Efficacy of accelerated aging methods to degrade the adhesive interface of dentin cavities bonded with etch-and-rinse adhesive systems

This study evaluated the bond durability produced by etch-and-rinse (E&R) adhesive systems in response to traditional and accelerated aging methods. Tridimensional dentin cavities were prepared on 80 bovine incisors, which were bonded with a 3-step E&R (Adper Scotchbond Multipurpose Plus – MP) and a 2-step E&R (Adper Single Bond 2 (SB) adhesive systems, and restored with composite. The samples were stored in water for 24 h, and then subjected to each of the aging methods (n = 10): control group – only 24-h storage (not exposed to additional aging), 6- and 12-month water storage, and 10% NaOCl storage. The push-out bond strength test was performed in a universal testing machine. Failure modes were evaluated by scanning electron microscopy. Data were analyzed by two-way ANOVA and Tukey tests (p < 0.05). Aging methods provided statistically similar bond strength for 3-step E&R adhesive system (p > 0.05). 10% NaOCl storage provides statistically similar bond strength values to 6- and 12-month water storage (p > 0.05), which were statistically lower than those provided by 24-h water storage (control group) (p < 0.05). Adhesive failures were more frequent. Aging methods provided different behaviors according to each adhesive system. The accelerated 10% NaOCl storage was effective to decrease bond strength only for 2-step E&R adhesive system.     

Bond strength and durability of universal adhesive agents with lithium disilicate ceramics: A shear bond strength study

The aim was to assess the shear bond strength (SBS) of lithium disilicate (LD) ceramic to resin composite with different universal adhesives, duration of ageing and silane. One hundred and twenty LD ceramic discs were processed, fired and etched (HF acid 5%) for 20 s (sec). All specimens were divided into 12 groups (n = 10), based on different combinations of, 3 different universal adhesives [Scotchbond (SB) Universal Adhesive, All-Bond (AB) Universal, and Futurabond U (FU)], silane and different duration of ageing [24 h and 3 months]. Composite resin cylinders (Tetric ceram) (3mm × 2 mm) were formed using bonding jig on ceramic and were light-cured. The specimens in groups 1–6 and 7–12 were stored in distilled water (37 °C) for 24 h and 3 months (thermocycling -5000 cycles 5–55 °C/30 s dwell time) before being subjected to bond strength testing respectively. Using universal testing machine shear bond test was performed at a crosshead speed of 1 mm/min. Failure modes and fracture patterns were assessed using stereomicroscope and scanning electron microscope. Analysis of variance was performed to analyze data. SBS was significantly higher with silane than without silane (p < 0.01), regardless of the type of adhesive or storage duration. Specimens tested at 24 h storage showed significantly higher (p < 0.01) SBS than specimens tested after 3-months. A comparison among different universal adhesives showed significantly distinct bond strength (p < 0.01). Optimal bonds to LD were achieved by application of silane. While ageing through storage had a negative impact on the SBS, it varied among different adhesives.     

One-year bonding performance of one-bottle etch-and-rinse adhesives to dentin at different moisture conditions

Abstract

This study aimed to investigate the one-year bond strengths to dentin of one-bottle etch-and-rinse adhesive systems applied under different moisture conditions. Class V cavities were prepared in bovine incisors and randomly allocated (n?=?8) according to the type of adhesive system used – SB (Adper? Single Bond 2); PB (Prime & Bond 2.1); and XPB (XP Bond) – and the moisture condition kept in the cavity – moist, over-wet, and over-dry. Filtek? Z250 was used for teeth restoration. Specimens for microtensile bond strength (µTBS) test were obtained and stored in water for 24?h or 1?year, and submitted to mechanical testing. Data were analyzed using t-tests, ANOVA and the Holm–Sidak post hoc test (α?=?0.05). Weibull analysis was used to verify the reliability of specimens. The type of adhesive and the moisture condition of the substrate affected the µTBS. At 24?h, SB performed better under the moist and over-wet conditions. At 1?year, SB, PB, and XPB showed the greatest percentage reduction at the moist (～38%), over-wet (100%), and over-dry (100%) conditions, respectively. The reliability of adhesives was affected by the variable factors tested. In conclusion, the solvent composition of adhesives and the moisture condition of the substrate play an important role in the bond strength and bonding stability of resin-based restorations, as well as on the reliability of the adhesive interfaces over time.     

