraphat group and 2.12 (SD = 3.50) in the Carex group. DMFS increments based on 40 posterior occlusal and approximal surfaces were 5.21 (SD = 5.79) and 4.04 (SD = 4.92), respectively. Thus the results indicate a comparable efficacy for Carex and Duraphat at the caries activity level exhibited by these study participants.     

Fluoride concentration in whole saliva and separate gland secretions after topical treatment with three different fluoride varnishes

Fluoride concentration in whole saliva and in separate gland secretions was determined after a single application of each of 3 different fluoride varnishes with contrasting levels of fluoride in a randomized crossover design. The study group comprised 8 healthy schoolchildren aged 10-12 years treated with A: Bifluorid 12 (6% F); B: Duraphat (2.26% F); and C: Fluor Protector (0.1% F). Unstimulated and stimulated whole saliva, as well as stimulated parotid and submandibular-sublingual saliva, were collected at baseline and 1, 6, 12, and 24h after the varnish treatments. The fluoride concentrations were determined with an ion-selective electrode. Time- and dose-dependent concentration curves were obtained in all the collected secretions, A > B > C. In whole saliva, the fluoride levels were significantly elevated (P<0.01) 1 h after the A and B varnish applications compared with baseline, while the increase was insignificant for varnish C. Similar patterns were unveiled in the parotid and submandibular-sublingual secretions, although the increase in fluoride concentration was modest. The elevated levels did not exceed 6 h for any of the varnish tested. The results of this study suggest a correlation between the concentration of fluoride of the varnish and fluoride levels obtained in saliva after application.     

The effect of a preventive program, including the application of low-concentration fluoride varnish, on caries control in high-risk children

The aim of this 2-year prospective randomized clinical study was to evaluate the efficacy of a prevention program for schoolchildren with high caries risk. A sample of 419 subjects was divided into a test (T, n=259) and control group (C, n=160). Four times a year, the test group received professional tooth-cleaning and application of a 0.1% fluoride varnish as well as motivation and instruction in oral hygiene. The control group received only oral hygiene instruction and took part in supervised tooth-brushing once a year. At baseline and after 2 years, the D₃,₄MFS and the incipient lesions (D_1,2) were recorded. After 2 years, 318 subjects (T=187, C=131) were included in the data analysis. The baseline D_1,2 was 6.18 (T) and 5.50 (C), the D₃,₄MFS 2.13 (T) and 2.08 (C), respectively. No statistically significant difference was found for the baseline values. At the final examination, the D_1,2 increment was 3.96 in the test and 6.53 in the control group, showing a statistically significant difference (P<0.001). No such difference was found for the D₃,₄MFS increment (T: 2.22; C: 2.61). The results indicate that it might not be possible to prevent cavities in high caries risk children by means of the described program. Received: 24 August 2000 / Accepted: 18 September 2000     

Microhardness changes in surface enamel after application of bioadhesive fluoride tablets in situ

The effect of fluoride released by bioadhesive tablets was evaluated in an in situ model in human volunteers. Eight volunteers carried four to six polished human enamel samples in a lower lingual device for a period of 5 days without fluoride supplements (control) and 5 days using one bioadhesive tablet (0.5 mg F) per day, placed in the lower buccal sulcus. Changes in mineral content were measured in terms of surface microhardness indentation length (load 0.98 N, Knoop diamond indenter). Some enamel samples were analyzed for their fluoride content by means of a surface etch biopsy. The indentation length increased significantly in both experiments, but demineralization was less pronounced with fluoride (indentation length increased from 44±7 to 48±13 μm) than in the control (44±7 to 58±13 μm). The fluoride concentration and the amount of calcium in the acid etch biopsy specimens of the enamel samples did not differ significantly between the two groups. Bioadhesive, fluoride-releasing tablets have therefore demonstrated the potential to reduce demineralization by elevating salivary and plaque fluoride concentration for a period of several hours. This self-administered device can be a supplementary means for prevention of caries. Received: 2 February 2000 / Accepted: 2 May 2000     

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。     

A comparison of different indices used in the clinical assessment of plaque and gingival bleeding

