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Sample records for adhesively bonded shell

  1. Interface Fracture in Adhesively Bonded Shell Structures

    Jensen, Henrik Myhre

    2007-01-01

    Two methods for the prediction of crack propagation through the interface of adhesively bonded shells are discussed. One is based on a fracture mechanics approach; the other is based on a cohesive zone approach. Attention is focussed on predicting the shape of the crack front and the critical...

  2. Computational Chemistry of Adhesive Bonds

    Phillips, Donald H.

    1999-01-01

    This investigation is intended to determine the electrical mechanical, and chemical properties of adhesive bonds at the molecular level. The initial determinations will be followed by investigations of the effects of environmental effects on the chemistry and properties of the bond layer.

  3. Adhesives for orthodontic bracket bonding

    Déborah Daniella Diniz Fonseca

    2010-04-01

    Full Text Available The advent of acid etching, introduced by Buonocore in 1955, brought the possibility of bonding between the bracket base and enamel, contributing to more esthetic and conservative orthodontics. This direct bracket bonding technique has brought benefits such as reduced cost and time in performing the treatment, as well as making it easier to perform oral hygiene. The aim of this study was to conduct a survey of published studies on orthodontic bracket bonding to dental enamel. It was verified that resin composites and glass ionomer are the most studied and researched materials for this purpose. Resin-modified glass ionomer, with its biocompatibility, capacity of releasing fluoride and no need for acid etching on the tooth structure, has become increasingly popular among dentists. However, due to the esthetic and mechanical properties of light polymerizable resin composite, it continues to be one of the adhesives of choice in the bracket bonding technique and its use is widely disseminated.

  4. Mechanical strength of adhesive-bonding

    In order to meet the prospective application of a GFRP dewar for energy storage system using a large superconducting magnet, the dewar with a complex structure together with a large size are desired to be made. It is difficult to manufacture such a type of the dewars in one united body. These dewars can be manufactured by the adhesive-bonding method. In the present study, the mechanical strength of adhesive-bonding is studied from this point of view. The mechanical strength of the adhesive-bonding has been investigated by the static tensile method and the impact loading method using small test samples. From the static tensile tests, the following results have been obtained. For the sample adhesive-bonded with insertion structure, the mechanical strength of the adhesive-bonding is found to depend on the adhesives used and on the difference of the thermal contraction between the materials which are adhesive-bonded each other. Using a soft adhesive as Araldite 106, the mechanical strength of the adhesive-bonding is small at room temperature, but it remarkably increases at cryogenic temperatures. For a hard adhesive as Araldite 103 and Stycast 2850 FT, it is large at room temperature, and it further increases at cryogenic temperatures. The dewar has to be strong enough not only at cryogenic temperatures but also at room temperature. A soft adhesive is not suitable for constructing the dewar. For the sample adhesive-bonded with screwing structure, the mechanical strength of the adhesive-bonding depends on the shear strength of GFRP itself. The mechanical strength of the adhesive-bonded part increases with the decreasing temperature. Therefore, this screwing method is advantageous for the construction of the dewar. According to the impact loading tests, it is found that the adhesive-bonding of screwing structure is not brittle at cryogenic temperature. This is due to inherent property of GFRP. (J.P.N.)

  5. Characterization of adhesively bonded joints using bulk adhesive properties

    Kon, Haruhiko

    1991-01-01

    Though using bulk adhesive properties to predict adhesively bonded joint response has yet to be proven infallible, based upon the success of previous works, this effort attempts to shed some light on the stresses present in a typical automotive bonded joint. Adhesive material properties obtained in previous works were used in a finite element analysis of a simulated automotive joint to predict the stresses in that joint. The automotive joint analyzed was a simplified repr...

  6. Effect of adhesive thickness on adhesively bonded T-joint

    The aim of this work is to analyze the effect of adhesive thickness on tensile strength of adhesively bonded stainless steel T-joint. Specimens were made from SUS 304 Stainless Steel plate and SUS 304 Stainless Steel perforated plate. Four T-joint specimens with different adhesive thicknesses (0.5, 1.0, 1.5 and 2.0 mm) were made. Experiment result shows T-joint specimen with adhesive thickness of 1.0 mm yield highest maximum load. Identical T-joint specimen jointed by spot welding was also tested. Tensile test shows welded T-Joint had eight times higher tensile load than adhesively bonded T-joint. However, in low pressure application such as urea granulator chamber, high tensile strength is not mandatory. This work is useful for designer in fertilizer industry and others who are searching for alternative to spot welding

  7. Dynamic analysis of two adhesively bonded rods

    Kenneth L. Kuttler

    2009-07-01

    Full Text Available This work presents two models for the dynamic analysis of two rods that are adhesively bonded. The first model assumes that the adhesive is an elasto-plastic material and that complete debonding occurs when the stress reaches the yield limit. In the second model the degradation of the adhesive is described by the introduction of material damage. Failure occurs when the material is completely damaged, or the damage reaches a critical floor value. Both models are analyzed and the existence of a weak solution is established for the model with damage. In the quasistatic case, a new condition for adhesion is found as the limit of the adhesive thickness tends to zero.

  8. Ultrasonic Nondestructive Characterization of Adhesive Bonds

    Qu, Jianmin

    1999-01-01

    Adhesives and adhesive joints are widely used in various industrial applications to reduce weight and costs, and to increase reliability. For example, advances in aerospace technology have been made possible, in part, through the use of lightweight materials and weight-saving structural designs. Joints, in particular, have been and continue to be areas in which weight can be trimmed from an airframe through the use of novel attachment techniques. In order to save weight over traditional riveted designs, to avoid the introduction of stress concentrations associated with rivet holes, and to take full advantage of advanced composite materials, engineers and designers have been specifying an ever-increasing number of adhesively bonded joints for use on airframes. Nondestructive characterization for quality control and remaining life prediction has been a key enabling technology for the effective use of adhesive joints. Conventional linear ultrasonic techniques generally can only detect flaws (delamination, cracks, voids, etc) in the joint assembly. However, more important to structural reliability is the bond strength. Although strength, in principle, cannot be measured nondestructively, a slight change in material nonlinearity may indicate the onset of failure. Furthermore, microstructural variations due to aging or under-curing may also cause changes in the third order elastic constants, which are related to the ultrasonic nonlinear parameter of the polymer adhesive. It is therefore reasonable to anticipate a correlation between changes in the ultrasonic nonlinear acoustic parameter and the remaining bond strength. It has been observed that higher harmonics of the fundamental frequency are generated when an ultrasonic wave passes through a nonlinear material. It seems that such nonlinearity can be effectively used to characterize bond strength. Several theories have been developed to model this nonlinear effect. Based on a microscopic description of the nonlinear

  9. Dynamic strength of molecular adhesion bonds.

    Evans, E; Ritchie, K

    1997-01-01

    In biology, molecular linkages at, within, and beneath cell interfaces arise mainly from weak noncovalent interactions. These bonds will fail under any level of pulling force if held for sufficient time. Thus, when tested with ultrasensitive force probes, we expect cohesive material strength and strength of adhesion at interfaces to be time- and loading rate-dependent properties. To examine what can be learned from measurements of bond strength, we have extended Kramers' theory for reaction k...

  10. Advances in modeling and design of adhesively bonded systems

    Kumar, S

    2013-01-01

    The book comprehensively charts a way for industry to employ adhesively bonded joints to make systems more efficient and cost-effective Adhesively bonded systems have found applications in a wide spectrum of industries (e.g., aerospace, electronics, construction, ship building, biomedical, etc.) for a variety of purposes. Emerging adhesive materials with improved mechanical properties have allowed adhesion strength approaching that of the bonded materials themselves. Due to advances in adhesive materials and the many potential merits that adhesive bonding offers, adhesive bonding has replac

  11. Improved stress prediction in adhesive bonded optical components

    Vreugd, J. de; Voert, M.J.A. te; Nijenhuis, J.R.; Pijnenburg, J.A.C.M.; Tabak, E.

    2012-01-01

    Adhesives are widely used in optomechanical structures for bonding optical components to their mounts. The main advantage of using adhesives is the excellent strength to weight ratio. Adhesive bonding is seen as a desirable joining technique as it allows for greater flexibility in design. A disadvantage of adhesives however is the limited dimensional stability and loadability. To design stable optical mounts, accurate prediction of stresses and deformation is therefore needed. Adhesives show ...

  12. A comparison of shear bond strength of orthodontic brackets bonded with four different orthodontic adhesives

    Sharma, Sudhir; Tandon, Pradeep; Nagar, Amit; Singh, Gyan P; Singh, Alka; Chugh, Vinay K

    2014-01-01

    Objectives: The objective of this study is to compare the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets bonded with four different orthodontic adhesives. Materials and Methods: Eighty newly extracted premolars were bonded to 0.022 SS brackets (Ormco, Scafati, Italy) and equally divided into four groups based on adhesive used: (1) Rely-a-Bond (self-cure adhesive, Reliance Orthodontic Product, Inc., Illinois, USA), (2) Transbond XT (light-cure adhesive, 3M Unitek, CA, U...

  13. Bond Assembly FOD Zones - A Procedure for Assuring Acceptable Adhesion

    Evans, Kurt; Wurth, Laura; Mitchell, Mark

    2009-01-01

    Rocket motor components are primarily assembled by adhesion. a) For example, the RSRM (Reusable Solid Rocket Motor - part of the Space Shuttle Boosters) system contains 10,000 sq ft of bondline area. b) Rocket motors contain a variety of adhesive/substrate bond systems c) Bond system performance requirements also vary. To assemble reliable components, ATK Space Systems and customers invest substantial resources to the study of bond assembly processes. a) Surface and adhesion science; b) Adhesive chemistry; c) Process parameters; d) Contamination effects.

  14. Application of Bonded Joints for Quantitative Analysis of Adhesion

    Jarmila Trpčevská

    2016-01-01

    Full Text Available The performance of hot-dip coated steel sheets is associated with properties of the zinc coatings on steel substrate. For the characterization of the adhesion behaviour of zinc coating on steel various tests were employed. The study was focused on quantification assessment of galvanized coating adhesion to substrates. Methods for evaluation of the bonding strength of zinc coating by the shear strength and the T-peel tests applying four special types of adhesives were used. The experimental tests of bonded joints show that the adhesion of the zinc coating to the substrate was higher than that of the applied adhesive with the highest strength.

  15. Microleakage under orthodontic brackets bonded with different adhesive systems

    Alkis, Huseyin; Turkkahraman, Hakan; Adanir, Necdet

    2015-01-01

    Objective: This in vitro study aimed to compare the microleakage of orthodontic brackets between enamel-adhesive and adhesive-bracket interfaces at the occlusal and gingival margins bonded with different adhesive systems. Materials and Methods: A total of 144 human maxillary premolar teeth extracted for orthodontic reasons was randomly divided into four groups. Each group was then further divided into three sub-groups. Three total-etching bonding systems (Transbond XT, Greengloo and Kurasper ...

  16. Immediate Dentin Bond Strength of Self-etch Dentine Adhesives

    David Lafuente

    2014-02-01

    Full Text Available Purpose: The purpose of this study was to evaluate the immediate bond strength of two sixth generation and two seventh generation dentin bonding agents to superficial dentin. Specimens were prepared to exposed superficial dentin and either Clearfil SE, Clearfil S3, Adper Prompt-l-pop of G-bond was applied over the dentin surface and light cured. Then composite resin was applied to the treated surface and light-cured in two increments. Specimens were tested 15 minutes after they were made for shear bond strength at 0.01 cm/min. Clearfil SE had statistically higher bond strength than the other three adhesives evaluated (42.9 MPa. There was no statistical difference among Clearfil S3, Adper Prompt-l-pop and G-Bond. The dentin adhesive with an application of an acidic primer before the application of the adhesive showed better immediate bond strength.

  17. Neutron imaging inspections of composite honeycomb adhesive bonds

    Numerous commercial and military aircraft, including the Canadian Forces CF188 Hornet, use composite honeycomb structures in the design of their flight control surfaces (FCS). These structures provide excellent strength to weight ratios, but are often susceptible to degradation from moisture ingress. Once inside the honeycomb structure moisture causes the structural adhesive bonds to weaken, which can lead to complete failure of the FCS in flight. There are two critical structural adhesive bonds: the node bond and the filet bond. The node bond is integral to the honeycomb portion of the composite core and is located between the honeycomb cells. The filet bond is the adhesive bond located between the skin and the core. In order to asses overall structural degradation and develop repair procedures, it is important to determine the degree of degradation in each type of bond. Neutron radiography and tomography of the adhesive bonds was conducted at the Royal Military College (RMC) and FRM-II. Honeycomb samples were manufactured from FCS with in-service water ingress. The radiographs and tomograms provided important information about the degree of degradation in the core as well as about which adhesive bonds are more susceptible. The information obtained from this study will help to develop repair techniques and assess the flight worthiness of FCS.

  18. Microleakage under orthodontic brackets bonded with different adhesive systems

    Alkis, Huseyin; Turkkahraman, Hakan; Adanir, Necdet

    2015-01-01

    Objective: This in vitro study aimed to compare the microleakage of orthodontic brackets between enamel-adhesive and adhesive-bracket interfaces at the occlusal and gingival margins bonded with different adhesive systems. Materials and Methods: A total of 144 human maxillary premolar teeth extracted for orthodontic reasons was randomly divided into four groups. Each group was then further divided into three sub-groups. Three total-etching bonding systems (Transbond XT, Greengloo and Kurasper F), three one-step self-etching bonding systems (Transbond Plus SEP, Bond Force and Clearfil S3), three two-step self-etching bonding systems (Clearfil SE Bond, Clearfil Protectbond and Clearfil Liner Bond), and three self-adhesive resin cements (Maxcem Elite, Relyx U 100 and Clearfil SA Cement) were used to bond the brackets to the teeth. After bonding, all teeth were sealed with nail varnish and stained with 0.5% basic fuchsine for 24 h. All samples were sectioned and examined under a stereomicroscope to score for microleakage at the adhesive–enamel and adhesive–bracket interfaces from both occlusal and gingival margins. Statistical Analysis Used: Statistical analyses were performed with Kruskal–Wallis and Wilcoxon signed-rank tests. Results: The results indicate no statistically significant differences between the microleakage scores of the adhesives; microleakage was detected in all groups. Comparison of the average values of the microleakage scores in the enamel–adhesive and adhesive–bracket interfaces indicated statistically significant differences (P < 0.05). The amount of the microleakage was higher at the enamel–adhesive interface than at the bracket-adhesive interface. Conclusions: All of the brackets exhibited some amount of microleakage. This result means that microleakage does not depend on the type of adhesive used. PMID:25713494

  19. Shear bond strength of different retainer wires and bonding adhesives in consideration of the pretreatment process

    Reicheneder, C. (Claudia); Hofrichter, B. (Bernd); Faltermeier, A. (Andreas); P. Proff; Lippold, C. (Carsten); Kirschneck, C.J. (Christian)

    2015-01-01

    Introduction: We aimed to compare the shear bond strength (SBS) of three different retainer wires and three different bonding adhesives in consideration of the pretreatment process of enamel surface sandblasting. Methods: 400 extracted bovine incisors were divided into 10 groups of 20 paired specimens each. 10 specimens of each group were pretreated by enamel sandblasting. The retainer wires Bond-A-Braid™, GAC-Wildcat®-Twistflex and everStick®ORTHO were bonded to the teeth with the adhesives ...

  20. Experimental and numerical investigations on adhesively bonded joints

    Negru, R.; Marsavina, L.; Hluscu, M.

    2016-04-01

    Two types of adhesively bonded joints were experimental and numerical investigated. Firstly, the adhesives were characterized through a set of tests and the main elastic and mechanical properties were obtained. After that, the stress distributions at interface and middle of adhesive layer were determined using a linear elastic FEA. The numerical data were fitted by a power law in order to determine the critical values of intensity of stress singularity.

  1. Application of Bonded Joints for Quantitative Analysis of Adhesion

    Jarmila Trpčevská; Mária Kollárová; Eva Zdravecká; Jana Tkáčová

    2016-01-01

    The performance of hot-dip coated steel sheets is associated with properties of the zinc coatings on steel substrate. For the characterization of the adhesion behaviour of zinc coating on steel various tests were employed. The study was focused on quantification assessment of galvanized coating adhesion to substrates. Methods for evaluation of the bonding strength of zinc coating by the shear strength and the T-peel tests applying four special types of adhesives were used. The experimental te...

  2. Polymer Composition and Substrate Influences on the Adhesive Bonding of a Biomimetic, Cross-Linking Polymer

    Matos-Pérez, Cristina R.; White, James D.; Wilker, Jonathan J.

    2012-01-01

    Hierarchical biological materials such as bone, sea shells, and marine bioadhesives are providing inspiration for the assembly of synthetic molecules into complex structures. The adhesive system of marine mussels has been the focus of much attention in recent years. Several catechol-containing polymers are being developed to mimic the cross-linking of proteins containing 3,4-dihydroxyphenylalanine (DOPA) used by shellfish for sticking to rocks. Many of these biomimetic polymer systems have been shown to form surface coatings or hydrogels, however bulk adhesion is demonstrated less often. Developing adhesives requires addressing design issues including finding a good balance between cohesive and adhesive bonding interactions. Despite the growing number of mussel mimicking polymers, there has been little effort to generate structure-property relations and gain insights on what chemical traits give rise to the best glues. In this report, we examined the simplest of these biomimetic polymers, poly[(3,4-dihydroxystyrene)-co-styrene]. Pendant catechol groups (i.e., 3,4-dihydroxystyrene) were distributed throughout a polystyrene backbone. Several polymer derivatives were prepared, each with a different 3,4-dihyroxystyrene content. Bulk adhesion testing showed where the optimal middle ground of cohesive and adhesive bonding resides. Adhesive performance was benchmarked against commercial glues as well as the genuine material produced by live mussels. In the best case, bonding was similar to cyanoacrylate “Krazy” or “Super” glue. Performance was also examined using low (e.g., plastics) and high (e.g., metals, wood) energy surfaces. Adhesive bonding of poly[(3,4-dihydroxystyrene)-co-styrene] may be the strongest of reported mussel protein mimics. These insights should help us to design future biomimetic systems, thereby bringing us closer to development of bone cements, dental composites, and surgical glues. PMID:22582754

  3. Polymer composition and substrate influences on the adhesive bonding of a biomimetic, cross-linking polymer.

    Matos-Pérez, Cristina R; White, James D; Wilker, Jonathan J

    2012-06-01

    Hierarchical biological materials such as bone, sea shells, and marine bioadhesives are providing inspiration for the assembly of synthetic molecules into complex structures. The adhesive system of marine mussels has been the focus of much attention in recent years. Several catechol-containing polymers are being developed to mimic the cross-linking of proteins containing 3,4-dihydroxyphenylalanine (DOPA) used by shellfish for sticking to rocks. Many of these biomimetic polymer systems have been shown to form surface coatings or hydrogels; however, bulk adhesion is demonstrated less often. Developing adhesives requires addressing design issues including finding a good balance between cohesive and adhesive bonding interactions. Despite the growing number of mussel-mimicking polymers, there has been little effort to generate structure-property relations and gain insights on what chemical traits give rise to the best glues. In this report, we examine the simplest of these biomimetic polymers, poly[(3,4-dihydroxystyrene)-co-styrene]. Pendant catechol groups (i.e., 3,4-dihydroxystyrene) are distributed throughout a polystyrene backbone. Several polymer derivatives were prepared, each with a different 3,4-dihyroxystyrene content. Bulk adhesion testing showed where the optimal middle ground of cohesive and adhesive bonding resides. Adhesive performance was benchmarked against commercial glues as well as the genuine material produced by live mussels. In the best case, bonding was similar to that obtained with cyanoacrylate "Krazy Glue". Performance was also examined using low- (e.g., plastics) and high-energy (e.g., metals, wood) surfaces. The adhesive bonding of poly[(3,4-dihydroxystyrene)-co-styrene] may be the strongest of reported mussel protein mimics. These insights should help us to design future biomimetic systems, thereby bringing us closer to development of bone cements, dental composites, and surgical glues. PMID:22582754

  4. Adhesive Bonding of Aluminium Alloy A5754 by Epoxy Resins

    Ivan Michalec

    2013-01-01

    Full Text Available Joining thin sheets of aluminium and its alloys is a promising area in the field of joining materials. Nowadays, joining methods that do not melt the material itself are increasingly being utilised. This paper deals with adhesive bonding of aluminium alloy A5754 by two-component epoxy resins. Theresults show that joints bonded by Hysol 9466 have appropriate mechanical properties, but that joints bonded by Hysol 9492 have better thermal stability.

  5. Adhesive Bonding of Aluminium Alloy A5754 by Epoxy Resins

    Ivan Michalec; Milan Marônek

    2013-01-01

    Joining thin sheets of aluminium and its alloys is a promising area in the field of joining materials. Nowadays, joining methods that do not melt the material itself are increasingly being utilised. This paper deals with adhesive bonding of aluminium alloy A5754 by two-component epoxy resins. Theresults show that joints bonded by Hysol 9466 have appropriate mechanical properties, but that joints bonded by Hysol 9492 have better thermal stability.

  6. Adhesion between silica surfaces due to hydrogen bonding

    Bowen, James; Rossetto, Hebert L.; Kendall, Kevin

    2016-09-01

    The adhesion between surfaces can be enhanced significantly by the presence of hydrogen bonding. Confined water at the nanoscale can display behaviour remarkably different to bulk water due to the formation of hydrogen bonds between two surfaces. In this work we investigate the role of confined water on the interaction between hydrophilic surfaces, specifically the effect of organic contaminants in the aqueous phase, by measuring the peak adhesive force and the work of adhesion. Atomic force microscope cantilevers presenting hemispherical silica tips were interacted with planar single crystals of silica in the presence of dimethylformamide, ethanol, and formamide; solution compositions in the range 0–100 mol% water were investigated for each molecule. Each molecule was chosen for its ability to hydrogen bond with water molecules, with increasing concentrations likely to disrupt the structure of surface-bound water layers. With the exception of aqueous solutions containing low concentrations of ethanol, all molecules decreased the ability of confined water to enhance the adhesion between the silica surfaces in excess of the predicted theoretical adhesion due to van der Waals forces. The conclusion was that adhesion depends strongly on the formation of a hydrogen-bonding network within the water layers confined between the silica surfaces.

  7. Computed tomography analysis of wood-adhesive bonds

    Modzel, Gunter Georg Rolf

    The importance of wood bonding increased in the last decades due to the increased usage of wood composites whose performance depends to a large extent on the adhesive penetration and subsequent bonding of the adherends. The presented research used XMT (x-ray microtomography) to perform a non-destructive, three-dimensional analysis of the adhesive bondline and wood-structure of Southern yellow pine, Douglas-fir and yellow-poplar samples. A phenol-formaldehyde adhesive was used. The sodium hydroxide catalyst was replaced with rubidium hydroxide during resin formulation. This was done to improve the image contrast. The reconstructions of the wood structure of Southern yellow pine showed tracheids, rays, fusiform rays, resin canals and pits. On the Douglas-fir sample tracheids, pits and rays were displayed clearly. The yellow-poplar images showed vessels, fibers, bordered pits, scalariform sieve plates and rays. The renderings of the adhesive-bondline of Southern yellow pine proved the dominant role of tracheids for the adhesive flow and showed rays as a secondary pathway of adhesive flow. The results revealed no adhesive flow occured through bordered pits, while simple pits permitted some adhesive flow through ray parenchyma. The results for Douglas-fir showed a similar result; the tracheids were the predominant path of adhesive penetration, while rays played a secondary role and no adhesive flow through the pit aperture was visible. The adhesive flow through the microstructure of yellow-poplar wood occured mainly through vessels and also through rays, but no adhesive flow through the pits was directly observed. The segmentation of the images in three phases: void space, cell wall substance and adhesive, enabled the calculation of the effective bondline thickness based on the adhesive, as well as the volumetric measurement of all three elements and their share on the sample volume. Subsequent experiments showed that the exposure of the Southern yellow pine and yellow

  8. Fatigue de-bond growth in adhesively bonded single lap joints

    P K Sahoo; B Dattaguru; C M Manjunatha; C R L Murthy

    2012-02-01

    The fatigue de-bond growth studies have been conducted on adhesively bonded lap joint specimens between aluminium and aluminium with Redux-319A adhesive with a pre-defined crack of 3 mm at the bond end. The correlations between fracture parameters and the de-bond growth data are established using both numerical and experimental techniques. In the numerical method, geometrically non-linear finite element analyses were carried out on adhesively bonded joint specimen for various de-bond lengths measured from the lap end along the mid-bond line of the adhesive. The finite element results were post processed to estimate the SERR components $G_I$ and $G_{II}$ using the Modified Virtual Crack Closure Integral (MVCCI) procedure. In experimental work, specimens were fabricated and fatigue de-bond growth tests were conducted at a stress ratio $R = −1$. The results obtained from both numerical analyses and testing have been used to generate de-bond growth curve and establish de-bond growth law in the Paris regime for such joints. The de-bond growth rate is primarily function of mode-I SERR component $G_I$ since the rate of growth in shear mode is relatively small. The value of Paris exponent is found to be 6.55. The high value of de-bond growth exponent in Paris regime is expected, since the adhesive is less ductile than conventional metallic materials. This study is important for estimating the life of adhesively bonded joints under both constant and variable amplitude fatigue loads.

  9. Thermoplastic polymeric adhesive for structural bonding applications for orthopaedic devices

    The orthopaedics industry has witnessed tremendous growth in recent years primarily due to the introduction of high performance, porous coated implants. These devices have eliminated the need for the use of bone cement for in vivo implant fixation, replacing it with the ingrowth of bone into the porous surfaces. The metallurgical bonding processes used for attaching the porous to the implant body introduce some undesirable effect i.e., the reduction of the fatigue strength of the implant due to the ''notches'' created and also due to the high temperature exposure during the sintering operations. This paper describes the development of a thermoplastic polymeric adhesive based structural bonding technique. The high performance polymeric adhesive is fully characterized with respect to its intended application. The design of the porous layer is optimized to achieve a reliable bond to the implant. A thermal heating/cooling process was developed to control the final polymer morphology. Static and fatigue tests were conducted to fully characterize the adhesive bond strength. A ring shear test method was developed to determine the shear strength of the bond interface. Besides the characterization of the adhesive bond, the joints will be analyzed using finite element models. The correlation between the analytical models and the

  10. Adhesive Bonding Characterization of Composite Joints for Cryogenic Usage

    Graf, Neil A.; Schieleit, Gregory F.; Biggs, Robert

    2000-01-01

    The development of polymer composite cryogenic tanks is a critical step in creating the next generation of launch vehicles. Future reusable launch vehicles need to minimize the gross liftoff weight (GLOW). This weight reduction is possible due to the large reduction in weight that composite materials can provide over current aluminum technology. In addition to composite technology, adhesively bonded joints potentially have several benefits over mechanically fastened joints, such as weight savings and cryogenic fluid containment. Adhesively bonded joints may be used in several areas of these cryogenic tanks, such as in lobe-to-lobe joints (in a multi-lobe concept), skirt-to-tank joint, strut-to-tank joint, and for attaching stringers and ring frames. The bonds, and the tanks themselves, must be able to withstand liquid cryogenic fuel temperatures that they contain. However, the use of adhesively bonded composite joints at liquid oxygen and hydrogen temperatures is largely unknown and must be characterized. Lockheed Martin Space Systems Company, Michoud Operations performed coupon-level tests to determine effects of material selection, cure process parameters, substrate surface preparation, and other factors on the strength of these composite joints at cryogenic temperatures. This led to the selection of a material and process that would be suitable for a cryogenic tank. KEY WORDS: Composites, Adhesive Bonding, Cryogenics

  11. Durability properties for adhesively bonded structural aerospace applications

    This paper reports on the importance of good bond durability of adhesively joined aerospace components which has been recognized for many years. Military and civilian aircraft are exposed to harsh environments in addition to severe thermal and stress cycles during their service lives. Moisture is responsible for the majority of bond failures in the field. The presence of surface contaminants (e.g., fluoride, silicones) and the non-neutral pH of poor rinse water are common causes of adhesion problems in production environments. Honeycomb panels, stringer skins, doubler plates and core cowl assemblies are bonded joint structures that are subject to environmental- or contaminant-induced debonding. The identification and characterization of the causes of such bond failures leads to improved production quality, yield and cost reduction

  12. Reliability Analysis of Adhesive Bonded Scarf Joints

    Kimiaeifar, Amin; Toft, Henrik Stensgaard; Lund, Erik;

    2012-01-01

    element analysis (FEA). For the reliability analysis a design equation is considered which is related to a deterministic code-based design equation where reliability is secured by partial safety factors together with characteristic values for the material properties and loads. The failure criteria are...... the FEA model, and a sensitivity analysis on the influence of various geometrical parameters and material properties on the maximum stress is conducted. Because the yield behavior of many polymeric structural adhesives is dependent on both deviatoric and hydrostatic stress components, different ratios...

  13. Robust Adhesive Precision Bonding in Automated Assembly Cells

    Müller, Tobias; Haag, Sebastian; Bastuck, Thomas; Gisler, Thomas; Moser, Hansruedi; Uusimaa, Petteri; Axt, Christoph; Brecher, Christian

    2014-01-01

    The assembly of optical components goes along with highest requirements regarding assembly precision. Laser products have become an integral part of many industrial, medical, and consumer applications and their relevance will increase significantly in the years to come. Still economic challenges remain. Assembly costs are driven by the demanding requirements regarding alignment and adhesive bonding. Especially challenging in precision bonding are the interdependencies between alignment and bo...

  14. The Influences of Overlap Length, Bond Line Thickness and Pretreatmant on the Mechanical Properties of Adhesives: Focussing on Bonding Glass

    Vervloed, J.; Kwakernaak, A.; Poulis, H.

    2008-01-01

    This paper focuses on the influences of overlap length, bond line thickness and pretreatment on the mechanical properties of adhesive bonds. In order to determine the bond strength, lap shear tests were performed. The researched adhesives are a 2 component epoxy and MS polymer. The smallest overlap length of the epoxy adhesive results in the highest maximum bond stress. However, there is nosignificant difference in maximum bond stresses due to different overlap lengths of the MS polymer. When...

  15. Direct observation of catch bonds involving cell-adhesion molecules

    Marshall, Bryan T.; Long, Mian; Piper, James W.; Yago, Tadayuki; McEver, Rodger P.; Zhu, Cheng

    2003-05-01

    Bonds between adhesion molecules are often mechanically stressed. A striking example is the tensile force applied to selectin-ligand bonds, which mediate the tethering and rolling of flowing leukocytes on vascular surfaces. It has been suggested that force could either shorten bond lifetimes, because work done by the force could lower the energy barrier between the bound and free states (`slip'), or prolong bond lifetimes by deforming the molecules such that they lock more tightly (`catch'). Whereas slip bonds have been widely observed, catch bonds have not been demonstrated experimentally. Here, using atomic force microscopy and flow-chamber experiments, we show that increasing force first prolonged and then shortened the lifetimes of P-selectin complexes with P-selectin glycoprotein ligand-1, revealing both catch and slip bond behaviour. Transitions between catch and slip bonds might explain why leukocyte rolling on selectins first increases and then decreases as wall shear stress increases. This dual response to force provides a mechanism for regulating cell adhesion under conditions of variable mechanical stress.

  16. Nanoindentation mapping of a wood-adhesive bond

    Konnerth, J.; Valla, A.; Gindl, W.

    2007-08-01

    A mapping experiment of a wood phenol-resorcinol-formaldehyde adhesive bond was performed by means of grid nanoindentation. The variability of the modulus of elasticity and the hardness was evaluated for an area of 17 μm by 90 μm. Overall, the modulus of elasticity of the adhesive was clearly lower than the modulus of wood cell walls, whereas the hardness of the adhesive was slightly higher compared to cell walls. A very slight trend of decreasing modulus of elasticity was found with increasing distance from the immediate bond line. However, the trend was superimposed by a high variability of the modulus of elasticity in dependence on the position in the wood cell wall. The unexpectedly high variation of the modulus between 12 and 24 GPa may be explained by the interaction between the helical orientation of the cellulose microfibrils in the S2 layer of the wood cell wall and the geometry of the three-sided Berkovich type indenter pyramid used. Corresponding to the very slight decrease in modulus with increasing distance from the bond line, a similar but clearer trend was found for hardness. Both trends of changing mechanical properties of wood cell walls with varying distance from the bond line are attributed to effects of adhesive penetration into the wood cell wall.

  17. Failure strength prediction for adhesively bonded single lap joints

    Rahman, Niat Mahmud

    For adhesively bonded joint, failure strength depends on many factors such as material properties (both adhesive and adherend), specimen geometries, test environments, surface preparation procedures, etc. Failure occurs inside constitutive materials or along joint interfaces. Based on location, adhesively bonded failure mode can be classified as adhesive failure mode, cohesive failure mode and adherend failure mode. Failure mode directly affects the failure strength of joint. For last eight decades, researchers have developed analytical, empirical or semi-empirical methods capable of predicting failure strength for adhesively bonded joints generating either cohesive failure or adherend failure. Applicability of most of the methods is limited to particular cases. In this research, different failure modes for single lap joints (SLJs) were generated experimentally using epoxy based paste adhesive. Based on experimental data and analytical study, simplified failure prediction methods were developed for each failure mode. For adhesive failure mode, it is observed that peel stress distributions concur along interface near crack initiation points. All SLJs for this test endured consistent surface treatments. Geometric parameters of the joints were varied to study their effect on failure strength. Peel stress distributions were calculated using finite analysis (FEA). Based on peel stress distribution near crack initiation point, a failure model is proposed. Numerous analytical, empirical and semi-empirical models are available for predicting failure strengths of SLJs generating cohesive failures. However, most of the methods in the literature failed to capture failure behavior of SLJs having thickness of adhesive layer as variable. Cohesive failure mode was generated experimentally using aluminum as adherend and epoxy adhesive considering thickness of adhesive layers as variable within SLJs. Comparative study was performed among various methods. It was observed that

  18. A comparison of shear bond strength of orthodontic brackets bonded with four different orthodontic adhesives

    Sharma, Sudhir; Tandon, Pradeep; Nagar, Amit; Singh, Gyan P; Singh, Alka; Chugh, Vinay K

    2014-01-01

    Objectives: The objective of this study is to compare the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets bonded with four different orthodontic adhesives. Materials and Methods: Eighty newly extracted premolars were bonded to 0.022 SS brackets (Ormco, Scafati, Italy) and equally divided into four groups based on adhesive used: (1) Rely-a-Bond (self-cure adhesive, Reliance Orthodontic Product, Inc., Illinois, USA), (2) Transbond XT (light-cure adhesive, 3M Unitek, CA, USA), (3) Transbond Plus (sixth generation self-etch primer, 3M Unitek, CA, USA) with Transbond XT (4) Xeno V (seventh generation self-etch primer, Dentsply, Konstanz, Germany) with Xeno Ortho (light-cure adhesive, Dentsply, Konstanz, Germany) adhesive. Brackets were debonded with a universal testing machine (Model No. 3382 Instron Corp., Canton, Mass, USA). The adhesive remnant index (ARI) was recordedIn addition, the conditioned enamel surfaces were observed under a scanning electron microscope (SEM). Results: Transbond XT (15.49 MPa) attained the highest bond strength. Self-etching adhesives (Xeno V, 13.51 MPa; Transbond Plus, 11.57 MPa) showed clinically acceptable SBS values and almost clean enamel surface after debonding. The analysis of variance (F = 11.85, P < 0.0001) and Chi-square (χ2 = 18.16, P < 0.05) tests revealed significant differences among groups. The ARI score of 3 (i.e., All adhesives left on the tooth) to be the most prevalent in Transbond XT (40%), followed by Rely-a-Bond (30%), Transbond Plus with Transbond XT (15%), and Xeno V with Xeno Ortho (10%). Under SEM, enamel surfaces after debonding of the brackets appeared porous when an acid-etching process was performed on the surfaces of Rely-a-Bond and Transbond XT, whereas with self-etching primers enamel presented smooth and almost clean surfaces (Transbond Plus and Xeno V group). Conclusion: All adhesives yielded SBS values higher than the recommended bond strength (5.9-7–8 MPa), Seventh generation

  19. Evaluation of bond strength of different adhesive systems: Shear and Microtensile Bond Strength Test

    GALLUSI, G.; GALEANO, P.; LIBONATI, A.; GIUCA, M.R.; CAMPANELLA, V.

