美观充填材料氟离子释放的体外研究

目的：分析3种传统玻璃离子水门汀、4种玻璃离子树脂复合体和1种树 脂的释氟能力。方法：在体外测量每一个材料应用含氟凝胶前后各6周的氟离子释放量。结果：部分材料在测量初2d释氟水平高，之后迅速下降，在3－5周内维持于稳定水平。用含氟凝胶进行氟再吸收后。所有材料均有短暂而显著的释氟增加。结论：新型的复保体同玻璃离子水门汀一样，起氟储存库的作用。     

含氟复合树脂释氟量及其对吸水值和溶解值的影响

目的 研究含氟复合树脂释氟及释氟后对材料本身性能的影响。方法 用氟电极法测定释氟量、重量体积法测定吸水值和溶解值。结果 含氟复合树脂累积释氟曲线表现出快速释放期（约７ｄ）和缓慢释放期（７ｄ以后），复合体累积释氟曲线与时间呈直线关系，含氟材料吸水植（１３．０５～３１．６４μｇ／ｍｍ＾３）和溶解植（５．８８～２４．８０μｇ／ｍｍ＾３）大于对照材料。结论 复合树脂释氟可能会对材料的物理机械性能有一定影响     

六种牙齿充填修复材料的释氟与再充氟性能研究

目的 评价6种牙齿充填修复材料的释氟和再充氟性能,以期为临床选择和应用提供参考.方法 选择材料A(FujiⅦ玻璃离子水门汀)、材料B(FujiⅡLC光固化玻璃离子水门汀)、材料C(Beautifil离子体复合树脂)、材料D(Compoglass F复合体)、材料E(Charisma普通复合树脂)及材料F(实验Ⅰ型释氟性复合树脂)作为实验材料,制备直径10 mm、厚1 mm的圆片,每组10个试样.每个试样浸于5 ml去离子水中,用氟离子选择电极测定浸出液氟离子量,浸泡1～7d每天测定,8～28d3d测定1次,计算每日释氟量.于浸泡28 d后用氟化泡沫对试样充氟4min,继续测定试样每日释氟量,连续测定7d;再充氟并测定氟释放7d,重复3次.结果 浸泡1d后所有材料均表现最大的释氟量,材料A释氟量最大[(99.68±15.21) μg·cm-2·d-1],其次为材料B[(37.12±1.67) μg·cm-2·d-1],再次为材料F和D[分别为(22.93±1.53)和(15.28±0.70) μg·cm-2·d-1],材料C和E释氟量较小[分别为(2.40±0.52)和(0.11±0.02) μg·cm-2· d-1],各组间差异有统计学意义(P＜0.05).浸泡2d后释氟量显著下降,随后(7～ 28 d)释氟量下降缓慢;浸泡1～28 d内,材料A和B的释氟量始终大于其他材料(P＜0.01),其次是材料D和F,显著大于材料C和E(P＜0.01).所有材料充氟1d后的释氟量均较充氟前显著增加,形成释氟高峰,充氟2d后的释氟量又显著下降.充氟1d后材料A的释氟量超过40 μg· cm-2·d-1,大于其他材料(P＜0.01);其次是材料B,释氟量超过25 μg· cm-2·d-1,大于除A外的其他材料(P＜0.01);材料C、D、F释氟量相近,在15～ 20μg·cm-2·d-1之间;材料E释氟量较小,＜1.5 μg· cm-2·d-1.结论 玻璃离子水门汀类材料的释放及再充氟能力最强,其次是复合体和释氟性复合树脂,离子体复合树脂释氟能力小,但其再充氟能力与复合体和释氟性复合树脂相当,普通复合树脂的释氟及再充氟能力均较小.     