Bonding performance of a temporary tooth coating material to enamel

This study aimed to evaluate the bond characteristics of 6-MHPA monomer-based primer in a temporary tooth coating material set (BeautiCoat, Shofu, Kyoto, Japan), applied to various conditioned enamels. The buccal enamel of thirty premolars was ground flat and the teeth were divided into six groups. This research bleached two groups, acid-etched two groups, and did not condition the remaining two groups. BeautiCoat primer was applied alone, or with activator on the ground and bleached enamel. BeautiCoat primer and FL-Bond were applied on the acid-etched enamel. FL-Bond adhesive on acid-etched enamel served as the control. BeautiCoat flowable resin was then piled on the enamel surfaces and light-cured. The microtensile bond strength (μTBS) was measured and the superficial demineralization, the resin–enamel interface, and failure mode were evaluated with a scanning electron microscope. The μTBS obtained in the non-acid-etched groups was more than half of that obtained in the acid-etched groups (p < 0.05). FL-Bond adhesive on acid-etched enamel showed the highest μTBS values. Marked improvements in μTBS were not observed when activator was combined with primer. No significant difference in μTBS could be found between BeautiCoat primer and FL-Bond adhesive on acid-etched enamel, or among BeautiCoat primer applied with/without activator on the ground and bleached enamel. The cohesive enamel failure ratio was low with the BeautiCoat primer or in the primer and activator groups but high in the FL-Bond group. The adhesive of BeautiCoat provided favorable bond strength with minimal risk of damage to the enamel.     

The Interlaminar Bond Strength of Flexible Polymer-Metal Laminates

An alternative test method to the traditional 180° “T” peel test has been developed for the measurement of interlaminar bonding in three-ply (polyester/aluminium/polypropylene) flexible-packaging, laminate materials. The new test is thought to involve mixed mode I (opening) and mode II (shearing) failure, and takes into account the yielding of the polypropylene layer during testing. The method allows more direct comparisons between materials to be made, and allows the measurement of strong bonds, where a peel test would result in yield or fracture of the substrate arms before debonding.     

The Interlaminar Bond Strength of Flexible Polymer-Metal Laminates

An alternative test method to the traditional 180° “T” peel test has been developed for the measurement of interlaminar bonding in three-ply (polyester/aluminium/polypropylene) flexible-packaging, laminate materials. The new test is thought to involve mixed mode I (opening) and mode II (shearing) failure, and takes into account the yielding of the polypropylene layer during testing. The method allows more direct comparisons between materials to be made, and allows the measurement of strong bonds, where a peel test would result in yield or fracture of the substrate arms before debonding.     

工艺条件对拉伸试件粘接强度分散性的影响

以铝和丁基橡胶的粘接拉伸试件为研究对象,结合粘接过程被粘面表面处理、涂胶、加压、固化等主要工序,讨论了粘接工艺方式和粘接过程控制对拉伸试件粘接强度分散性的影响。结果表明,在粘接过程中采用适当的表面处理方法、涂胶方式,确定适当的加压压力、涂胶厚度和固化条件,有利于减小粘接件拉伸强度数据的分散性并提高粘接强度。     

工艺参数对低粘度建筑结构胶粘接强度的影响

对影响建筑结构胶粘接强度的各工艺参数进行了试验研究,确定了低粘度结构胶最佳固化工艺参数,并结合工程施工提出相应解决措施。     

固化工艺参数对胶粘剂180°剥离强度的影响

以自制胶粘剂为基础,研究了剥离强度测试用样条的制备工艺对180°剥离强度的影响。结果表明:样条制备时的温度、压力、时间、胶层厚度和被粘材料表面粗糙度等因素对剥离强度影响较大,并且有一定的规律性,说明对每种胶粘剂的剥离强度测试,除统一测试标准外,还需研究测试用样条的适宜制备工艺,以降低剥离强度的测试误差。     

Vaporized solvent bonding of polymethyl methacrylate

This investigation highlights rationale of vaporized solvent bonding for fabrication of transparent polymers such as polymethyl methacrylate (PMMA) in terms of optical transparency and bond strength. Vaporized solvent bonding is employed to fabricate the polymer, and its bonding characteristics with appropriate solvents are analyzed. It is observed that chloroform exhibits superior bonding characteristics in comparison with other solvents such as acetone, ethanol, and dichloromethane. In order to see the effect of prior surface modification carried out by ultraviolet (UV) irradiation and low-pressure plasma, surface energy of the polymer was estimated. It is observed that due to surface modification of PMMA by UV irradiation and low-pressure plasma, surface energy of the polymer increases considerably. However, due to exposure under UV irradiation and low-pressure plasma, molecular weight of PMMA decreases and atomic force microscopy (AFM) studies reveal that the topography of PMMA changes significantly resulting in deterioration of vaporized solvent bonding strength. Therefore, in the case of vaporized solvent bonding, increase in surface energy of the polymer is not a primary factor rather retention of molecular weight is more necessary.     