    2010-01-01

    SUMMARY Objectives. Aim of this work is the in vitro bond strength evaluation of three bonding agents comparing the results of two kinds of test, Microtensile Bond Strength Test and a Shear Bond Strength Test. Bond strength tests have been used to test both direct and indirect restorative techniques to investigate if methods could give different results. Methods 72 human third molars have been collected and stored in physiological solution. Three kinds of test were conducted: 1- SB, 2- “Slice” preparation μTBS1, 3- “Stick” preparation μTBS2. We tested three different adhesive systems (Groups 1-2-3 n=24), two restorative techniques (subgroup A–B n=12). The tested adhesives were: Optibond FL (OFL) (Group 1), Optibond Solo Plus (OSP) (Group 2), Optibond Solo Plus Self-Etch (OSSE) (Group 3). For all tests was used a universal load machine Instron Machine. Results. Best values were found for Optibond FL with mean values of 45–50 MPa. Optibond Solo Plus resulted in values very similar and in some cases almost identical to FL. Optibond Solo Self Etch showed poorer adhesion in both direct and indirect restorative techniques. The parametric and non parametric statistical variance analysis pointed out the absence of significant differences between OFL and OSP, and demonstrated a significant difference for OSSE adhesive. Significance. The results confirm that a total etch two-step adhesive is the best compromise between easiness and effectiveness. PMID:23285371

  20. Failure in a composite resin-dentin adhesive bond

    Composites are drawing more and more attention as preferred materials for teeth restoration. The success of teeth restoration has been generally limited by the Composite Resin-Dentin bond strength. A testing device has been developped to allow a satisfactory testing method for evaluating bonding strength in tension and shear, which led to reproducible results. A comparaison between different bond systems has shown no significant difference in the tensile and the shear strength as well as in the fracture behavior. Moreover, results showed difference between tensile and shear strength, when considering one same bond system. Failure mode examination turned out to be, either cohesive (composite rupture), or adhesive (interface rupture) or both (mixed rupture). (orig.)

  1. Adhesive Characterization and Progressive Damage Analysis of Bonded Composite Joints

    Girolamo, Donato; Davila, Carlos G.; Leone, Frank A.; Lin, Shih-Yung

    2014-01-01

    The results of an experimental/numerical campaign aimed to develop progressive damage analysis (PDA) tools for predicting the strength of a composite bonded joint under tensile loads are presented. The PDA is based on continuum damage mechanics (CDM) to account for intralaminar damage, and cohesive laws to account for interlaminar and adhesive damage. The adhesive response is characterized using standard fracture specimens and digital image correlation (DIC). The displacement fields measured by DIC are used to calculate the J-integrals, from which the associated cohesive laws of the structural adhesive can be derived. A finite element model of a sandwich conventional splice joint (CSJ) under tensile loads was developed. The simulations indicate that the model is capable of predicting the interactions of damage modes that lead to the failure of the joint.

  2. Propagation of Iamb waves in adhesively bonded multilayered media

    ZHANG Haiyan; XIE Yuanxia; LIU Zhenqing

    2003-01-01

    The effect of introducing attenuation on Lamb wave dispersion curves is studied in this paper. Attenuation is introduced to a three-layered composite plate by an adhesive bond layer with viscous behavior. No changes are required to the transfer matrix formulation for the propagation of elastic waves. By introduction of a complex wavenumber, the model can be used to the propagation of attenuative Lamb waves. Numerical examples for a three-layered aluminium-epoxy-aluminium plate show that attenuation values of each mode in plates are related not only to attenuation, but also to the thickness of the bonded layer, which is in agreement with practical situations.

  3. Adhesive bone bonding prospects for lithium disilicate ceramic implants

    Vennila Thirugnanam, Sakthi Kumar

    Temporomandibular Joint (TMJ) implants articulating mandible with temporal bone in humans have a very high failure rate. Metallic TMJ implants available in the medical market are not osseointegrated, but bond only by mechanical interlocking using screws which may fail, mandating a second surgery for removal. Stress concentration around fixture screws leads to aseptic loosening or fracture of the bone. It has been proposed that this problem can be overcome by using an all-ceramic TMJ implant bonded to bone with dental adhesives. Structural ceramics are promising materials with an excellent track record in the field of dentis.

  4. Statistical failure analysis of adhesive resin cement bonded dental ceramics

    Wang, Yaou; Katsube, Noriko; Seghi, Robert R.; Rokhlin, Stanislav I.

    2007-01-01

    The goal of this work is to quantitatively examine the effect of adhesive resin cement on the probability of crack initiation from the internal surface of ceramic dental restorations. The possible crack bridging mechanism and residual stress effect of the resin cement on the ceramic surface are examined. Based on the fracture-mechanics-based failure probability model, we predict the failure probability of glass-ceramic disks bonded to simulated dentin subjected to indentation loads. The theor...

  5. Structural Health Monitoring of Adhesively Bonded Composite Joints

    Habib, Fady

    In recent years, many aerospace organizations have researched and implemented composite materials to achieve better fuel efficiency as well as reduced maintenance cost. In addition to the use of composites, manufacturers are investigating the use of adhesive bonded joints and composite patch bonded repairs to extend the life of their in-service aircraft. Adhesive joints are superior to traditional mechanical fasteners as they reduce stress concentration zones and overall part count. However, the integrity of an adhesive joint is difficult to inspect. Inspection of adhesive joints may be carried out using interrogation technology such as Structural Health Monitoring (SHM). This thesis focuses on the evaluation of Acoustic-Ultrasonic (AU) SHM technique for the detection of crack and disbond growth. In addition to AU, Capacitance Disbond Detection Technique (CDDT) and the Surface Mountable Crack Detection System (SMCDS) were evaluated for the detection disbonds. Results of the AU system demonstrated that AU technology may be used to detect and quantify crack and disbond growth. It was also found that SMCDS and CDDT both complement each other, as SMCDS identified the location of disbond while CDDT quantify disbond.

  6. Deformation and fracture of particulate epoxy in adhesive bonds

    Chai, H. [Tel-Aviv Univ. (Israel). Dept. of Mechanics

    1994-12-31

    The effect of bond thickness, t, on the fracture behavior of two epoxy adhesives toughened by a wide range of particle size, distribution and hardness was evaluated using DCB type test specimens. Video recording and scanning electron microscopy were used to study the damage evolution and the post-fracture morphology in the bond. The stress-strain behavior in shear was determined for a limited number of bond thicknesses using the napkin ring test specimen. Similarly to previous findings on homogeneous polymeric adhesives, G{sub IIC} and G{sub IIIC} coincided irrespective of t. Moreover, the opening and the shearing fracture energies converged to a common value when t was decreased to the micrometer range. New trends were found, however, when t approached the reinforcement size. A predominant feature of the crack propagation in this case was coalescence of voids that originated from particles ahead of the crack tip. The relief of hydrostatic stress caused by this damage is believed to be responsible for the alteration of the mode I fracture behavior as compared to homogeneous adhesives. The stiffness of the reinforcement particles played an important rule on the fracture in shear.

  7. Deformation and fracture of particulate epoxy in adhesive bonds

    Chai, H. (Tel-Aviv Univ. (Israel). Dept. of Mechanics, Materials and Structures)

    1995-01-01

    The effect of bond thickness, t, on the mode I, mode II and mode III fracture energies of two epoxy adhesives toughened by a wide range of particle size, distribution and hardness was evaluated using DCB type test specimens. A high-magnification video recording and scanning electron microscopy were used to study the damage evolution and the post-fracture morphology in the bond. The stress-strain behavior in shear was determined for a limited number of bond thicknesses using the napkin ring test specimen. Similarly to previous findings on homogeneous polymeric adhesives, G[sub IIC] and G[sub IIIC] coincided irrespective of t. Moreover, all three fracture energies converged to a single value when t was decreased to the micrometer range. New trends were found, however, when t approached the size of the reinforcement. A predominant feature of the crack propagation in this case was coalescence of voids that originated from particles ahead of the crack tip. The relief of hydrostatic stress caused by this damage is believed to be responsible for the alteration of the mode I fracture behavior as compared to homogeneous adhesives. The stiffness of the reinforcement particles played an important role in the fracture in shear.

  8. Methods for Using Durable Adhesively Bonded Joints for Sandwich Structures

    Smeltzer, Stanley S., III (Inventor); Lundgren, Eric C. (Inventor)

    2016-01-01

    Systems, methods, and apparatus for increasing durability of adhesively bonded joints in a sandwich structure. Such systems, methods, and apparatus includes an first face sheet and an second face sheet as well as an insert structure, the insert structure having a first insert face sheet, a second insert face sheet, and an insert core material. In addition, sandwich core material is arranged between the first face sheet and the second face sheet. A primary bondline may be coupled to the face sheet(s) and the splice. Further, systems, methods, and apparatus of the present disclosure advantageously reduce the load, provide a redundant path, reduce structural fatigue, and/or increase fatigue life.

  9. Evaluation of Adhesive Bonding Quality by Acoustic Emission

    Prediction of fatigue life and monitoring of fracture process for adhesively bonded CFRP composites joint have been investigated by analysis of acoustic emission signals during the fatigue and tension tests. During fatigue test, generated acoustic emission is related to stored elastic strain energy. By results of monitoring of AE event rate, fatigue process could be divided into two regions, and boundaries of two regions, fatigue cycles of the initiation of fast crack growth, were 70-80% of fatigue life even though the fatigue life were highly scattered from specimen to specimen. The result shows the possibility of predicting catastrophic failure by acoustic emission monitoring

  10. Torsional Stiffness Verification of an Adhesively Bonded Joint

    Annicchiarico, A.; Caputo, F.; De Angelis, G.; Frascà, F.; Lamanna, G.

    2010-06-01

    In the present work numerical-experimental analysis for the characterization of a structural adhesive has been performed. The numerical analysis has been carried out through the finite element method by using, for the phases pre / post processing were used commercial programs while for the phase of numerical solution the Abaqus code was used. The experimental analyses were carried out at laboratories of C.R.F. S.C.p.A. by using of a standard quasi static testing machine. Later numerical analysis was performed comparing the torsional stiffness of a vehicle in which the welded connection between the pavilion and the flank has been substituted by bonded one. This comparison has allowed to demonstrate the ability of the bonded joint discussed to provide mechanical performances comparable with those of a welded joint widely used in the automotive industry.

  11. Characterization and Development of General Material Models for use in Modeling Structures Bonded with Ductile Adhesives

    Cassino, Christopher

    2005-01-01

    Structural adhesives are materials that are capable of bearing significant loads in shear, and sometimes tension, over a range of strains and strain rates. Adhesively bonded structures can dissipate large amounts of mechanical energy and can be lighter and more efficient than many bolted or vibration welded parts. The largest barrier to using structural adhesives in more applications is the many challenges engineers are presented with when designing and analyzing adhesively bonded structures....

  12. Microtensile bond strength of different adhesive systems in dentin irradiated with Er:YAG laser

    The objective this study was to evaluate in vitro the bond strength of two etch-and-rise and one self-etching adhesive system after dentin irradiation with Er:YAG (erbium: yttrium aluminum garnet) laser using microtensile test. The results revealed that the groups treated with laser Er:YAG presented less tensile bond strength, independently to the adhesive system used. The prompt L-pop adhesive presented less microtensile bond strength compared to the other adhesives evaluated. There was no difference between single bond and excite groups. The adhesive failures were predominant in all the experimental groups. The Er:YAG laser influenced negatively bond strength values of adhesive systems tested in dental substrate

  13. Bonding of adhesives to Er:YAG laser-treated dentin

    Koliniotou-Koumpia, Eugenia; Kouros, Pantelis; Zafiriadis, Lazaros; Koumpia, Effimia; Dionysopoulos, Pavlos; Karagiannis, Vassilis

    2012-01-01

    Objective: The shear bond strength of adhesives applied to dentin was investigated after irradiation with an erbium-doped yttrium aluminum garnet (Er:YAG) laser. Methods: Superficial and deep dentin specimens from human molars were treated either with carbide bur or an Er:YAG laser. Two etch and rinse adhesives (Single Bond and XP Bond) and two self-etch adhesives (Prompt L-Pop and Xeno III) were employed to bond the composite. Shear bond strength (SBS) was determined after storage in water f...

  14. Efficacy of microtensile versus microshear bond testing for evaluation of bond strength of dental adhesive systems to enamel

    A.A. El Zohairy; M.H. Saber; A.I. Abdalla; A.J. Feilzer

    2010-01-01

    Objective The aim of the study was to evaluate the efficacy of the microtensile bond test (μTBS) and the microshear bond test (μSBS) in ranking four dental adhesives according to bond strength to enamel and identify the modes of failure involved. Materials and methods Forty-four caries-free human mo

  15. Bond strength of different adhesives to normal and caries-affected dentins

    XUAN Wei; HOU Ben-xiang; L(U) Yalin

    2010-01-01

    Background Currently, several systems of dentin substrate-reacting adhesives are available for use in the restorative treatment against caries. However, the bond effectiveness and property of different adhesive systems to caries-affected dentin are not fully understood. The objective of this study was to evaluate the bond strength of different adhesives to both normal dentin (ND) and caries-affected dentin (CAD) and to analyze the dentin/adhesive interracial characteristics.Methods Twenty eight extracted human molars with coronal medium carious lesions were randomly assigned to four groups according to adhesives used. ND and CAD were bonded with etch-and-rinse adhesive Adper~(TM) Single Bond 2 (SB2) or self-etching adhesives Clearfil SE Bond (CSE), Clearfil S~3 Bond (CS3), iBond GI (IB). Rectangular sticks of resin-dentin bonded interfaces 0.9 mm~2 were obtained. The specimens were subjected to microtensile bond strength (μTBS) testing at a crosshead speed of 1 mm/min. Mean μTBS was statistically analyzed with analysis of variance (ANOVA) and Student-Newman-Keuls tests. Interfacial morphologies were analyzed by Scanning Electron Microscopy (SEM).Results Etch-and-rinse adhesive Adper~(TM) Single Bond 2 yielded high bond strength when applied to both normal and caries-affected dentin. The two-step self-etching adhesive Clearfil SE Bond generated the highest bond strength to ND among all adhesives tested but a significantly reduced strength when applied to CAD. For the one-step self-etching adhesives, Clearfil S~3 Bond and iBond GI, the bond strength was relatively low regardless of the dentin type. SEM interfacial analysis revealed that hybrid layers were thicker with poorer resin tag formation and less resin-filled lateral branches in the CAD than in the ND for all the adhesives tested.Conclusion The etch-and-rinse adhesive performed more effectively to caries-affected dentin than the self-etching adhesives.

  16. Acoustic wave interaction with a laminated transversely isotropic spherical shell with imperfect bonding

    Hasheminejad, Seyyed M.; Maleki, M. [Iran University of Science and Technology, Acoustics Research Laboratory, Department of Mechanical Engineering, Narmak, Tehran (Iran)

    2009-02-15

    An exact analysis is carried out to study interaction of a time-harmonic plane-progressive sound field with a multi-layered elastic hollow sphere made of spherically isotropic materials with interlaminar bonding imperfections. A modal state equation with variable coefficients is set up in terms of appropriate displacement and stress functions and their spherical harmonics, ultimately leading to calculation of a global transfer matrix. A linear spring model is adopted to describe the interlaminar adhesive bonding whose effects are incorporated into the global transfer matrix by introduction of proper interfacial transfer matrices. The solution is first used to correlate the perturbation in the material elastic constants of an evacuated and water submerged steel (isotropic) spherical shell to the sensitivity of resonances appearing in the backscattered amplitude spectrum. The backscattering form function, in addition to the acoustic radiation force acting on selected transversely isotropic spherical shells with distinct degrees of material anisotropy, is subsequently calculated and discussed. An illustrative numerical example is given for a multi-layered hollow sphere with two distinct interlaminar interface conditions (i.e., perfectly and imperfectly bonded layers). Limiting cases are considered and fair agreements with solutions available in the literature are established. (orig.)

  17. Polymerization contraction stress in dentin adhesives bonded to dentin and enamel

    M. Hashimoto; A.J. de Gee; A.J. Feilzer

    2008-01-01

    Objective In a previous study on of polymerization contraction stress determinations of adhesives bonded to dentin a continuous decline of stress was observed after the adhesives had been light-cured. The decline was ascribed to stress relief caused by diffusion into the adhesive layer of water and/

  18. Factors affecting the bond strength of self-etch adhesives: A meta-analysis of literature

    P Pranau Vanajasan

    2011-01-01

    Conclusions: Our analysis has showed that two-step self-etch adhesive system showed a superior in vitro performance in comparison to one-step self-etch system. Nevertheless, certain factors such as dentin origin, site and area of bonding affect the bond strength of adhesives.

  19. Shear bond strength of metallic and ceramic brackets using color change adhesives

    Aisha de Souza Gomes Stumpf

    2013-04-01

    Full Text Available OBJECTIVE: To determine the shear bond strength of orthodontic brackets using color change adhesives that are supposed to aid in removing excess of bonding material and compare them to a traditional adhesive. METHODS: Ninety metallic and ninety ceramic brackets were bonded to bovine incisors using two color change adhesives and a regular one. A tensile stress was applied by a universal testing machine. The teeth were observed in a microscope after debonding in order to determine the Adhesive Remnant Index (ARI. RESULTS: The statistical analysis (ANOVA, Tukey, and Kruskall-Wallis tests demonstrated that the mean bond strength presented no difference when metallic and ceramic brackets were compared but the bond resistance values were significantly different for the three adhesives used. The most common ARI outcome was the entire adhesive remaining on the enamel. CONCLUSIONS: The bond strength was similar for metallic and ceramic brackets when the same adhesive system was used. ARI scores demonstrated that bonding with these adhesives is safe even when ceramic brackets were used. On the other hand, bond strength was too low for orthodontic purposes when Ortho Lite Cure was used.

  20. Post-bleaching application of an antioxidant on dentin bond strength of three dental adhesives

    Maryam Khoroushi

    2012-01-01

    Conclusions: The findings suggest that bond strength of resin to bleached dentin may be affected with the adhesive system. Reduced SBS to bleached dentin can be amended by the use of SA as an antioxidizing agent. However, the amount of reversed bond strength subsequent to applying antioxidant might be related to the kind of dental adhesive.

  1. Bonding of self-adhesive resin cements to enamel using different surface treatments: bond strength and etching pattern evaluations.

    Lin, Jie; Shinya, Akikazu; Gomi, Harunori; Shinya, Akiyoshi

    2010-08-01

    This study evaluated the shear bond strengths and etching patterns of seven self-adhesive resin cements to human enamel specimens which were subjected to one of the following surface treatments: (1) Polishing with #600 polishing paper; (2) Phosphoric acid; (3) G-Bond one-step adhesive; or (4) Phosphoric acid and G-Bond. After surface treatment, the human incisor specimens were bonded to a resin composite using a self-adhesive resin cement [Maxcem (MA), RelyX Unicem (UN), Breeze (BR), BisCem (BI), seT (SE), Clearfil SA Luting (CL)] or a conventional resin cement [ResiCem (RE)]. Representative morphology formed with self-adhesive resin cements showed areas of etched enamel intermingled with areas of featureless enamel. In conclusion, etching efficacy influenced the bonding effectiveness of self-adhesive resin cements to unground enamel, and that a combined use of phosphoric acid and G-Bond for pretreatment of human enamel surfaces improved the bond strength of self-adhesive resin cements. PMID:20668359

  2. Effect of hot-humid exposure on static strength of adhesive-bonded aluminum alloys

    Rui Zheng

    2015-09-01

    Full Text Available The effect of hot-humid exposure (i.e., 40 °C and 98% R.H. on the quasi-static strength of the adhesive-bonded aluminum alloys was studied. Test results show that the hot-humid exposure leads to the significant decrease in the joint strength and the change of the failure mode from a mixed cohesive and adhesive failure with cohesive failure being dominant to adhesive failure being dominant. Careful analyses of the results reveal that the physical bond is likely responsible for the bond adhesion between L adhesive and aluminum substrates. The reduction in joint strength and the change of the failure mode resulted from the degradation in bond adhesion, which was primarily attributed to the corrosion of aluminum substrate. In addition, the elevated temperature exposure significantly accelerated the corrosion reaction of aluminum, which accelerated the degradation in joint strength.

  3. Characterization of mode 1 and mixed-mode failure of adhesive bonds between composite adherends

    Mall, S.; Johnson, W. S.

    1985-01-01

    A combined experimental and analytical investigation of an adhesively bonded composite joint was conducted to characterize both the static and fatigue beyond growth mechanism under mode 1 and mixed-mode 1 and 2 loadings. Two bonded systems were studied: graphite/epoxy adherends bonded with EC 3445 and FM-300 adhesives. For each bonded system, two specimen types were tested: a double-cantilever-beam specimen for mode 1 loading and a cracked-lapshear specimen for mixed-mode 1 and 2 loading. In all specimens tested, failure occurred in the form of debond growth. Debonding always occurred in a cohesive manner with EC 3445 adhesive. The FM-300 adhesive debonded in a cohesive manner under mixed-mode 1 and 2 loading, but in a cohesive, adhesive, or combined cohesive and adhesive manner under mode 1 loading. Total strain-energy release rate appeared to be the driving parameter for debond growth under static and fatigue loadings.

  4. Characterization of mode I and mixed-mode failure of adhesive bonds between composite adherends

    Mall, S.; Johnson, W. S.

    1986-01-01

    A combined experimental and analytical investigation of an adhesively bonded composite joint was conducted to characterize both the static and fatigue beyond growth mechanism under mode 1 and mixed-mode 1 and 2 loadings. Two bonded systems were studied: graphite/epoxy adherends bonded with EC 3445 and FM-300 adhesives. For each bonded system, two specimen types were tested: a double-cantilever-beam specimen for mode 1 loading and a cracked-lapshear specimen for mixed-mode 1 and 2 loading. In all specimens tested, failure occurred in the form of debond growth. Debonding always occurred in a cohesive manner with EC 3445 adhesive. The FM-300 adhesive debonded in a cohesive manner under mixed-mode 1 and 2 loading, but in a cohesive, adhesive, or combined cohesive and adhesive manner under mode 1 loading. Total strain-energy release rate appeared to be the driving parameter for debond growth under static and fatigue loadings.

  5. On structural health monitoring of aircraft adhesively bonded repairs

    Pavlopoulou, Sofia

    The recent interest in life extension of ageing aircraft and the need to address the repair challenges in the new age composite ones, led to the investigation of new repair methodologies such as adhesively bonded repair patches. The present thesis focuses on structural health monitoring aspects of the repairs, evaluating their performance with guided ultrasonic waves aiming to develop a monitoring strategy which would eliminate unscheduled maintenance and unnecessary inspection costs. To address the complex nature of the wave propagation phenomena, a finite element based model identified the existing challenges by exploring the interaction of the excitation waves with different levels of damage. The damage sensitivity of the first anti-symmetric mode was numerically investigated. An external bonded patch and a scarf repair, were further tested in static and dynamic loadings, and their performance was monitored with Lamb waves, excited by surface-bonded piezoelectric transducers.. The response was processed by means of advanced pattern recognition and data dimension reduction techniques such as novelty detection and principal component analysis. An optimisation of these tools enabled an accurate damage detection under complex conditions. The phenomena of mode isolation and precise arrival time determination under a noisy environment and the problem of inadequate training data were investigated and solved through appropriate transducer arrangements and advanced signal processing respectively. The applicability of the established techniques was demonstrated on an aluminium repaired helicopter tail stabilizer. Each case study utilised alternative non-destructive techniques for validation such as 3D digital image correlation, X-ray radiography and thermography. Finally a feature selection strategy was developed through the analysis of the instantaneous properties of guided waves for damage detection purposes..

  6. Acoustic resonance scattering from a multilayered cylindrical shell with imperfect bonding.

    Rajabi, M; Hasheminejad, Seyyed M

    2009-12-01

    The method of wave function expansion is adopted to study the three dimensional scattering of a time-harmonic plane progressive sound field obliquely incident upon a multi-layered hollow cylinder with interlaminar bonding imperfection. For the generality of solution, each layer is assumed to be cylindrically orthotropic. An approximate laminate model in the context of the modal state equations with variable coefficients along with the classical T-matrix solution technique is set up for each layer to solve for the unknown modal scattering and transmission coefficients. A linear spring model is used to describe the interlaminar adhesive bonding whose effects are incorporated into the global transfer matrix by introduction of proper interfacial transfer matrices. Following the classic acoustic resonance scattering theory (RST), the scattered field and response to surface waves are determined by constructing the partial waves and obtaining the non-resonance (backgrounds) and resonance components. The solution is first used to investigate the effect of interlayer imperfection of an air-filled and water submerged bilaminate aluminium cylindrical shell on the resonances associated with various modes of wave propagation (i.e., symmetric/asymmetric Lamb waves, fluid-borne A-type waves, Rayleigh and Whispering Gallery waves) appearing in the backscattered spectrum, according to their polarization and state of stress. An illustrative numerical example is also given for a multi-layered (five-layered) cylindrical shell for which the stiffness of the adhesive interlayers is artificially varied. The sensitivity of resonance frequencies associated with higher mode numbers to the stiffness coefficients is demonstrated to be a good measure of the bonding strength. Limiting cases are considered and fair agreements with solutions available in the literature are established. PMID:19586650

  7. Development of improved polypropylene adhesive bonding by abrasion and atmospheric plasma surface modifications

    Encinas, N.; Abenojar, J.; Martínez, M A

    2012-01-01

    The present work deals with the problematic adhesive bonding of substrates with low surface energy. Different approaches have been explored with the aim of creating adequate adhesive joints based on polyolefinic substrate and polyurethane adhesive. The selected material under study was polypropylene (PP) as adherend, and a commercial Sikaflex®-252 polyurethane one component based structural adhesive (PU) as joint fluid. Among the diverse pre-treatments typically used to prepare surfaces prior...

  8. Application of radio frequency heating to wood bonding with aqueous vinyl polymer solution-isocyanate adhesives: Bond quality of four API adhesives

    The application of four aqueous vinyl polymer solution-isocyanate (API-resin) adhesives (Koyo Sangyo Co.) to wood bonding with radio frequency (RF) heating was examined. Two different types of cure systems, that is, room-temperature-cure type (Resins A and B) and heat-cure type (Resins C and D) were used. However, all of these adhesives can be used with both cure systems. Two-ply lumber (red meranti, Shorea spp.) was bonded with either RF-through heating or room-temperature curing. The bond quality of these laminates was evaluated with the compression-shear test specified in the Japan Agricultural Standard for laminated lumber

  9. Effect of tetracycline on the bond performance of etch-and-rinse adhesives to dentin

    Rodrigo Stanislawczuk; Jully Anna da Costa; Luceli Grabicoski Polli; Alessandra Reis; Alessandro Dourado Loguercio

    2011-01-01

    This study evaluated the effect of modified tetracycline on the resin-dentin bond strength (µTBS), silver nitrate uptake (SNU) and solution homogeneity (SH) of two adhesives. Dentin surfaces were treated with phosphoric acid, rinsed off and either rewetted with water (control group - CO), 2% minocycline (MI), 2% doxycyline (DO) or 2% chlorhexidine (CH). Adhesive systems (Adper Single Bond 2 and Prime Bond NT) and composite were applied and light-polymerized. Specimens were sectioned to obtain...

  10. Effectiveness of immediate bonding of etch-and-rinse adhesives to simplified ethanol-saturated dentin

    Leandro Afonso Guimarães

    2012-04-01

    Full Text Available This study examined the immediate bond strength of etch-and-rinse adhesives to demineralized dentin saturated with either water or absolute ethanol. The research hypothesis was that there would be no difference in bond strength to dentin between water or ethanol wet-bonding techniques. The medium dentin of 20 third molars was exposed (n = 5. The dentin surface was then acid-etched, left moist and randomly assigned to be saturated via either water wet-bonding (WBT or absolute ethanol wet-bonding (EBT. The specimens were then treated with one of the following etch-and-rinse adhesive systems: a 3-step, water-based system (Adper Scotchbond Multipurpose, or SBMP or a 2-step, ethanol/water-based system (Adper Single Bond 2, or SB. Resin composite build-ups were then incrementally constructed. After water storage for 24 h at 37°C, the tensile strength of the specimens was tested in a universal testing machine (0.5 mm/min. Data were analyzed by two-way ANOVA and Tukey's test (a = 5%. The failure modes were verified using a stereomicroscope (40'. For both adhesives, no significant difference in bond strength was observed between WBT and EBT (p > 0.05. The highest bond strength was observed for SB, regardless of the bonding technique (p < 0.05. No significant interaction between adhesives and bonding techniques was noticed (p = 0.597. There was a predominance of adhesive failures for all tested groups. The EBT and WBT displayed similar immediate bond strength means for both adhesives. The SB adhesive exhibited higher means for all conditions tested. Further investigations are needed to evaluate long-term bonding to dentin mediated by commercial etch-and-rinse adhesives using the EBT approach.

  11. Shear Bond Strengths and Morphological Evaluation of Filled and Unfilled Adhesive Interfaces to Enamel and Dentine

    Vajihesadat Mortazavi; Mohammadhosein Fathi; Ebrahim Ataei; Niloufar Khodaeian; Navid Askari

    2012-01-01

    In this laboratory study shear bond strengths of three filled and one unfilled adhesive systems to enamel and dentine were compared. Forty-eight extracted intact noncarious human mandibular molars were randomly assigned to two groups of 24 one for bonding to enamel and the other for bonding to dentine. Buccal and lingual surfaces of each tooth were randomly assigned for application of each one of filled (Prime & Bond NT (PBNT), Optibond Solo Plus (OBSP), and Clearfil SE Bond (CSEB)) and unfil...

  12. Oxide film microstructure: the link between surface preparation processes and strength/durability of adhesively bonded aluminum. Final report

    Hsia, K. Jimmy; Pearlstein, Arne J.; Scheeline, Alexander; Shang, Jian Ku

    2000-11-30

    Strength and durability of adhesive bonding of aluminum alloys structures are intrinsically determined by the surface microstructures and interfacial failure micromechanisms. The current project presents a multidisciplinary approach to addressing critical issues controlling the strength and durability of adhesive bonds of aluminum alloys. Three main thrust areas have been pursued: surface treatment technology development to achieve desirable surface microstructures; relationship between surface structure and properties of adhesive bonds; and failure mechanisms of adhesively bonded components.

  13. Microtensile bond strength of restorative composite bonded with self-adhesive resin cements to enamel and dentin

    Mohammed Al-Saleh

    2013-04-01

    Full Text Available PURPOSE: To determine the microtensile bond strength (µTBS of composite restorations when bonded with self-adhesive resin-cements. METHODS: Thirty caries-free extracted molars were sterilized, and divided into 5 equal groups according to adhesive used: SBMP (Scotch-Bond-Multipurpose, total-etch 3-step adhesive, 3M/ESPE, PAN (PanaviaF-2.0, resin-cement with self-etch primer, Kuraray, RXU (RelyX-Unicem, self-adhesive resin-cement, 3M/ESPE, BRZ (Breeze, self-adhesive resin-cement, Pentron and MON (Monocem, self-adhesive resin-cement, Shofu. Each group was divided into 2 subgroups (dentin or enamel. Bonding agents, used according to manufacturers’ directions, or a thin layer of resin cement was applied onto teeth flat surfaces. Six mm-thick Filtek-Z250 (3M/ESPE composite build up was made in three increments. Teeth were sectioned to obtain rectangular specimens which were subjected to tensile force until failure. Specimens were subjected to 1,000 thermo-cycles between 5oC-55°C. Means and standard deviation (SD were calculated and statistically-analyzed with ANOVA and Tukey’s t-test. Specimens’ failure modes were reported. RESULTS: SBMP showed the highest µTBS results with enamel (24.6(6.1 MPa, PAN showed high µTBS with enamel (12.1(3.9MPa and dentin (11.6(4.7MPa compared to the other self-adhesive cements. Failure modes were adhesive and mixed for self-adhesive resin-cements. MON subgroups and BRZ enamel subgroup underwent premature failure. CONCLUSION: self-adhesive resin-cements showed low µTBS compared to SBMP.