强化氟水门汀物理性能及释放氟研究

目的：探讨市售磷酸锌水门汀、聚羧酸锌水门汀、玻璃离子水门汀粉末中添加复合氟化物制剂（Co-F）对其物理性能及氟释放的影响。方法：在上述各水门汀粉末中按质量分数添加复合氟化物0％～20％，调和水门汀测定其固化时间、抗压强度、氟离子释放量。结果：添加适量复合氟化物对水门汀的抗压强度没有影响，添加复合氟化物的玻璃离子水门汀释放氟量增加，添加复合氟化物的聚羧酸锌水门汀、磷酸锌水门汀也能够释放氟离子。添加复合氟化物对聚羧酸锌水门汀及玻璃离子水门汀固化时间有明显影响。结论：强化氟水门汀通过释放氟，使充填材料附近牙齿发挥防治继发龋作用，基于此观点强化氟水门汀是牙科应用有希望的材料。     

含氟复合树脂释氟对材料挠曲强度的影响

目的：研究含氟复合树脂释氟对材料本身机械性能的影响。方法：选择不同氟含量的含氟树脂,以氟电极法连续30d测定含氟复合树脂体外释氟量。万能试验机测定含氟复合树脂释氟30d前后的挠曲强度。结果：含氟树脂氟含量越高（重量比分别为0％、0．3％、0．6％和1．2％）,初期释氟量越大（分别为0、21．98、43．98和99．91μg.cm^-2),相应挠曲强度越低（分别为101．70、94．29、82．03和79．84MPa）。随着含氟复合树脂释氟量的增加,材料的挠曲强度相应降低。结论：含氟树脂释氟对其机械性能有一定影响。     

一种复合体和四种树脂化玻璃离子水门汀的氟离子释放测定

目的 比较１种复合体和４种树脂化玻璃离子水门汀在水中释放氟离子的能力。方法 用氟离子选择电极，分别在第１、７、３０ｄ直径２５３ｄ，５种材料固化后标本浸泡训的氟离子浓度。结果 除复合体以外的所有材料，均显示了高的初期氟离子释入并急剧下降，然后缓慢下降。结论 复合体释放的氟离子比树脂化玻璃离子水门汀少。对于龋病高发的患者，选择高氟离子释放的树脂化玻璃离子水门汀材料较好。     

用于正畸托槽的氟化钠微胶囊释氟性能研究

目的比较改良型含氟正畸托槽中氟化钠微胶囊的长期氟释放情况。方法将氟化钠微胶囊及普通氟化钠分别按15％比例与树脂改良型玻璃离子水门汀（GC）混合,填充在改良型正畸托槽内,测定在50d内氟的释放量。结果氟化钠微胶囊组氟释放速度缓慢持续,曲线较平缓,氟化钠组在2d后释氟浓度大幅度下降,30d后低于氟化钠微胶囊组,差异有统计学意义（P〈0．05）。结论氟化钠微胶囊较普通氟化钠更适合用作缓释型含氟改良托槽。     

2种含氟窝沟封闭剂氟释放的体外研究

目的:观察和比较2种含氟窝沟封闭剂在人工唾液中的释氟情况.方法:将2种含氟窝沟封闭剂各制备5个6 mm×1.5 mm的盘状标本,浸入12 mL人工唾液中,恒温37℃.采用氟离子选择性电极法,分别于第1、2、3、7、14、21、28、35天测定2种窝沟封闭剂氟离子的释放量.结果:2种含氟窝沟封闭剂均在第1天的氟释放量最高,然后1周内急剧降低,在14～35 d内维持于稳定水平.在各时间点,玻璃离子封闭剂氟释放量均高于含氟树脂封闭剂,差异有统计学意义(P＜0.01).结论:新型含氟树脂窝沟封闭剂与玻璃离子封闭剂均能够作为氟库在一定时间内持续缓慢地向周围液体环境释放氟离子,对于窝沟封闭剂的防龋性能可能具有潜在的增强作用.     