Effect of Different Application Techniques of All-in-One Adhesives on Microtensile Bond Strength to Sound and Caries-Affected Dentin

The aim of this study was to evaluate the microtensile bond strength of two all-in-one self-etch adhesives applied to sound and caries-affected dentin with four different application techniques. Forty extracted third molars with occlusal caries were randomly divided into four groups for G-Aenial Bond and S3 Bond: (1) according to manufacturer's instructions; (2) with acid etching before applying adhesives; (3) doubling adhesive application time; and (4) doubling adhesive coating. Teeth were sectioned to obtain 1-mm- ± 0.2-mm-thick dentin sticks and subjected to a tensile force. For G-Aenial Bond, doubling the time and application of two consecutive coats produced significantly higher strength than that obtained by following manufacturers' instructions and acid etching application to sound dentin. Prior acid etching and application of two consecutive coats to caries-affected dentin generated significantly higher bond strength than that using other techniques. For S3 Bond, there was no significant difference between application techniques in caries-affected dentin. For sound dentin, double-time application of S3 Bond produced significantly higher strength than application according to the manufacturers' instructions. Compared to the application according to manufacturer's instructions, acid etching before applying adhesives, doubling application time, and doubling the coating had a positive effect on bond strength to caries-affected dentin for all-in-one adhesives.     

金属与橡胶粘接用双组份胶液的研制

研制了一种酚醛-丁腈橡胶型双组份胶液,主要应用于橡胶与金属之间、橡胶与橡胶之间及橡胶与其他非金属材料之间的胶接。该胶既可以冷粘、又可以热硫化粘接;且粘接强度较高、耐介质、耐老化等综合性能优良。     

双组分黏合剂对聚脲层间黏结强度影响因素的研究

探讨了基材表面粗糙度、层间黏合剂养护龄期、环境温度和湿度对聚脲层间黏结强度的影响规律.实验结果表明：打磨处理后聚脲层间的黏结强度普遍提高;层间黏合剂养护龄期在2～4 h之间,黏结强度较高,在4.2～4.8 N/mmm范围内;随着环境温度的升高,黏结强度增大,高温下达到4.8 N/mm;环境湿度小时可获得较高的黏结强度.     

用X射线仪热分析仪研究影响磷酸氧化铜胶的粘接强度因素

用X射线粉末衍射仪和综合热分析仪对不同固化用具、不同固化温度的YW -Ⅰ磷酸氧化铜无机胶进行较系统分析、研究 ,找出了影响粘接强度的因素。     

服装面料用聚氨酯胶黏剂的研制

介绍了用扩链剂A、混合多元醇和异氰酸酯等材料合成了适合服装面料行业所需的聚氨酯胶黏剂。简单介绍了聚酯多元醇和聚氨酯的合成工艺。研究讨论了多元醇的类型、扩链剂的结构、异氰酸酯指数、溶剂等方面对聚氨酯胶黏剂性能的影响。最终确定的以混合多元醇、扩链剂A、异氰酸酯和混合溶剂等原料合成的聚氨酯胶黏剂其外观澄清透明、软化点在1 0 0～ 1 1 0℃、固含量 35 %时黏度在 1 0 0 0 0～ 2 0 0 0 0mPa·s之间、硬度为 70～ 80邵氏A ,且贮存稳定     

四种原料生物油-酚醛树脂胶粘剂特性研究

利用生物质快速热解液化产物制备燃料或化工产品已成为国内外的研究热点。将四种生物质原料(落叶松、杨木、棉秸秆和玉米秸秆)快速热解液化产物作为苯酚替代物,由此制备出不同种类的热解生物油-PF(酚醛树脂)胶粘剂,并探讨了胶粘剂胶接强度与热解生物油组成的关系。结果表明:落叶松热解生物油-PF胶粘剂的胶接强度最大(1.277 MPa),玉米秸秆热解生物油-PF胶粘剂的胶接强度最小(1.021 MPa);胶粘剂的胶接强度主要与热解生物油中酚类物质含量有关。     

稀释剂对有机玻璃粘接用UV固化胶黏剂的影响

活性稀释剂对uv固化反应过程有重要的影响。为了考察稀释剂对有机玻璃粘接用uV固化胶的影响,采用复配法重点考察了稀释剂的种类、含量配比、表面张力等对有机玻璃粘接用uV胶黏剂的粘接性能的影响。结果表明,采用单官能团稀释剂IBOA和双官能团稀释剂TPGDA进行复配,其混合比例控制在（1：1）,总量控制在胶黏剂的50％一55％对有机玻璃的粘接效果最佳。