The effect of silver fluoride and potassium iodide on the bond strength of auto cure glass ionomer cement to dentine

BACKGROUND: Diamine silver fluoride (Ag(NH3)2F), referred to as AgF, has been shown to reduce the incidence of caries in primary dentitions. The clinical application of this material has been limited by staining associated with both teeth and restorative materials. The application of potassium iodide (KI) after AgF eliminates stain formation. There is a lack of information as to how the addition of AgF followed by KI may affect the bond strength to dentine. The purpose of this study was to compare the bond strengths of auto cure glass ionomer cement to dentine surfaces that had been treated with AgF and KI and without treatment. METHODS: Ten recently extracted human third molars were embedded into methyl methacrylate resin and sliced to form a square block of exposed dentine surfaces. Each of the four surfaces were treated by one of the following procedures: (a) etching with 37 per cent phosphoric acid; (b) applying GC dentine conditioner; (c) etching, followed by application of AgF/KI then washing off the precipitate and air drying; and (d) etching, applying AgF/KI and air drying the reaction products on the surface. Fuji VII auto cure glass ionomer cement was bonded onto each sample and fracture tested. RESULTS: The dentine samples treated with AgF/KI followed by washing away the precipitate and air drying had bond strengths (2.83 MPa) not significantly different from samples that had been conditioned (2.40 MPa). Samples where the AgF/KI precipitate had been air dried onto the dentine surface had significantly lower bond strengths (1.49 MPa) than the washed samples. Samples that were etched had significantly lower bond strengths (1.91MPa) than the conditioned samples. CONCLUSIONS: This study found that the application of AgF/KI to etched dentine samples followed by washing off the precipitate, created bond strengths that were not significantly different to conditioned samples. Leaving the AgF/KI precipitate on the dentine surface significantly reduced the bond strength of auto cured glass ionomer cement to dentine. Washing away the reaction products and air drying is recommended as the clinical protocol for using AgF and KI on dentine surfaces prior to application of an auto cure glass ionomer cement.     

光固化树脂加强型玻璃离子水门汀粘结性能的研究

目的　了解光固化树脂加强型玻璃离子水门汀在不同条件下的粘结性能 ,探讨一种更简便 ,不太注意污染的粘结方法。方法　 10 5颗因正畸原因拔除的健康双尖牙分成七组 ,在不同条件下 (酸蚀 /百酸蚀后干燥 /被水或唾液污染 )粘结脱槽 ,做冷热循环实验后 ,测剪切强度及粘结剂残余指数。结果　光固化树脂加强型玻璃离子水门汀可以替代复合树脂粘结剂 ,不要求严格隔湿。     

光固化树脂加强型玻璃离子水门汀即刻剪切强度的测定

目的研究光固化树脂加强型玻璃离子水门汀黏结正畸托槽的即刻剪切强度。方法收集离体前磨牙30颗,随机均分为3组。第1组(对照组):35%磷酸酸蚀30 s,冲洗、干燥,涂黏结剂,京津釉质黏结剂黏结托槽。第2、3组:35%磷酸酸蚀30 s,冲洗,湿润,光固化型的Fuji Ortho Lc树脂加强型玻璃离子黏结托槽。第1、2组24 h后测剪切强度,第3组30 min内测剪切强度。托槽去除后统计牙面上的黏结剂残留量。结果第2组的剪切强度高于第3组,差异有显著性;第1、3组间剪切强度差异无显著性。结论光固化树脂加强型玻璃离子水门汀的即刻黏结强度能够满足临床要求,但24 h后的黏结强度显著增强。     

Enhancement of fluoride release from glass ionomer cement following a coating of silver fluoride

BACKGROUND: This study investigated the extent to which a coating of 10% silver fluoride (AgF) on discs of glass jonomer cements (GIGs) would enhance the release of fluoride ion into eluting solutions at varying pH. MATERIALS AND METHODS: Forty discs each of Fuji LX, Fuji VII and of Vitrebond were prepared in a plastic mould. Twenty discs of each material were coated for 30 seconds with a 10% solution of AgF. Five discs each of coated and uncoated material were placed individually in 4m1 of differing eluant solutions. The eluant solutions comprised deionized distilled water (DDW) and three separate acetate buffered solutions at pH 7, pH 5 and pH 3. After 30 minutes the discs were removed and placed in five vials containing 4m1 of the various solutions for a further 30 minutes. This was repeated for further intervals of time up to 216 hours, and all eluant solutions were stored. Fluoride concentrations in the eluant solutions were estimated using a fluoride specific electrode, with TISAB IV as a metal ion complexing and ionic concentration adjustment agent. Cumulative fluoride release patterns were determined from the incremental data. RESULTS: The coating of AgF greatly enhanced the level of fluoride ion release from all materials tested. Of the uncoated samples, Vitrehond released the greater concentrations of fluoride ion, followed by Fuji VII. However, cumulative levels of fluoride released from coated samples of the GICs almost matched those from coated Vitrebond. CONCLUSIONS: It was concluded that a coating of 10% AgF on GICs and a resin modified GIC greatly enhanced the concentration of fluoride released from these materials. This finding might be applied to improving protection against recurrent caries, particularly in high caries risk patients, and in the atraumatic restorative technique (ART) of restoration placement.     