含氟牙釉质粘接剂释氟的实验研究

目的：研究国产含氟牙釉质粘接剂的释氟性能。方法：制备含氟牙釉质粘接剂I型和Ⅱ型的测试标本，以ORION720型离子选择性氟电极、参比电极测试氟离子浓度。结果：I型及Ⅱ型含氟牙釉质粘接剂均有氟离子释放，且在第一个24h后氟离子浓度下降显著，可维持21d左右；Ⅱ型含氟牙釉质粘接剂初始状态释放氟离子水平较高。结论：I型及Ⅱ型含氟牙釉质粘接剂均有释氟性能,而以Ⅱ型含氟牙质粘接剂较佳。     

四种玻璃离子充填材料释氟性与溶解性的研究

目的 比较4种玻璃离子充填材料短期内氟离子释放能力和溶解性,为临床选择充填材料提供依据.方法 实验选取1种传统型玻璃离子水门汀(SC),2种高强度玻璃离子水门汀FujiⅨ(F9)和Ketac Moler(KM),1种树脂改良型玻璃离子水门汀FujiIILC (F2LC),和1种复合树脂Z100( CR,3M)共5种材...     

Effect of brushing on fluoride release from 3 bracket adhesives.

The purpose of this in vitro study was to compare fluoride ion release from 3 orthodontic bracket adhesives with and without brushing the bracketed teeth with a fluoridated dentifrice. The bracket adhesives included a light-cured composite resin (Transbond; 3M Unitek, Monrovia, Calif), a fluoride-releasing composite resin (Advance; L D Caulk Division, Dentsply International, Milford, Del), and a resin-modified glass ionomer (Fuji Ortho LC; GC America, Alsip, Ill). The teeth in the control group were not bonded with brackets. Sixty extracted human teeth were randomly assigned to 6 groups of 10 each: (1) Transbond, brushed; (2) Advance, brushed; (3) Advance, not brushed; (4) Fuji, brushed; (5) Fuji, not brushed; and (6) control, brushed. After bonding, each tooth was placed in a sealed plastic test tube containing 4 ml of deionized water. The toothpaste used in brushing contained 0.15% weight per volume sodium fluoride, 1500 parts per million parts fluoride (Winter-fresh gel; Colgate-Palmolive Co., New York, NY). Brushing began 24 hours after the teeth were bonded and placed in deionized water. After brushing, the teeth were thoroughly rinsed with deionized water and returned to a sealed test tube. Fluoride measurements were taken before brushing began, at intervals of 72 hours for 22 days, and 90 and 93 days after bonding. Findings included: (1) brushing significantly increased the release of fluoride ions from the teeth in the composite resin and control groups, (2) the enamel crowns of the unbonded control teeth absorbed and re-released a substantial amount of fluoride ions obtained from the toothpaste, (3) the brushed group of teeth bonded with the fluoride-releasing composite resin released significantly more fluoride on the last 4 days that measurements were taken after brushing than the nonbrushed group bonded with the same adhesive, (4) the brushed group of teeth bonded with the resin-modified glass ionomer released significantly more fluoride on the last 4 days that measurements were taken after brushing than the nonbrushed group bonded with the same adhesive, and (5) all groups released small amounts of fluoride ions 90 and 93 days after bonding (68.5 and 71.5 days after brushing ended); the resin-modified glass ionomer groups released significantly more fluoride than the other groups. Brushing with fluoridated toothpaste produced significantly greater fluoride release from teeth bonded with all 3 adhesives, and from the unbonded control teeth.     