Indices are used in order to describe clinical variables used in the assessment of periodontal health and diseases. Indices may be divided into those that quantify variables, and those that simply annotate the presence or absence of variables. In this study, quantitative and binary (presence/absence) indices were compared in the evaluation of dental plaque and gingival bleeding. As the data were not directly comparable, they were transformed into percentage changes occurring between consecutive assessments. It was found that the differences between the two types of indices used to assess dental plaque and bleeding on gentle probing were marginal. Thus it was concluded that, the use of quantification indices may have little or no clinical benefit, and did not warrant the extra expenditure of time and effort required for their administration. However, in more detailed clinical and epidemiological trials designed to evaluate the distribution of clinical variables on different regions of tooth surfaces, the quantification indices are necessary. Therefore binary/dichotomous indices may be used effectively, especially in the daily clinical work without recourse to the more detailed and complex quantitative indices. Received: 26 February 1999 / Accepted: 6 May 1999     

缓释氟粘贴片对唾液氟浓度的影响

目的 为了实现最佳防龋效果,我们研制了一种缓释氟粘贴片,它含0.25mgF^-或0.5mgF^-,可以在人工唾液中缓慢释放氟化物约4小时,本实验研究它在口腔中的释放情况。方法 饮用水氟为0.2ppm的健康受试者12人,实验中禁食,留样前半小时禁水,把一种剂量的氟片贴在右上中切牙唇面,放药前和放药后的不同时间（0.25,0.5,1,2,3,4,5和6小时）分别留非刺激性唾液,唾液离心后测定上清液氟浓度。观察药片全部溶蚀的时间和局部粘膜的变化。5天后进行阵 剂量氟片的实验。结果 该氟片在2.5小时以内溶蚀,但唾液有效氟浓度时间持续5－6小时以上,唾液氟高峰出现在0.5小时,未见粘膜刺激性。结论 该氟片使用方便,局部未见刺激性,可能是临床提高唾液氟浓度、预防龋齿的有效方法,但还需进一步研究。     

成膜基质对氟化物涂膜提高釉质抗脱矿性能的影响

目的:评价成膜基质材料对氟化物涂膜提高釉质体外抗脱矿性能的影响。方法:在制备的5组牛牙釉质试样表面分别涂布以5种成膜基质(渗透型丙烯酸树脂、珂巴树脂、聚合松香、聚乙烯醇缩丁醛、甲基丙烯酸共聚树脂)配制的5种氟涂膜材料,另有一组不做处理,为对照组。在保湿12 h后,除去涂膜,然后对所有试样进行脱矿-再矿化循环处理7 d,之后纵向剖切试样,测定纵剖面显微硬度(HK),并用扫描电镜观察釉质处理面。结果:在釉质表面下90μm深度范围内的相同深度,所有涂膜组釉质的显微硬度均明显高于对照组(P<0.05);在釉质表面下50μm深度范围内的相同深度,渗透型丙烯酸树脂组的釉质硬度大于其它4组(P<0.05);各组釉质表面在扫描电镜下呈现不同特点的脱矿形式。结论:成膜基质材料对氟化物涂膜提高釉质体外抗脱矿性能有明显影响,含渗透型丙烯酸树脂的氟涂膜对抗釉质脱矿效果更佳。     

应用新一代高通量测序技术探讨含氟涂料对患龋乳前牙菌斑微生物的影响

目的 应用新一代高通量测序技术,了解含氟涂料处理患龋乳前牙前后菌斑微生物的变化。方法 选取20名乳前牙患龋的学龄前儿童,菌斑生物膜样本采自含氟涂料处理前和处理后3天、7天和30天的乳前牙患龋牙面;抽提全基因组DNA后,用16S rRNA基因V4-V5高变区为引物扩增后,运用MiSeq测序平台测序并分析。结果 4个时间点菌斑生物膜微生物多样性Shannon指数的比较表明,涂氟后3天、后7天比涂氟前的Shannon指数更低（P=0.011;P=0.016）,提示菌斑生物膜的微生物多样性降低;涂氟后30天和涂氟前的Shannon指数持平（P>0.05）,提示涂氟后菌斑生物膜的微生物多样性恢复至涂氟前的状态;PCA分析也进一步表明和Shannon指数一致;4个时间点优势菌属的比较表明涂氟后3天、后7天、后30天和涂氟前优势菌属的种类和相对丰度均没有差异,说明含氟涂料对菌斑生物膜的多样性的抑制作用没有特异性。结论 含氟涂料对患龋乳前牙牙面菌斑微生物在一定时间内有明显的抑制作用,抑制作用无特异性,微生物多样性经过一段时间还能恢复至原有状态。     