  14. Eroded dentin does not jeopardize the bond strength of adhesive restorative materials

    Janaina Barros Cruz

    2012-08-01

    Full Text Available This in vitro study evaluated the bond strength of adhesive restorative materials to sound and eroded dentin. Thirty-six bovine incisors were embedded in acrylic resin and ground to obtain flat buccal dentin surfaces. Specimens were randomly allocated in 2 groups: sound dentin (immersion in artificial saliva and eroded dentin (pH cycling model - 3× / cola drink for 7 days. Specimens were then reassigned according to restorative material: glass ionomer cement (KetacTM Molar Easy Mix, resin-modified glass ionomer cement (VitremerTM or adhesive system with resin composite (Adper Single Bond 2 + Filtek Z250. Polyethylene tubes with an internal diameter of 0.76 mm were placed over the dentin and filled with the material. The microshear bond test was performed after 24 h of water storage at 37ºC. The failure mode was evaluated using a stereomicroscope (400×. Bond strength data were analyzed with two-way ANOVA and Tukey's post hoc tests (α = 0.05. Eroded dentin showed bond strength values similar to those for sound dentin for all materials. The adhesive system showed the highest bond strength values, regardless of the substrate (p < 0.0001. For all groups, the adhesive/mixed failure prevailed. In conclusion, adhesive materials may be used in eroded dentin without jeopardizing the bonding quality. It is preferable to use an etch-and-rinse adhesive system because it shows the highest bond strength values compared with the glass ionomer cements tested.

  15. An Ultrasonic Technique to Determine the Residual Strength of Adhesive Bonds

    Achenbach, J. D.; Tang, Z.

    1999-01-01

    In this work, ultrasonic techniques to nondestructively evaluate adhesive bond degradation have been studied. The key to the present approach is the introduction of an external factor which pulls the adhesive bond in the nonlinear range, simultaneously with the application of an ultrasonic technique. With the aid of an external static tensile loading, a superimposed longitudinal wave has.been used to obtain the slopes of the stress-strain curve of an adhesive bond at a series of load levels. The critical load, at which a reduction of the slope is detected by the superimposed longitudinal wave, is an indication of the onset of nonlinear behavior of the adhesive bond, and therefore of bond degradation. This approach has been applied to the detection of adhesive bond degradation induced by cyclic fatigue loading. Analogously to the longitudinal wave case, a superimposed shear wave has been used to obtain the effective shear modulus of adhesive layers at different shear load levels. The onset of the nonlinear behavior of an adhesive bond under shear loading has been detected by the use of a superimposed shear wave. Experiments show that a longitudinal wave can also detect the nonlinear behavior when an adhesive bond is subjected to shear loading. An optimal combination of ultrasonic testing and mechanical loading methods for the detection of degradation related nonlinear behavior of adhesive bonds has been discussed. For the purpose of a practical application, an ultrasonic technique that uses a temperature increase as an alternative to static loading has also been investigated. A general strain-temperature correspondence principle that relates a mechanical strain to a temperature has been presented. Explicit strain-temperature correspondence relations for both the tension and shear cases have been derived. An important parameter which quantifies the relation between the wave velocity and temperature has been defined. This parameter, which is indicative of adhesive

  16. Comparative study to evaluate shear bond strength of RMGIC to composite resin using different adhesive systems

    Manoj G Chandak

    2012-01-01

    Full Text Available Aim: The aim of the study is to compare and evaluate the role of new dental adhesives to bond composite to the resinmodified glass inomer cement (RMGIC. Materials and Methods: Thirty specimens were prepared on acrylic blocks, with wells prepared in it by drilling holes, to retain the RMGIC. The specimens were randomly divided into three groups of ten specimens each. In Group a thin layer of selfetch adhesive (3M ESPE was applied between the RMGIC and the composite resin FILTEK P60 (3M SPE. In Group II, total etch adhesive (Adeper Scotch bond 2, 3M ESPE was applied, and in Group III, there was no application of any adhesive between RMGIC and the composite resin. After curing all the specimens, the shear bond strength was measured using an Instron universal testing machine. Results: The results were drawn and tabulated using ANOVA-fishers and Dunnet D statistical tests.The maximum shear bond strength values were recorded in Group I specimens with self-etch adhesive showing a mean value of 2.74 when compared to the Group II adhesive (Total etch showing a mean shear strength of value 1.89, where no adhesive was used, showed a minimum mean shear bond strength of 1.42. There was a great and significant difference between Group I and Group II (P value 0.05 whereas, both Group I and Group II showed a vast and significant difference from Group III (P value = 0-001. Conclusion: Hence, this present study concludes that application of self-etch adhesive (3M ESPE, U.S.A in between RMGIC and composite resin increases the shear bond strength between RMGIC and the resin composites, as compared to the total-etch type adhesive (Adeper Scotch bond 2,3M ESPE, U.S.A as well as without application of the adhesive agent.

  17. Development of nanosilica bonded monetite cement from egg shells

    This work represents further effort from our group in developing monetite based calcium phosphate cements (CPC). These cements start with a calcium phosphate powder (MW-CPC) that is manufactured using microwave irradiation. Due to the robustness of the cement production process, we report that the starting materials can be derived from egg shells, a waste product from the poultry industry. The CPC were prepared with MW-CPC and aqueous setting solution. Results showed that the CPC hardened after mixing powdered cement with water for about 12.5 ± 1 min. The compressive strength after 24 h of incubation was approximately 8.45 ± 1.29 MPa. In addition, adding colloidal nanosilica to CPC can accelerate the cement hardening (10 ± 1 min) process by about 2.5 min and improve compressive strength (20.16 ± 4.39 MPa), which is more than double the original strength. The interaction between nanosilica and CPC was monitored using an environmental scanning electron microscope (ESEM). While hardening, nanosilica can bond to the CPC crystal network for stabilization. The physical and biological studies performed on both cements suggest that they can potentially be used in orthopedics. - Highlights: • Cement raw powder is derived from egg shells. • A microwave assisted system is used for preparing monetite bone cement. • Colloidal silica is used to reinforce cement

  18. Development of nanosilica bonded monetite cement from egg shells

    Zhou, Huan, E-mail: huanzhou@cczu.edu.cn [Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, Jiangsu (China); Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Luchini, Timothy J.F.; Boroujeni, Nariman Mansouri [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Agarwal, Anand K.; Goel, Vijay K. [Department of Bioengineering, The University of Toledo, Toledo, OH (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Division of Dentistry, The University of Toledo, Toledo, OH (United States)

    2015-05-01

    This work represents further effort from our group in developing monetite based calcium phosphate cements (CPC). These cements start with a calcium phosphate powder (MW-CPC) that is manufactured using microwave irradiation. Due to the robustness of the cement production process, we report that the starting materials can be derived from egg shells, a waste product from the poultry industry. The CPC were prepared with MW-CPC and aqueous setting solution. Results showed that the CPC hardened after mixing powdered cement with water for about 12.5 ± 1 min. The compressive strength after 24 h of incubation was approximately 8.45 ± 1.29 MPa. In addition, adding colloidal nanosilica to CPC can accelerate the cement hardening (10 ± 1 min) process by about 2.5 min and improve compressive strength (20.16 ± 4.39 MPa), which is more than double the original strength. The interaction between nanosilica and CPC was monitored using an environmental scanning electron microscope (ESEM). While hardening, nanosilica can bond to the CPC crystal network for stabilization. The physical and biological studies performed on both cements suggest that they can potentially be used in orthopedics. - Highlights: • Cement raw powder is derived from egg shells. • A microwave assisted system is used for preparing monetite bone cement. • Colloidal silica is used to reinforce cement.

  19. Interaction morphology and bond strength of nanofilled simplified-step adhesives to acid etched dentin

    Vinicius DI HIPÓLITO; Reis, André Figueiredo; Mitra, Sumita B.; de Goes, Mario Fernando

    2012-01-01

    Objective: To evaluate the effect of nanofillers incorporated into adhesives on the microtensile bond strength (μ-TBS) and interfacial micromorphology to dentin. Methods: The occlusal enamel of 5 human molars was removed and each tooth sectioned into four quarters. The exposed dentin was treated with one of the following adhesives: Adper Single Bond (SB-unfilled), OptiBond Solo Plus (OS-barium aluminoborosilicate, 400nm Ø), Prime & Bond NT (NT-colloidal silica, 7–40 nm Ø) and Adper Single Bon...

  20. Biomaterial based novel polyurethane adhesives for wood to wood and metal to metal bonding

    Mitesh Ramanlal Patel

    2009-01-01

    Full Text Available Polyurethane adhesives made from synthetic chemicals are non-biodegradable, costly and difficult to find raw materials from local market. To avoid solid pollution problem, cost effectiveness and easy availability of raw materials, biomaterials based polyurethane adhesives are used in current industrial interest. Direct use of castor oil in polyurethane adhesive gives limited hardness. Modification on active sites of castor oil to utilize double bond of unsaturated fatty acid and carboxyl group yields new modified or activated polyols, which can be utilized for polyurethane adhesive formulation. In view of this, we have synthesized polyurethane adhesives from polyester polyols, castor oil based polyols and epoxy based polyols with Isocyanate adducts based on castor oil and trimethylolpropane. To study the effects of polyurethane adhesive strength (i.e. lap shear strength on wood-to-wood and metal-to-metal bonding through various types of polyols, cross-linking density, isocyanate adducts and also to compare adhesive strength between wood to wood and metal to metal surface. These polyols and polyurethanes were characterized through GPC, NMR and IR-spectroscopy, gel and surface drying time. Thermal stability of PU adhesives was determined under the effect of cross-linking density (NCO/OH ratio. The NCO/OH ratio (1.5 was optimized for adhesives as the higher NCO/OH ratio (2.0 increasing cross-linking density and decreases adhesion. Lower NCO/OH ratio (1.0 provideslow cross-linking density and low strength of adhesives.

  1. Post-bleaching application of an antioxidant on dentin bond strength of three dental adhesives

    Maryam Khoroushi; Tahereh Saneie

    2012-01-01

    Background: Antioxidizing agents have recently been suggested to compensate decreased bond strength of resin materials to bleached tooth tissues. This study compared the shear bond strength (SBS) of three different adhesives on bleached dentin immediately after bleaching, bleached/delayed for 1 week, and bleached/applied antioxidizing agent. Materials and Methods: The dentinal surfaces of 132 intact extracted molars were prepared and divided into 12 groups. The following adhesives were in...

  2. Influence of fluoride-containing adhesives and bleaching agents on enamel bond strength

    Vanessa Cavalli; Priscila Cristiane Suzy Liporoni; Marcos Augusto do Rego; Sandrine Bittencourt Berger; Marcelo Giannini

    2012-01-01

    This study evaluated the influence of fluoride-containing carbamide peroxide (CP) bleaching agents and adhesive systems on bonded enamel interfaces that are part of the dynamic pH cycling and thermal cycling models. The buccal surfaces of 60 bovine incisors were restored with a composite resin and bonded with three- and two-step, etch-and-rinse, fluoride-containing adhesives, Optibond FL (FL) and Optibond Solo Plus (SP), respectively. Restored teeth were subjected to thermal cycling to age th...

  3. Nondestructive strength evaluation of adhesive-bonded single-lap joints by signal processing method

    Application of bonding by adhesives can be found in many industries, particularly in advanced technological domains such as the aeronautical and space industries, automobile manufacture, and electronics. Periodic inspection with conventional ultrasonic NDE techniques is capable of indicating the presence and possible location of crack. Continuous ultrasonic attenuation monitoring has potential to supply information. This study used adhesive-bonded single-lap joints specimen to evaluate such possibility by ultrasonic signal processing method

  4. Lamb Wave Interaction with Adhesively Bonded Stiffeners and Disbonds Using 3D Vibrometry

    Ryan Marks; Alastair Clarke; Carol Featherston; Christophe Paget; Rhys Pullin

    2016-01-01

    There are many advantages to adhesively bonding stiffeners onto aircraft structures rather than using traditional mechanical fastening methods. However there is a lack of confidence of the structural integrity of adhesively bonded joints over time. Acousto-ultrasonic Lamb waves have shown great potential in structural health monitoring applications in both metallic and composite structures. This paper presents an experimental investigation of the use of acousto-ultrasonic Lamb waves for the m...

  5. BONDING OF MINIATURE PARTS WITH ADHESIVES AND VISION BASED PROCEDURE INSPECTION

    Wang Xiaodong; Jürgen Hesselbach

    2004-01-01

    Bonding with adhesives is an important technique for building up hybrid microsystems.Some adhesives are tested with capillary dispensing system for microassembly,and volume of droplets less than 10 nl with good repeatability can be acquired.1-part UV curing adhesive hardens rapidly and is suitable for bonding of transparent microparts.Light-activated adhesive starts the curing process in an adjustable short period of time after the radiation of visible light,and thus suits bonding of non-transparent microparts.A method is proposed for bonding the guides of a miniature linear motor being developed by collaborate research center 516 (SFB516) in Germany.With the method high assembly accuracy in the vertical direction can be guaranteed.By making small grooves on the stator for containing adhesive,the deterioration of the accuracy due to the thickness of adhesive layer can be avoided.The criteria on deciding the size of the groove are given and analyzed.Vision based inspection method is introduced for automatic assembly of the guides.The dispensing volume and position of dispensed adhesive droplets can be detected for ensuring the bonding quality.

  6. Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin

    Cécile Bernard

    2015-01-01

    Full Text Available The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL and a two-steps/self-etch adhesive system (Optibond XTR were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR. All specimens were submitted to thermocycling ageing (10000 cycles. The specimens were sectioned in 1 mm2 sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL.

  7. Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin.

    Bernard, Cécile; Villat, Cyril; Abouelleil, Hazem; Gustin, Marie-Paule; Grosgogeat, Brigitte

    2015-01-01

    The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL) and a two-steps/self-etch adhesive system (Optibond XTR) were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR). All specimens were submitted to thermocycling ageing (10000 cycles). The specimens were sectioned in 1 mm(2) sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR) adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL). PMID:26783528

  8. Bond strength evaluation in adhesive joints using NDE and DIC methods

    Poudel, Anish

    Adhesive bonding of graphite epoxy composite laminates to itself or traditional metal alloys in modern aerospace and aircraft structural applications offers an excellent opportunity to use the most efficient and intelligent combination of materials available thus providing an attractive package for efficient structural designs. However, one of the major issues of adhesive bonding is the occasional formation of interfacial defects such as kissing or weak bonds in the bondline interface. Also, there are shortcomings of existing non-destructive evaluation (NDE) methods to non-destructively detect/characterize these interfacial defects and reliably predicting the bond shear strength. As a result, adhesive bonding technology is still not solely implemented in primary structures of an aircraft. Therefore, there is a greater demand for a novel NDE tool that can meet the existing aerospace requirement for adhesive bondline characterization. This research implemented a novel Acoustography ultrasonic imaging and digital image correlation (DIC) technique to detect and characterize interfacial defects in the bondline and determine bond shear strength in adhesively bonded composite-metal joints. Adhesively bonded Carbon Fiber Reinforced Plastic (CFRP) laminate and 2024-T3 Aluminum single lap shear panels subjected to various implanted kissing/weak bond defects were the primary focus of this study. Kissing/weak bonds were prepared by controlled surface contamination in the composite bonding surface and also by improperly mixing the adhesive constituent. SEM analyses were also conducted to understand the surface morphology of substrates and their interaction with the contaminants. Morphological changes were observed in the microscopic scale and the chemical analysis confirmed the stability of the contaminant at or very close to the interface. In addition, it was also demonstrated that contaminants migrated during the curing of the adhesive from CFRP substrate which caused a

  9. Effect of glutaraldehyde and ferric sulfate on shear bond strength of adhesives to primary dentin

    Prabhakar A

    2008-12-01

    Full Text Available Aim: The present study was undertaken to evaluate the effect of alternative pulpotomy agents such as glutaraldehyde and ferric sulfate on the shear bond strength of self-etch adhesive systems to dentin of primary teeth. Materials and Methods: Eighty human primary molar teeth were sectioned in a mesiodistal direction and divided into experimental and control groups. Lingual dentin specimens in experimental groups were treated with glutaraldehyde and ferric sulfate. Buccal surfaces soaked in water served as control group. Each group was then divided into two groups based on the adhesive system used: Clearfil SE Bond and Adper Prompt L-Pop. A teflon mold was used to build the composite (Filtek Z-250 cylinders on the dentinal surface of all the specimens. Shear bond strength was tested for all the specimens with an Instron Universal Testing Machine. The failure mode analysis was performed with a Scanning Electron Microscope (SEM. Results: The results revealed that glutaraldehyde and ferric sulfate significantly reduced the shear bond strength of the tested adhesive systems to primary dentin. Clearfil SE Bond showed much higher shear bond strength than Adper Prompt L Pop to primary dentin. SEM analysis revealed a predominant cohesive failure mode for both adhesive systems. Conclusion: This study revealed that the pulpotomy medicaments glutaraldehyde and ferric sulfate adversely affected the bonding of self-etch adhesive systems to primary dentin.

  10. Bond strength comparison of color-change adhesives for orthodontic bonding using a self-etching primer

    Frey GN; Bussa HI; Powers JM; Ontiveros JC; English JD; Ekhlassi S; Colville CD; Ellis RK

    2011-01-01

    Sara Ekhlassi, Jeryl D English, Joe C Ontiveros, John M Powers, Harry I Bussa, Gary N Frey, Clark D Colville, Randy K EllisHouston Department of Orthodontics, The University of Texas Dental Branch, Houston, TX, USABackground: The purpose of this study was to compare the shear bond strengths of two color-change adhesives with a commonly used conventional light-cure adhesive while using a self-etching primer, and to compare any changes in shear bond strengths over time.Methods: One hundred and ...

  11. Evaluation method for adhesion test results of bonded wet concrete to epoxies

    Aguiar, J. L. Barroso de

    1999-01-01

    The use of epoxies is today current in repair and bonding works of concrete structures. The raison of that is the good adhesion they present in bonding hardened concrete-hardened concrete, hardened concrete-fresh concrete and hardened concrete-metallic materials. However, the adhesion decreases when the substrate concrete is wet. The incorporation of a filler in the epoxy makes possible a good adhesion even when the concrete is wet. We did tension tests to study the influence of the type, the...

  12. Hybridization quality and bond strength of adhesive systems according to interaction with dentin

    Salvio, Luciana Andrea; Hipólito, Vinicius Di; Martins, Adriano Luis; de Goes, Mario Fernando

    2013-01-01

    Objective: To evaluate the hybridization quality and bond strength of adhesives to dentin. Materials and Methods: Ten human molars were ground to expose the dentin and then sectioned in four tooth-quarters. They were randomly divided into 5 groups according to the adhesive used: Two single-step self-etch adhesives – Adper Prompt (ADP) and Xeno III (XE), two two-step self-etching primer systems – Clearfil SE Bond (SE) and Adhe SE (ADSE), and one one-step etch-and-rinse system – Adper Single Bo...

  13. Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin

    Cécile Bernard; Cyril Villat; Hazem Abouelleil; Marie-Paule Gustin; Brigitte Grosgogeat

    2015-01-01

    The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL) and a two-steps/self-et...

  14. Effect of pre-etching enamel on fatigue of self-etch adhesive bonds

    R.L. Erickson; A.J. de Gee; A.J. Feilzer

    2008-01-01

    Objective. A previous study found that the shear bond strength (SBS) to bovine enamel for the self-etching adhesive Adper Prompt-L-Pop (PLP) was 75% of that found with the etch-and-rinse material SingleBond, while the comparative value for the shear fatigue limit (SFL) was only 58% at 10(5) load cyc

  15. Ideal, catch, and slip bonds in cadherin adhesion

    Rakshit, Sabyasachi; Zhang, Yunxiang; Manibog, Kristine; Shafraz, Omer; Sivasankar, Sanjeevi

    2012-01-01

    Classical cadherin cell-cell adhesion proteins play key morphogenetic roles during development and are essential for maintaining tissue integrity in multicellular organisms. Classical cadherins bind in two distinct conformations, X-dimer and strand-swap dimer; during cellular rearrangements, these adhesive states are exposed to mechanical stress. However, the molecular mechanisms by which cadherins resist tensile force and the pathway by which they convert between different conformations are ...

  16. System integration and demonstration of adhesive bonded high temperature aluminum alloys for aerospace structure, phase 2

    Falcone, Anthony; Laakso, John H.

    1993-01-01

    Adhesive bonding materials and processes were evaluated for assembly of future high-temperature aluminum alloy structural components such as may be used in high-speed civil transport aircraft and space launch vehicles. A number of candidate high-temperature adhesives were selected and screening tests were conducted using single lap shear specimens. The selected adhesives were then used to bond sandwich (titanium core) test specimens, adhesive toughness test specimens, and isothermally aged lap shear specimens. Moderate-to-high lap shear strengths were obtained from bonded high-temperature aluminum and silicon carbide particulate-reinforced (SiC(sub p)) aluminum specimens. Shear strengths typically exceeded 3500 to 4000 lb/in(sup 2) and flatwise tensile strengths exceeded 750 lb/in(sup 2) even at elevated temperatures (300 F) using a bismaleimide adhesive. All faceskin-to-core bonds displayed excellent tear strength. The existing production phosphoric acid anodize surface preparation process developed at Boeing was used, and gave good performance with all of the aluminum and silicon carbide particulate-reinforced aluminum alloys investigated. The results of this program support using bonded assemblies of high-temperature aluminum components in applications where bonding is often used (e.g., secondary structures and tear stoppers).

  17. Void-free wafer-level adhesive bonding utilizing modified poly (diallyl phthalate)

    Zhong, Fang; Dong, Tao; Yong, He; Yan, Su; Wang, Kaiying

    2013-12-01

    A new thermosetting polymer, modified poly (diallyl phthalate) (PDAP), is used as intermediate layer to realize a void-free wafer-level transfer bonding, in which the bonding interface contains patterned metal. Through glass-silicon bonding experiments, bonding defects are easily recognized with light microscopy. Three typical defect types are identified as: uneven flow defect, particle defect and bubble defect. The processing parameters, such as bonding pressure, pre-baking temperature, polymer thickness and coating conditions, have been optimized based on analysis of the defect formation. The optimized conditions have yielded a void-free wafer-level adhesive bonding. Then, the die shearing test indicates a good bonding strength. Additionally, the transfer bonding process is applied in SOI-silicon bonding as a practical example of MEMS fabrication.

  18. Bond strength of self-adhesive resin cements to tooth structure

    Susan Hattar; Hatamleh, Muhanad M.; Faleh Sawair; Mohammad Al-Rabab’ah

    2015-01-01

    Objectives: The aim of this study was to evaluate the strength of the bond between newly introduced self-adhesive resin cements and tooth structures (i.e., enamel and dentin). Methods: Three self-adhesive cements (SmartCem2, RelyX Unicem, seT SDI) were tested. Cylindrical-shaped cement specimens (diameter, 3 mm; height, 3 mm) were bonded to enamel and dentin. Test specimens were incubated at 37 °C for 24 h. The shear bond strength (SBS) was tested in a Zwick Roll testing machine. Results w...

  19. The Effect of Epigallocatechin Gallate on the Dentin Bond Durability of Two Self-etch Adhesives

    Zahra Khamverdi

    2015-06-01

    Full Text Available Statement of the Problem: Self-etch adhesives can activate matrix metalloprotein-ase (MMP which hydrolyzes organic matrix of demineralized dentin. Epigallocatechin gallate (EGCG, especially found in green tea, could inhibit the activation of MMP. Purpose: The aim of this study was to evaluate the effect of adding Epigallocatechin gallate (EGCG into two types of adhesives on dentin bond strength. Materials and Method: In this experimental study, 64 extracted third molars were randomly divided into 16 groups. Clearfil SE Bond and Filtek Silorane System with 0 µM, 25µM, 50µM, and 100µM concentration of 95% EGCG were used for bond-ing. Following the bonding and fabrication of beams (1±0.1 mm2 and storage in distilled water, the specimens were subjected to thermal cycles. Microtensile bond strengths of 8 groups were examined after 24 hours and others were tested after 6 months. The fracture modes of specimens were evaluated by stereomicroscope and SEM. Data were analyzed by three-way ANOVA and t-test (α = 0.05. Results: The results of the three- way ANOVA test showed that types of bonding, storage time and interactive effect of EGCG concentration and bonding influenced the bond strength of specimens significantly (p<0.05. The results of the t-test indi-cated that storage time only had significant effect on bond strength of Clearfil SE Bond with no EGCG (p= 0.017. The most common failure modes in Filtek Silorane System groups and Clearfil SE Bond groups were adhesive and mixed/cohesive, respectively. The results of SEM at different magnifications showed that most fractures have occurred in the hybrid layer. Conclusion: Although adding 100 µM volume of EGCG to Clearfil SE Bond can preserve the dentin bond, incorporation of EGCG in the silorane system, especially in high concentrations, decreases the bond strength after 6 months.

  20. Bond strength comparison of color-change adhesives for orthodontic bonding using a self-etching primer

    Frey GN

    2011-06-01

    Full Text Available Sara Ekhlassi, Jeryl D English, Joe C Ontiveros, John M Powers, Harry I Bussa, Gary N Frey, Clark D Colville, Randy K EllisHouston Department of Orthodontics, The University of Texas Dental Branch, Houston, TX, USABackground: The purpose of this study was to compare the shear bond strengths of two color-change adhesives with a commonly used conventional light-cure adhesive while using a self-etching primer, and to compare any changes in shear bond strengths over time.Methods: One hundred and eighty extracted bovine incisors were randomly divided into nine groups of 20 teeth each. The teeth were prepared with a self-etching primer (Transbond™ Plus Metal lower incisor brackets were bonded directly to each tooth with two different color-change adhesives (TransbondPlus and Grengloo™ and a control (Transbond XT. The teeth were debonded at three different time points (15 minutes, 24 hours, 1 week using an Instron at 1.0 mm/min. The teeth that were to be debonded at 24 hours and 1 week were stored in distilled water at 37°C to simulate the oral environment. The data were analyzed by two-way analysis of variance and with Fisher's protected least-significant difference multiple comparisons test at the P < 0.05 level of significance. Adhesive remnant index (ARI scores were calculated for each debonded tooth.Results: Transbond Plus at 1 week had the highest mean shear bond strength (14.7 mPa. Grengloo tested at 24 hours had the lowest mean shear bond strength (11.3 mPa. The mean shear bond strengths for the remaining seven groups had a range of 12–14.5 mPa. Grengloo had >80% samples presenting with an ARI score of 1 at all times. Interestingly, both Transbond groups had ARI scores of 3 in more than 50% of their samples.Conclusion: Time had no significant effect on the mean shear bond strength of Transbond XT, Grengloo, or Transbond Plus adhesive.Keywords: bond strength, color-change adhesives, self-etching primer, orthodontic bonding 

  1. A randomized clinical trial evaluating the success rate of ethanol wet bonding technique and two adhesives

    Vajihesadat Mortazavi; Pouran Samimi; Mojgan Rafizadeh; Shantia Kazemi

    2012-01-01

    Background : Composite resin restorations may have a short lifespan due to the degradation of resin-dentin interface. Ethanol wet bonding technique may extend the longevity of resin-dentin bond. The purpose of this one year randomized clinical trial was to compare clinical performance of two adhesives with ethanol wet bonding technique. Materials and Methods: This randomized clinical trial was performed on 36 non-carious cervical lesions in 12 patients restored with composite resin using ...

  2. Microtensile and tensile bond strength of single-bottle adhesives: a new test method.

    Abdalla, A I

    2004-04-01

    To evaluate the tensile and microtensile bond strength of five single-bottle adhesives to dentine, extracted human molar teeth were used. For each tooth dentine was exposed on the occlusal surface by cutting with an isomet saw and the remaining part was mounted in a plastic ring using dental stone. The tested adhesive materials were: Scotchbond 1, Syntac SC, One-Step, Prime & Bond 2.1 and Clearfil SE Bond. The adhesive was applied to either 1 mm(2) of dentine or a circular area with a diameter of 3.9 mm. Composite resin Clearfil AP-X was placed to the adhesives using a Teflon split mould 3.9 mm in diameter and 2.5 mm in height. Tensile and microtensile bond strengths were measured using a universal testing machine at a crosshead speed of 0.5 mm min(-1). Under tensile mode, the bond strengths were 16.7 +/- 3.5, 15.2 +/- 2.5, 11.5 +/- 3.2, 13.7 +/- 2.6, 20.9 +/- 4.2 MPa for each material. Under microtensile mode, the bond strengths were 52.5 +/- 9.5, 55.3 +/- 8.3, 40.5 +/- 5.2, 37.5 +/- 8.7, 60 +/- 6.21 MPa. Fracture pattern of bonded specimens showed 66% cohesive dentine failure in samples tested for tensile bond strength. For the microtensile test, failures were mainly adhesive at the interface between adhesive and dentine (94%). PMID:15089946

  3. Test method to assess interface adhesion in composite bonding

    Teixeira de Freitas, S.; Sinke, J.

    2015-01-01

    This paper introduces a new type of peel tests dedicated to composite bonding: Composite Peel Tests. This test is inspired on the standard floating roller peel test widely used for metal bonding. The aim of this study is to investigate the potential of the Composite Peel Test to assess interface ad

  4. Influence of Ortho Primer Morelli adhesion booster on orthodontic brackets shear bond strength

    Sabrina de Mendonça Invernici

    2012-06-01

    Full Text Available OBJECTIVE: This work aimed at assessing the bond strength (AS, the site of the flaw and the relation between them and Ortho Primer Morelli® (OPM adhesion optimizer. METHODS: Sixty test specimens, made out of bovine permanent lower incisors, were divided into three groups: TXT Primer (control, in which a conventional adhesive system was applied (primer and paste; OPM, in which TXT primer was replaced by OPM; and TXT without Primer, in which only TXT paste was used. A shear force was applied at a speed of 0,5 mm/min. Failure site was assessed by the Remaining Adhesion Index (RAI. RESULTS: Kruskal-Wallis demonstrated that OPM (8.54 ± 1.86 MPa presented a statistically higher AS (p 0.05 between TXT with or without Primer (6.42 ± 2.12 MPa. Regarding the RAI, the K test demonstrated that TXT Primer and OPM (prevailing scores 2 and 3 showed higher values (p 0.05. CONCLUSION: OPM increases AS and presents the same bond failure location if compared to a conventional adhesive system; the use of the TXT adhesive system paste only was shown to have the same AS if compared to conventional systems, except it does not allow to predict the adhesive failure site; there is no correlation between AS and bond failure location, regardless of the use of any adhesion optimizer.

  5. Influence of chlorhexidine concentration on microtensile bond strength of contemporary adhesive systems

    Edson Alves de Campos

    2009-09-01

    Full Text Available The purpose of this study was to investigate the influence of chlorhexidine (CHX concentration on the microtensile bond strength (μTBS of contemporary adhesive systems. Eighty bovine central incisors were used in this study. The facial enamel surface of the crowns was abraded with 600-grit silicon carbide paper to expose flat, mid-coronal dentin surfaces. The tested materials were Scotchbond Multipurpose (SMP, Single-Bond (SB, Clearfil SE Bond (CSEB and Clearfil Tri S Bond (CTSB. All the materials were applied according to manufacturer's instructions and followed by composite application (Z250. The teeth were randomly divided into 16 groups: for the etch-and-rinse adhesives (SMP and SB, 0.12% or 2% CHX was applied prior to or after the acid etching procedure. For the self-etch adhesives (CSEB and CTSB 0.12% or 2% CHX was applied prior to the primer. Control groups for each one of the adhesive systems were also set up. The specimens were immediately submitted to μTBS testing and the data were analyzed using Analysis of Variance and the Tukey post hoc test (alpha = .01. The failure patterns of the specimens were observed using scanning electron microscopy. The effects of 2% CHX were statistically significant (p < 0.01 for the self-etch adhesives but were not significant for the etch-and-rinse adhesive systems. Analysis of the data demonstrated no statistical difference between the etch-and-rinse adhesive systems. CHX-based cavity disinfectants in concentrations higher than 0.12% should be avoided prior to the self-etch adhesive systems evaluated in this study to diminish the possibilities of reduction in bond strength.

  6. Surface Modification of Titanium and Polyimide Sheet for Adhesive Bonding

    Akram, M.

    2015-01-01

    Major industrial sectors like automotive, aerospace and others are increasingly using polymer composites in their structural parts. Polyimide sheet and adhesives, are high performance polymers. They are widely used in various engineering applications due to their excellent thermal, mechanical and ch

  7. Embedded proteins and sacrificial bonds provide the strong adhesive properties of gastroliths.

    Thormann, Esben; Mizuno, Hiroyasu; Jansson, Kjell; Hedin, Niklas; Fernández, M Soledad; Arias, José Luis; Rutland, Mark W; Pai, Ranjith Krishna; Bergström, Lennart

    2012-07-01

    The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO(3). The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude. PMID:22653376

  8. Loss effects on adhesively-bonded multilayer ultrasonic transducers by self-heating.

    Wu, Zhengbin; Cochran, Sandy

    2010-04-01

    Multilayer ultrasonic transducers are widely being used for high power applications. In these applications, typical Langevin/Tonpilz structures without any adhesive bondings however have the disadvantage of limited bandwidth. Therefore adhesively-bonded structures are still a potential solution for this issue. In this paper, two-layer piezoelectric ceramic ultrasonic transducers with two different adhesive bondlines were investigated comparing to a single-layer transducer in terms of loss effects during operation with excitation signals sufficient to cause self-heating. The theoretical functions fitted to the measured time-temperature dependency data are compared with experimental results of different piezoelectric transducers. Theoretical analysis of loss characteristics at various surface displacements and the relationship with increasing temperature are reported. The effects of self-heating on the practical performance of multilayer ultrasonic transducers with adhesive bondlines are discussed. PMID:19942247

  9. Dry chemical pretreatment of titanium and polymers for adhesive bonding. Trockenchemische Vorbehandlung von Titan und Kunststoffen fuer das Kleben

    Krueger, G.; Hennemann, O.D. (Fraunhofer-Institut fuer Angewandte Materialforschung, Bremen (Germany))

    1993-01-01

    Titan alloys have to be pretreated to increase the adhesive bonding strength. Because of environmental reasons dry chemical pretreatment methods are preferred compared to wet chemical techniques. One successful method is a silicatisation referring to the Saco-technique. Layers generated by this method on titanium or polymer substrates lead to highly water-resistant adhesive bondings. Also adhesive joints of Ti with polymer show high bond strength when polymer and Ti are Saco treated. With a suitable optimization of the technological parameters it is possible to adhesively bond polymers also with anaerobic acrylic esters. (orig.).