Enamel fluoride uptake of a novel water-based fluoride varnish

Aim of the in situ-study was to evaluate fluoride retention in sound and demineralised enamel after application of a novel water-based fluoride (0.12% F) varnish Mirafluorid (Hager and Werken, Germany) compared to the resin-based varnish (2.26% F) Duraphat (Colgate, USA). Each five enamel specimens were prepared from 60 bovine incisors. In 150 of these specimens, incipient lesions were produced with acidic hydroxyethylcellulose (pH 4.8; 72 h), 150 specimens were not demineralised. The samples were equally (n=100) allotted to three groups (A: Mirafluord, B: Duraphat, and C: control). Each 80 specimens (40 demineralised and 40 sound) were varnished with either Mirafluorid or Duraphat or remained unfluoridated (controls). The other specimens were used for measuring base-line fluoride content of the respective tooth. Each six specimens (three demineralised and three sound) were fixed in intraoral appliances worn for 5 days by 10 volunteers in three series (A-C). During the experiment, the samples were brushed twice daily with fluoridated toothpaste. KOH-soluble and structurally bound fluoride (0-30 and 31-60 microm depth) was determined immediately, 1, 3 and 5 days after fluoridation. Fluoride uptake was calculated as compared to base-line content and statistically analysed. Immediately after fluoridation, uptake of KOH-soluble and structurally bound fluoride was similar for Mirafluorid and Duraphat in both demineralised and sound enamel. However, at day 1, 3 and 5 statistically significantly higher amounts of KOH-soluble and structurally bound fluoride were found in the samples treated with Duraphat. For Mirafluorid only the uptake for KOH-soluble fluoride and structurally bound fluoride in the first enamel layer (0-30 microm) of the demineralised samples was significantly higher compared to the controls (C). It is concluded that the novel fluoride varnish Mirafluorid deposits less KOH-soluble and structurally bound fluoride on both demineralised and sound enamel compared to Duraphat under in situ-conditions.     

NovaMin脱敏效果的体内外研究

目的 通过体内外研究,探讨NovaMin脱敏作用的效果以及影响因素.方法 牙本质过敏症的患者随机分为两组.试验组使用含NovaMin成分的含氟牙膏,对照组使用单一含氟牙膏,进行1周的治疗,分别记录治疗前后敏感牙齿的视觉模拟评分法(VAS)值,比较两组间的差异.体外实验将离体牙暴露牙本质,用37%磷酸凝胶酸蚀处理后分为4组,A组:放置于人工唾液中保存7天;B组:用电动牙刷蘸取包含NovaMin的含氟牙膏刷牙本质表面;C组:用包含NovaMin的含氟牙膏涂布于牙本质表面;D组:用电动牙刷蘸取单一含氟牙膏刷牙本质表面.B、C、D组标本的处理均为每天2次,每次5分钟,持续7天.扫描电镜观察牙本质表面,计算牙本质小管封闭数目比.采用单因素方差分析比较各组小管口封闭率.结果 两组患者的VAS值较治疗前均有显著降低(P<0.05),试验组降低更显著(P<0.01).体外试验A组牙本质小管完全开放,B、C、D组牙本质小管封闭数目比分别为(67.02±14.58)%、(82.79±16.61)%、(14.32±7.29)%,三组间两两比较,差异均有统计学意义(P<0.05).结论 含有NovaMin成分的含氟牙膏比单一含氟牙膏能在牙本质表面形产生更好的封闭效果.延长局部涂抹时间及减少敏感区的机械摩擦,可增强其疗效.     

Effect of toothbrushing on fluoride release of polyacid-modified composite resins

The aim of the study was to evaluate the fluoride release of polyacid-modified composite resins (Dyract, Compoglass) submitted to brushing abrasion. Twenty samples were taken from each material and stored in a buffer solution (pH 4.0) for 12 days. Each day, the samples were transferred to a fresh solution. Ten samples of each material were brushed in an automatic tooth-brushing machine (250 strokes, 260-g load) every fourth day. The remaining samples were not subjected to brushing. Fluoride content of the solutions was measured with a fluoride sensitive electrode after the addition of TISAB. Statistical analysis demonstrated significant differences between the two materials with regard to cumulative fluoride release within the 12 days of the experiment. However, no difference was observed between the fluoride release of the brushed samples compared to the unbrushed specimens. This was true for both, the cumulative fluoride release and its release on the day following brushing. It is assumed that regular brushing of the tested materials did not influence their release of fluoride and that brushing of polyacid-modified composite resins does not lead to maintaining their initially high level of fluoride release. Received: 6 May 1999 / Accepted: 21 July 1999     