Ion uptake into demineralized dentine from glass ionomer cement following pretreatment with silver fluoride and potassium iodide

BACKGROUND: Diamine silver fluoride (Ag(NH3)2F), referred to as AgF, has been shown to provide a pronounced antimicrobial action against caries. The clinical application of this material has been limited by the staining associated with both teeth and tooth coloured restorative materials. The application of potassium iodide (KI) after AgF eliminates stain formation. The purpose of this study was to determine if a prior application of silver fluoride and potassium iodine to demineralized dentine affected the uptake of strontium and fluoride from a glass ionomer cement restoration. METHOD: Three cavities were prepared in each of five recently extracted human third molars. The cavities were demineralized and treated as follows. In each tooth, one cavity was left as a control, one cavity was restored with glass ionomer cement and one cavity was treated with 1.8M AgF and a saturated KI solution and then restored with glass ionomer cement. The penetration of the various elements into demineralized dentine was measured by their relative percentage weights using electron probe microanalysis (EPMA). RESULTS: Fluoride uptake was significantly higher in the AgF and KI treated samples compared to the other two samples and significantly higher in the glass ionomer restored sample compared to the control. The application of AgF and KI did not significantly interfere with the transfer of strontium from glass ionomer cement into dentine. Silver and iodine deposits were present in the demineralized dentine treated with AgF and KI. CONCLUSIONS: The application of AgF and KI onto dentine prior to the placement of glass ionomer cement did not significantly affect the strontium uptake into the subjacent demineralized dentine and the fluoride levels in this zone were significantly increased.     

树脂加强型玻璃离子粘固剂粘结强度的研究

目的 检测树脂加强型玻璃离子粘固剂的粘结强度,探讨影响粘结性能的相关因素.方法 30颗健康离体前磨牙分成两组,分别用京津釉质粘合剂和树脂加强型玻璃离子粘固剂初次、二次粘接托槽,测剪切强度及粘结剂残余指数.结果 树脂加强型玻璃离子粘固荆的粘结强度与临床普遍使用的京津釉质粘合剂的粘结强度相近,差异无显著性(P>O.05).结论 树脂加强型玻璃离子粘固剂可以替代复合树脂粘结剂.能够满足临床需要.     

树脂修饰化玻璃离子托槽粘结剂粘结强度的体外研究

目的：评估一种树脂修饰化的玻璃离子托槽粘结剂在牙面不同处理方式和环境下的两次粘结后的剪切强度情况。方法：将新近拔除的105颗上颌第一前磨牙随机均分成7组,按照说明书的要求完成托槽的粘结。对照组牙面用37%的磷酸处理后,用光固化复合树脂粘结剂（3M,Transbond XT）粘结。其它6组牙面分别在37%的磷酸、GC处理剂（GC Self-Conditioner）、和不做任何处理的条件下,分别在干燥和湿润的环境下用树脂修饰化的玻璃离子（RMGIC;Fuji ORTHO LC,GC Corporation,Tokyo,Japan）粘结,所有牙齿均选用同种托槽。托槽粘结24 h后,在万能测力机下以1 mm/min的速度卸载,并记录下数值。除去牙面和托槽底面多余粘结剂后,重复上述过程。每次卸载后检查牙釉质损坏情况。结果：对照组两次剪切强度有较小的差异,其它GC玻璃离子粘结剂组两次剪切强度没有统计学意义。GC粘结剂不做任何处理组在干燥和湿润的环境下其剪切强度存在明显的差异。干燥环境下,37%的磷酸和GC处理剂处理后,GC粘结剂组两次卸载后的牙釉质均出现不同程度的釉裂或釉质脱落。结论：这种树脂修饰化的玻璃离子粘结剂可以在多种条件下用于托槽的粘结。     