  10. Lamb Wave Interaction with Adhesively Bonded Stiffeners and Disbonds Using 3D Vibrometry

    Ryan Marks

    2016-01-01

    Full Text Available There are many advantages to adhesively bonding stiffeners onto aircraft structures rather than using traditional mechanical fastening methods. However there is a lack of confidence of the structural integrity of adhesively bonded joints over time. Acousto-ultrasonic Lamb waves have shown great potential in structural health monitoring applications in both metallic and composite structures. This paper presents an experimental investigation of the use of acousto-ultrasonic Lamb waves for the monitoring of adhesively bonded joints in metallic structures using 3D scanning laser vibrometry. Two stiffened panels were manufactured, one with an intentional disbonded region. Lamb wave interaction with the healthy and disbonded stiffeners was investigated at three excitation frequencies. A windowed root-mean-squared technique was applied to quantify where Lamb wave energy was reflected, attenuated and transmitted across the structure enabling the size and shape of the defect to be visualised which was verified by traditional ultrasonic inspection techniques.

  11. Development of a rubber toughened epoxy adhesive loaded with carbon nanotubes, for aluminium – polymer bonds

    Salinas-Ruiz , Maria del Mar

    2009-01-01

    This thesis describes the formulation of a ternary thermosetting adhesive which consists of a diglycidyl ether of bisphenol-A (DGEBA) epoxy resin cured with 3,3’-diamino diphenyl sulphone (3,3’-DDS) hardener and modified through the addition of carboxyl- terminated butadiene-acrylonitrile (CTBN) rubber and multi-walled carbon nanotubes (MWCNTs). Processing implications of the novel adhesive in the film form are considered in order to manufacture bonded specimens for characteris...

  12. Effects of Different Hardeners on the Working Properties and Bonding Strength of Urea-formaldehyde Adhesives

    2003-01-01

    The addition of a hardener is necessary for the curing of urea-formaldehyde (UF) adhesives in the production of MDF and particleboard. The most commonly used hardener, ammonium chloride, however, is suspected to cause the formation of poisonous dioxin when waste boards are combusted and hence considered as a potential source of pollution. To assess the feasibility of substituting ammonium sulphate for ammonium chloride, working properties and bonding strength were measured for UF adhesives with the two ...

  13. Effect of Adhesive Cementation Strategies on the Bonding of Y-TZP to Human Dentin.

    Alves, Mll; Campos, F; Bergoli, C D; Bottino, M A; Özcan, M; Souza, Roa

    2016-01-01

    This study evaluated the effects of different adhesive strategies on the adhesion of zirconia to dentin using conventional and self-adhesive cements and their corresponding adhesive resins. The occlusal parts of human molars (N=80) were sectioned, exposing the dentin. The teeth and zirconia cylinders (N=80) (diameter=3.4 mm; height=4 mm) were randomly divided into eight groups according to the factors "surface conditioning" and "cement type" (n=10 per group). One conventional cement (CC: RelyX ARC, 3M ESPE) and one self-adhesive cement (SA: RelyX U200, 3M ESPE) and their corresponding adhesive resin (for CC, Adper Single Bond Plus; for SA, Scotchbond Universal Adhesive-SU) were applied on dentin. Zirconia specimens were conditioned either using chairside (CJ: CoJet, 30 μm, 2.5 bar, four seconds), laboratory silica coating (RC: Rocatec, 110 μm, 2.5 bar, four seconds), or universal primer (Single Bond Universal-UP). Nonconditioned groups for both cements acted as the control (C). Specimens were stored in water (37°C, 30 days) and subjected to shear bond strength (SBS) testing (1 mm/min). Data (MPa) were analyzed using two-way analysis of variance and a Tukey test (α=0.05). While surface conditioning significantly affected the SBS values (p=0.0001) (Cadhesive. Air-abrasion and the use of the universal primer improved the bond strength of zirconia to dentin compared to the control group, regardless of the type of resin cement used. PMID:26509232

  14. Micro-tensile bond strength of adhesives to pulp chamber dentin after irrigation with Ethylenediaminetetraacetic acid

    Ç Barutcigil; Arslan, H; Özcan, E; O T Harorli

    2012-01-01

    Aim: The aim of this study was to evaluate the influence of different concentrations of Ethylenediaminetetraacetic acid (EDTA) solution on adhesion, that is, the bond strength of the different adhesive systems, to the pulp chamber dentin. Materials and Methods: Recently extracted, sound, human, third molars were cut horizontally to expose the pulp horn. The roof of the pulp chamber and pulp tissue was removed. The teeth were then divided into five main groups. The teeth in each group were tre...

  15. Additional Interface Corner Toughness Data for an Adhesively-Bonded Butt Joint

    Guess, T.R.; Reedy, E.D.

    1999-04-14

    Over a period of 15 months, five sets of adhesively-bonded butt joints were fabricated and tested. This previously unreported data is used to assess the variability of measured interface corner toughness values, K{sub ac}, as well as the dependence of K{sub ac} on surface preparation. A correlation between K{sub ac} and the size of the adhesive failure zone is also noted.

  16. Influence of saliva contamination on the shear bond strength of adhesives on enamel

    Tatiana Feres Assad-Loss

    2012-04-01

    Full Text Available OBJECTIVE: To evaluate shear bond strength of 3 adhesive systems (Single Bond, TransbondTM MIP and TransbondTM XT applied on bovine enamel under saliva contamination condition. METHOD: One hundred and twenty enamel surfaces of bovine incisors were divided into 6 groups (n = 20 according to the adhesive system used (TransbondTM XT, TransbondTM MIP and Single Bond with or without saliva contamination. For each adhesive system, there were two groups defined as no contamination group (NC: 37% H3PO4 conditioning for 30 seconds and two layers of adhesive systems; saliva contamination group (SC: After the first adhesive layer application, the examined areas were contaminated with saliva. Samples were mounted appropriately for testing and stored in deionized water at 37 ºC for 7 days. Samples were then submitted to shear bond strength trials at a speed of 0.5 mm/min. The Adhesive Remnant Index (ARI was evaluated under stereomicroscopy. Two-way analysis of variance and the Tukey test were used to compare mean values (α = 0.05. RESULTS: Groups XT (NC = 26.29 ± 7.23; MIP (NC = 24.47 ± 7.52 and SB (NC = 32.36 ± 4.14 XT (SC = 19.59 ± 6.76; MIP (SC = 18.08 ± 6.39 and SB (SC = 18.18 ± 7.03 MPa. ARI 0 and 1 were the most prevalent scores in all study groups examined. CONCLUSION: Saliva contamination significantly decreased bond strength of the three adhesive systems examined (p <0.05. However, the comparison of groups with and without saliva contamination did not reveal any significant differences, and, therefore, the three systems may be considered equivalent.

  17. Molecular weight effects upon the adhesive bonding of a mussel mimetic polymer.

    Jenkins, Courtney L; Meredith, Heather J; Wilker, Jonathan J

    2013-06-12

    Characterization of marine biological adhesives are teaching us how nature makes materials and providing new ideas for synthetic systems. One of the most widely studied adhering animals is the marine mussel. This mollusk bonds to wet rocks by producing an adhesive from cross-linked proteins. Several laboratories are now making synthetic mimics of mussel adhesive proteins, with 3,4-dihydroxyphenylalanine (DOPA) or similar molecules pendant from polymer chains. In select cases, appreciable bulk bonding results, with strengths as high as commercial glues. Polymer molecular weight is amongst several parameters that need to be examined in order to both understand biomimetic adhesion as well as to maximize performance. Experiments presented here explore how the bulk adhesion of a mussel mimetic polymer varies as a function of molecular weight. Systematic structure-function studies were carried out both with and without the presence of an oxidative cross-linker. Without cross-linking, higher molecular weights generally afforded higher adhesion. When a [N(C4H9)4](IO4) cross-linker was added, adhesion peaked at molecular weights of ~50,000-65,000 g/mol. These data help to illustrate how changes to the balance of cohesion versus adhesion influence bulk bonding. Mussel adhesive plaques achieve this balance by incorporating several proteins with molecular weights ranging from 6000 to 110,000 g/mol. To mimic these varied proteins we made a blend of polymers containing a range of molecular weights. Interestingly, this blend adhered more strongly than any of the individual polymers when cross-linked with [N(C4H9)4](IO4). These results are helping us to both understand the origins of biological materials as well as design high performance polymers. PMID:23668520

  18. Multitechnique monitoring of fatigue damage in adhesively bonded composite lap-joints

    Karpenko, Oleksii; Koricho, Ermias; Khomenko, Anton; Dib, Gerges; Haq, Mahmoodul; Udpa, Lalita

    2015-03-01

    The requirement for reduced structural weight has driven the development of adhesively bonded joints. However, a major issue preventing their full acceptance is the initiation of premature failure in the form of a disbond between adherends, mainly due to fatigue, manufacturing flaws or impact damage. This work presents the integrated approach for in-situ monitoring of degradation of the adhesive bond in the GFRP composite lap-joint using ultrasonic guided waves and dynamic measurements from strategically embedded FBG sensors. Guided waves are actuated with surface mounted piezoelectric elements and mode tuning is used to provide high sensitivity to the degradation of the adhesive layer parameters. Composite lap-joints are subjected to fatigue loading, and data from piezoceramic transducers are collected at regular intervals to evaluate the progression of damage. Results demonstrate that quasi-static loading affects guided wave measurements considerably, but FBG sensors can be used to monitor the applied load levels and residual strains in the adhesive bond. The proposed technique shows promise for determining the post-damage stiffness of adhesively bonded joints.

  19. Low-frequency features of the ultrasound echo from an adhesively bonded layer-substrate structure

    WANG Xiaomin; LI Mingxuan; MAO Jie; LIAN Guoxuan

    2005-01-01

    The low-frequency features of the ultrasound reflection spectra from the structure of a single layer on a substrate bonded by a thin adhesive layer are theoretically studied; the low-frequency here means the frequency of the interrogating ultrasonic wave is less than the quart-wavelength resonance frequency of the adhesive layer. The possibility of the inversion of the thickness and the evaluation of the cohesion strength of the adhesive layer from the resonance frequency shifts of the layered system is indicated. An analytic solution to the nonlinear equation satisfied by the resonance frequency is presented by Taylor expansion method showing satisfactory agreement with the numerical results by Newton iterative method. The results indicate larger range for application than the traditional spring model for the thin adhesive layer. In a much lower frequency range the thin adhesive layer may be regarded to be a spring.

  20. Effect of cleaning methods on bond strength of self-etching adhesive to dentin

    Juliana Delatorre Bronzato

    2016-01-01

    Full Text Available Aim: The aim of this study was to investigate the influence of cleaning methods to remove zinc oxide-eugenol-based root canal sealer (Endomethasone on the bond strength of the self-etching adhesive to dentin. Materials and Methods: Twenty crowns of bovine incisors were cut to expose the pulp chamber. A zinc oxide- and eugenol-based sealer was placed for 10 min in contact with the pulp chamber dentin. Specimens were divided into four groups according to the cleaning method of dentin used: G1, no root canal sealer (control; G2, 0.9% sodium chlorite (NaCl; G3, ethanol; and G4, followed by diamond drill. After cleaning, the teeth were restored with composite resin and Clearfil SE Bond. All specimens were sectioned to produce rectangular sticks and dentin/resin interface was submitted to microtensile bond testing. The mean bond strengths were analyzed using ANOVA/Tukey (α = 0.05. Results: G3 and G4 showed bond strengths similar to the G1 (P > 0.05. A significant decrease in the bond strength in the G2 was observed (P < 0.05. G1, G3, and G4, the predominant failure mode was the mixed type. The prevalence of adhesive failure mode was verified in the G2. Conclusion: The cleaning methods affected the bond strength of the self-etching adhesive to dentin differently.

  1. Study on the structural evolution of modified phenol-formaldehyde resin adhesive for the high-temperature bonding of graphite

    A novel adhesive for carbon materials composed of phenol-formaldehyde resin, boron carbide and fumed silica, was prepared. The adhesive property of graphite joints bonded by the above adhesive treated at high-temperatures was tested. Results showed that the adhesive was found to have outstanding high-temperature bonding properties for graphite. The adhesive structure was dense and uniform even after the graphite joints were heat-treated at 1500 deg. C. Bonding strength was 17.1 MPa. The evolution of adhesive structure was investigated. The results indicated that the addition of the secondary additive, fumed silica, improved the bonding performance greatly. Borosilicate phase with better stability was formed during the heat-treatment process, and the volume shrinkage was restrained effectively, which was responsible for the satisfactory high-temperature bonding performance of graphite

  2. Laser Surface Preparation for Adhesive Bonding of Ti-6Al-4V

    Belcher, Marcus A.; List, Martina S.; Wohl, Christopher J.; Ghose, Sayata; Watson, Kent A.; Hopkins, John W.; Connell, John W.

    2010-01-01

    Adhesively bonded structures are potentially lighter in weight than mechanically fastened ones, but existing surface treatments are often considered unreliable. Two main problems in achieving reproducible and durable adhesive bonds are surface contamination and variability in standard surface preparation techniques. In this work three surface pretreatments were compared: laser etching with and without grit blasting and conventional Pasa-Jell treatment. Ti-6Al-4V surfaces were characterized by contact angle goniometry, optical microscopy, and X-ray photoelectron spectroscopy (XPS). Laser -etching was found to produce clean surfaces with precisely controlled surface topographies and PETI-5 lap shear strengths and durabilities were equivalent to those produced with Pasa-Jell.

  3. Effects of endodontic tri-antibiotic paste on bond strengths of dentin adhesives to coronal dentin

    Mirzakoucheki, Parvin; Walter, Ricardo; Khalighinejad, Navid; Jahromi, Maryam Zare; Mirsattari, Sanaz; Akbarzadeh, Navid

    2015-01-01

    Objectives The aim of this study was to evaluate the effects of tri-antibiotic paste (TAP) on microtensile bond strengths (MTBS) of dental adhesives to dentin. Materials and Methods Sixty extracted molars had their occlusal surfaces flattened to expose dentin. They were divided into two groups, i.e., control group with no dentin treatment and experimental group with dentin treatment with TAP. After 10 days, specimens were bonded using self-etch (Filtek P90 adhesive) or etch-and-rinse (Adper S...

  4. Effect of Self-etching Adhesives on the Bond Strength of Glass-Ionomer Cements.

    Zahra Jaberi Ansari

    2014-12-01

    Full Text Available Adequate bond strength between glass ionomer cements and composite resin is necessary for the success of the sandwich technique.This study assessed the micro-shear bond strength of composite resin to glass-ionomer cements (GIC using self-etch adhesives with different pH values.One hundred specimens (6×4×2 mm were made using Fuji II and Fuji II LC GICs and treated with different adhesives as follows: Group 1:Fuji II+ Adper Prompt L-Pop, Group-2: Fuji II+SE bond, Group-3: Fuji II + AdheSE, Group-4:Fuji II+ Protect bond, Group-5: Fuji II + Single bond, Group-6:Fuji II LC+ Adper Prompt LPop, Group-7: Fuji II LC+SE bond, Group-8:Fuji II LC+ AdheSE, Group-9: Fuji II LC+ Protect bond, and Group-10: Fuji II LC+ Single bond. Each group consisted of 10 specimens. A cylinder of Z100 composite resin was placed on each sample and light cured. After 24 hours of water storage (37°C, the specimens were subjected to micro-shear bond strength tests (0.5 mm/min. Data were analyzed using two-way ANOVA and Tukey's test.The mean micro-shear bond strength of groups 1-10 was 11.66±1.79, 16.50±1.85, 18.47±1.77, 13.95±1.77, 15.27±1.49, 15.14±0.90, 20.03±1.19, 17.48±3.00, 16.24±1.98 and 16.03±1.49 MPa, respectively. There were significant differences between groups 1 and 7 (P0.05. Fuji II LC showed higher bond strength than Fuji II (P<0.05.Type of self-etch adhesive had no significant effect on micro-shear bond strength of glass-ionomer to composite resin. Resin modified glass ionomer cement (RMGIC exhibited higher bond strength than the conventional GIC.

  5. Post-bleaching application of an antioxidant on dentin bond strength of three dental adhesives

    Khoroushi, Maryam; Saneie, Tahereh

    2012-01-01

    Background: Antioxidizing agents have recently been suggested to compensate decreased bond strength of resin materials to bleached tooth tissues. This study compared the shear bond strength (SBS) of three different adhesives on bleached dentin immediately after bleaching, bleached/delayed for 1 week, and bleached/applied antioxidizing agent. Materials and Methods: The dentinal surfaces of 132 intact extracted molars were prepared and divided into 12 groups. The following adhesives were investigated: Optibond FL (OFL) (three-step etch-and-rinse), Optibond Solo Plus (two-step etch-and-rinse), and Optibond all-in-one (OA) (one-step self-etch) (Kerr, Orange, USA). Unbleached dentin groups (groups 1-3) were prepared as negative controls (NC). The remainder surfaces (groups 4-12) were bleached with 20% Opalescent PF (Ultradent, USA). Specimens were bonded immediately after bleaching (groups 4-6), after 1 week (groups 7-9), or after using 10% sodium ascorbate (SA) gel (groups 10-12). Subsequent to bonding of composite resin, the samples were tested for SBS and analyzed using Kruskal-Wallis and Mann-Whitney tests (α=0.05). Results: Regarding control groups, OA showed the highest SBS among the studied adhesives (P0.05) except the of delay bonding with OA. Conclusions: The findings suggest that bond strength of resin to bleached dentin may be affected with the adhesive system. Reduced SBS to bleached dentin can be amended by the use of SA as an antioxidizing agent. However, the amount of reversed bond strength subsequent to applying antioxidant might be related to the kind of dental adhesive. PMID:22363363

  6. Effect of thermal cycling on the bond strength of self-adhesive cements to fiber posts.

    Mazzitelli, Claudia; Monticelli, Francesca; Toledano, Manuel; Ferrari, Marco; Osorio, Raquel

    2012-06-01

    The aim of this study was to assess the push-out bond strengths of self-adhesive resin cements to epoxy resin-based fiber posts after challenging by thermocycling. Thirty-six single-rooted premolars were endodontically treated, and the post-spaces were drilled to receive RelyX Fiber posts #1. Three self-adhesive resin cements (RelyX Unicem, G-Cem, and Breeze) were used for luting fiber posts. The bonded specimens were either stored for 1 month in a moist field (37°C) or submitted to thermocycling (5,000 times) prior to push-out test. The maximum force required to dislodge the post via an apical-coronal direction was recorded (megapascal). The data were statistically analyzed with two-way ANOVA and Tukey tests (p Breeze were higher than those of G-Cem. After thermocycling, the bond strength of G-Cem increased and no differences were found between groups. RelyX Unicem and Breeze bond strengths were not affected by the thermal challenge. Thermal cycling and cement type differently influence the bond strengths of self-adhesive resin cements. Self-adhesive cements can represent an option for luting fiber posts into root canal. PMID:21670983

  7. Effects of Type I Collagen Degradation on the Durability of Three Adhesive Systems in the Early Phase of Dentin Bonding

    Hu, Lin; Xiao, Yu-hong; Fang, Ming; Gao, Yu; Huang, Li; Jia, An-qi; Chen, Ji-hua

    2015-01-01

    Objective This study was designed to evaluate the effects of type I collagen degradation on the durability of three adhesive systems in the early phase of dentin bonding. Methods Bonded dentin specimens were prepared using three different types of adhesive systems. Micro-tensile bond strength and degradation of collagen were tested before, and after 1 month or 4 months of aging in artificial saliva. The relationship between micro-tensile bond strength and collagen degradation was analyzed by ...

  8. Nondestructive Characterization of Adhesive Bonds from Guided Wave Data

    Mal, A.; Lih, S-S.; Bar-Cohen, Y.

    1994-01-01

    The critical role played by interface zones in the fracture and failure of composites and other bonded materials is well known. The existing nondestructive evaluation methods are generally not capable of yielding useful quantitative information of the strength of an interface.

  9. Adhesively bonded composite reinforcements for steel structures: durability of the stress transfer

    CHATAIGNER, Sylvain; GAGNON, Arnaud; Quiertant, Marc; BENZARTI, Karim; Aubagnac, Christophe

    2012-01-01

    Nowadays, externally bonded composites are currently used for reinforced concrete structures repair or reinforcement. Such a technique allows increasing the service life of concrete bridges. In the case of steel bridges, applications of this technique are not significant. This may be due to the similarity of both materials rigidity, but also to the lack of confidence of structure owners in using structural adhesive bonding as assembly technique. In the scope of a research work led by the IFST...

  10. Shear bond strength between alumina substrate and prosthodontic resin composites with various adhesive resin systems

    AlJehani, Yousef A.; Baskaradoss, Jagan K; Geevarghese, Amrita; AlShehry, Marey A; Pekka K. Vallittu

    2015-01-01

    Background With the increase in demand for cosmetics and esthetics, resin composite restorations and all-ceramic restorations have become an important treatment alternative. Taking into consideration the large number of prosthodontic and adhesive resins currently available, the strength and durability of these materials needs to be evaluated. This laboratory study presents the shear bond strengths of a range of veneering resin composites bonded to all-ceramic core material using different adh...

  11. Shear bond strength of amalgam to dentin using different dentin adhesive systems

    Farimah Sardari

    2012-01-01

    Full Text Available Background and Aims: The aim of this in vitro study was to assess the shear bond strength of amalgam to dentin using four dentin adhesive systems.Materials and Methods: One hundred human molars were selected. After enamel removal, a dentin cylinder with 3 mm thickness was prepared. Eighty specimens were resorted with amalgam and four dentin adhesive systems as follows (n=20: group 1, Scotch Bond Multi-Purpose; group 2, One Coat Bond; group 3, PQ1; and group 4, Panavia-F. In group 5, 20 specimens were resorted with amalgam and varnish as control group. The specimens were incubated at 37°C for 24 h. The shear bond strengths were then measured by using push out method. The data were analyzed by one-way ANOVA and post hoc Duncan's tests.Results: Mean values for bond strengths of test groups were as follows: group 1=21.03±8.9, group 2=23.47±9, group 3=13.16±8.8, group 4=20.07±8.9 and group 5=14.15±8.7 MPa±SD. One-way ANOVA showed the statistically significant difference between the bond strengths of five groups (P=0.001. Post hoc Duncan's test showed significant difference between groups 1and 3 (P=0.008, groups 1 and 5 (P=0.019, groups 2 and 5 (P=0.0008, groups 4 and 5 (P=0.042, and groups 3 and 4 (P=0.018.Conclusion: Results of this study showed that the bond strength of amalgam to dentin using One Coat Bond as dentin adhesive system was higher than that observed in other dentin adhesive systems.

  12. A simple surface treatment and characterization of AA 6061 aluminum alloy surface for adhesive bonding applications

    Highlights: ► A very simple surface treatment method to achieve excellent and durable aluminum adhesive bonding. ► Our method involves simple immersion of aluminum in very dilute NaOH solution at room temperature with no involvement of strong acids or multiple procedures. ► Surface analysis via various surface characterization techniques showed morphological and chemical modifications favorable for obtaining highly durable bond strengths on the treated surface. ► Safe, economical, reproducible and simple method, easily applicable in industries. - Abstract: Structural adhesive bonding of aluminum is widely used in aircraft and automotive industries. It has been widely noted that surface preparation of aluminum surfaces prior to adhesive bonding plays a significant role in improving the strength of the adhesive bond. Surface cleanliness, surface roughness, surface wettability and surface chemistry are controlled primarily by proper surface treatment methods. In this study, we have employed a very simple technique influencing all these criteria by simply immersing aluminum substrates in a very dilute solution of sodium hydroxide (NaOH) and we have studied the effect of varying the treatment period on the adhesive bonding characteristics. A bi-component epoxy adhesive was used to join the treated surfaces and the bond strengths were evaluated via single lap shear (SLS) tests in pristine as well as degraded conditions. Surface morphology, chemistry, crystalline nature and wettability of the NaOH treated surfaces were characterized using various surface analytical tools such as scanning electron microscopy and energy dispersive X-ray analysis (SEM/EDX), optical profilometry, infrared reflection absorption spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and contact angle goniometry. Excellent adhesion characteristics with complete cohesive failure of the adhesive were encountered on the NaOH treated surfaces that are comparable to the benchmark

  13. Effect of digluconate chlorhexidine on bond strength between dental adhesive systems and dentin: A systematic review

    Dimitrios Dionysopoulos

    2016-01-01

    Full Text Available Aim: This study aimed to systematically review the literature for the effect of digluconate chlorhexidine (CHX on bond strength between dental adhesive systems and dentin of composite restorations. Materials and Methods: The electronic databases that were searched to identify manuscripts for inclusion were Medline via PubMed and Google search engine. The search strategies were computer search of the database and review of reference lists of the related articles. Search words/terms were as follows: (digluconate chlorhexidineFNx01 AND (dentinFNx01 OR adhesive systemFNx01 OR bond strengthFNx01. Results: Bond strength reduction after CHX treatments varied among the studies, ranging 0-84.9%. In most of the studies, pretreatment CHX exhibited lower bond strength reduction than the control experimental groups. Researchers who previously investigated the effect of CHX on the bond strength of dental adhesive systems on dentin have reported contrary results, which may be attributed to different experimental methods, different designs of the experiments, and different materials investigated. Conclusions: Further investigations, in particular clinical studies, would be necessary to clarify the effect of CHX on the longevity of dentin bonds.

  14. The analysis of adhesively bonded advanced composite joints using joint finite elements

    Stapleton, Scott E.

    The design and sizing of adhesively bonded joints has always been a major bottleneck in the design of composite vehicles. Dense finite element (FE) meshes are required to capture the full behavior of a joint numerically, but these dense meshes are impractical in vehicle-scale models where a course mesh is more desirable to make quick assessments and comparisons of different joint geometries. Analytical models are often helpful in sizing, but difficulties arise in coupling these models with full-vehicle FE models. Therefore, a joint FE was created which can be used within structural FE models to make quick assessments of bonded composite joints. The shape functions of the joint FE were found by solving the governing equations for a structural model for a joint. By analytically determining the shape functions of the joint FE, the complex joint behavior can be captured with very few elements. This joint FE was modified and used to consider adhesives with functionally graded material properties to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. Furthermore, proof-of-concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint. Furthermore, the capability to model non-linear adhesive constitutive behavior with large rotations was developed, and progressive failure of the adhesive was modeled by re-meshing the joint as the adhesive fails. Results predicted using the joint FE was compared with experimental results for various

  15. The Analysis of Adhesively Bonded Advanced Composite Joints Using Joint Finite Elements

    Stapleton, Scott E.; Waas, Anthony M.

    2012-01-01

    The design and sizing of adhesively bonded joints has always been a major bottleneck in the design of composite vehicles. Dense finite element (FE) meshes are required to capture the full behavior of a joint numerically, but these dense meshes are impractical in vehicle-scale models where a course mesh is more desirable to make quick assessments and comparisons of different joint geometries. Analytical models are often helpful in sizing, but difficulties arise in coupling these models with full-vehicle FE models. Therefore, a joint FE was created which can be used within structural FE models to make quick assessments of bonded composite joints. The shape functions of the joint FE were found by solving the governing equations for a structural model for a joint. By analytically determining the shape functions of the joint FE, the complex joint behavior can be captured with very few elements. This joint FE was modified and used to consider adhesives with functionally graded material properties to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. Furthermore, proof-of-concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint. Furthermore, the capability to model non-linear adhesive constitutive behavior with large rotations was developed, and progressive failure of the adhesive was modeled by re-meshing the joint as the adhesive fails. Results predicted using the joint FE was compared with experimental results for various

  16. Does the 4f-shell contribute to bonding in tetravalent lanthanide halides?

    Lanthanide tetrahalide molecules LnX4 (Ln = Ce, Pr, Tb; X = F, Cl, Br, I) have been investigated by density functional theory at the levels of the relativistic Zero Order Regular Approximation and the relativistic energy-consistent pseudopotentials, using frozen small- and medium-cores. The calculated bond lengths and vibrational frequencies are close to the experimental data. Our calculations indicate 4f shell contributions to bonding in LnX4, in particular for the early lanthanides, which show significant overlap between the Ln 4f-shell and the halogen np-shells. The 4f shells contribute to Ln-X bonding in LnX4 about one third more than in LnX3

  17. Failure criterion for adhesively bonded joints using Arcan´s experimental method

    Demetrio Jackson dos Santos

    2014-08-01

    Full Text Available Characterization of polymeric materials mechanical behavior requires some previous knowledge about their structure, which allows the choice of more appropriated models and methods. Polymeric materials, below their glass transition temperature (Tg, may be handled as perfect elastic solids, allowing the use of classic mechanics to characterize their behavior. Polymers above their Tg present a viscous contribution to mechanical behavior, which has to be taken into consideration by modeling it. Adhesively bonded joint, joining of different materials using a polymer as adhesive, adds to the mentioned requirements more parameters, such as surface roughness, adhesive thickness and different types of contributions to adhesively bonded joint strength. This work has the purpose of presenting a mechanical behavior characterization of adhesive bonded joints, concerning their average stress at rupture. A modified Arcan´s device was used to obtain the average stress at rupture under different angles or loading conditions, such as pure shear 0°, pure tensile strength 90° and combined conditions. The experimental results were applied to a theoretical model, which takes into consideration the hydrostatic contribution to the mechanical behavior, called Drucker-Prager Model, which was initially developed to characterize soils.

  18. Hydrogen Bonding in Liquid Water and in the Hydration Shell of Salts.

    Dagade, Dilip H; Barge, Seema S

    2016-03-16

    A near-IR spectral study on pure water and aqueous salt solutions is used to investigate stoichiometric concentrations of different types of hydrogen-bonded water species in liquid water and in water comprising the hydration shell of salts. Analysis of the thermodynamics of hydrogen-bond formation signifies that hydrogen-bond making and breaking processes are dominated by enthalpy with non-negligible heat capacity effects, as revealed by the temperature dependence of standard molar enthalpies of hydrogen-bond formation and from analysis of the linear enthalpy-entropy compensation effects. A generalized method is proposed for the simultaneous calculation of the spectrum of water in the hydration shell and hydration number of solutes. Resolved spectra of water in the hydration shell of different salts clearly differentiate hydrogen bonding of water in the hydration shell around cations and anions. A comparison of resolved liquid water spectra and resolved hydration-shell spectra of ions highlights that the ordering of absorption frequencies of different kinds of hydrogen-bonded water species is also preserved in the bound state with significant changes in band position, band width, and band intensity because of the polarization of water molecules in the vicinity of ions. PMID:26749515

  19. Atmospheric pressure plasma surface modification of titanium for high temperature adhesive bonding

    Akram, M.; Jansen, K.M.B.; Ernst, L.J.; Bhowmik, S.

    2011-01-01

    In this investigation surface treatment of titanium is carried out by plasma ion implantation under atmospheric pressure plasma in order to increase the adhesive bond strength. Prior to the plasma treatment, titanium surfaces were mechanically treated by sand blasting. It is observed that the contac

  20. Adhesive bond failure monitoring with triboluminescent optical fiber sensor

    Shohag, Md Abu S.; Hammel, Emily C.; Olawale, David O.; Okoli, Okenwa O.

    2016-04-01

    One of the most severe damage modes in modern wind turbines is the failure of the adhesive joints in the trailing edge of the large composite blades. The geometrical shape of the blade and current manufacturing techniques make the trailing edge of the wind turbine blade more sensitive to damage. Failure to timely detect this damage type may result in catastrophic failures, expensive system downtime, and high repair costs. A novel sensing system called the In-situ Triboluminescent Optical Fiber (ITOF) sensor has been proposed for monitoring the initiation and propagation of disbonds in composite adhesive joints. The ITOF sensor combines the triboluminescent property of ZnS:Mn with the many desirable features of optical fiber to provide in-situ and distributed damage sensing in large composite structures like the wind blades. Unlike other sensor systems, the ITOF sensor does not require a power source at the sensing location or for transmitting damage-induced signals to the hub of the wind turbine. Composite parts will be fabricated and the ITOF integrated within the bondline to provide in-situ and real time damage sensing. Samples of the fabricated composite parts with integrated ITOF will be subjected to tensile and flexural loads, and the response from the integrated sensors will be monitored and analyzed to characterize the performance of the ITOF sensor as a debonding damage monitoring system. In addition, C-scan and optical microscopy will be employed to gain greater insights into the damage propagation behavior and the signals received from the ITOF sensors.

  1. Effect of new adhesion promoter and mechanical interlocking on bonding strength in metal-polymer composites

    Schuberth, A.; Göring, M.; Lindner, T.; Töberling, G.; Puschmann, M.; Riedel, F.; Scharf, I.; Schreiter, K.; Spange, S.; Lampke, T.

    2016-03-01

    There are various opportunities to improve the adhesion between polymer and metal in metal-plastic composites. The addition of a bonding agent which reacts with both joining components at the interfaces of the composite can enhance the bonding strength. An alternative method for the adjustment of interfaces in metal-plastic composites is the specific surface structuring of the joining partners in order to exploit the mechanical interlock effect. In this study the potential of using an adhesion promoter based on twin polymerization for metal-plastic composites in combination with different methods of mechanical surface treatment is evaluated by using the tensile shear test. It is shown that the new adhesion promoter has a major effect when applied on smooth metal surfaces. A combination of both mechanical and chemical surface treatment of the metal part is mostly just as effective as the application of only one of these surface treatment methods.

  2. Optimisation of industrial production of low-force sensors - adhesive bonding of force-centring ball

    Maeder, T.; Jacq, C.; Blot, M.; Ryser, P.

    2016-01-01

    This work addresses the issue of attaching the force-centring part (a round ball) to the load cell of a force sensor, a piezoresistive thick-film Wheatstone bridge deposited onto a ceramic cantilever. As the current soldering process requires expensive metallisation steps for both the ball and the cantilever, and subjects the solder pads used for mounting the cantilever to an additional reflow cycle, an alternative adhesive bonding process was developed, allowing both simpler production and the use of other ball materials such as ceramic and glass. The selfcentring action of solder capillary forces was ensured by structuring the adhesive so as to form a mechanical cuvette allowing centring of the ball by gravity. The selected adhesive materials exhibited good printability and bonding, as well as surviving the subsequent soldering and cleaning process steps.