Effect of pH on fluoride penetration into natural human plaque

Since recent studies have demonstrated that penetration profiles of fluoride into plaque falls from the saliva plaque interface towards the enamel, it was hypothesized that charged components may restrict the inward diffusion of fluoride i.e., protonated fluoride and may penetrate more effectively than fluoride ion. Therefore, in this study, we investigated the effects of pH on fluoride uptake and distribution in natural undisturbed human plaque formed in vivo by means of the Leeds in situ device. At pH 3 significantly less fluoride was present throughout the plaque layer compared with pH 7. Similar profiles were seen in the plaque produced over 1 week and 3 weeks. These results may be due to binding to components of the plaque matrix via hydrogen bonding. Protonation of bacterial cell surfaces may also lead to binding of the ionized portion of fluoride. In conclusion, low pH affected the short-term fluoride uptake from a 1,000 ppm fluoride solution.     

含氟牙膏刷牙后菌斑和唾液中氟离子浓度的变化

目的 :测定正常人使用含氟牙膏刷牙后 ,菌斑及唾液中氟离子浓度 ,并探讨其对龋病预防的意义。方法 :选择 16名自愿者 ,用离子选择性氟电极测定含氟牙膏刷牙后 2小时菌斑及唾液中氟离子浓度 ,并与基线水平相比较。结果 :含氟牙膏刷牙后 2小时 ,牙菌斑及唾液中氟浓度分别为 5 1.5 5± 14.15 μg/g菌斑湿重和 13.36± 3.81μmol/L ,较基线水平有显著性提高 (P <0 .0 1)。结论 :用含氟牙膏刷牙后使菌斑和唾液达到并维持的氟浓度 ,尤其是菌斑中氟浓度 ,可有效地抑制菌斑细菌的糖酵解过程 ,从而起到预防龋病发生的作用     

窝沟封闭加局部用氟对龋高危儿童防龋效果观察

目的探讨窝沟封闭术联合局部应用含氟涂料对龋高危儿童龋齿的预防效果。方法选择6~8岁,乳牙龋牙数不低于4颗且至少有1颗深龋或需牙髓治疗的龋高危儿童51例为研究对象,双侧同颌第一恒磨牙作为受试牙,共146颗。采用自身半口对照方法,随机选择一侧受试牙应用窝沟封闭术,另一侧应用窝沟封闭术联合含氟涂料涂布,分别设为对照组和试验组。定期复查封闭剂保留情况和患龋情况。结果 12、18个月时,试验组龋齿发生率显著低于对照组（P〈0.05）,龋坏主要发生在封闭剂脱落的窝沟内。结论相比单一的龋病预防模式,联合应用窝沟封闭和含氟涂料,能更有效地降低龋高危儿童龋病发生率,减少龋病对儿童牙齿的破坏,值得临床推广应用。     

An in vitro study of fluoride release from a resin-modified glass ionomer cement after exposure to toothpaste slurries of different pH

. The aim of the study was to evaluate the fluoride release from an aged resin-modified glass ionomer (Vitremer) after exposure to five toothpaste slurries with different pH values. Cylindrical specimens of the material were leached in de-ionized water for 3 months and then exposed for 30 min daily for 10 days to three dentifrice slurries (20 specimens/group) containing 0.05% fluoride with pH values of 2.6, 5.7 and 8.3 and two non-fluoridated slurries with pH values of 2.5 and 5.7. A neutral NaF solution (0.05% F) was used as a control. During the 30 min exposure time, the fluoride concentration was gradually decreased in order to imitate the clinical situation. Thereafter, specimens were immersed individually in de-ionized water and the fluoride release determined. After the first day of exposure, all groups except one without fluoride (pH 5.7) showed significantly (P<0.05) increased fluoride release. After exposure to the fluoridated toothpaste slurry with pH 5.7, significantly (P<0.05) more fluoride was released compared to the toothpaste slurry with pH 8.3. Low pH (2.5 or 2.6) of the slurry resulted in a significantly (P<0.05) higher fluoride release, regardless of whether it was fluoridated or not. The total amount of fluoride released after exposure to the more acidic fluoride toothpaste slurry was greater than that released from the more acidic non-fluoride toothpaste and the less acidic fluoride toothpaste. Our data indicate that the fluoride release from the resin-modified glass ionomer studied may be in-creased after treament with an acidified NaF-toothpaste. Received: 24 January 2000 / Accepted: 20 July 2000     

Caries incidence after topical application of varnishes containing different concentrations of sodium fluoride: 3-year results.