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     

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     

含氟牙膏对固定矫治中牙釉质脱矿预防效果的研究

目的：探讨含氟牙膏在正畸固定矫治中对预防牙釉质脱矿的作用。方法本实验通过常规口腔卫生宣教指导接受固定矫治器治疗的患者分别使用不同种牙膏刷牙,将患者随机分为氟化物组和对照组,氟化物组采用含氟牙膏刷牙,对照组采用不含氟牙膏刷牙,应用时间平均18个月。分别比较矫治前后两组患者及被观察牙齿牙釉质脱矿发病率和脱矿程度,判断含氟牙膏在固定矫治中对牙釉质脱矿的预防效果。结果在正畸固定矫治中,应用氟浓度为0．15%的含氟牙膏刷牙,可明显降低牙釉质脱矿的发病率,明显减少牙釉质3度脱矿的发生。结论0．15%含氟牙膏应用于固定矫治能够降低牙釉质脱矿的程度。     

Deposition of fluoride on enamel surfaces released from varnishes is limited to vicinity of fluoridation site

The aim of the in-situ study was to determine fluoride uptake in non-fluoridated, demineralized enamel after application of fluoride varnishes on enamel samples located at various distances from the non-fluoridated samples. All enamel samples used were demineralized with acidic hydroxyethylcellulose before the experiment. Intra-oral appliances were worn by ten volunteers in three series: (1, Mirafluorid, 0.15% F; 2, Duraphat, 2.3% F and 3, unfluoridated controls) of 6 days each. Each two enamel samples were prepared from 30 bovine incisors. One sample was used for the determination of baseline fluoride content (BFC); the other was treated according to the respective series and fixed in the intra-oral appliance for 6 days. Additionally, from 120 incisors, each four enamel samples were prepared (one for BFC). Three samples (a–c) were placed into each appliance at different sites: (a) directly neighboured to the fluoridated specimen (=next), (b) at 1-cm distance (=1 cm) and (c) in the opposite buccal aspect of the appliance (=opposite). At these sites, new unfluoridated samples were placed at days 1, 3 and 5, which were left in place for 1 day. The volunteers brushed their teeth and the samples with fluoridated toothpaste twice per day. Both the KOH-soluble and structurally bound fluoride were determined in all samples to determine fluoride uptake and were statistically analyzed. One day, after fluoridation with Duraphat, KOH-soluble fluoride uptake in specimen a (=next) was significantly higher compared to the corresponding samples of both the control and Mirafluorid series, which in turn were not significantly different from each other. At all other sites and time points, fluoride uptake in the enamel samples were not different from controls for both fluoride varnishes. Within the first day after application, intra-oral-fluoride release from the tested fluoride varnish Duraphat leads to KOH-soluble fluoride uptake only in enamel samples located in close vicinity to the fluoridation site.     

A study in vitro of the combined effects of soft drinks and tooth brushing with fluoride toothpaste on the wear of dentine

The aim of this study was to measure loss of dentine produced by soft drinks alone and combined with tooth brushing with and without toothpastes. Groups of flat human dentine specimens were exposed for 10 min and then 30 min to orange juice (OJ), carbonated cola (CC) or modified blackcurrant (MB) drinks alone or after the exposures brushed with a fluoride toothpaste for 10 s. Further groups were exposed to OJ as before but brushed with water or non-fluoride toothpaste or placed in slurries of fluoride paste. Five cycles of each regimen were carried out. Tissue loss was determined by profilometry. Water immersion/brushing and brushing controls were included. OJ and CC produced similar erosion and significantly more than MB. Compared with drinks alone, dentine loss was reduced by fluoride toothpaste brushing but increased by water and non-fluoride toothpaste brushing. Fluoride toothpaste slurry had no significant effect on soft drink erosion. Very little abrasion with brushing alone was recorded over the time frame of these experiments. It is concluded that fluoride toothpaste could provide protection, albeit small, against erosion. The data again support the concept of brushing before meals.     

Evaluation of the anticaries benefit of fluoride toothpastes using an enamel insert model

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.