  3. COMPOSITE RESIN BOND STRENGTH TO ETCHED DENTINWITH ONE SELF PRIMING ADHESIVE

    P SAMIMI

    2002-09-01

    Full Text Available Introduction. The purpose of this study was to compare shear bond strength of composite resins to etched dentin in both dry and wet dentin surface with active and inactive application of a single-bottle adhesive resin (Single Bond, 3M Dental products. Methods. Fourthy four intact human extracted molars and premolars teeth were selected. The facial surfaces of the teeth were grounded with diamond bur to expose dentin. Then specimens were divided into four groups of 11 numbers (9 Molars and 2 Premolars. All the samples were etched with Phosphoric Acid Gel 35% and then rinsed for 10 seconds. The following stages were carried out for each group: Group I (Active-Dry: After rinsing, air drying of dentin surface for 15 seconds, active priming of adhesive resin for 15 seconds, air drying for 5 seconds, the adhesive resin layer was light cured for 10 seconds. Group III (Inactive-Dry:After rinsing, air drying of dentin surface for 15 seconds, adhesive resin was applied and air dryied for 5 seconds, the adhesive layer was light cured for 10 seconds. Group III (Active-Wet:After rinsing, removal of excess water of dentin surface with a cotton roll, active priming of adhesive resin for 15 seconds and air drying for 5 seconds, the adhesive layer was light cured for 10 seconds. Group IV (Inactive-Wet:After rinsing, removal of excess water of dentin surface with a cotton roll, the adhesive resin was applied and air dryied for 5 seconds and then cured for 10 seconds. After adhesive resin application, composite resin (Z250, 3M Dental products was applied on prepared surface with cylindrical molds (with internal diameter of 2.8mm, & height of 5mm and light-cured for 100 seconds (5x20s. The samples were then thermocycled. They were located in 6±3c water .temperature for 10 seconds and then 15 seconds in inviromental temperature, 10s in 55±3c water temperature and then were located at room temperature for 15s. This test was repeated for 100s. All of the specimens

  4. The influence of an adhesive system on shear bond strength of repaired high-copper amalgams.

    Hadavi, F; Hey, J H; Ambrose, E R; elBadrawy, H E

    1991-01-01

    The shear bond strengths of intact high-copper spherical and admixed amalgams were compared with repaired high-copper spherical and admixed amalgam specimens with and without the use of an adhesive system (Amalgambond). In the spherical group the shear bond strength of the repaired specimens was found to be 55 and 53.2% of the intact specimens without and with the use of the adhesive system. After thermocycling those percentages were 48.5 and 43. In the admixed groups those percentages were 39, 36.5, 34.5, and 35.2 respectively. It was found that the application of Amalgambond did not significantly increase the strength of the repaired amalgam. Thermocycling only had a significantly adverse effect on the repair strength in the admixed group repaired without an adhesive system. PMID:1813872

  5. Effect of Repeated Container Lid Opening on Dentin Shear Bond Strength of Two Dentin Adhesive Systems

    H. Hassanzadeh

    2008-03-01

    Full Text Available Objective: Comparing the effect of repeated opening of the container lid of two dentin adhesive systems, Prime&Bond NT (P&B NT and iBond (iB, on shear bond strength.Materials and Methods: Intact bovine lower incisors (n=60, fixed in acrylic were ran-domly divided into six groups (n=10. Groups I and II were set as control groups. P&B NT and iB were applied on the samples after five days a week, three times a day for two weeks of use in groups III and VI; and after four weeks of use in groups V and VI. The samples were evaluated by a universal testing-machine (Instron, cross-head speed 1mm/min and stereomicroscope.Results: There was no significant difference between the bond strengths in any of the three P&B NT. The mean amount of the shear bond strength for iB after 60 times of use (15.31 MPa was significantly lowerthan that at the baseline (23.51 MPa. There was no significant difference between iB at the baseline and after 30 times of use (19.26 Mpa, and also between iB after 30 times of use and after 60 times of use. All P&B NT groups showed significantly highershear bond strengths when compared with their similar iB groups in iB.Conclusion: Repeated use (60 times of the all-in-one adhesive container seems to reduce dentin shear bond strength. Therefore, containers with a lower content of the same adhe-sive or a single-dose of the adhesive are preferred.

  6. Effects of long-term repeated topical fluoride applications and adhesion promoter on shear bond strengths of orthodontic brackets

    Endo, Toshiya; Ishida, Rieko; Komatsuzaki, Akira; Sanpei, Shinya; Tanaka, Satoshi; Sekimoto, Tsuneo

    2014-01-01

    Objective: The purpose of this study was to assess the effects of long-term repeated topical application of fluoride before bonding and an adhesion promoter on the bond strength of orthodontic brackets. Materials and Methods: A total of 76 bovine incisors were collected and divided equally into four groups. In group 1, the brackets were bonded without topical fluoride application or adhesion promoter. In group 2, before bonding, the adhesion promoter was applied to nonfluoridated enamel. In group 3, the brackets were bonded without the application of the adhesion promoter to enamel, which had undergone long-term repeated topical fluoride treatments. Teeth in group 4 received the long-term repeated topical applications of fluoride, and the brackets were bonded using the adhesion promoter. All the brackets were bonded using BeautyOrtho Bond self-etching adhesive. The shear bond strength was measured and the bond failure modes were evaluated with the use of the adhesive remnant index (ARI) after debonding. Results: The mean shear bond strength was significantly lower in group 3 than in groups 1, 2, and 4, and there were no significant differences between the groups except for group 3. There were significant differences in the distribution of ARI scores between groups 2 and 3, and between groups 3 and 4. Conclusions: The adhesion promoter can recover the bond strength reduced by the long-term repeated topical applications of fluoride to the prefluoridation level and had a significantly great amount of adhesives left on either fluoridated or nonfluoridated enamel. PMID:25512720

  7. Bonding to sound vs caries-affected dentin using photo- and dual-cure adhesives.

    Say, Esra Can; Nakajima, Masatoshi; Senawongse, Pisol; Soyman, Mübin; Ozer, Füsun; Tagami, Junji

    2005-01-01

    This study aimed to evaluate the microtensile bond strength (microTBS) of photo- and dual-cure adhesives to sound and caries-affected dentin using total- and self-etch techniques. Human third molars with occlusal caries were prepared as previously described by Nakajima and others (1995). Dentin surfaces were bonded with Optibond Solo Plus (Kerr; photo-cure adhesive) or Optibond Solo Plus + Dual-cure activator (Kerr; dual-cure adhesive) with total- and self-etch technique. Clearfil AP-X (Kuraray) was used for composite buildups. Following storage in distilled water at 37 degrees C for 24 hours, the teeth were sectioned into 0.7-mm thick slices to obtain sound and caries-affected dentin slabs, then trimmed to form hour glass shapes with a 1 mm2 cross-sectional area. The specimens were subjected to microtensile testing using EZ-test (Shimadzu) at 1 mm/minute. Data were analyzed using three-way ANOVA and Student's t-Test (p<0.05). Bond strengths to sound dentin with photo- and dual-cure adhesives using total- and self-etch techniques were significantly higher than those to caries-affected dentin. Dual-cure adhesive significantly decreased bond strengths both to sound and caries-affected dentin. The total-etch technique showed no beneficial effect on caries-affected dentin compared with the self-etch technique. Scanning electron microscopic observation of the resin-dentin interfaces revealed that hybrid layers in caries-affected dentin were thicker than those observed in sound dentin with photo- and dual-cure adhesives. Resin infiltration into dentinal tubules of caries-affected dentin was hampered by the presence of mineral deposits. PMID:15765963

  8. Comparative Shear-Bond Strength of Six Dental Self-Adhesive Resin Cements to Zirconia

    Si-Eun Lee; Ji-Hyeon Bae; Jae-Won Choi; Yong-Chan Jeon; Chang-Mo Jeong; Mi-Jung Yoon; Jung-Bo Huh

    2015-01-01

    This study compared shear bond strength (SBS) of six self-adhesive resin cements (SARC) and one resin-modified glass ionomer cement (RMGIC) to zirconia before and after thermocycling. The cylinder shape (Φ 2.35 mm × 3 mm) of six SARCs (G-CEM LinkAce (GLA), Maxcem Elite (MAX), Clearfil SA Luting (CSL), PermaCem 2.0 (PM2), Rely-X U200 (RXU), Smartcem 2 (SC2)) were bonded to the top surface of the zirconia specimens with light-curing. RMGIC (Fujicem (FJC)) was bonded to the specimens with self-c...

  9. Effect of water storage on microshear bond strength of four dental adhesive systems to dentin

    Montenegro, Robinson Viegas; Carlo, Hugo Lemes; Batista, André Ulisses Dantas; Montenegro, Sheyla Christinne Lira; Farias, Ohana Rodrigues

    2015-01-01

    AIM: To evaluate the microshear bond strength of 4 dental adhesive systems after 1 year-water storage. MATERIAL AND METHODS: The sample consisted of 120 cylinders of composite, obtained from 24 bovine incisors, which were divided into four experimental groups: G1-Scotchbond Multi-Purpose, G2-Single Bond 2, G3-Clearfil SE Bond, G4-Adper Easy One and two storage times in distilled water: T0 - 24h and T1 - 1 year. A bivariate analysis was performed using the ANOVA and Tukey test (α=0.05). Result...

  10. Three-dimensional Material and Geometrical Nonlinear Analysis of Adhesively Bonded Single Lap Joint

    S. Narasimhan

    2003-04-01

    Full Text Available The paper presents 3-D viscoplastic analysis of adhesively bonded single lap joint considering material and geometric nonlinearity. Total Lagrangian formulation is used to develop a 3-D finite element for geometric nonlinear analysis. The overall geometry of the single lap joint, the loading, and the boundary conditions has been considered, both according to the ASTM testing standards and from those adopted in earlier investigations. The constitutive relations for the adhesive are developed using a pressure-dependant (modified von Mises yield function and Ramberg-Osgood idealisation for the experimental stress-strain curve. The adherends and adhesive layers are both modelled using 20-noded solid elements. However, observations have been made, in particular, on peel and shear stresses in the adhesive layer, which provide useful insight into the 3-D nature of the problem.

  11. Effect of Nanofiller Addition to an Experimental Dentin Adhesive on Microtensile Bond Strength to Human Dentin

    SH. Kasraei

    2009-06-01

    Full Text Available Objective: The purpose of the study was to evaluate the influence of adding nanofiller particles to a dentin bonding agent on resin-dentin bond strength.Materials and Methods: Fifty-four human intact premolar teeth were divided in to 6 groups of nine. The teeth were ground on occlusal surfaces and polished with 320 and then 600 grit silicon carbide papers. An experimental bonding system based on acetone/alcoholsolvent was provided with filler contents of 0.0, 0.5, 1.0, 2.5, 5.0, and 10.0 weight percent fumed silica nanofiller. After dentin surface etching, rinsing and blot drying, the experimentalbonding agents were applied to dentin surface. A composite resin was, then,bonded to the dentin on the bonding agent. The specimens were thermocycled for 500 cycles and sectioned in stick form. After two week of storage in distilled water, resin-dentin microtensile bond strength of the specimens was measured. Data were analyzed by one way ANOVA and DunnettT3 tests.Results: Bond strength to dentin was significantly affected by the filler level. Minimum and maximum resin-microtensile bond strength was in the experimental bonding agent with no filler (5.88 MPa and with filler level of 1.0 weight percent (15.15 MPa, respectively,and decreased with the increase of filler content down to 8.95 MPa for the filler level of 10.0 weight percent.Conclusion: Filler content seems to be one of the important factors influencing the bond strength of dental adhesives. Maximum dentin bond strength was obtained with 1% silanized nanofiller silica added to experimental adhesive system.

  12. On the adhesion between hydroxyl-terminated polybutadiene fuel-binder and ammonium perchlorate. Performance of bonding agents

    Hori, K.; Iwama, A.; Fukuda, T.

    1985-12-01

    A simple method to evaluate the adhesive force between solid oxidizer and polymeric fuel-binder is presented. As an illustration, hydroxyl-terminated polybutadiene (HTPB) sticks including several different bonding agents are bonded on ammonium perchlorate (AP) single crystals, and stress-strain history unitl rupture occurs is obtained by applying uniaxial tensile stress perpendicularly to the adhesion surface. Further, whether each bonding agent reacts with AP or not was analysed with pursuing infrared absorption spectra. The hypothesis that the interfacial adhesive force arises from hydrogen bonding force is proposed.

  13. Long-term bond strength of adhesive systems applied to etched and deproteinized dentin

    Ninoshka Uceda-Gómez

    2007-12-01

    Full Text Available The aim of this study was to evaluate the early and 12-month bond strength of two adhesive systems (Single Bond-SB and One Step-OS applied to demineralized dentin (WH and demineralized/NaOCl-treated dentin (H. Twenty flat dentin surfaces were exposed, etched, rinsed and slightly dried. For the H groups, a solution of 10% NaOCl was applied for 60 s, rinsed (15 s and slightly dried. The adhesives were applied according to the manufacturer's instructions and composite resin crowns were incrementally constructed. After 24 h (water-37ºC, the specimens was sectioned in order to obtain resin-dentin sticks (0.8 mm². The specimens were tested in microtensile (0.5 mm/min immediately (IM or after 12 months of water storage (12M. The data (MPa were subjected to ANOVA and Tukey's test (a=0.05. Only the main factors adhesive and time were significant (p=0.004 and p=0.003, respectively. SB (42.3±9.1 showed higher bond strengths than OS (33.6±11.6. The mean bond strength for IM-group (42.5±8.7 was statistically superior to 12M (33.3±11.8. The use of 10% NaOCl, after acid etching, did not improve the immediate and the long-term resin-dentin bond strength.

  14. Influence of fluoride-containing adhesives and bleaching agents on enamel bond strength

    Vanessa Cavalli

    2012-12-01

    Full Text Available This study evaluated the influence of fluoride-containing carbamide peroxide (CP bleaching agents and adhesive systems on bonded enamel interfaces that are part of the dynamic pH cycling and thermal cycling models. The buccal surfaces of 60 bovine incisors were restored with a composite resin and bonded with three- and two-step, etch-and-rinse, fluoride-containing adhesives, Optibond FL (FL and Optibond Solo Plus (SP, respectively. Restored teeth were subjected to thermal cycling to age the interface. Both SP and FL adhesive-restored teeth were bleached (n = 10 with 10% CP (CP and 10% CP + fluoride (CPF or were left unbleached (control. Bleaching was performed for 14 days simultaneously with pH cycling, which comprised of 14 h of remineralization, 2 h of demineralization and 8 h of bleaching. The control groups (FL and SP were stored in remineralizing solution during their bleaching periods and were also subjected to carious lesion formation. Parallelepiped-shaped samples were obtained from the bonded interface for microtensile bond strength (∝TBS testing. The enamel ∝TBS of the FL and SP groups (control, not bleached were higher (p FL + CPF = FL + CP and SP > SP + CPF = SP + CP. The groups subjected to treatment with the fluoride-containing bleaching agents exhibited similar ∝TBS compared to regular bleaching agents. Bleaching agents, regardless of whether they contained fluoride, decreased enamel bond strength.

  15. Influence of fluoride-containing adhesives and bleaching agents on enamel bond strength.

    Cavalli, Vanessa; Liporoni, Priscila Cristiane Suzy; Rego, Marcos Augusto do; Berger, Sandrine Bittencourt; Giannini, Marcelo

    2012-01-01

    This study evaluated the influence of fluoride-containing carbamide peroxide (CP) bleaching agents and adhesive systems on bonded enamel interfaces that are part of the dynamic pH cycling and thermal cycling models. The buccal surfaces of 60 bovine incisors were restored with a composite resin and bonded with three- and two-step, etch-and-rinse, fluoride-containing adhesives, Optibond FL (FL) and Optibond Solo Plus (SP), respectively. Restored teeth were subjected to thermal cycling to age the interface. Both SP and FL adhesive-restored teeth were bleached (n = 10) with 10% CP (CP) and 10% CP + fluoride (CPF) or were left unbleached (control). Bleaching was performed for 14 days simultaneously with pH cycling, which comprised of 14 h of remineralization, 2 h of demineralization and 8 h of bleaching. The control groups (FL and SP) were stored in remineralizing solution during their bleaching periods and were also subjected to carious lesion formation. Parallelepiped-shaped samples were obtained from the bonded interface for microtensile bond strength (μTBS) testing. The enamel μTBS of the FL and SP groups (control, not bleached) were higher (p FL > FL + CPF = FL + CP and SP > SP + CPF = SP + CP). The groups subjected to treatment with the fluoride-containing bleaching agents exhibited similar μTBS compared to regular bleaching agents. Bleaching agents, regardless of whether they contained fluoride, decreased enamel bond strength. PMID:23184165

  16. Comparative Shear-Bond Strength of Six Dental Self-Adhesive Resin Cements to Zirconia

    Si-Eun Lee

    2015-06-01

    Full Text Available This study compared shear bond strength (SBS of six self-adhesive resin cements (SARC and one resin-modified glass ionomer cement (RMGIC to zirconia before and after thermocycling. The cylinder shape (Φ 2.35 mm × 3 mm of six SARCs (G-CEM LinkAce (GLA, Maxcem Elite (MAX, Clearfil SA Luting (CSL, PermaCem 2.0 (PM2, Rely-X U200 (RXU, Smartcem 2 (SC2 were bonded to the top surface of the zirconia specimens with light-curing. RMGIC (Fujicem (FJC was bonded to the specimens with self-curing. The shear bond strength of all cemented specimens was measured with universal testing machine. Half of the specimens were thermocycled 5000 times before shear bonding strength testing. Fractured surfaces were examined with a field-emission SEM (10,000× and analyzed by energy dispersive x-ray analysis. MAX, PM2, SC2 group without thermocycling and GLA, MAX, PM2 group with thermocycling showed adhesive failure, but GLA, CSL, RXU, FJC group without thermocycling and SLC, RXU, SC2, FJC group with thermocycling indicated cohesive failure. Within the limitation of this study, All of SARCs except MAX demonstrated higher bond strength than that of RMGIC regardless of thermocycling. Also, SARC containing MDP monomers (CSL retained better bonds than other cements.

  17. Composite shear bond strength to dry and wet enamel with three self-etch adhesives

    Shafiee F

    2006-01-01

    Full Text Available Background and Aim: The bonding mechanisms of self etching primers, based upon the simultaneous etching and priming of dentin, simplifies the bonding technique, but the efficiency of these systems is still controversial. This study compared the shear bond strength of three self etch adhesive systems in dry and wet conditions. Materials and Method: In this experimental study, 77 intact bovine lower incisors with flat 600 grit sanded enamel surface were fixed in acrylic molds and divided into 7 groups, of 11 teeth. The enamel surfaces were treated according to a special procedure as follows: Group 1: Prompt L-Pop (PLP in dry condition, Group 2: Prompt L-Pop in wet condition, Group 3: Clearfield SE Bond (CSEB in dry condition, Group 4: Clearfield SE Bond in wet condition, Group 5: iBond (iB in dry condition, Group 6: iBond in wet condition, Group 7: Margin Bond (Control in dry condition. Surfaces were air dried for ten seconds, or blot dried in wet condition. Composite resin was bonded on the enamel and built up by applying a cylindric teflon split mold (4 mm height 2mm diameter. After 24 hours storage in dionized water at room temperature, all specimens were thermocycled and shear bond test was employed by a universal testing machine (Instron with a cross-head speed of 1mm/min. The shear bond strength was recorded in MPa and data were analyzed with ANOVA and Scheffe statistical tests. P<0.05 was considered as statistically significant. The mode of failure was examined under a stereomicroscope. Results: 1- Shear bond strength of CSEB in dry condition (21.5 ± 4.8 MPa was significantly higher than PLP and iB groups (p<0.0001. 2- Shear bond strength of iB and PLP groups in dry condition (9.60 ± 2.2, 9.49 ± 3 MPa were significantly lower than CSEB and control (2.99 ± 5.1 MPa (P<0.0001. 3- There was no significant difference between PLP and iB groups in dry condition (P=1. 4- Shear bond strength of CSEB in wet condition (21.8 ± 3 MPa was

  18. Influence of dentin contamination by temporary cements on the bond strength of adhesive systems

    Josimeri Hebling

    2009-01-01

    Full Text Available Objective: The aim of this study was to assess the bond strength of adhesive systems to dentin contaminated by temporary cements with or without eugenol. Method: Flat dentin surfaces were obtained from twenty-four human third molars. With exception of the control group (n=8, the surfaces were covered with Interim Restorative Material (Caulk Dentsplay, Milford, DE, USA or Cavit (3M ESPE, St. Paul, MN, USA and kept in an oven at 37oC for seven days. After removing the cements, the adhesive systems Adper Single Bond (3M ESPE, St. Paul, MN, USA or Clearfil SE Bond (Kuraray Co. Ltd., Osaka, Japan were applied in accordance with the manufacturers’ recommendations, and then the crowns were constructed in of resin composite. The teeth were sectioned into specimens with a cross-sectional bond area of 0.81mm2, which were sub mitted to microtensile testing in a mechanical test machine at an actuator speed of 0.5mm/min. The data were analyzed by t- and ANOVA tests, complemented by Tukey tests (α=0.05. Results: For Adper Single Bond (3M ESPE, St. Paul, MN, USA, bond strength did not differ statistically (p>0.05 for all the experimental conditions. For Clearfil SE Bond (Kuraray Co. Ltd., Osaka, Japan, only the Interim Restorative Material (Caulk Dentsplay, Milford, DE, USA Group showed significantly lower bond strength (30.1±13.8 MPa in comparison with the other groups; control (38.9±13.5 MPa and Cavit (3M ESPE, St. Paul, MN, USA (42.1±11.0 MPa, which showed no significant difference between them.Conclusion: It was concluded that the previous covering of dentin with temporary cement containing eugenol had a deleterious effect on the adhesive performance of the self-etching system only.

  19. Effect of caries infiltrant application on shear bond strength of different adhesive systems to sound and demineralized enamel

    Jia, Liuhe; Stawarczyk, Bogna; Schmidlin, Patrick R; Attin, Thomas; Wiegand, Annette

    2012-01-01

    Purpose: To investigate the influence of caries infiltrant application on the shear bond strength of different adhesives on sound and demineralized enamel. Materials and Methods: Sound and artificially demineralized (14 days, acidic buffer, pH 5.0) bovine enamel specimens were treated with a caries infiltrant (Icon, DMG), three different commercial adhesives (unfilled etchand- rinse adhesive: Heliobond, Ivoclar Vivadent; filled etch-and-rinse adhesive: Optibond FL, Kerr; or self-etching adhes...

  20. Locally measuring the adhesion of InP directly bonded on sub-100 nm patterned Si

    Pantzas, K.; Le Bourhis, E.; Patriarche, G.; Troadec, D.; Beaudoin, G.; Itawi, A.; Sagnes, I.; Talneau, A.

    2016-03-01

    A nano-scale analogue to the double cantilever experiment that combines instrumented nano-indentation and atomic force microscopy is used to precisely and locally measure the adhesion of InP bonded on sub-100 nm patterned Si using oxide-free or oxide-mediated bonding. Surface-bonding energies of 0.548 and 0.628 J m-2, respectively, are reported. These energies correspond in turn to 51% and 57% of the surface bonding energy measured in unpatterned regions on the same samples, i.e. the proportion of unetched Si surface in the patterned areas. The results show that bonding on patterned surfaces can be as robust as on unpatterned surfaces, provided care is taken with the post-patterning surface preparation process and, therefore, open the path towards innovative designs that include patterns embedded in the Si guiding layer of hybrid III-V/Si photonic integrated circuits.

  1. Effects of type I collagen degradation on the durability of three adhesive systems in the early phase of dentin bonding.

    Lin Hu

    Full Text Available This study was designed to evaluate the effects of type I collagen degradation on the durability of three adhesive systems in the early phase of dentin bonding.Bonded dentin specimens were prepared using three different types of adhesive systems. Micro-tensile bond strength and degradation of collagen were tested before, and after 1 month or 4 months of aging in artificial saliva. The relationship between micro-tensile bond strength and collagen degradation was analyzed by calculating their Pearson's correlation coefficient.Aging induced time-dependent reduction in micro-tensile bond strengths for all the tested adhesive systems, although such reduction for the single-step self-etching adhesive G-Bond (GB was not statistically significant. The bond strength of the two-step self-etching primer adhesive system Clearfil SE Bond (SEB was similar to that of the two-step etch-and-rinse self-priming adhesive system Single Bond 2 (SB, and they were both significantly reduced after one or four months of aging. A negative correlation was found between the degree of collagen degradation and magnitude of micro-tensile bond strength (r = -0.65, p = 0.003. The Pearson's correlation coefficient was 0.426, indicating that 42.6% of the aging-induced reduction in bond strength can be explained by the degradation of collagen.In the early phase of dentin bonding, there was a negative correlation between the degree of collagen degradation and the magnitude of micro-tensile bond strength. The reduction of bond strength was accompanied by the degradation of collagen. These results provide evidence for the causative relationship between the degradation of collagen and the deterioration of dentin-adhesive interface.

  2. Effect of delayed insertion of composite resin on the bond strength of etch-and-rinse adhesive systems

    Edson Alves de CAMPOS; SAAD, José Roberto Cury; Sizenando Toledo PORTO NETO; Campos, Lucas Arrais; de Andrade, Marcelo Ferrarezi

    2009-01-01

    Introduction: Etch-and-rinse adhesive systems are characterized bythe dental acid etching previously to the monomer application. Thesematerials can be classified as 3-step (when primer and bond are applied separately) or 2-step (when the primer and bond functions are carried out by a single component). Objective: To determine the influence of immediate or delayed insertion of restorative material on the values of bond strength of 2-step and 3-step etch-and-rinse adhesive systems using the mic...

  3. Influence of laser etching on enamel and dentin bond strength of Silorane System Adhesive.

    Ustunkol, Ildem; Yazici, A Ruya; Gorucu, Jale; Dayangac, Berrin

    2015-02-01

    The aim of this in vitro study was to evaluate the shear bond strength (SBS) of Silorane System Adhesive to enamel and dentin surfaces that had been etched with different procedures. Ninety freshly extracted human third molars were used for the study. After the teeth were embedded with buccal surfaces facing up, they were randomly divided into two groups. In group I, specimens were polished with a 600-grit silicon carbide (SiC) paper to obtain flat exposed enamel. In group II, the overlying enamel layer was removed and exposed dentin surfaces were polished with a 600-grit SiC paper. Then, the teeth in each group were randomly divided into three subgroups according to etching procedures: etched with erbium, chromium:yttrium-scandium-gallium-garnet laser (a), etched with 35% phosphoric acid (b), and non-etched (c, control). Silorane System Adhesive was used to bond silorane restorative to both enamel and dentin. After 24-h storage in distilled water at room temperature, a SBS test was performed using a universal testing machine at a crosshead speed of 1 mm/min. The data were analyzed using two-way ANOVA and Bonferroni tests (p  0.05). The SBS of self-etch adhesive to dentin was not statistically different from enamel (p > 0.05). Phosphoric acid treatment seems the most promising surface treatment for increasing the enamel and dentin bond strength of Silorane System Adhesive. PMID:23912781

  4. Use of high and low frequency dielectric measurements in the NDE of adhesively bonded composite joints

    Pethrick, R. A.; Hayward, D.; McConnell, B. K.; Crane, R. L.

    2005-05-01

    Dielectric spectroscopy has been developed as a non-destructive technique for assessment of moisture content and structural integrity of adhesively bonded joints. Knowledge of these parameters is particularly crucial for the aerospace industry, since environmental degradation of adhesive joints presents a major limit on their utilization. High and low frequency measurements have been carried out on joints assembled from CFRP adherend, and a commercially available adhesive (AF 163-2K). The samples have been aged in deionised water at 75oC to chart the effect water ingress has on bond durability. In addition, some joints have been exposed to cryogenic temperatures to mimic the conditions joints experience whilst an aircraft is in flight. In this way it has been possible to determine the extent of degradation caused by freezing of water within the joint structure. Dielectric behaviour of the joints was studied in both the frequency and in the time domain. Frequency domain analysis allows the amount and effects of moisture ingress in the bondline to be assessed, whereas the time domain highlights the onset of joint defects with increasing exposure time. Mechanical testing of the joints has been carried out to enable correlation between changes in strength and failure mechanism due to moisture ingress, with changes in the dielectric data. In addition, dielectric studies of the neat adhesive have been undertaken, as have gravimetric and dynamic mechanical thermal analysis. These have helped reveal the effects of ageing upon the adhesive layer itself.

  5. Enhancing structural integrity of adhesive bonds through pulsed laser surface micro-machining

    Diaz, Edwin Hernandez

    2015-06-01

    Enhancing the effective peel resistance of plastically deforming adhesive joints through laser-based surface micro-machining Edwin Hernandez Diaz Inspired by adhesion examples commonly found in nature, we reached out to examine the effect of different kinds of heterogeneous surface properties that may replicate this behavior and the mechanisms at work. In order to do this, we used pulsed laser ablation on copper substrates (CuZn40) aiming to increase adhesion for bonding. A Yb-fiber laser was used for surface preparation of the substrates, which were probed with a Scanning Electron Microscope (SEM) and X-ray Photoelectron Spectroscopy (XPS). Heterogeneous surface properties were devised through the use of simplified laser micromachined patterns which may induce sequential events of crack arrest propagation, thereby having a leveraging effect on dissipation. The me- chanical performance of copper/epoxy joints with homogeneous and heterogeneous laser micromachined interfaces was then analyzed using the T-peel test. Fractured surfaces were analyzed using SEM to resolve the mechanism of failure and adhesive penetration within induced surface asperities from the treatment. Results confirm positive modifications of the surface morphology and chemistry from laser ablation that enable mechanical interlocking and cohesive failure within the adhesive layer. Remarkable improvements of apparent peel energy, bond toughness, and effective peel force were appreciated with respect to sanded substrates as control samples.

  6. Investigation of the impact of cleaning on the adhesive bond and the process implications

    EMERSON,JOHN A.; GUESS,TOMMY R.; ADKINS,CAROL L. JONES; CURRO,JOHN G.; REEDY JR.,EARL DAVID; LOPEZ,EDWIN P.; LEMKE,PAUL A.

    2000-05-01

    While surface cleaning is the most common process step in DOE manufacturing operations, the link between a successful adhesive bond and the surface clean performed before adhesion is not well understood. An innovative approach that combines computer modeling expertise, fracture mechanics understanding, and cleaning experience to address how to achieve a good adhesive bond is discussed here to develop a capability that would result in reduced cleaning development time and testing, improved bonds, improved manufacturability, and even an understanding that leads to improved aging. A simulation modeling technique, polymer reference interaction site model applied near wall (Wall PRISM), provided the capability to include contaminants on the surface. Calculations determined an approximately 8% reduction in the work of adhesion for 1% by weight of ethanol contamination on the structure of a silicone adhesive near a surface. The demonstration of repeatable coatings and quantitative analysis of the surface for deposition of controlled amounts of contamination (hexadecane and mineral oil) was based on three deposition methods. The effect of the cleaning process used on interfacial toughness was determined. The measured interfacial toughness of samples with a Brulin cleaned sandblasted aluminum surface was found to be {approximately} 15% greater than that with a TCE cleaned aluminum surface. The sensitivity of measured fracture toughness to various test conditions determined that both interfacial toughness and interface corner toughness depended strongly on surface roughness. The work of adhesion value for silicone/silicone interface was determined by a contact mechanics technique known as the JKR method. Correlation with fracture data has allowed a better understanding between interfacial fracture parameters and surface energy.

  7. Effect of service environments on adhesively bonded joints in composite structures

    Singhal, S. N.; Chamis, C. C.; Murthy, P. L. N.

    1992-01-01

    The models employed in the present computational methods for evaluating severe service-environment effects on adhesively bonded joints in composites are based on composite analyses and structural mechanics, encompassing nonlinear environmental degradation. The methods are demonstrated for the case of a butt joint with a single doubler, subjected to the environmental effects as well as static and cyclic loads. The highest joint strength is noted to be required in the case of cyclic loads and hygrothermal service environments; margins of safety for adhesive material stresses decline rapidly in such cases.

  8. Moisture distribution measurements in adhesive-bonded composites using the D (3He,p)4 He reaction

    Adhesive bonding of composite materials for many aircraft components offers a distinct advantage in weight and cost reduction compared to similar structures that have been joined by riveting. However, the long term performance of adhesive-bonded components depends on the degree and rate of moisture absorption by the adhesive in the service environment. To investigate the rate and the mechanism of water transport in adhesive-bonded composite materials, a nuclear reaction analysis method based on the D(3He,p)4He reaction is used to measure the moisture distributions. Samples of graphite/epoxy composite materials were bonded with an epoxy adhesive and isothermally conditioned in a controlled D2O environment at 70% relative humidity and 770C for various exposure times. The moisture profiles were measured along the adhesive (adhesive scan) as well as through the thickness of the bonded joint (transverse scan). The dimensions of the probing beam were 125 μm x 125 μm for the adhesive scan and 25 μ x 200 μm for the transverse scan. Absolute deuterium concentrations were determined by comparison of the proton yield from the composite/adhesive to that from reference standards. Calculations from diffusion models of water transport based on parameters determined from bulk measurement techniques are compared to the measured profile and the agreement indicates that classical Fickian diffusion describes the transport of moisture in these materials

  9. Effect of Multiple Coatings of One-step Self-etching Adhesive on Microtensile Bond Strength to Primary Dentin

    Lin Ma; Jian-feng Zhou; Jian-guo Tan; Quan Jing; Ji-zhi Zhao; Kuo Wan

    2011-01-01

    Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly divided into 2 groups with 6 teeth each. In group 1,each tooth was hemisected into two halves. One half was assigned to control subgroup 1,which was bonded with a single-step self-etching adhesive according to the manufacturer's instructions; the other half was assigned to experimental subgroup 1 in which the adhesive was applied three times before light curing. In group 2, the teeth were also hemisected into two halves. One half was assigned to control subgroup 2, which was bonded with the single-step self-etching adhesive according to the manufacturer's instructions; the other half was assigned to experimental subgroup 2 in which three layers of adhesive were applied with light curing each successive layer. Microtensile bond strength was immediately tested after specimen preparation.Results When the adhesive was applied three times before light curing, the bond strength of the experimental subgroup 1 (n=33, 57.49±11.61 MPa) was higher than that of the control subgroup 1 (n=31,49.71±11.43 MPa, P0.05).Conclusion multiple coatings of one-step self-etching adhesive can increase the immediate bond strength to primary dentin when using the technique of light-curing after applying three layers of adhesive.