Previous studies have shown that topical application of the fluoride varnish Duraphat reduces caries incidence. The aim of the present study was to compare the caries inhibiting effect of a new fluoride varnish (Carex) containing 1.8% fluoride (F) with that of Duraphat (2.26% F). Informed consent was obtained from the guardians of 495 children 10-12 yr old in Voss Dental Health District (low F area). The children were randomly allocated to two groups. One group of subjects received 6-monthly application of Duraphat (n = 185), the other Carex (n = 165). Ethical considerations precluded the use of a placebo varnish. All participants received dental examinations including one pair of posterior bitewing radiographs and necessary dental care annually. One trained examiner interpreted bitewing radiographs blindly. Total 3-yr net DFS increment for 24 posterior approximal surfaces was 2.63 (SD = 3.81) in the Duraphat group and 2.12 (SD = 3.50) in the Carex group. DMFS increments based on 40 posterior occlusal and approximal surfaces were 5.21 (SD = 5.79) and 4.04 (SD = 4.92), respectively. Thus the results indicate a comparable efficacy for Carex and Duraphat at the caries activity level exhibited by these study participants.     

Relationship between bone mineral loss and urinary fluoride concentration in postmenopausal Japanese women

 The purpose of this study was to evaluate the relationship between bone mineral loss and urinary fluoride (F) concentration in postmenopausal Japanese women. Lumbar spinal bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) at baseline and 1 year later in 94 premenopausal and 100 postmenopausal women. None of the subjects had any bone-related disorders. There were significant correlations between urinary F concentration and time since menopause (r = 0.397; P < 0.05), and between annual BMD loss and urinary F concentration at baseline (r = −0.492; P < 0.01) in the postmenopausal women. However, there was no significant correlation between urinary F concentration and BMD either at baseline or 1 year later. Urinary F concentration tended to be higher in postmenopausal women with low blood estradiol (E₂) concentration than in those with normal blood E₂ concentration. Our results suggested that urinary F concentration may be a useful marker to assess bone resorption in postmenopausal women. Received: September 19, 2001 / Accepted: May 8, 2002     

In vitro enamel erosion and abrasion-inhibiting effect of different fluoride varnishes

ObjectiveTo investigate the erosion and abrasion inhibiting effect of CPP-ACP/NaF and xylitol/NaF varnishes.MethodsBovine enamel samples (n = 40) were exposed to the following treatments (n = 10): NaF varnish (Duraphat^®, positive control); CPP-ACP/NaF varnish (MI varnishTM); xylitol/NaF (Profluorid^®) or distilled and deionized water (MilliQ^®, negative control). The samples were submitted for 3 days to 4 cycles/day of erosion (5 min in Sprite Zero) and 2 cycles of abrasion/day after the first and last erosive challenge, with a toothbrush machine and slurries of a placebo toothpaste for 15 s (50 strokes/s). Among the cycles and after the last daily cycle, the specimens remained in artificial saliva. The change in the enamel surface was evaluated by using 3D non-contact optical profilometry with surface roughness (Ra and Sa values) and tooth structure loss (TSL) measurements. Scanning electron microscopy (SEM) assessed the enamel topographic characteristics. Differences in the Ra, Sa and TSL among treatments were tested using one-way ANOVA followed by the Tukey test.ResultsAll varnishes promoted better results for Ra and Sa values than the negative control (p = 0.0001), without difference among them (p > 0.05). However, CPP-ACP/NaF varnish stimulated fewer TSL (7.09 ± 0.70 μm) compared to NaF varnish (10.33 ± 1.36 μm, p = 0.002), xylitol/NaF varnish (9.96 ± 0.41 μm, p = 0.007) and the negative control (18.38 ± 3.32 μm, p = 0.0001).ConclusionA single-application of fluoride topical varnishes was effective in reducing enamel wear. The CPP-ACP/NaF varnish had the best effect against enamel loss from an erosion-abrasion challenge.