不同剂型玻璃离子水门汀对牙本质粘结剪切强度的比较

目的:比较不同剂型玻璃离子水门汀对牙本质粘结剪切强度,为临床使用提供参考。方法:临床收集新鲜拔除的磨牙30个,用慢速精密齿科片切机切取颊面浅层牙本质薄片(片厚2 mm),自凝塑料包埋,仅暴露颊侧浅层面作为粘结面,流水冲洗4 s,无油气体吹干,于每个试件的粘结面上固定一直径4 mm,高2 mm成型管。然后将30个试件随机分为3组(每组10个),分别使用RelyXTM Luting Cement(粉液剂型)、GC Fuji PLUS(粉液剂型)和GC Fuji CEM(双糊剂型)3种玻璃离子水门汀进行充填,制作粘结试件后,试件置于盛有人工唾液的容器中37℃24 h,用万能测试机测定每个试件的粘结剪切强度。结果:3种玻璃离子水门汀的粘结剪切强度由底到高分别为:RelyXTM Luting Cement(粉液剂型)(6.163±1.177)MPa、GC Fuji PLUS(粉液剂型)(8.004±0.962)MPa、GC Fuji CEM(双糊剂型)(10.31±0.893)MPa,三者间差异有统计学意义(P<0.05)。结论:双糊剂型玻璃离子水门汀抗粘结剪切强度明显高于两种粉液剂型玻璃离子水门汀,是临床修复治疗的良好选择。     

3种树脂表面处理技术对树脂核-玻璃离子水门汀粘接强度影响的实验研究

目的 比较3种表面处理的树脂核与玻璃离子水门汀间的剪切粘接强度,为临床上设计树脂核-全冠修复体时冠的粘接提供理论依据。方法 将30个树脂核试件块随机分为3组：金刚砂车针打磨（RDB）组、RDB加酸蚀剂酸蚀（RDBE）组、RDB加树脂粘接剂（RDBA）组,分别接受金刚砂车针打磨、RDB加酸蚀剂酸蚀、RDB加树脂粘接剂3种表面处理。将各组树脂核与玻璃离子水门汀粘接,经37 ℃恒温水浴24 h后,测试分析各组的剪切粘接强度,并通过扫描电镜依次观察树脂核表面形貌、粘接界面及粘接断面,记录粘接面破坏形式。结果 3组的树脂核表面形貌及粘接界面形貌不同,而粘接断面的断裂方式无统计学差异（P>0.10）。RDB组、RDBE组、RDBA组试件的剪切强度分别为（4.28±0.18）、（4.65±0.17）、（2.39±0.21）MPa,3组间的剪切强度具有统计学差异（P<0.01）。结论 树脂核表面处理对其与玻璃离子水门汀间的剪切粘接强度有影响。     

含不同浓度氟化钠的酸蚀液对托槽抗剪粘接强度的影响

医科大学附属口腔医院　正畸科,辽宁　沈阳110002;2.泰山齿科　正畸科,辽宁　沈阳110032) [摘要]　目的　在确保托槽粘接强度的条件下,探讨35%磷酸酸蚀液中添加氟化钠的最佳浓度。方法　64颗离体 牙随机分成A、B、C组和对照组,分别采用添加4种不同浓度氟化钠(1·23%、2%、3%和0%)的酸蚀液进行酸蚀并 常规粘接托槽,于1周、4周、12周和24周分别从每组样本中随机抽取4颗牙进行抗剪粘接强度测试,并观测托槽 脱落后界面粘接剂残留情况,记录粘接材料残留指数(ARI)。结果　A、B、C组和对照组的抗剪粘接强度在4个观 测时间点进行组内比较均无统计学差异,组间比较则有统计学差异,C组低于其他3组(P<0·05)。4组间ARI分 值无统计学意义。结论　35%磷酸酸蚀液中添加不高于2%的氟化钠,与单纯应用35%磷酸的粘接效果相似;当氟 化钠浓度高于3%后,托槽的抗剪粘接强度下降。     

氟化氨银溶液对人工脱矿牙本质粘接强度的影响

目的：评价氟化氨银溶液（silver diammine fluoride,SDF）对人工龋牙本质和玻璃离子粘固剂（glass ionomer cement,GIC）之间的微拉伸粘接强度的影响。方法：将12颗人离体磨牙制备成脱矿牙本质和未脱矿牙本质2组标本,均分为对照组、氟化氨银组及氟化氨银与光固化联合处理组（n ＝20）,将处理完成的牙本质与 GIC 富士 IX 粘接,24 h 后对标本进行切割及微拉伸强度试验,最后用扫描电镜观察牙本质与 GIC 之间的超微结构,并进行数据统计分析。结果：脱矿后牙本质的粘接强度显著高于未脱矿的牙本质（P ＜0．01）。经过光固化 SDF 处理的人工龋牙本质的粘接强度数值显著高于只经 SDF 处理的人工龋牙本质的粘接强度（P ＜0．01）。结论：SDF 处理的人工脱矿牙本质与 GIC 之间的微拉伸粘接强度得到显著提高。     