  10. Effect of EDTA Conditioning and Carbodiimide Pretreatment on the Bonding Performance of All-in-One Self-Etch Adhesives

    Shipra Singh

    2015-01-01

    Full Text Available Objective. This study evaluated the effect of ethylenediaminetetraacetic acid (EDTA conditioning and carbodiimide (EDC pretreatment on the shear bond strength of two all-in-one self-etch adhesives to dentin. Methods. Flat coronal dentin surfaces were prepared on one hundred and sixty extracted human molars. Teeth were randomly divided into eight groups according to two different self-etch adhesives used [G-Bond and OptiBond-All-In-One] and four different surface pretreatments: (a adhesive applied following manufacturer’s instructions; (b dentin conditioning with 24% EDTA gel prior to application of adhesive; (c EDC pretreatment followed by application of adhesive; (d application of EDC on EDTA conditioned dentin surface followed by application of adhesive. Composite restorations were placed in all the samples. Ten samples from each group were subjected to immediate and delayed (6-month storage in artificial saliva shear bond strength evaluation. Data collected was subjected to statistical analysis using three-way ANOVA and post hoc Tukey’s test at a significance level of p<0.05.  Results and Conclusion. EDTA preconditioning as well as EDC pretreatment alone had no significant effect on the immediate and delayed bond strengths of either of the adhesives. However, EDC pretreatment on EDTA conditioned dentin surface resulted in preservation of resin-dentin bond strength of both adhesives with no significant fall over six months.

  11. Analysis of an adhesively bonded single lap joint subjected to eccentric loading

    Anyfantis, Konstantinos; Tsouvalis, N. G.

    2013-01-01

    A new experimental test is proposed, which allows the contribution of Mode I, II and III fracture modes to the failure of the adhesive layer of bonded joints aiming at achieving the realistic conditions often occurring during loading of practical joints. The main objective of this test is...... benchmarking of computational tools. The test is based on a Single Lap Joint subjected to Eccentric Loading (SLJ-EL). The basic concept that lies behind this configuration is that the applied in-plane tensile load leads the adhesive layer to develop normal stresses, in-plane and out-of-plane shear stresses......, which correspond to Mode I, II and III loading and fracture. These tests were designed so that the metal substrates do not enter plasticity and the adhesive achieves a mode mixity ratio between Mode II and Mode III not lower than 0.5. The experiments were simulated in a 3-dimensional finite element...

  12. Influence of chlorhexidine application on longitudinal adhesive bond strength in deciduous teeth

    Vicente Castelo Branco Leitune

    2011-10-01

    Full Text Available The aim of this study was to evaluate the influence of applying 2% chlorhexidine for 30 seconds after phosphoric acid conditioning of dentin on the immediate and long-term bond strengths in deciduous teeth. The occlusal enamel was removed from 40 human sound deciduous molars, which were exfoliated by natural means, and the dentin was conditioned with 37% phosphoric acid for 15 seconds and washed with running water. The specimens were divided into two groups of 20 teeth. The test group received an application of 2% chlorhexidine for 30 seconds prior to a three-step etch-and-rinse adhesive system, whereas the control group received only the adhesive system. Three cylindrical restorations were made with a composite resin for each tooth. Ten teeth in each group were submitted to a microshear bond strength test after 24 hours, while the remaining teeth were stored in distilled water at 37 °C for 6 months before testing the microshear bond strength. The test group had a higher bond strength than did the control group after 6 months of storage. No statistical differences were found when groups with the same dentin treatment were compared at different times. Short applications of chlorhexidine at low concentrations prevent hybrid layer degradation and positively affect bond strength over time.

  13. Reliability Analysis for Adhesive Bonded Composite Stepped Lap Joints Loaded in Fatigue

    Kimiaeifar, Amin; Sørensen, John Dalsgaard; Lund, Erik;

    2012-01-01

    This paper describes a probabilistic approach to calculate the reliability of adhesive bonded composite stepped lap joints loaded in fatigue using three- dimensional finite element analysis (FEA). A method for progressive damage modelling is used to assess fatigue damage accumulation and residual...... strength under fully reversed cyclic loading based on stiffness/strength degradation. The FEA simulations are conducted using the commercial FEA code ANSYS 12.1. A design equation for fatigue failure of wind turbine blades is chosen based on recommendations given in the wind turbine standard IEC 61400...... by the wind turbine standard IEC 61400-1. Finally, an approach for the assessment of the reliability of adhesive bonded composite stepped lap joints loaded in fatigue is presented. The introduced methodology can be applied in the same way to calculate the reliability level of wind turbine blade...

  14. Influence of adhesive layer properties on laser-generated ultrasonic waves in thin bonded plates

    Sun Hong-Xiang; Xu Bai-Qiang; Zhang Hua; Gao Qian; Zhang Shu-Yi

    2011-01-01

    This paper studies quantitatively the generation of Lamb waves in thin bonded plates subjected to laser illumination, after considering the viscoelasticity of the adhesive layer. The displacements of such plates have been calculated in the frequency domain by using the finite element method, and the time domain response has been reconstructed by applying an inverse fast Fourier transform. Numerical results are presented showing the normal surface displacement for several configurations: a single aluminum plate, a three-layer bonded plate, and a two-layer plate. The characteristics of the laser-generated Lamb waves for each particular case have been investigated. In addition, the sensitivity of the transient responses to variations of material properties (elastic modulus, viscoelastic modulus, and thickness) of the adhesive layer has been studied in detail.

  15. Characterization of debond growth mechanism in adhesively bonded composites under mode II static and fatigue loadings

    Mall, S.; Kochhar, N. K.

    1988-01-01

    An experimental investigation of adhesively bonded composite joint was conducted to characterize the debond growth mechanism under mode II static and fatigue loadings. For this purpose, end-notched flexure specimens of graphite/epoxy (T300/5208) adherends bonded with EC 3445 adhesive were tested. In all specimen tested, the fatigue failure occurred in the form of cyclic debonding. The present study confirmed the result of previous studies that total strain-energy-release rate is the driving parameter for cyclic debonding. Further, the debond growth resistance under cyclic loading with full shear reversal (i.e., stress ratio, R = -1) is drastically reduced in comparison to the case when subjected to cyclic shear loading with no shear reversal (i.e., R = 0.1).

  16. Casein Phosphopeptide-Amorphous Calcium Phosphate and Shear Bond Strength of Adhesives to Primary Teeth Enamel

    Farokh Gisovar, Elham; Hedayati, Nassim; Shadman, Niloofar; Shafiee, Leila

    2015-01-01

    Background: CPP-ACP (Phosphopeptide-Amorphous Calcium Phosphate) has an important role in caries prevention in pediatric patients. This study was done, because of the great use of CPP-ACP and the need for restoration for teeth treated with CPP-ACP as well as the importance of shear bond strength of adhesives in the success of restorations. Objectives: This study aimed to evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on shear bond strength of dental adhesiv...

  17. Effect of blood contamination with 1-step self-etching adhesives on microtensile bond strength to dentin.

    Yoo, H M; Pereira, P N R

    2006-01-01

    This study evaluated the effect of blood contamination and decontamination methods on the microtensile bond strength of 1-step self-etching adhesive systems to dentin contaminated after adhesive application and light curing. Three commercially available "all-in-one" adhesives (One Up Bond F, Xeno III and Adper Prompt L-Pop) and 1 resin composite (Clearfil AP-X) were used. Third molars that had been stored in distilled water with 0.5% thymol at 4 degrees C were ground with #600 SiC paper under running water to produce a standardized smear layer. The specimens were randomly divided into groups according to the 3 adhesive systems. The adhesive systems were used under 3 conditions: no contamination, which was the control (C); contamination of the light-cured adhesive surface with blood and reapplication of adhesive (Contamination 1) and contamination of the light-cured adhesive surface with blood, then washing, drying and reapplication of the adhesive (Contamination 2). Following light curing of the adhesive, the resin composite was placed in 3 increments up to a 5-mm-thick layer on the bonded surface. All specimens were stored in distilled water at 37 degrees C for 24 hours. The microtensile bond strength was measured using a universal testing machine (EZ test), and data were analyzed by 1-way ANOVA followed by the Duncan test to make comparisons among the groups (p=0.05). After debonding, 5 specimens were selected from each group and examined in a scanning electron microscope to evaluate the modes of fracture. For all adhesives, contamination groups showed lower bond strength than the control (p0.05). For Xeno III and Adper Prompt L-Pop, contamination group #2 showed the lowest bond strength among the groups (p0.05). PMID:17153973

  18. Analytical modeling of mixed-Mode bending behavior of asymmetric adhesively bonded pultruded GFRP joints

    Ševčík, Martin; Shahverdi, M.; Hutař, Pavel; Vassilopoulos, Anastasios P.

    2015-01-01

    Roč. 147, OCT (2015), s. 228-242. ISSN 0013-7944 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068; GA MŠk(CZ) EE2.3.30.0063 Institutional support: RVO:68081723 Keywords : Mixed-Mode delamination * Asymmetric joint * Adhesively bonded joint * Failure criterion * Analytical prediction * GFRP Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 1.767, year: 2014

  19. Effect of Curing Mode on Shear Bond Strength of Self-Adhesive Cement to Composite Blocks

    Jin-Young Kim; Ga-Young Cho; Byoung-Duck Roh; Yooseok Shin

    2016-01-01

    To overcome the disadvantages of computer-aided design/computer-aided manufacturing (CAD/CAM) processed indirect restorations using glass-ceramics and other ceramics, resin nano ceramic, which has high strength and wear resistance with improved polish retention and optical properties, was introduced. The purpose of this study was to evaluate the shear bond strength and fracture pattern of indirect CAD/CAM composite blocks cemented with two self-etch adhesive cements with different curing mode...

  20. Adhesion of Two Bonding Systems to Air-Abraded or Bur-Abraded Human Enamel Surfaces

    Sengun, Abdulkadir; Orucoglu, Hasan; Ipekdal, Ilknur; Ozer, Fusun

    2008-01-01

    Objectives The purpose of this in vitro study was to evaluate whether mechanical alteration of the enamel surfaces with air abrasion and bur abrasion techniques could enhance the bonding performance of a three step and a self etching adhesive resin systems to enamel. Methods 126 extracted lower human incisor teeth were used. The teeth were divided into three groups including 40 teeth each. First group; teeth were used as control and no preparation was made on enamel surfaces, 2nd group; outer...

  1. Three dimensional geometrical and material nonlinear finite element analysis of adhesively bonded joints for marine structures

    Sampathkumar, Narasimhan

    2005-01-01

    The use of adhesive bonding as a structural joining method has been gaining recognition in marine industry in recent years, though it has been widely adopted in other fields such as aerospace, automobiles, trains and in civil constructions. The type of materials used and design practices followed in marine structures are different from what is applied in other disciplines. Therefore new research approaches are required and recent novel ideas are ex- plored in the context of app...

  2. Effect of bromelain enzyme for dentin deproteinization on bond strength of adhesive system

    Kirti Chauhan; Revaplar Siddaveerappa Basavanna; Vasundhara Shivanna

    2015-01-01

    Aims: To assess the deproteinizing effect of bromelain enzyme and compare it with 5% sodium hypochlorite (NaOCl) on shear bond strength before application of the adhesive system. Materials and Methods: A total of 30 extracted human premolars were divided into three groups, each one consisted of 10 teeth. The occlusal surface was wet ground to expose superficial dentin. In Group 1, teeth were etched; in Group 2, teeth were etched and deproteinized with bromelain enzyme; in Group 3, teeth w...

  3. A New Material Model for 2D FE Analysis of Adhesively Bonded Composite Joints

    Zhao, Libin; Wang, Yana; TianLiang QIN; Zhang, Jianyu

    2014-01-01

    Effective and convenient stress analysis techniques play important roles in the analysis and design of adhesively bonded composite joints. A new material model is presented at the level of composite ply according to the orthotropic elastic mechanics theory and plane strain assumption. The model proposed has the potential to reserve nature properties of laminates with ply-to-ply modeling. The equivalent engineering constants in the model are obtained only by the material properties of unidirec...

  4. Effect of digluconate chlorhexidine on bond strength between dental adhesive systems and dentin: A systematic review

    Dimitrios Dionysopoulos

    2016-01-01

    Aim: This study aimed to systematically review the literature for the effect of digluconate chlorhexidine (CHX) on bond strength between dental adhesive systems and dentin of composite restorations. Materials and Methods: The electronic databases that were searched to identify manuscripts for inclusion were Medline via PubMed and Google search engine. The search strategies were computer search of the database and review of reference lists of the related articles. Search words/terms were a...

  5. Characterization of Mixed-Mode Fracture Testing of Adhesively Bonded Wood Specimens

    Nicoli, Edoardo

    2010-01-01

    The primary focus of this thesis was to investigate the critical strain energy release rates (G) for mixed-mode (I/II) fracture of wood adhesive joints. The aims of the study were: (1) quantifying the fracture properties of two material systems, (2) analyzing the aspects that influence the fracture properties of bonded wood, (3) refining test procedures that particularly address layered orthotropic systems in which the layers are not parallel to the laminate faces, of which wood is often a p...

  6. A New Material Model for 2D FE Analysis of Adhesively Bonded Composite Joints

    Libin ZHAO

    2014-12-01

    Full Text Available Effective and convenient stress analysis techniques play important roles in the analysis and design of adhesively bonded composite joints. A new material model is presented at the level of composite ply according to the orthotropic elastic mechanics theory and plane strain assumption. The model proposed has the potential to reserve nature properties of laminates with ply-to-ply modeling. The equivalent engineering constants in the model are obtained only by the material properties of unidirectional composites. Based on commercial FE software ABAQUS, a 2D FE model of a single-lap adhesively bonded joint was established conveniently by using the new model without complex modeling process and much professional knowledge. Stress distributions in adhesive were compared with the numerical results by Tsai and Morton and interlaminar stresses between adhesive and adherents were compared with the results from a detailed 3D FE analysis. Good agreements in both cases verify the validity of the proposed model. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.5960

  7. Microtensile Bond Strength of Self-Adhesive Luting Cements to Ceramics

    Tomoko Abo

    2012-01-01

    Full Text Available The purpose of this paper was to compare the bond strengths of the self-adhesive luting cements between ceramics and resin cores and examine their relation to the cement thickness. Three self-adhesive luting cements (Smartcem, Maxcem, and G-CEM and a resin cement (Panavia F 2.0 for control were used in the paper. The thickness of the cements was controlled in approximately 25, 50, 100, or 200 μm. Each 10 specimens were made according to the manufacturers’ instructions and stored in water at 37°C. After 24 hours, microtensile bond strength (μTBS was measured. There were significant differences in cements. Three self-adhesive cements showed significantly lower μTBSs than control that required both etching and priming before cementation (Tukey, <0.05. The cement thickness of 50 or 100 μm tended to induce the highest μTBSs for each self-adhesive luting cements though no difference was found.

  8. Sacrificial adhesive bonding: a powerful method for fabrication of glass microchips

    Lima, Renato S.; Leão, Paulo A. G. C.; Piazzetta, Maria H. O.; Monteiro, Alessandra M.; Shiroma, Leandro Y.; Gobbi, Angelo L.; Carrilho, Emanuel

    2015-08-01

    A new protocol for fabrication of glass microchips is addressed in this research paper. Initially, the method involves the use of an uncured SU-8 intermediate to seal two glass slides irreversibly as in conventional adhesive bonding-based approaches. Subsequently, an additional step removes the adhesive layer from the channels. This step relies on a selective development to remove the SU-8 only inside the microchannel, generating glass-like surface properties as demonstrated by specific tests. Named sacrificial adhesive layer (SAB), the protocol meets the requirements of an ideal microfabrication technique such as throughput, relatively low cost, feasibility for ultra large-scale integration (ULSI), and high adhesion strength, supporting pressures on the order of 5 MPa. Furthermore, SAB eliminates the use of high temperature, pressure, or potential, enabling the deposition of thin films for electrical or electrochemical experiments. Finally, the SAB protocol is an improvement on SU-8-based bondings described in the literature. Aspects such as substrate/resist adherence, formation of bubbles, and thermal stress were effectively solved by using simple and inexpensive alternatives.

  9. The effect of antimicrobial agents on bond strength of orthodontic adhesives: a meta-analysis of in vitro studies.

    Altmann, A S P; Collares, F M; Leitune, V C B; Samuel, S M W

    2016-02-01

    Antimicrobial orthodontic adhesives aim to reduce white spot lesions' incidence in orthodontic patients, but they should not jeopardizing its properties. Systematic review and meta-analysis were performed to answer the question whether the association of antimicrobial agents with orthodontic adhesives compromises its mechanical properties and whether there is a superior antimicrobial agent. PubMed and Scopus databases. In vitro studies comparing shear bond strength of conventional photo-activated orthodontic adhesives to antimicrobial photo-activated orthodontic adhesives were considered eligible. Search terms included the following: orthodontics, orthodontic, antimicrobial, antibacterial, bactericidal, adhesive, resin, resin composite, bonding agent, bonding system, and bond strength. The searches yielded 494 citations, which turned into 467 after duplicates were discarded. Titles and abstracts were read and 13 publications were selected for full-text reading. Twelve studies were included in the meta-analysis. The global analysis showed no statistically significant difference between control and experimental groups. In the subgroup analysis, only the chlorhexidine subgroup showed a statistically significant difference, where the control groups had higher bond strength than the experimental groups. Many studies on in vitro orthodontic bond strength fail to report test conditions that could affect their outcomes. The pooled in vitro data suggest that adding an antimicrobial agent to an orthodontic adhesive system does not influence bond strength to enamel. It is not possible to state which antimicrobial agent is better to be associated. PMID:26257400

  10. Laser Ablation Surface Preparation of Ti-6A1-4V for Adhesive Bonding

    Palmieri, Frank L.; Watson, Kent A.; Morales, Guillermo; Williams, Thomas; Hicks, Robert; Wohl, Christopher J.; Hopkins, John W.; Connell, John W.

    2012-01-01

    Adhesive bonding offers many advantages over mechanical fastening, but requires certification before it can be incorporated in primary structures for commercial aviation without disbond-arrestment features or redundant load paths. Surface preparation is widely recognized as the key step to producing robust and predictable bonds. Laser ablation imparts both topographical and chemical changes to a surface which can lead to increased bond durability. A laser based process provides an alternative to chemical-dip, manual abrasion and grit blast treatments which are expensive, hazardous, polluting, and less precise. This report documents preliminary testing of a surface preparation technique using laser ablation as a replacement for the chemical etch and abrasive processes currently applied to Ti-6Al-4V alloy adherends. Failure mode, surface roughness, and chemical makeup were analyzed using fluorescence enhanced visualization, microscopy, and X-ray photoelectron spectroscopy, respectively. Single lap shear tests were conducted on bonded and aged specimens to observe bond strength retention and failure mode. Some promising results showed increasing strength and durability of lap shear specimens as laser ablation coverage area and beam intensity increased. Chemical analyses showed trends for surface chemical species which correlated with improved bond strength and durability. Combined, these results suggest that laser ablation is a viable process for inclusion with or/and replacement of one or more currently used titanium surface treatments. On-going work will focus on additional mechanical tests to further demonstrate improved bond durability.

  11. Microleakage of bonded amalgam restorations using different adhesive agents with dye under vacuum: An in vitro study

    Abhishek Parolia; Kundabala, M; Vaibhav Gupta; Mudita Verma; Chandni Batra; Ramya Shenoy; Srikant, N

    2011-01-01

    Aim: In an effort to minimize tooth preparation, yet provide additional retention to compromised tooth structure, bonded amalgam restorations were introduced. Various resin-based adhesives have been tried earlier under bonded amalgam restorations. Still there are controversies regarding the outcome of bonded amalgam restorations regarding their adaptability to the tooth structure and microleakage. Therefore, this study was undertaken to compare the microleakage of bonded amalgam restorations ...

  12. Multiple Coatings can Improve the Bond Durability of One-step Self-etching Adhesive to Primary Dentin

    Lin Ma; Jian-feng Zhou; Quan Jing; Ji-zhi Zhao; Kuo Wan

    2012-01-01

    Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin.Methods Twelve caries-free human primary molars were randomly divided into 2 groups.In group 1,each tooth was hemisected into 2 halves.One half was assigned to the control subgroup 1,which was bonded with a commercially available one-step self-etching adhesive according to the manufacturer's instructions; the other half was assigned to experimental subgroup 1,in which the adhesive was applied three times before light curing.In group 2,one split half tooth was bonded with a commercially available one-step self-etching adhesive according to the manufacturer's instructions; for the other half,three layers of adhesive were applied with each successive layer of light curing.Specimens were stored in 0.9% NaCl containing 0.02% sodium azide at 37℃ for 18 months and then were subjected to microtensile bond strength test and the fracture mode analysis.Results When the adhesive was applied three times before light curing,the bond strength of the experimental subgroup 1 was significandy higher than that of the control subgroup 1 (47.46±13.91 vs.38.12±11.21 MPa,P<0.05).When using the technique of applying multiple layers of adhesive with each successive layer of light curing,no difference was observed in bond strength between the control subgroup and the experimental subgroup (39.40±8.87 vs.40.87±9.33 MPa,P>0.05).Conclusion Multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin when using the technique of light-curing after applying 3 layers of adhesive.

  13. THERMAL CONDUCTIVITY OF LAMINATED VENEER LUMBERS BONDED WITH VARIOUS ADHESIVES AND IMPREGNATED WITH VARIOUS CHEMICALS

    Burhanettin Uysal

    2009-05-01

    Full Text Available Desmodur VTKA and Urea formaldehyde on wooden materials (Scotch pine and oriental beech cut tangentially and radially impregnated with Tanalith-C, creosote, and sodium silicate in layer (3, 4, 5 of laminated veneer lumber (LVLs on thermal conductivity. The lowest thermal conductivity of 0.103 Kcal/mh°C was obtained in Scotch pine, cut tangentially, impregnated with creosote, bonded with urea formaldehyde, and 3 layer LVL. The highest thermal conductivity of 0.185 Kcal/mh°C was obtained in oriental beech, cut radially, impregnated with Tanalith-C, bonded with PVAc, and 5 layers LVL. Consequently, oriental beech wood cut radially and impregnated with Tanalith-C, bonded with PVAc adhesive and 5 layers in LVL can be used as a material in construction where the thermal conductivity is required. Scotch pine wood cut tangentially and impregnated with creosote, bonded with urea formaldehyde adhesive and 3 layers in LVL can be used as a material in construction where the insulation is required.

  14. Mode-I Fracture in Bonded Wood: Studies of Adhesive Thermal Stability, and of the Effects of Wood Surface Deactivation

    Gao, Tian

    2010-01-01

    This work included two separate studies; the common theme in each was the use of mode-I fracture testing to evaluate wood adhesion. In the first study, mode-I fracture testing was used to compare the thermal stability of polyurethane (PUR) and resorcinol-formaldehyde (RF) wood adhesives. Bonded specimens for both adhesives were subjected to prolonged thermal exposure, and fracture testing was subsequently conducted after re-equilibration to standard test conditions. It was found that both ...

  15. Effect of delayed insertion of composite resin on the bond strength of etch-and-rinse adhesive systems

    Edson Alves CAMPOS

    2009-12-01

    Full Text Available Introduction: Etch-and-rinse adhesive systems are characterized bythe dental acid etching previously to the monomer application. Thesematerials can be classified as 3-step (when primer and bond are applied separately or 2-step (when the primer and bond functions are carried out by a single component. Objective: To determine the influence of immediate or delayed insertion of restorative material on the values of bond strength of 2-step and 3-step etch-and-rinse adhesive systems using the microtensile test. Material and methods: Bovine incisors were used, which had its vestibular surface abraded to obtain a flat dentin surface. 3-step (Scotchbond Multi-Purpose – SMP; Optibond FL – OFL; Bond-It – BIT and 2-step (Single-Bond – SB; Optibond Solo Plus – OSP; Bond-1 – B1 etch-and-rinse adhesive systems were used, and composite resin (Z-350 was adhered to this substrate at two different times: immediately and later (after 24 hours. Procedures were performed with simulated physiological pulpal pressure. Results were submitted to statistical analysis through Anova and Tukey’s test (p < 0.05. Results: When the composite resin was immediately inserted all the adhesive systems showed similar results. 3-step adhesive systems did not show reduction in bond strength values related to delayed insertion of composite. On the other hand, 2-step adhesive systems showed significant reduction in the values of bond strength. Reduction was around 30.24% to SB, 27.19% to OSP and 28.21% to B1. Conclusion: 2-step etch-and-rinse adhesive systems should be used very carefully. It is advisable to insert and polymerize the composite resin immediately after the conclusion of adhesive procedure.

  16. Influence of previous acid etching on interface morphology and bond strength of self-etching adhesive to cavosurface enamel

    Lima, Adriano Fonseca; da Silva, Vinícius Brito; Soares, Giulliana Panfiglio; Marchi, Giselle Maria; Baggio Aguiar, Flávio Henrique; Lovadino, José Roberto

    2012-01-01

    Objectives: The aim of this study was to evaluate the (1) bond strength of a etch-and-rinse and self-etching adhesive systems to cavosurface enamel, (2) influence of the previous acid etching with phosphoric acid 35% to the self-etching adhesive application on bond strength values, and (3) analysis of the cavosurface enamel morphology submitted to different types of conditioning, with the use of a scanning electronic microscope (SEM). Methods: Twenty four human third molars were sectioned on ...

  17. CARIOSTATIC EFFECT AND FLUORIDE RELEASE FROM A VISIBLE LIGHT-CURING ADHESIVE FOR BONDING OF ORTHODONTIC BRACKETS

    OGAARD, B; REZKLEGA, F; RUBEN, J; ARENDS, J

    1992-01-01

    This study was designed to investigate the cariostatic potential in vivo of a visible light-curing adhesive for the bonding of orthodontic brackets. The fluoride release of the adhesive in water and saliva was also measured. Ten orthodontic patients with premolars to be extracted participated. One b

  18. Adhesive bonding and brazing of nanocrystalline diamond foil onto different substrate materials

    Lodes, Matthias A.; Sailer, Stefan; Rosiwal, Stefan M.; Singer, Robert F.

    2013-10-01

    Diamond coatings are used in heavily stressed industrial applications to reduce friction and wear. Hot-filament chemical vapour deposition (HFCVD) is the favourable coating method, as it allows a coating of large surface areas with high homogeneity. Due to the high temperatures occurring in this CVD-process, the selection of substrate materials is limited. With the desire to coat light materials, steels and polymers a new approach has been developed. First, by using temperature-stable templates in the HFCVD and stripping off the diamond layer afterwards, a flexible, up to 150 μm thick and free standing nanocrystalline diamond foil (NCDF) can be produced. Afterwards, these NCDF can be applied on technical components through bonding and brazing, allowing any material as substrate. This two-step process offers the possibility to join a diamond layer on any desired surface. With a modified scratch test and Rockwell indentation testing the adhesion strength of NCDF on aluminium and steel is analysed. The results show that sufficient adhesion strength is reached both on steel and aluminium. The thermal stress in the substrates is very low and if failure occurs, cracks grow undercritically. Adhesion strength is even higher for the brazed samples, but here crack growth is critical, delaminating the diamond layer to some extent. In comparison to a sample directly coated with diamond, using a high-temperature CVD interlayer, the brazed as well as the adhesively bonded samples show very good performance, proving their competitiveness. A high support of the bonding layer could be identified as crucial, though in some cases a lower stiffness of the latter might be acceptable considering the possibility to completely avoid thermal stresses which occur during joining at higher temperatures.

  19. Bonding Analysis of Amino Resin Wood Adhesive with Pesticide Using Response Surface Method

    Bono, Awang; Rajin, Mariani; Siambun, Nancy Julius

    Wood base industries are among the dominant players in Malaysia economic activities. In this research, by using Response Surface Method (RSM), studies of bonding between Disodium Tetraborate Decahydrate (DTD) pesticide and various formulation of wood adhesive i.e., Melamine-Urea-Formaldehyde (MUF) resin is carried out. The RSM formulated twenty-five MUF formulations, consisting combination of different amount of formaldehyde, melamine, urea added in stage-1 and stage-2 of resin synthesis and DTD pesticide. The liquid products of resin are then hardened and tested using Fourier Transformation Infra-Red (FTIR) and visible spectrophotometer (VIS), to analyse the bonding of the resin and pesticide. The data from the FTIR and VIS analysis were then compiled and analysed using Response Surface Method. The results show that, different amount of the formaldehyde, melamine, urea and DTD pesticide, gives specific impact to the strength of MUF resin-pesticide bonding.

  20. Mechanical switching and coupling between two dissociation pathways in a P-selectin adhesion bond

    Evans, Evan; Leung, Andrew; Heinrich, Volkmar; Zhu, Cheng

    2004-08-01

    Many biomolecular bonds exhibit a mechanical strength that increases in proportion to the logarithm of the rate of force application. Consistent with exponential decrease in bond lifetime under rising force, this kinetically limited failure reflects dissociation along a single thermodynamic pathway impeded by a sharp free energy barrier. Using a sensitive force probe to test the leukocyte adhesion bond P-selectin glycoprotein ligand 1 (PSGL-1)-P-selectin, we observed a linear increase of bond strength with each 10-fold increase in the rate of force application from 300 to 30,000 pN/sec, implying a single pathway for failure. However, the strength and lifetime of PSGL-1-P-selectin bonds dropped anomalously when loaded below 300 pN/sec, demonstrating unexpectedly faster dissociation and a possible second pathway for failure. Remarkably, if first loaded by a "jump" in force to 20-30 pN, the bonds became strong when subjected to a force ramp as slow as 30 pN/sec and exhibited the same single-pathway kinetics under all force rates. Applied in this way, a new "jump/ramp" mode of force spectroscopy was used to show that the PSGL-1-P-selectin bond behaves as a mechanochemical switch where force history selects between two dissociation pathways with markedly different properties. Furthermore, replacing PSGL-1 by variants of its 19-aa N terminus and by the crucial tetrasaccharide sialyl LewisX produces dramatic changes in the failure kinetics, suggesting a structural basis for the two pathways. The two-pathway switch seems to provide a mechanism for the "catch bond" response observed recently with PSGL-1-P-selectin bonds subjected to small-constant forces.

  1. In vitro evaluation of the bonding durability of self-adhesive resin cement to titanium using highly accelerated life test.

    Lin, Jie; Shinya, Akikazu; Gomi, Harunori; Matinlinna, Jukka Pekka; Shinya, Akiyoshi

    2011-01-01

    The purpose of this in vitro study was to evaluate the bonding durability of three self-adhesive resin cements to titanium using the Highly Accelerated Life Test (HALT). The following self-adhesive resin cements were used to bond pairs of titanium blocks together according to manufacturers' instructions: RelyX Unicem, Breeze, and Clearfil SA Luting. After storage in water at 37°C for 24 h, bonded specimens (n=15) immersed in 37°C water were subjected to cyclic shear load testing regimes of 20, 30, or 40 kg using a fatigue testing machine. Cyclic loading continued until failure occurred, and the number of cycles taken to reach failure was recorded. The bonding durability of a self-adhesive resin cement to titanium was largely influenced by the weight of impact load. HALT showed that Clearfil SA Luting, which contained MDP monomer, yielded the highest median bonding lifetime to titanium. PMID:22123007

  2. Tensile bond strength of indirect composites luted with three new self-adhesive resin cements to dentin

    Cafer Türkmen

    2011-08-01

    Full Text Available OBJECTIVE: The aims of this study were to evaluate the tensile bond strengths between indirect composites and dentin of 3 recently developed self-adhesive resin cements and to determine mode of failure by SEM. MATERIAL AND METHODS: Exposed dentin surfaces of 70 mandibular third molars were used. Teeth were randomly divided into 7 groups: Group 1 (control group: direct composite resin restoration (Alert with etch-and-rinse adhesive system (Bond 1 primer/adhesive, Group 2: indirect composite restoration (Estenia luted with a resin cement (Cement-It combined with the same etch-and-rinse adhesive, Group 3: direct composite resin restoration with self-etch adhesive system (Nano-Bond, Group 4: indirect composite restoration luted with the resin cement combined with the same self-etch adhesive, Groups 5-7: indirect composite restoration luted with self-adhesive resin cements (RelyX Unicem, Maxcem, and Embrace WetBond, respectively onto the non-pretreated dentin surfaces. Tensile bond strengths of groups were tested with a universal testing machine at a constant speed of 1 mm/min using a 50 kgf load cell. Results were statistically analyzed by the Student's t-test. The failure modes of all groups were also evaluated. RESULTS: The indirect composite restorations luted with the self-adhesive resin cements (groups 5-7 showed better results compared to the other groups (p0.05. The surfaces of all debonded specimens showed evidence of both adhesive and cohesive failure. CONCLUSION: The new universal self-adhesive resins may be considered an alternative for luting indirect composite restorations onto non-pretreated dentin surfaces.

  3. Depletion of water molecules during ethanol wet-bonding with etch and rinse dental adhesives

    The treatment of demineralized dentin with ethanol has been proposed as a way to improve hydrophobic monomer penetration into otherwise water saturated collagen fibrils. The ethanol rinse is expected to preserve the fibrils from collapsing while optimizing resin constituent infiltration for better long term adhesion. The physico-chemical investigations of demineralized dentin confirmed objectively these working hypotheses. Namely, Differential Scanning Calorimetry (DSC) measurements of the melting point of water molecules pointed to the presence of free and bound water states. Unfreezable water was the main type of water remaining following a rinsing step with absolute ethanol. Two different liquid water phases were also observed by Magic Angle Spinning (MAS) solid state Nuclear magnetic Resonance (NMR) spectroscopy. Infrared spectra of ethanol treated specimens illustrated differences with the fully hydrated specimens concerning the polar carbonyl vibrations. Optical microscopy observations as well as scanning electron microscopy showed an improved dentin-adhesive interface with ethanol wet bonding. The results indicate that water can be confined to strongly bound structural molecules when excess water is removed with ethanol prior to adhesive application. This should preserve collagen from hydrolysis upon aging of the hybrid layer. - Highlights: ► Non-freezable water exists in demineralized dentine. ► Free water can be removed by ethanol rinse of the demineralized collagen. ► Ethanol wet bonding leads to a homogeneous hybrid layer free of defects.

  4. Depletion of water molecules during ethanol wet-bonding with etch and rinse dental adhesives

    Gregoire, Genevieve, E-mail: gregoire@cict.fr [Department of Biomaterials, Faculty of Odontology, University Toulouse III, 31062, Toulouse (France); Sharrock, Patrick [Medical and Spatial Imaging Laboratory, University Toulouse III, Ave. Pompidou, 81104, Castres (France); Delannee, Mathieu [Department of Biomaterials, Faculty of Odontology, University Toulouse III, 31062, Toulouse (France); Delisle, Marie-Bernadette [Faculty of Medicine, University Toulouse III, 31062, Toulouse (France)

    2013-01-01

    The treatment of demineralized dentin with ethanol has been proposed as a way to improve hydrophobic monomer penetration into otherwise water saturated collagen fibrils. The ethanol rinse is expected to preserve the fibrils from collapsing while optimizing resin constituent infiltration for better long term adhesion. The physico-chemical investigations of demineralized dentin confirmed objectively these working hypotheses. Namely, Differential Scanning Calorimetry (DSC) measurements of the melting point of water molecules pointed to the presence of free and bound water states. Unfreezable water was the main type of water remaining following a rinsing step with absolute ethanol. Two different liquid water phases were also observed by Magic Angle Spinning (MAS) solid state Nuclear magnetic Resonance (NMR) spectroscopy. Infrared spectra of ethanol treated specimens illustrated differences with the fully hydrated specimens concerning the polar carbonyl vibrations. Optical microscopy observations as well as scanning electron microscopy showed an improved dentin-adhesive interface with ethanol wet bonding. The results indicate that water can be confined to strongly bound structural molecules when excess water is removed with ethanol prior to adhesive application. This should preserve collagen from hydrolysis upon aging of the hybrid layer. - Highlights: Black-Right-Pointing-Pointer Non-freezable water exists in demineralized dentine. Black-Right-Pointing-Pointer Free water can be removed by ethanol rinse of the demineralized collagen. Black-Right-Pointing-Pointer Ethanol wet bonding leads to a homogeneous hybrid layer free of defects.

  5. Effect of EDTA and Phosphoric Acid Pretreatment on the Bonding Effectiveness of Self-Etch Adhesives to Ground Enamel

    Ibrahim, Ihab M.; Elkassas, Dina W.; Yousry, Mai M.

    2010-01-01

    Objectives: This in vitro study determined the effect of enamel pretreatment with phosphoric acid and ethylenediaminetetraacetic acid (EDTA) on the bond strength of strong, intermediary strong, and mild self-etching adhesive systems. Methods: Ninety sound human premolars were used. Resin composite cylinders were bonded to flat ground enamel surfaces using three self-etching adhesive systems: strong Adper Prompt L-Pop (pH=0.9–1.0), intermediary strong AdheSE (pH=1.6–1.7), and mild Frog (pH=2)....

  6. Nanoleakage of dentin adhesive systems bonded to Carisolv-treated dentin.

    Kubo, Shisei; Li, Heping; Burrow, Michael F; Tyas, Martin J

    2002-01-01

    The hybrid layer created in caries-affected dentin has not been fully elucidated and may influence bond durability. This study investigated the nanoleakage patterns of caries-affected dentin after excavation with Carisolv or conventional instruments treated with one of three adhesive systems. Flat occlusal dentin surfaces, including carious lesions, were prepared from extracted human molars and finished with wet 600-grit silicon carbide paper. Carious dentin was removed with Carisolv or round steel burs in conjunction with Caries Detector. PermaQuik, Single Bond or One-Up Bond F was bonded to the excavated dentin surfaces and adjacent flat occlusal surfaces and it was covered with Silux Plus resin-based composite. After 24-hour storage in 37 degrees C water, the bonded interfaces were polished to remove flash, and the surrounding tooth surfaces were coated with nail varnish. Specimens were immersed in 50% (w/v) silver nitrate solution for 24 hours, exposed to photo developing solution for eight hours, then sectioned longitudinally through the bonded, excavated dentin or "normal" dentin surfaces. The sectioned surfaces were polished, carbon coated and observed in a Field Emission-SEM using back scattered electrons. Silver deposition occurred along the base of the hybrid layer for all specimens. However, Single Bond showed a greater density of silver deposition in the caries-affected dentin compared with normal dentin. PermaQuik had a thicker hybrid layer in caries-affected dentin than normal dentin. One-Up Bond F exhibited a thin hybrid layer in normal dentin, but the hybrid layer was often difficult to detect in caries-affected dentin. PMID:12120777

  7. Assessment of the Shear Bond Strength between Nanofilled Composite Bonded to Glass-ionomer Cement Using Self-etch Adhesive with Different pHs and Total-Etch Adhesive

    Farahnaz Sharafeddin; Mohammad Mehdi Choobineh

    2016-01-01

    Statement of the Problem: In the sandwich technique, the undesirable bond between the composite resin and glass-ionomer cement (GIc) is one of the most important factors which lead to the failure of restoration. Total-etch and self-etch adhesives may improve the bond strength based on their pH. Purpose: The purpose of this study was to evaluate the shear bond strength between the nanofilled composite resin and GIc using different adhesives. Materials and Method: In this experimental stu...

  8. Effect of delayed insertion of composite resin on the bond strength of self-etching adhesive systems

    Osmir Batista OLIVEIRA JÚNIOR

    2009-09-01

    Full Text Available Introduction: Technological advances in adhesive systems haveresulted in materials with simplified techniques, which require lessclinical steps. Objective: To determine the influence of immediate ordelayed insertion of restorative material on the values of bond strength self-etching adhesives by using the micro tensile test. Material and methods: Bovine incisors were used, which had its vestibular surface abraded to obtain a flat dentin surface. Self-etching adhesive systems were used: Clearfil SE Bond (CSEB, Clearfil Tri S Bond (CTSB,AdheSE (ADS and AdheSE One (ADO. The composite resin Z350 was adhered to this substrate at two different times: immediately and later (after 24 hours. Procedures were performed with simulated physiological pulpal pressure. Results were submitted to statistical analysis through Anova and Tukey’s test. Results: Except ADS, all materials tested showed reduction of the values of bond strength when composite resin was applied delayed, and only for single-step systems(CTSB and ADO this reduction was statistically significant.Conclusion: Special care shall be taken when using single-step self-etching adhesive systems. It is recommended the application of an additional layer of hydrophobic material in order to reduce permeation of adhesive layer, and the insertion of composite resin should be initiated immediately after the photopolymerization of adhesive system.

  9. Asymptotic Sampling for Reliability Analysis of Adhesive Bonded Stepped Lap Composite Joints

    Kimiaeifar, Amin; Lund, Erik; Thomsen, Ole Thybo;

    2013-01-01

    is a promising and time efficient tool to calculate the probability of failure, is utilized, and a probabilistic model for the reliability analysis of adhesive bonded stepped lap composite joints, representative for the main laminate in a wind turbine blade subjected to static flapwise bending load......Reliability analysis coupled with finite element analysis (FEA) of composite structures is computationally very demanding and requires a large number of simulations to achieve an accurate prediction of the probability of failure with a small standard error. In this paper Asymptotic Sampling, which...... used to predict failure in the composite and adhesive layers, respectively, and the results are compared with the target reliability level implicitly used in the wind turbine standard IEC 61400-1. The accuracy and efficiency of Asymptotic Sampling is investigated by comparing the results with...

  10. SHEAR STRENGTH OF HEAT-TREATED TALI (ERYTHROPHLEUM IVORENSE AND IROKO (CHLOROPHORA EXCELSA WOODS, BONDED WITH VARIOUS ADHESIVES

    Hamiyet Sahin Kol

    2009-11-01

    Full Text Available The aim of this study was to evaluate the effect of heat treatment on the shear strength of tali (Erythrophleum ivorense and iroko (Chlorophora excelsa woods, bonded with some structural adhesives. Shear strength of untreated and heat-treated woods bonded with phenol-formaldehyde (PF, melamine-urea-formaldehyde (MUF, melamine-formaldehyde (MF, and polyurethane (PUR adhesives was studied. An industrial heat treatment method (ThermoWood was used. The timbers were thermally modified for 2 hours at 180 ºC. Laminated samples having two sample sets were prepared from untreated and heat-treated wood for the shear strength test. The results of the tests showed that the heat treatment affected shear strength of laminated wood negatively. Although there was a considerable difference in adhesive bond shear strength between untreated and treated wood, both wood species bonded with the adhesives fulfilled the required value for shear strength of the adhesive bonds. PF, MUF, MF, and PUR adhesives performed in a rather similar way for both wood species.

  11. Supersonic Retropulsion Surface Preparation of Carbon Fiber Reinforced Epoxy Composites for Adhesive Bonding

    Palmieri, Frank L.; Belcher, Marcus A.; Wohl, Christopher J.; Blohowiak, Kay Y.; Connell, John W.

    2013-01-01

    Surface preparation is widely recognized as a key step to producing robust and predictable bonds in a precise and reproducible manner. Standard surface preparation techniques, including grit blasting, manual abrasion, and peel ply, can lack precision and reproducibility, which can lead to variation in surface properties and subsequent bonding performance. The use of a laser to ablate composite surface resin can provide an efficient, precise, and reproducible means of preparing composite surfaces for adhesive bonding. Advantages include elimination of physical waste (i.e., grit media and sacrificial peel ply layers that ultimately require disposal), reduction in process variability due to increased precision (e.g. increased reproducibility), and automation of surface preparation, all of which improve reliability and process control. This paper describes a Nd:YAG laser surface preparation technique for composite substrates and the mechanical performance and failure modes of bonded laminates thus prepared. Additionally, bonded specimens were aged in a hot, wet environment for approximately one year and subsequently mechanically tested. The results of a one year hygrothermal aging study will be presented.

  12. Assessment of the Shear Bond Strength between Nanofilled Composite Bonded to Glass-ionomer Cement Using Self-etch Adhesive with Different pHs and Total-Etch Adhesive

    Farahnaz Sharafeddin

    2016-03-01

    Full Text Available Statement of the Problem: In the sandwich technique, the undesirable bond between the composite resin and glass-ionomer cement (GIc is one of the most important factors which lead to the failure of restoration. Total-etch and self-etch adhesives may improve the bond strength based on their pH. Purpose: The purpose of this study was to evaluate the shear bond strength between the nanofilled composite resin and GIc using different adhesives. Materials and Method: In this experimental study, 40 specimens (6×6mm in 4 groups (n=10 were prepared in acrylic mold. Each specimen contained conventional GI ChemFil Superior with a height of 3mm, bonded to Z350 composite resin with a height measured 3mm. In order to bond the composite to the GI, the following adhesives were used, respectively: A: mild Clearfil SE Bond self-etch (pH=2, B: intermediate OptiBond self-etch (pH=1.4, C: strong Adper Prompt L-Pop (pH=1, and D: Adper Single Bond 2 total-etch (pH=7.2. The shear bond strength was measured by using universal testing machine with a crosshead speed of 1mm/min. One-way ANOVA and Tukey’s test were used to analyze the data (p< 0.05. Results: The shear bond strength in group A was significantly higher than group B (p= 0.002, C (p< 0.001, and D (p< 0.001. Moreover, the shear bond strength of groups A and B (self-etch was significantly different from group D (total-etch (p< 0.001; and C (self-etch with D (p= 0.024. Conclusion: The results of this study showed that applying the mild self-etch adhesive between the composite and the GIc results in stronger shear bond strength compared to intermediate and strong self-etch adhesives. Moreover, the self-etch adhesive increased the shear bond strength between composite resin and GIc more significantly than total-etch adhesive.

  13. Dentin Bond Strength of Two One-Bottle Adhesives after Delayed Activation of Light-Cured Resin Composites

    F. Shafiei

    2007-12-01

    Full Text Available Objective: Adverse surface interactions between one-bottle adhesives and chemical-cured composites may occur with delayed light activation of light-cured composites. The purpose of this study was to assess the Effects of delayed activation of light-cured compositeson shear bond strength of two one-bottle adhesives with different acidity to bovine dentin.Materials and Methods: Flat dentin surface was prepared on sixty-six bovine incisors using 600 grit carbide papers. Prime&Bond NT, and One-Step adhesives and resin composite were applied in six groups: 1 immediate curing of the composite, 2 the composite was left 2.5 minutes over the cured adhesive before light activation, 3 prior to delayed activation of the composite, the cured adhesive was covered with a layer of nonacidic hydrophobic porcelain bonding resin (Choice 2 and cured immediately. After thermocycling,shear bond strength (SBS test was performed using a universal testing machine at 1 mm/min crosshead speed. Data were analyzed with Friedmans two-way Non-parametric ANOVA.Results: The SBS of delayed activation of Prime&Bond was significantly lower than immediate activated (P<0.05. Decrease in the SBS of One-Step was not statistically significant after delayed activation. The SBS of delayed activation of Prime&Bond and One-Step with an additional resin layer was significantly higher than delayed activation (P<0.001.Conclusion: The bond strength of Prime&Bond might be compromised by the higher acidity of this adhesive during the 2.5 minutes delayed activation of light-cured composite.Addition of a layer of hydrophobic resin compensated the effect of delayed activation andimproved the bond strength.

  14. Shear Bond Strengths of Methacrylate- and Silorane-based Composite Resins to Feldspathic Porcelain using Different Adhesive Systems.

    Mohammadi, Narmin; Shakur Shahabi, Maryam; Kimyai, Soodabeh; Pournagi Azar, Fatemeh; Ebrahimi Chaharom, Mohammad Esmaeel

    2015-01-01

    Background and aims. Use of porcelain as inlays, laminates and metal-ceramic and all-ceramic crowns is common in modern dentistry. The high cost of ceramic restorations, time limitations and difficulty of removing these restorations result in delays in replacing fractured restorations; therefore, their repair is indicated. The aim of the present study was to compare the shear bond strengths of two types of composite resins (methacrylate-based and silorane-based) to porcelain, using three adhesive types. Materials and methods. A total of 156 samples of feldspathic porcelain surfaces were prepared with air-abrasion and randomly divided into 6 groups (n=26). In groups 1-3, Z250 composite resin was used to repair porcelain samples with Ad-per Single Bond 2 (ASB), Clearfil SE Bond (CSB) and Silorane Adhesive (SA) as the bonding systems, afterapplication of silane, respectively. In groups 4-6, the same adhesives were used in the same manner with Filtek Silorane composite resin. Finally, the shear bond strengths of the samples were measured. Two-way ANOVA and post hoc Tukey tests were used to compare bond strengths between the groups with different adhesives at P<0.05. Results. There were significant differences in the mean bond strength values in terms of the adhesive type (P<0.001). In addition, the interactive effect of the adhesive type and composite resin type had no significant effect on bond strength (P=0.602). Conclusion. The results of the present study showed the highest repair bond strength values to porcelain with both composite resin types with the application of SA and ASB. PMID:26697151

  15. Shear Bond Strengths of Methacrylate- and Silorane-based Composite Resins to Feldspathic Porcelain using Different Adhesive Systems

    Mohammadi, Narmin; Shakur Shahabi, Maryam; Kimyai, Soodabeh; Pournagi Azar, Fatemeh; Ebrahimi Chaharom, Mohammad Esmaeel

    2015-01-01

    Background and aims. Use of porcelain as inlays, laminates and metal-ceramic and all-ceramic crowns is common in modern dentistry. The high cost of ceramic restorations, time limitations and difficulty of removing these restorations result in delays in replacing fractured restorations; therefore, their repair is indicated. The aim of the present study was to compare the shear bond strengths of two types of composite resins (methacrylate-based and silorane-based) to porcelain, using three adhesive types. Materials and methods. A total of 156 samples of feldspathic porcelain surfaces were prepared with air-abrasion and randomly divided into 6 groups (n=26). In groups 1-3, Z250 composite resin was used to repair porcelain samples with Ad-per Single Bond 2 (ASB), Clearfil SE Bond (CSB) and Silorane Adhesive (SA) as the bonding systems, afterapplication of silane, respectively. In groups 4-6, the same adhesives were used in the same manner with Filtek Silorane composite resin. Finally, the shear bond strengths of the samples were measured. Two-way ANOVA and post hoc Tukey tests were used to compare bond strengths between the groups with different adhesives at P<0.05. Results. There were significant differences in the mean bond strength values in terms of the adhesive type (P<0.001). In addition, the interactive effect of the adhesive type and composite resin type had no significant effect on bond strength (P=0.602). Conclusion. The results of the present study showed the highest repair bond strength values to porcelain with both composite resin types with the application of SA and ASB. PMID:26697151

  16. Adhesives in Building--Lamination of Structural Timber Beams, Bonding of Cementitious Materials, Bonding of Gypsum Drywall Construction. Proceedings of a Conference of the Building Research Institute, Division of Engineering and Industrial Research (Spring 1960).

    National Academy of Sciences - National Research Council, Washington, DC.

    The role of adhesives in building design is discussed. Three major areas are as follows--(1) lamination of structural timber beams, (2) bonding of cementitious materials, and (3) bonding of gypsum drywall construction. Topical coverage includes--(1) structural lamination today, (2) adhesives in use today, (3) new adhesives needed, (4) production…

  17. Laser treatment of carbon fibre reinforced thermoplastic matrix for adhesive bonding

    Genna, S.; Leone, C.; Ucciardello, N.; Giuliani, M.

    2016-05-01

    In the present study, laser surface treatment of CFRP made of PPS thermoplastic matrix by means of a 30 W Q-Switched Yb:YAG fiber laser, is investigated with the aim to improve adhesive bonding. The process parameters pulse power, scanning speed, hatch distance and scanning strategy, were varied to the aim to study the influence of the process condition on the first top resin layer removal and fibre damage. The operating window was experimentally determined. The effectiveness of laser treatment was verified by single lap shear test.

  18. Effect of different adhesive strategies on microtensile bond strength of computer aided design/computer aided manufacturing blocks bonded to dentin

    Roperto, Renato; Akkus, Anna; Akkus, Ozan; Lang, Lisa; Sousa-Neto, Manoel Damiao; Teich, Sorin; Porto, Thiago Soares

    2016-01-01

    Background: The aim of this study was to determine the microtensile bond strength (μTBS) of ceramic and composite computer aided design-computer aided manufacturing (CAD-CAM) blocks bonded to dentin using different adhesive strategies. Materials and Methods: In this in vitro study, 30 crowns of sound freshly extracted human molars were sectioned horizontally 3 mm above the cementoenamel junction to produce flat dentin surfaces. Ceramic and composite CAD/CAM blocks, size 14, were sectioned into slices of 3 mm thick. Before bonding, CAD/CAM block surfaces were treated according to the manufacturer's instructions. Groups were created based on the adhesive strategy used: Group 1 (GI) - conventional resin cement + total-etch adhesive system, Group 2 (GII) - conventional resin cement + self-etch adhesive system, and Group 3 (GIII) - self-adhesive resin cement with no adhesive. Bonded specimens were stored in 100% humidity for 24h at 37΀C, and then sectioned with a slow-speed diamond saw to obtain 1 mm × 1 mm × 6 mm microsticks. Microtensile testing was then conducted using a microtensile tester. μTBS values were expressed in MPa and analyzed by one-way ANOVA with post hoc (Tukey) test at the 5% significance level. Results: Mean values and standard deviations of μTBS (MPa) were 17.68 (±2.71) for GI/ceramic; 17.62 (±3.99) for GI/composite; 13.61 (±6.92) for GII/composite; 12.22 (±4.24) for GII/ceramic; 7.47 (±2.29) for GIII/composite; and 6.48 (±3.10) for GIII/ceramic; ANOVA indicated significant differences among the adhesive modality and block interaction (P CAD/CAM restorations, either composite or ceramic, can be significantly affected by different adhesive strategies used. PMID:27076825

  19. Evaluation of microtensile bond strength of total-etch, self-etch, and glass ionomer adhesive to human dentin: An in vitro study

    Neelima Lakshmi

    2008-01-01

    Full Text Available Aim: To evaluate the microtensile bond strength of Single Bond, AdheSE, and Fuji Bond LC to human dentin. Fifteen non-carious third molars were selected for the study. The teeth were randomly divided into three groups of five teeth each. Each group was given a different bonding treatment. Group I was treated with Single Bond (3M, ESPE, group II with AdheSE (Ivoclar, Vivadent, and group III was treated with Fuji Bond LC (GC America. A T-band metal matrix was placed and composite resin bonded on to the tooth surface using appropriate bonding agents. The composite resin was packed in increments and light cured. Each tooth was sectioned to obtain 1 mm x 1 mm beams of dentin-resin samples. Tensile bond testing was done using a universal testing machine (Instron at a cross-head speed of 0.5 mm/min. Results: The mean bond strength of Single Bond (35.5 MPa was significantly higher than that of AdheSE (32.8 MPa and Fuji Bond LC (32.6 MPa. The difference between the microtensile bond strength values of AdheSE and Fuji Bond LC was statistically insignificant. Inference: Though the bond strength of AdheSE and Fuji Bond LC was above 30 MPa, it was less than that of Single Bond as evaluated by testing of microtensile bond strength.

  20. Resin-dentin bond strength of 10 contemporary etch-and-rinse adhesive systems after one year of water storage.

    Fontes, Silvia Terra; Cubas, Gloria Beatriz de Azevedo; Flores, Josiane Barcelos; Montemezzo, Murieli Leonor; Pinto, Marcia Bueno; Piva, Evandro

    2010-01-01

    To compare the resin-dentin bond degradation of 10 contemporary etch-and-rinse adhesive systems after one year of water storage, 100 bovine incisors were randomly separated into 10 groups and their superficial coronal dentin was exposed. According to manufacturers' instructions, dentin surfaces were bonded with one of seven two-step etch-and-rinse adhesives or one of three three-step etch-and-rinse adhesives. Composite buildups were constructed incrementally. Restored teeth were sectioned to obtain sticks (0.5 mm²). The specimens were subjected to a microtensile bond strength test after storage in distilled water (at 37°C) for one year. Data (MPa) were analyzed using Kruskal-Wallis and Tukey's tests at α = 0.05. Of the adhesives tested, One Step, All Bond 2, and Optibond FL attained the highest bond strength to dentin after one year in water storage, while Magic Bond DE and Master Bond presented a high number of premature debonded flaws. PMID:21062710

  1. Effect of collagen fibrils removal on shear bond strength of total etch and self etch adhesive systems

    Pishevar L.

    2009-12-01

    Full Text Available "nBackground and Aim: Sodium hypochlorite can remove the organic phase of the demineralized dentin and it produces direct resin bonding with hydroxyapatite crystals. Therefore, the hydrolytic degradation of collagen fibrils which might affect the bonding durability is removed. The aim of this study was to evaluate the effect of collagen fibrils removal by 10% NaOCl on dentin shear bond strength of two total etch and self etch adhesive systems."nMaterials and Methods: Sixty extracted human premolar teeth were used in this study. Buccal surface of teeth were grounded until dentin was exposed. Then teeth were divided into four groups. According to dentin surface treatment, experimental groups were as follows: Group I: Single Bond (3M according to manufacture instruction, Group II: 10% NaOCl+Single bond (3M, Group III: Clearfil SE Bond (Kuraray according to manufacture instruction, and Group IV: Clearfil SE Bond primer. After that, the specimens were immersed in 50% acetone solution for removing extra monomer. Then the specimens were rinsed and dried. 10% NaOCl was applied and finally adhesive was used. Then composite was bonded to the treated surfaces using a 4 2 mm cylindrical plastic mold. Specimens were thermocycled for 500 cycles (5-55ºC. A shear load was employed by a universal testing machine with a cross head speed of 1mm/min. The data were analyzed for statistical significance with One-way ANOVA, Two-way ANOVA and Tukey HSD post-hoc tests."nResults: The mean shear bond strengths of groups were as follows: Single Bond=16.8±4.2, Clearfil SE Bond=23.7±4.07, Single Bond+NaOCl=10.5±4.34, Clearfil SE Bond+NaOCl=23.3±3.65 MPa. Statistical analysis revealed that using 10% NaOCl significantly decreased the shear bond strength in Single Bond group (P=0.00, but caused no significant difference in the shear bond strength in Clearfil SE Bond group (P=0.99."nConclusion: Based on the results of this study, NaOCl treatment did not improve the bond

  2. Can previous acid etching increase the bond strength of a self-etching primer adhesive to enamel?

    Ana Paula Morales Cobra Carvalho

    2009-06-01

    Full Text Available Because a greater research effort has been directed to analyzing the adhesive effectiveness of self etch primers to dentin, the aim of this study was to evaluate, by microtensile testing, the bond strength to enamel of a composite resin combined with a conventional adhesive system or with a self-etching primer adhesive, used according to its original prescription or used with previous acid etching. Thirty bovine teeth were divided into 3 groups with 10 teeth each (n= 10. In one of the groups, a self-etching primer (Clearfil SE Bond - Kuraray was applied in accordance with the manufacturer's instructions and, in the other, it was applied after previous acid etching. In the third group, a conventional adhesive system (Scotchbond Multipurpose Plus - 3M-ESPE was applied in accordance with the manufacturer's instructions. The results obtained by analysis of variance revealed significant differences between the adhesive systems (F = 22.31. The self-etching primer (Clearfil SE Bond presented lower enamel bond strength values than the conventional adhesive system (Scotchbond Multipurpose Plus (m = 39.70 ± 7.07 MPa both when used according to the original prescription (m = 27.81 ± 2.64 MPa and with previous acid etching (m = 25.08 ± 4.92 MPa.

  3. The reduction of formaldehyde and VOCs emission from wood-based flooring by green adhesive using cashew nut shell liquid (CNSL).

    Kim, Sumin

    2010-10-15

    To discuss the reduction of formaldehyde and volatile organic compound (VOC) emissions from engineered flooring, cashew nut shell liquid (CNSL)-formaldehyde (CF) resin and CF/PVAc resin were applied for the maple face of the veneer bonding on plywood. The CF resin was used to replace urea-formaldehyde (UF) resin in the formaldehyde-based resin system in order to reduce formaldehyde and VOC emissions from the adhesives used between the plywoods and fancy veneers. For the CF/PVAc resins, 5, 10, 20 or 30% of PVAc was added to the CF resin. The CF/PVAc resins showed better bonding than the commercial natural tannin adhesive with a higher level of wood penetration. The standard formaldehyde emission test and a VOC analyzer were used to determine the formaldehyde and VOC emissions, respectively, from the engineered floorings. The CF resin and CF/PVAc resin systems with UV coating satisfied the E(1) and E(0) grades of the Korean Standard. TVOC emission was slightly increased by the PVAc addition. PMID:20362392

  4. Bond strength of an adhesive system irradiated with Nd:YAG laser in dentin treated with Er:YAG laser

    The purpose of this in vitro study was to verify through micro tensile bond test the bond strength of an adhesive system irradiated with Nd:YAG laser in dentine previously treated with Er:YAG laser. Twenty caries free extracted human third molars were used. The teeth were divided in four experimental groups (n = 5): (G1) control group; (G2) irradiation of the adhesive system with the Nd:YAG laser; (G3) dentin treatment with Er:YAG laser; (G4) dentin treatment with Er:YAG laser followed by the irradiation of the adhesive system with Nd:YAG laser. The Er:YAG laser fluency parameter for the dentin treatment was of 60 J/cm2. The adhesive system was irradiated with the Nd:YAG laser with fluency of 100 J/cm2. Dental restorations were performed with Adper Single Bond 2/Z250. One tooth from each group was prepared for the evaluation of the adhesive interface under SEM and bond failure tests were also performed and evaluated. The statistical analysis showed statistical significant difference between the groups G1 and G3, G1 and G4, G2 and G3, and G2 and G4; and similarity between the groups G1 and G2, and G3 and G4. The adhesive failures were predominant in all the experimental groups. The SEM analysis showed an adhesive interface with features confirming the results of the mechanical tests. The Nd:YAG laser on the adhesive system did not influence the bond strength in dentin treated or not with the Er:YAG laser

  5. Mechanical joining and adhesive bonding - basics, technology, applications; Fuegen durch Umformen und Kleben - Grundlagen, Technologie, Anwendungen

    Meschut, G. [Volkswagen AG, Konzern-Forschung, Wolfsburg (Germany)

    2001-07-01

    This contribution uses material combinations current in the automotive industry to demonstrate the mutual dependence of joining processes and their implications for the geometric shaping of fasteners in the combined shaping and adhesive bonding joining process. The mechanical properties of joints made using combined and elementary methods are compared taking into consideration quasi static, oscillating and impact-type loads, and ageing characteristics. The results demonstrate that the combination of mechanical and adhesive bonding methods produces joints of technologically high quality which can be implemented in optimised light-weight construction. General information is provided on the use of low-heat hybrid joining technology for project planning of this type of connections in industrial practice. (orig.) [German] Der Beitrag verdeutlicht anhand von aktuellen Werkstoffkombinationen aus dem Fahrzeugbau die gegenseitige Beeinflussung der Fuegeprozesse und die Folgen fuer die Fuegeelementausbildung bei der Verfahrenskombination Fuegen durch Umformen und Kleben. Die mechanischen Eigenschaften von kombiniert gefuegten und elementar gefuegten Verbindungen unter quasistatischer, schwingender und stossartiger Belastung sowie das Alterungsverhalten werden gegenuebergestellt. Die Ergebnisse zeigen, dass mittels der Kombination mechanischer Fuegeverfahren mit dem Kleben technologisch hochwertige Verbindungen fuer den eigenschaftsoptimierten Leichtbau realisierbar sind. Fuer die Projektierung derartiger Verbindungen in der industriellen Praxis werden allgemeingueltige Hinweise zum Einsatz der waermearmen Hybridfuegetechnik gegeben. (orig.)

  6. Epoxy Enhanced by Recycled Milled Carbon Fibres in Adhesively-Bonded CFRP for Structural Strengthening

    Chao Wu

    2013-12-01

    Full Text Available This paper investigates the mechanical performance and electrical resistivity of a structural adhesive epoxy enhanced using milled carbon fibre (MCF as well as the bond performance of carbon fibre reinforced polymers (CFRP and steel adhesively bonded joints using the enhanced epoxy. The epoxy was enhanced using such MCFs with different weight ratios of 1.5%, 3% and 5%. Tensile experiments were performed on the original and enhanced epoxy specimens according to ASTM D638. More ductile process failure was found for the epoxy after modification and significant improvements of E-modulus and tensile strength were evidenced when the MCF weight ratio was larger than 1.5%. Scanning electron microscopy (SEM revealed that the failure mechanism of short MCFs pulled out from the epoxy matrix contributed to the enhancement of the mechanical performance of the epoxy. The electrical resistivity of the epoxy with MCF weight ratio of 5% was reduced by at least four orders of magnitude compared to the original epoxy, due to the conductive network formed by MCFs. Steel/CFRP double strap joints (with either CFRP sheets or CFRP laminates were prepared using the enhanced epoxy and then tested in tension, however no obvious increase in joint stiffness or strength was observed.

  7. Air-coupled ultrasonic testing of metal adhesively bonded joints using cellular polypropylene transducers

    Gaal, Mate; Bartusch, Jürgen; Dohse, Elmar; Kreutzbruck, Marc; Amos, Jay

    2014-02-01

    Adhesively bonded aluminum components have been widely used in the aerospace industry for weight-efficient and damage-tolerant structures. Automated squirter jet immersion ultrasonic testing is a common inspection technique to assure the bond integrity of large, contoured assemblies. However, squirter jet inspection presents several limitations in scanning speed, related to water splash noise over protruding stiffeners and splash interference crosstalk in multi-channel inspection systems. Air-coupled ultrasonic testing has been evaluated as an alternative, possibly offering the benefits of increased throughput by enabling higher speeds, and eliminating the contamination concerns and maintenance issues of water couplant systems. Adhesive joints of multi-layer aluminum plates with artificial disbonds were inspected with novel air-coupled ultrasonic probes based on cellular polypropylene. Disbonds of various sizes were engineered in several multi-layer configurations and at various depths. Results were compared with squirter jet immersion and conventional piezoelectric transducer designs in terms of scan contrast, resolution and inspection time.

  8. A completely transparent, adhesively bonded soda-lime glass block masonry system

    F. Oikonomopoulou

    2015-01-01

    Full Text Available A pioneering, all transparent, self-supporting glass block facade is presented in this paper. Previously realized examples utilize embedded metal components in order to obtain the desired structural performance despite the fact that these elements greatly affect the facade’s overall transparency level. Undeniably, the oxymoron ‘transparency and strength’ remains the prime concern in such applications. In this paper, a new, innovative structural system for glass block facades is described, which demonstrably meets both criteria. The structure is exclusively constructed by monolithic glass blocks, bonded with a colourless, UV-curing adhesive, obtaining thus a maximum transparency. In addition, the desired structural performance is achieved solely through the masonry system, without any opaque substructure. Differing from previous realized projects, solid soda-lime glass blocks are used rather than borosilicate ones. This article provides an overview of the integrated architectural and structural design and discusses the choice of materials. The structural verification of the system is demonstrated. The results show that the adhesively bonded glass block structure has the required self-structural behaviour, but only if strict tolerances are met in the geometry of the glass blocks.

  9. A completely transparent, adhesively bonded soda-lime glass block masonry system

    Faidra Oikonomopoulou

    2015-06-01

    Full Text Available A pioneering, all transparent, self-supporting glass block facade is presented in this paper. Previously realized examples utilize embedded metal components in order to obtain the desired structural performance despite the fact that these elements greatly affect the facade’s overall transparency level. Undeniably, the oxymoron ‘transparency and strength’ remains the prime concern in such applications. In this paper, a new, innovative structural system for glass block facades is described, which demonstrably meets both criteria. The structure is exclusively constructed by monolithic glass blocks, bonded with a colourless, UV-curing adhesive, obtaining thus a maximum transparency. In addition, the desired structural performance is achieved solely through the masonry system, without any opaque substructure. Differing from previous realized projects, solid soda-lime glass blocks are used rather than borosilicate ones. This article provides an overview of the integrated architectural and structural design and discusses the choice of materials. The structural verification of the system is demonstrated. The results show that the adhesively bonded glass block structure has the required self-structural behaviour, but only if strict tolerances are met in the geometry of the glass blocks.  