树脂加强型玻璃离子黏结剂黏结力的实验研究

目的 了解光固化树脂加强型玻璃离子水门汀的剪切强度能否满足临床需要;并比较不同条件下其剪切强度的变化.方法 收集离体前磨牙50颗,随机均分为5组.第1组(对照组):35%磷酸酸蚀30s,冲洗、干燥,涂黏结剂,采用京津釉质黏结剂黏结托槽.第2、4组:35%磷酸酸蚀30s,冲洗,湿润,采用光固化型的Fuji Ortho Lc树脂加强型玻璃离子黏结托槽.第3、5组:不酸蚀,采用光固化型的Fuji Ortho Lc树脂加强型玻璃离子黏结托槽.1、2、3组用电子万能实验机测24h的抗剪切强度,4、5组测30 min的抗剪切强度.并统计牙面上的黏结剂残留量.结果 第2、3、4组的抗剪切强度均能满足临床需要,第5组的抗剪切强度不能满足临床需要,第2组的抗剪切强度与其它各组相比差别有显著性.结论 光固化树脂加强型玻璃离子在酸蚀和免酸蚀后24h,以及酸蚀黏结30min后的剪切强度均能满足临床需要;而免酸蚀黏结30min的抗剪切强度不能满足临床需要;酸蚀后光固化树脂加强型玻璃离子的剪切强度明显增强.     

An ex vivo study of arrested primary teeth caries with silver diamine fluoride therapy

Objectives

This ex vivo study compared the physico-chemical structural differences between primary carious teeth biannually treated with silver diamine fluoride (SDF) and carious teeth without such treatment.

Method

Twelve carious primary upper-central incisors were collected from 6-year-old children. Six teeth had arrested caries after 24-month biannual SDF applications and 6 had active caries when there was no topical fluoride treatment. The mineral density, elemental contents, surface morphology, and crystal characteristics were assessed by micro-computed tomography (micro-CT), energy-dispersive X-ray spectrometry (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM).

Results

Micro-CT examination revealed a superficial opaque band approximately 150 μm on the arrested cavitated dentinal lesion. This band was limited in the active carious lesion. EDX examination detected a higher intensity of calcium and phosphate of 150 μm in the surface zone than in the inner zone, but this zone was restricted in the active cavitated dentinal lesion. SEM examination indicated that the collagens were protected from being exposed in the arrested cavitated dentinal lesion, but were exposed in the active cavitated dentinal lesion. TEM examination suggested that remineralised hydroxyapatites were well aligned in the arrested cavitated dentinal lesion, while those in the active cavitated dentinal lesion indicated a random apatite arrangement.

Conclusions

A highly remineralised zone rich in calcium and phosphate was found on the arrested cavitated dentinal lesion of primary teeth with an SDF application. The collagens were protected from being exposed in the arrested cavitated dentinal lesion.

Clinical significance

Clinical SDF application positively influences dentine remineralisation.     

酸蚀时间对树脂加强型玻璃离子粘结性能的影响

目的 比较光固化树脂加强型玻璃离子水门汀和复合树脂在几种粘结条件下，不同酸蚀时间后的粘结强度，探求减少釉质脱钙的粘结方法。方法 120颗因正畸拔除的健康双尖牙分成8组，酸蚀30秒或90秒后在几种条件下(干燥／被水或唾液潮湿)粘结脱槽，做冷热循环实验后，测剪切强度。结果 复合树脂酸蚀90秒较酸蚀30秒的粘接强度明显增强；光固化树脂玻璃在几种粘接条件下酸蚀90秒和酸蚀30秒粘接强度无明显区别，水潮湿组粘接强度最高。结论 复合树脂可通过延长酸蚀时间增加粘接强度；光固化树脂玻璃酸蚀30秒足够，延长酸蚀时闻不能增加粘接强度，白白造成釉质丢失。     

不同类型玻璃离子水门汀氟离子体外释放的比较

目的:比较不同类型玻璃离子水门汀(GIC)在体外释放氟离子的能力.方法:选用同一厂家生产的4种不同类型的GIC为实验对象,分别为树脂改良型GIC(FUJI Ⅱ LC)、传统型GIC(FUJI Ⅱ)、金属加强型GIC(FUJI Ⅸ)、多功能型GIC(FUJI PLUS).使用氟离子选择电极,连续14 d测定GIC固化后标本浸泡溶液中的氟离子浓度,采用光固化树脂(Z100)作为对照组.实验数据采用单因素方差分析和q检验法检验.结果:4种GIC都显现出较高的初期氟离子释放,前2 d氟离子释放量急剧下降,2 d后氟离子释放量缓慢平稳下降.累计氟离子释放量:FUJI Ⅱ LC＞FUJI Ⅱ、FUJI PLUS＞FUJI Ⅸ.结论:树脂改良型GIC具有良好的氟离子释放能力,在预防继发龋上可能具有一定的优势.