  10. Shear Bond Strength of Orthodontic Brackets Fixed with Remineralizing Adhesive Systems after Simulating One Year of Orthodontic Treatment

    Bezerra, Gisele Lima; Torres, Carlos Rocha Gomes; Tonetto, Mateus Rodrigues; Borges, Alvaro Henrique; Kuga, Milton Carlos; Bandeca, Matheus Coelho; Firoozmand, Leily Macedo

    2015-01-01

    The objective of this study is to assess, in vitro, the shear bond strength of orthodontic brackets fixed with remineralizing adhesive systems submitted to thermomechanical cycling, simulating one year of orthodontic treatment. Sixty-four bovine incisor teeth were randomly divided into 4 experimental groups (n = 16): XT: Transbond XT, QC: Quick Cure, OL: Ortholite Color, and SEP: Transbond Plus Self-Etching Primer. The samples were submitted to thermomechanical cycling simulating one year of orthodontic treatment. Shear bond strength tests were carried out using a universal testing machine with a load cell of 50 KgF at 0.5 mm/minute. The samples were examined with a stereomicroscope and a scanning electron microscope (SEM) in order to analyze enamel surface and Adhesive Remnant Index (ARI). Kruskal-Wallis and Mann-Whitney (with Bonferroni correction) tests showed a significant difference between the studied groups (p < 0.05). Groups XT, QC, and SEP presented the highest values of adhesive resistance and no statistical differences were found between them. The highest frequency of failures between enamel and adhesive was observed in groups XT, QC, and OL. Quick Cure (QC) remineralizing adhesive system presented average adhesive resistance values similar to conventional (XT) and self-etching (SEP) adhesives, while remineralizing system (OL) provided the lowest values of adhesive resistance. PMID:26380371

  11. Bonding Effectiveness of Universal Adhesive to Intracoronal Bleached Dentin Treated with Sodium Ascorbate.

    Trindade, Thaís Fantinato; Moura, Luana Kelle Batista; Raucci, Walter; Messias, Danielle Cristine Furtado; Colucci, Vivian

    2016-01-01

    This study evaluated the effect of restorative protocol with sodium ascorbate on the shear bond strength (SBS) of a universal adhesive to intracoronal bleached dentin. One hundred-and-twenty bovine dentin fragments were randomly divided into 12 groups (n=10), according to the bleaching procedure (unbleached and bleached) and restorative protocol (no treatment, 10% sodium ascorbate -10SA, 35% sodium ascorbate -35SA and two-step etch-and-rinse -ER or one-step self-etch -SE Scotchbond universal adhesive approaches). Four whitening sessions were performed using 35% hydrogen peroxide. The samples from control groups were kept in relative humidity at 37 °C. Immediately after bleaching procedures, the assigned antioxidant solution was applied on dentin and restorative procedures were performed following either the ER or the SE approach. After 24 h, the specimens were subjected to SBS test. Data (MPa) were analyzed by ANOVA and Tukey's test (?=0.05). Lower SBS values were found for bleached specimens (8.54 MPa) compared with those unbleached (12.13 MPa) (pbond strength of the sodium ascorbate-treated groups was higher than those untreated, regardless of the strategy employed (pbond strength values for both ER (8.32 MPa) and SE (8.28 MPa) adhesive strategies. The group treated with 10SA submitted to ER approach (10.14 MPa) was similar to untreated groups (p>0.05). It may be concluded that bond strength of composite resin to intracoronal dentin was affected by restorative protocol and reduced by bleaching. PMID:27224564

  12. Analysis on Adhesively-Bonded Joints of FRP-steel Composite Bridge under Combined Loading: Arcan Test Study and Numerical Modeling

    Xu Jiang; Xuhong Qiang; Henk Kolstein; Frans Bijlaard

    2016-01-01

    The research presented in this paper is an experimental study and numerical analysis on mechanical behavior of the adhesively-bonded joint between FRP sandwich bridge deck and steel girder. Generally, there are three typical stress states in the adhesively-bonded joint: shear stress, tensile stress, and combination of both. To realize these stress states in the adhesively-bonded joint during tests, a specific loading device is developed with the capacity of providing six different loading ang...

  13. Bond strength durability of self-etching adhesives and resin cements to dentin

    Carolina de Andrade Lima Chaves

    2009-06-01

    Full Text Available OBJECTIVES: To evaluate the microtensile bond strength (µTBS of one- (Xeno III, Dentsply and two-step (Tyrian-One Step Plus, Bisco self-etching adhesive systems bonded to dentin and cemented to chemically cured (C&B Metabond or light-cured paste of a dual-cure resin cement (Variolink II, Ivoclar within a short (24 h and long period of evaluation (90 days. MATERIAL AND METHODS: Forty recently extracted human molars had their roots removed and their occlusal dentin exposed and ground wet with 600-grit SiC paper. After application of one of the adhesives, the resin cement was applied to the bonded surface and a composite resin block was incrementally built up to a height of 5 mm (n=10. The restored teeth were stored in distilled water at 37ºC for 7 days. The teeth were then cut along two axes (x and y, producing beam-shaped specimens with 0.8 mm² cross-sectional area, which were subjected to µTBS testing at a crosshead speed of 0.05 mm/min and stressed to failure after 24 h or 90 days of storage in water. The µTBS data in MPa were subjected to three-way analysis of variance and Tukey's test (α= 0.05. RESULTS: The interaction effect for all three factors was statistically significant (three-way ANOVA, p<0.001. All eight experimental means (MPa were compared by the Tukey's test (p<0.05 and the following results were obtained: Tyrian-One Step Plus /C&B/24 h (22.4±7.3; Tyrian-One Step Plus /Variolink II/24 h (39.4±11.6; Xeno III/C&B/24 h (40.3±12.9; Xeno III/Variolink II/24 h (25.8±10.5; Tyrian-One Step Plus /C&B/90 d (22.1±12.8 Tyrian-One Step Plus/VariolinkII/90 d (24.2±14.2; Xeno III/C&B/90 d (27.0±13.5; Xeno III/Variolink II/90 d (33.0±8.9. CONCLUSIONS: Xeno III/Variolink II was the luting agent/adhesive combination that provided the most promising bond strength after 90 days of storage in water.

  14. Damage prognosis of adhesively-bonded joints in laminated composite structural components of unmanned aerial vehicles

    Farrar, Charles R [Los Alamos National Laboratory; Gobbato, Maurizio [UCSD; Conte, Joel [UCSD; Kosmatke, John [UCSD; Oliver, Joseph A [UCSD

    2009-01-01

    The extensive use of lightweight advanced composite materials in unmanned aerial vehicles (UAVs) drastically increases the sensitivity to both fatigue- and impact-induced damage of their critical structural components (e.g., wings and tail stabilizers) during service life. The spar-to-skin adhesive joints are considered one of the most fatigue sensitive subcomponents of a lightweight UAV composite wing with damage progressively evolving from the wing root. This paper presents a comprehensive probabilistic methodology for predicting the remaining service life of adhesively-bonded joints in laminated composite structural components of UAVs. Non-destructive evaluation techniques and Bayesian inference are used to (i) assess the current state of damage of the system and, (ii) update the probability distribution of the damage extent at various locations. A probabilistic model for future loads and a mechanics-based damage model are then used to stochastically propagate damage through the joint. Combined local (e.g., exceedance of a critical damage size) and global (e.g.. flutter instability) failure criteria are finally used to compute the probability of component failure at future times. The applicability and the partial validation of the proposed methodology are then briefly discussed by analyzing the debonding propagation, along a pre-defined adhesive interface, in a simply supported laminated composite beam with solid rectangular cross section, subjected to a concentrated load applied at mid-span. A specially developed Eliler-Bernoulli beam finite element with interlaminar slip along the damageable interface is used in combination with a cohesive zone model to study the fatigue-induced degradation in the adhesive material. The preliminary numerical results presented are promising for the future validation of the methodology.

  15. Effect of saliva contamination on the shear bond strength of a new self-etch adhesive system to dentin

    Swapna Munaga

    2014-01-01

    Full Text Available Aims and Objectives: To evaluate the effect of saliva contamination on the shear bond strength of a new two-step self-etch adhesive (P90 system adhesive to dentin and to determine the effect of contaminant removing treatments on the recovery of bond strengths. Materials and Methods: The buccal surfaces of 40 human premolars were ground to expose dentin. The specimens were randomly divided into four groups. Group 1 is uncontaminated and serves as the control group. Further groups were divided based on the step in the bonding sequence when the contamination had occurred as follows: Group 2 (primer, saliva contamination, rinse and dry, group 3 (after procedure of group 2, reapplication of primer, and group 4 (after procedure like in control group, saliva contamination, rinse and dry. Filtek P90 composite resin cylinders of 3 mm diameter and 3 mm length were fabricated on the surfaces. Shear bond strength testing was done in an Instron Universal Testing Machine and the data were subjected to one-way analysis of variance (ANOVA and Student′s t-test. Results: With P90 system adhesive, group 2 and group 4 showed lower shear bond strength than group 1 (control and group 3 (P < 0.05. Conclusion: Saliva contamination significantly decreased the shear bond strength of the adhesive to dentin.

  16. Dentin bonding performance using Weibull statistics and evaluation of acid-base resistant zone formation of recently introduced adhesives.

    Guan, Rui; Takagaki, Tomohiro; Matsui, Naoko; Sato, Takaaki; Burrow, Michael F; Palamara, Joseph; Nikaido, Toru; Tagami, Junji

    2016-07-30

    Dentin bonding durability of recently introduced dental adhesives: Clearfil SE Bond 2 (SE2), Optibond XTR (XTR), and Scotchbond Universal (SBU) was investigated using Weibull analysis as well as analysis of the micromorphological features of the acid-base resistant zone (ABRZ) created for the adhesives. The bonding procedures of SBU were divided into three subgroups: self-etch (SBS), phosphoric acid (PA) etching on moist (SBM) or dry dentin (SBD). All groups were thermocycled for 0, 5,000 and 10,000 cycles followed by microtensile bond strength testing. Acid-base challenge was undertaken before SEM and TEM observations of the adhesive interface. The etch-and-rinse method with SBU (SBM and SBD) created inferior interfaces on the dentin surface which resulted in reduced bond durability. ABRZ formation was detected with the self-etch adhesive systems; SE2, XTR and SBS. In the PA etching protocols of SBM and SBD, a thick hybrid layer but no ABRZ was detected, which might affect dentin bond durability. PMID:27335136

  17. Effects of adhesive thickness on the Lamb wave pitch-catch signal using bonded piezoelectric wafer transducers

    Islam, M. M.; Huang, H.

    2016-08-01

    This paper investigates the effects of adhesive layer on Lamb wave ultrasound pitch-catch signals that are excited and sensed by piezoelectric wafer transducers bonded on a slender structure. Analytical models were established to simulate the longitudinal and flexural vibrations of the structures separately and parametric studies of the bonding layer properties, i.e. the shear transfer parameter, adhesive thickness, and shear modulus, were performed. The parametric studies indicate that there exists an optimal adhesive layer thickness that generates maximum ultrasound pitch-catch signal for both wave modes. This prediction was subsequently validated by measurements. In addition, an improved match between the measured and simulated pitch-catch signals was achieved by adjusting the adhesive layer parameters.

  18. Effect of dental bleaching after bracket bonding and debonding using three different adhesive systems

    Lucianna de Oliveira Gomes

    2013-04-01

    Full Text Available OBJECTIVE: To evaluate the influence of bonding and debonding of orthodontic brackets on dental in-home bleaching, taking into account three different adhesive systems. METHODS: Forty-four bovine incisors were divided into four groups according to the primer system used for orthodontic bracket bonding. Following the debonding of orthodontic brackets, the teeth were stored in staining solution for 96 hours. Then, teeth were whitened using 10% carbamide peroxide for two weeks at a 6-hour-a-day regime. Standardized digital photographs were taken at the following intervals: T0 (initial; T1 (after debonding; T2 (after pigmentation; T3, T4 and T5 representing 1, 7, and 14 days of bleaching. Repeatability and stability tests were carried out to check the method accuracy. Images were analyzed using Adobe Photoshop 7.0 software considering (L*a*b*color coordinate values and a modified color difference total (Δ;E'. RESULTS: The results of this study (ANOVA and Tukey; p < 0.01 demonstrated that after 7 days of bleaching, experimental groups showed significantly less teeth whitening compared to the control group. However, there were no significant color differences between the groups after 14 days, according to values of lightness (L*. CONCLUSIONS: Regardless of the adhesive primer system applied, bonding and debonding of orthodontic brackets alters the outcome of tooth whitening in the first 7 days of bleaching, however it has no influence on the whitening of the dental structure after 14 days of in-home dental bleaching with 10% carbamide peroxide.

  19. Environment-friendly adhesives for surface bonding of wood-based flooring using natural tannin to reduce formaldehyde and TVOC emission.

    Kim, Sumin

    2009-01-01

    The objective of this research was to develop environment-friendly adhesives for face fancy veneer bonding of engineered flooring using the natural tannin form bark in the wood. The natural wattle tannin adhesive were used to replace UF resin in the formaldehyde-based resin system in order to reduce formaldehyde and volatile organic compound (VOC) emissions from the adhesives used between plywoods and fancy veneers. PVAc was added to the natural tannin adhesive to increase viscosity of tannin adhesive for surface bonding. For tannin/PVAc hybrid adhesives, 5%, 10%, 20% and 30% of PVAc to the natural tannin adhesives were added. tannin/PVAc hybrid adhesives showed better bonding than the commercial natural tannin adhesive with a higher level of wood penetration. The initial adhesion strength was sufficient to be maintained within the optimum initial tack range. The standard formaldehyde emission test (desiccator method), field and laboratory emission cell (FLEC) and VOC analyzer were used to determine the formaldehyde and VOC emissions from engineered flooring bonded with commercial the natural tannin adhesive and tannin/PVAc hybrid adhesives. By desiccator method and FLEC, the formaldehyde emission level of each adhesive showed the similar tendency. All adhesives satisfied the E(1) grade (below 1.5 mg/L) and E(0) grade (below 0.5 mg/L) with UV coating. VOC emission results by FLEC and VOC analyzer were different with the formaldehyde emission results. TVOC emission was slightly increased as adding PVAc. PMID:18710801

  20. Effect of saliva contamination on the microshear bond strength of one-step self-etching adhesive systems to dentin.

    Yoo, H M; Oh, T S; Pereira, P N R

    2006-01-01

    This study evaluated the effect of saliva contamination and decontamination methods on the dentin bond strength of one-step self-etching adhesive systems. Three commercially available "all-in-one" adhesives (One Up Bond F, Xeno III and Adper Prompt) and one resin composite (Filtek Z-250) were used. Third molars stored in distilled water with 0.5% thymol at 4 degrees C were ground with #600 SiC paper under running water to produce a standardized smear layer. The specimens were randomly divided into groups according to contamination methods: no contamination, which was the control (C); contamination of the adhesive surface with fresh saliva before light curing (A) and contamination of the adhesive surface with fresh saliva after light curing (B). Each contamination group was further subdivided into three subgroups according to the decontamination method: A1-Saliva was removed by a gentle air blast and the adhesive was light-cured; A2-Saliva was rinsed for 10 seconds, gently air-dried and the was adhesive light-cured; A3-Saliva was rinsed and dried as in A2, then the adhesive was re-applied to the dentin surface and light-cured; B1-Saliva was removed with a gentle air blast; B2-Saliva was rinsed and dried; B3-Saliva was rinsed, dried and the adhesive was re-applied and light cured. Tygon tubes filled with resin composite were placed on each surface and light cured. All specimens were stored in distilled water at 37 degrees C for 24 hours. Microshear bond strength was measured using a universal testing machine (EZ test), and data were analyzed by one-way ANOVA followed by the Duncan test to make comparisons among the groups (p0.05). Bond strengths of all B groups were significantly lower compared to the controls (p0.05). PMID:16536204

  1. Shear Bond Strength of Saliva Contaminated and Re-etched All-in-One Adhesive to Enamel

    M. Khoroushi

    2008-12-01

    Full Text Available Objective: The aim of this study was to investigate the effect of phosphoric acid re-etching of an enamel surface treated via a one-bottle adhesive system on shear bond strength between resin composite and the enamelsurface in different stages of adhesive application.Materials and Methods: Extracted intact premolars (n=84 were divided into sevengroups (n=12. In the control group 1, the adhesive i-Bond was used according to the manufacturer's instructions, with nocontamination. In groups 2 to 4, the conditioned and saliva, contaminated enamel was blot dried only, rinsed,and blot dried, rinsed blot dried and re-etched, respectively. In groups 5, 6and 7 cured adhesive was contaminated with saliva and then rinsed and blot-dried, blot dried only and rinsed, blot-dried and re-etched respectively. In groups 3, 4, 6 and 7 the adhesive was reapplied. Afterward, Z100 compos-ite cylinders were bonded to the enamel surfaces. The samples were thermocycled (5°C and 55°C, 30 s, dwelling time: 10 s, 500 cycles. Finally, the samples were sheared using Dartec testing machine and shear bond strength data were subjected to one-way ANOVA analysis and Tukey's HSD test.Results: There were statistically significant differences among groups 1 and 5-7. The samples in groups 1 and 4 demonstrated higher bond strengths than those in the other groups.Conclusion: Using phosphoric acid etching may be effective, only where contamination occurs prior to curing of the adhesive. After curing of the adhesive, none of the methods in this study would be preferred.

  2. In-vitro evaluation of an experimental method for bonding of orthodontic brackets with self-adhesive resin cements

    Barat Ali Ramazanzadeh

    2013-01-01

    Full Text Available Background: Self-adhesive resin cements do not require the surface treatment of teeth and are said to release fluoride, which makes them suitable candidates for bonding of orthodontic brackets. The objectives of this study was to investigate the shear bond strength (SBS of self-adhesive resin cements on etched on non-etched surfaces in vitro and to assess their fluoride release features. Materials and Methods: Four fluoride-releasing dual-cure self-adhesive resin cements were investigated. For SBS experiment, 135 freshly extracted human maxillary premolars were used and divided into nine groups of 15 teeth. In the control group, brackets were cemented by Transbond XT (3M Unitek, USA, in four groups self-adhesive resin cements were used without acid-etching and in four groups self-adhesive cements were applied on acid-etched surfaces and the brackets were then deboned in shear with a testing machine. Adhesive remnant index (ARI scores were also calculated. For fluoride release investigation, 6 discs were prepared for each self-adhesive cement. Transbond XT and Fuji Ortho LC (GC, Japan served as negative and positive control groups, respectively. The fluoride release of each disc into 5 ml of de-ionized water was measured at days 1, 2, 3, 7, 14, 28, and 56 using a fluoride ion-selective electrode connected to an ion analyzer. To prevent cumulative measurements, the storage solutions were changed daily. Results: The SBS of brackets cemented with Transbond XT were significantly higher compared to self-adhesives applied on non-etched surfaces (P<0.001. However, when the self-adhesive resin cements were used with enamel etching, no significant differences was found in the SBS compared to Transbond XT, except for Breeze. The comparisons of the ARI scores indicated that bracket failure modes were significantly different between the etched and non-etched groups. All self-adhesive cements released clinically sufficient amounts of fluoride for an extended

  3. Influence of 10-MDP Adhesive System on Shear Bond Strength of Zirconia-Composite Interfaces

    Philipp Cornelius Pott

    2015-09-01

    Full Text Available Introduction: This in-vitro study investigated the initial 24h bond strength between different composites and zirconia after application of four different adhesive systems. Methods: A total of 120 specimens of zirconia (InCoris, Sirona, Germany, Bernsheim were ground with a 165 µm grit rotating diamond disc. Thirty specimens were each additionally treated with Cimara Zircon “CZ” (VOCO GmbH, Germany, Cuxhaven, Futurabond U “FBU” (VOCO GmbH, Futurabond M+ “FBM” (VOCO GmbH or Futurabond M+ in combination with the DCA activator “FBMD” (VOCO GmbH. One of three different types of composites – BifixSE (“BS”, BifixQM (“BQ” or GrandioSO (“G” (VOCO GmbH – was bonded to ten specimens each in every group. Shear bond strength (SBS was determined in a universal testing machine. Statistical analysis was performed with ANOVA and the Tukey test. Results: FBM and FBMD gave higher SBS than CZ and FBU in combination with all tested composites. In comparison to FBU, FBM gave statistically significant increases in SBS with BifixSE (19.4±5.7 MPa (P

  4. Influence of oxygen inhibition on the surface free-energy and dentin bond strength of self-etch adhesives.

    Koga, Kensaku; Tsujimoto, Akimasa; Ishii, Ryo; Iino, Masayoshi; Kotaku, Mayumi; Takamizawa, Toshiki; Tsubota, Keishi; Miyazaki, Masashi

    2011-10-01

    We compared the surface free-energies and dentin bond strengths of single-step self-etch adhesives with and without an oxygen-inhibited layer. The labial dentin surfaces of bovine mandibular incisors were wet ground with #600-grit silicon carbide paper. The adhesives were applied to the ground dentin, light-irradiated, and the oxygen-inhibited layer was either retained or removed with ethanol. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The dentin bond strengths of specimens with and without the oxygen-inhibited layer were measured. For all surfaces, the value of the estimated surface tension component was relatively constant at 35.5-39.8 mJ m(-2) . The value of the , Lewis acid component increased slightly when the oxygen-inhibited layer was removed, whereas that of the , Lewis base component decreased significantly. The bond strengths of the self-etch adhesives were significantly lower in specimens without an oxygen-inhibited layer (13.2-13.6 MPa) than in those with an oxygen-inhibited layer (17.5-18.4 MPa). These results indicate that the presence of an oxygen-inhibited layer in single-step self-etch adhesives with advanced photoinitiators promotes higher dentin bond strength. PMID:21896057

  5. Comparative study of the bond strength of self-etch adhesive systems with different pHs applied to enamel and dentine

    Rubens Côrte Real de Carvalho

    2008-01-01

    Full Text Available Objective: To evaluate whether the pH of the primer is capable of influencing the bond strength of three self-etching adhesive systems to enamel and dentin. Methods: Forty enamel surfaces and 40 dentin surfaces were used, divided into eight groups (n=10 according to the adhesive system (Single Bond, ClearfilSE, AdheSE, Adper Prompt L-Pop. A 3 mm matrix was used to delimit the area restored with composite resin Z250. The test specimens were stored in distilled water at 37ºC for 24 hours and submitted to mechanical shear testing.Results: The ANOVA and Tukey statistical tests showed that there was no statistical difference among the groups in which the adhesivesystems Single Bond (control and Clearfil SE Bond were used and among the groups in which the AdheSE and Adper Prompt L-Pop systemswere used, both with statistical difference when compared with the Single Bond and Clearfil SE Bond groups. There was no statisticallysignificant difference between the bond strength values obtained, when the same adhesive systems were compared with regard to thesubstrates (enamel and dentin. The increased acidity of the self-etch adhesive systems was not capable of increasing the bond strengthvalues. Conclusion: The increasing of self-etch acidity of adhesive systems was not capable to increase the band strenght values. In the comparison between the same adhesive system in enamel or dentin, all adhesive presented similar performance, irrespective of the substrate used.

  6. Effect of desensitizing agents on the microtensile bond strength of two-step etch-and-rinse adhesives to dentin.

    Cortiano, Fernanda M; Rached, Rodrigo N; Mazur, Rui F; Vieira, Sergio; Freire, Andrea; de Souza, Evelise M

    2016-06-01

    Desensitizers can be used to control postoperative sensitivity in adhesive restorations. The aim of this study was to evaluate the effect of desensitizing agents on the bond strength of two-step etch-and-rinse adhesive systems to dentin. Forty-two human molars were sectioned to obtain 3-mm-thick dentin discs. The discs were divided into three groups (n = 14 in each) - no-treatment control group (CT), and oxalic acid [BisBlock (BB)] and calcium phosphate [Desensibilize Nano-P (NP)] desensitizers - before the application of two adhesive systems [Adper Single Bond Plus (SB) and One-Step Plus (OSP)]. A nanoparticle composite resin was used to create a 3-mm-thick build-up. The specimens were stored in distilled water for 24 h before a microtensile bond-strength test was performed. The failure modes were determined using a stereomicroscope at 100 × magnification. Specimens were sectioned perpendicular to the interface for scanning electron microscopy analyses. The CT-SB group exhibited the highest bond strength, differing significantly from BB-SB and BB-OSP groups. Mixed failures were prevalent for all groups. Scanning electron microscopy revealed a continuous hybrid layer and resin tags in all groups. Dentin bond strength of etch-and-rinse adhesive systems was reduced by an oxalic acid desensitizer but was not affected by a calcium phosphate-containing desensitizer. PMID:27038226

  7. The Influence of No-Primer Adhesives and Anchor Pylons Bracket Bases on Shear Bond Strength of Orthodontic Brackets

    Andrea Scribante

    2013-01-01

    Full Text Available Objective. The aim of this study was to compare the shear bond strength (SBS and adhesive remnant index (ARI scores of no-primer adhesives tested with two different bracket bases. Materials and Methods. 120 bovine permanent mandibular incisors were divided into 6 groups of 20 specimens. Two brackets (ODP with different bracket bases (anchor pylons and 80-gauge mesh were bonded to the teeth using a conventional adhesive (Transbond XT and two different no-primer adhesive (Ortho Cem; Heliosit systems. Groups were tested using an instron universal testing machine. SBS values were recorded. ARI scores were measured. SEM microphotographs were taken to evaluate the pattern of bracket bases. Statistical analysis was performed. ANOVA and Tukey tests were carried out for SBS values, whereas a chi-squared test was applied for ARI scores. Results. Highest bond strength values were reported with Transbond XT (with both pad designs, Ortho Cem bonded on anchor pylons and Heliosit on 80-gauge mesh. A higher frequency of ARI score of “3” was reported for Transbond XT groups. Other groups showed a higher frequency of ARI score “2” and “1.” Conclusion. Transbond XT showed the highest shear bond strength values with both pad designs.

  8. Analytical model of asymmetrical Mixed-Mode Bending test of adhesively bonded GFRP joint

    M. Ševčík

    2015-10-01

    Full Text Available This paper presents new analytical model of asymmetric mixed-mode bending (MMB specimen of adhesively bonded pultruded GFRP joints. An easily applicable relationship for the calculation of the strain energy release rate of the asymmetric MMB specimens is proposed based on the beam theory. The model is capable to analyze stacking sequence as well as various crack propagation paths. In the paper the effect of the various fiber bridging length and different crack propagation paths is analyzed analytically and supported by experimental results. The methodology and results presented in this paper could be utilized for the design of both joint geometry and lay-up of the laminates constituting the joint or for the prediction of the fracture behavior of such structures.

  9. Thermographic testing of adhesive bonded joints in car body construction; Thermografische Pruefung von Fuegeverbindungen im Karosseriebau

    Siemer, Ulrike [Volkswagen AG, Wolfsburg (Germany)

    2011-07-01

    In the automotive industry, non-destructive testing (NDT) has a great capability to improve the part quality and to make production processes more efficient. Non-destructive testing techniques that are suitable for the inline quality control of conventional joining techniques (e.g. spot or laser welding) in body-in-white structures are presented. The ultrasound excited thermography has proved its general feasibility for the evaluation of adhesive bonded joints. This application is currently under investigation at Volkswagen. Current results of ongoing tests with scopes and constraints of the technique are shown. Furthermore, an outlook to new applications developed for future body structure concepts will be given. Challenges for testing new materials and joining technologies will be discussed. Another important aspect of this paper is the need to qualify non-destructive testing procedures for the implementation in automotive production processes. An approach how to prove their feasibility is presented. (orig.)

  10. Effect of Bioactive Glass air Abrasion on Shear Bond Strength of Two Adhesive Resins to Decalcified Enamel.

    Alireza Eshghi

    2014-12-01

    Full Text Available Bioactive glass air abrasion is a conservative technique to remove initial decalcified tissue and caries. This study examined the shear bond strength of composite resin to sound and decalcified enamel air-abraded by bioactive glass (BAG or alumina using etch-and-rinse and self-etch adhesives.Forty-eight permanent molars were root-amputated and sectioned mesiodistally. The obtained 96 specimens were mounted in acrylic resin; the buccal and lingual surfaces remained exposed. A demineralizing solution was used to decalcify half the specimens. Both sound and decalcified specimens were divided into two groups of alumina and bioactive glass air abrasion. In each group, the specimens were subdivided into two subgroups of Clearfil SE Bond or OptiBond FL adhesives (n=12. Composite resin cylinders were bonded on enamel surfaces cured and underwent thermocycling. The specimens were tested for shear bond strength. Data were analyzed using SPSS 16.0 and three-way ANOVA (α=0.05. Similar to the experimental groups, the enamel surface of one specimen underwent SEM evaluation.No significant differences were observed in composite resin bond strength subsequent to alumina or bioactive glass air abrasion preparation techniques (P=0.987. There were no statistically significant differences between the bond strength of etch-and-rinse and self-etch adhesive groups (P=1. Also, decalcified or intact enamel groups had no significant difference (P=0.918. However, SEM analysis showed much less enamel irregularities with BAG air abrasion compared to alumina air abrasion.Under the limitations of this study, preparation of both intact and decalcified enamel surfaces with bioactive glass air abrasion results in similar bond strength of composite resin in comparison with alumina air abrasion using etch-&-rinse or self-etch adhesives.

  11. Adhesive-Bonded Composite Joint Analysis with Delaminated Surface Ply Using Strain-Energy Release Rate

    Chadegani, Alireza; Yang, Chihdar; Smeltzer, Stanley S. III

    2012-01-01

    This paper presents an analytical model to determine the strain energy release rate due to an interlaminar crack of the surface ply in adhesively bonded composite joints subjected to axial tension. Single-lap shear-joint standard test specimen geometry with thick bondline is followed for model development. The field equations are formulated by using the first-order shear-deformation theory in laminated plates together with kinematics relations and force equilibrium conditions. The stress distributions for the adherends and adhesive are determined after the appropriate boundary and loading conditions are applied and the equations for the field displacements are solved. The system of second-order differential equations is solved to using the symbolic computation tool Maple 9.52 to provide displacements fields. The equivalent forces at the tip of the prescribed interlaminar crack are obtained based on interlaminar stress distributions. The strain energy release rate of the crack is then determined by using the crack closure method. Finite element analyses using the J integral as well as the crack closure method are performed to verify the developed analytical model. It has been shown that the results using the analytical method correlate well with the results from the finite element analyses. An attempt is made to predict the failure loads of the joints based on limited test data from the literature. The effectiveness of the inclusion of bondline thickness is justified when compared with the results obtained from the previous model in which a thin bondline and uniform adhesive stresses through the bondline thickness are assumed.

  12. Influence of different adhesive systems on bond strength of carbon fiber posts used to restore endodontically treated teeth

    Lorena dos Santos Silva

    2013-12-01

    Full Text Available The aim of this study was to evaluate the influence of three adhesive systems on resinous bonding of carbon fiber posts on roots of endodontically treated bovine incisors. Thirty bovine lower incisors with similar dimensions were selected for this study. The roots were endodontically treated and subsequently prepared for post cementation. The posts were treated with adhesive systems Scotchbond MultiPurpose Plus – 3M chemical cure (Group I, light cure (Group II and dual cure (Group III. Carbon fiber posts were adjusted to 8mm and cemented in the canal with resinous dual cement RelyX ARC – 3M. Those were taken to Universal Essay Machine for the push-out shear bond strength test. Analysis of the results were made with 2-Way ANOVA and post-hoc with Tukey’s test (p<0.05. The groups were statistically different. The chemical cure adhesive system (Group I showed highest values of resistance to push-out, both at all thirds as well as in total average (24.77 MPa, followed by light cure adhesive (Group II, 22.26 MPa, and dual cure (Group III, 18.38 MPa. Scothbond Multi-Purpose Plus – 3M adhesive system presented highest shear bond strength on resinous cementation of carbon posts to root dentin, and therefore is the first choice among the materials presented in this study.

  13. Preparation and properties of a starch-based wood adhesive with high bonding strength and water resistance.

    Zhang, Yanhua; Ding, Longlong; Gu, Jiyou; Tan, Haiyan; Zhu, Libin

    2015-01-22

    A Highly efficient method was developed for preparing starch-based wood adhesives with high performance, using H2O2, a silane coupling agent and an olefin monomer as an oxidant, cross-linking agent and comonomer, respectively. The effects of various parameters on the shear adhesive strength were investigated in the dry state (DS) and wet state (WS). The results indicated that the bonding strength of starch-based wood adhesives could reach 7.88 MPa in dry state and 4.09 MPa in wet state. The oxidation could reduce the content of the hydroxyl transforming into carboxyl and aldehyde groups, and the graft copolymerization enhanced the thermal stability, which improved the bonding strength and water resistance. The starch-based adhesive and the fractures in the bonded joints were analyzed via Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The improved properties were attributed to the modified of microstructure of the graft-copolymerized starch-based adhesive. PMID:25439864

  14. Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires

    Chen, Weifeng; He, Yan; Ouyang, Gang, E-mail: gangouy@hunnu.edu.cn [Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Synergetic Innovation Center for Quantum Effects and Applications(SICQEA), Hunan Normal University, Changsha 410081 (China); Sun, Changqing [School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

    2016-01-15

    The thermal conductivity of Si/Ge core-shell nanowires (CSNWs) is investigated on the basis of atomic-bond-relaxation consideration and continuum mechanics. An analytical model is developed to clarify the interface bond relaxation of Si/Ge CSNWs. It is found that the thermal conductivity of Si core can be modulated through covering with Ge epitaxial layers. The change of thermal conductivity in Si/Ge CSNWs should be attributed to the surface relaxation and interface mismatch between inner Si nanowire and outer Ge epitaxial layer. Our results are in well agreement with the experimental measurements and simulations, suggesting that the presented method provides a fundamental insight of the thermal conductivity of CSNWs from the atomistic origin.

  15. Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires

    Weifeng Chen

    2016-01-01

    Full Text Available The thermal conductivity of Si/Ge core-shell nanowires (CSNWs is investigated on the basis of atomic-bond-relaxation consideration and continuum mechanics. An analytical model is developed to clarify the interface bond relaxation of Si/Ge CSNWs. It is found that the thermal conductivity of Si core can be modulated through covering with Ge epitaxial layers. The change of thermal conductivity in Si/Ge CSNWs should be attributed to the surface relaxation and interface mismatch between inner Si nanowire and outer Ge epitaxial layer. Our results are in well agreement with the experimental measurements and simulations, suggesting that the presented method provides a fundamental insight of the thermal conductivity of CSNWs from the atomistic origin.

  16. Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires

    The thermal conductivity of Si/Ge core-shell nanowires (CSNWs) is investigated on the basis of atomic-bond-relaxation consideration and continuum mechanics. An analytical model is developed to clarify the interface bond relaxation of Si/Ge CSNWs. It is found that the thermal conductivity of Si core can be modulated through covering with Ge epitaxial layers. The change of thermal conductivity in Si/Ge CSNWs should be attributed to the surface relaxation and interface mismatch between inner Si nanowire and outer Ge epitaxial layer. Our results are in well agreement with the experimental measurements and simulations, suggesting that the presented method provides a fundamental insight of the thermal conductivity of CSNWs from the atomistic origin

  17. Loading and fracture response of CFRP-to-steel adhesively bonded joints with thick adherents – Part I: Experiments

    Anyfantis, Konstantinos; Tsouvalis, Nicholas G.

    2013-01-01

    There is a gap in the existing standardized testing procedures (ASTM and ISO) for evaluating the stiffness and strength of composite-to-metal adhesively bonded joints. Thus, there is much effort made in this field towards understanding the impact of the geometric parameters to the loading and fra...

  18. Bond Strength of a Bisphenol-A-Free Fissure Sealant With and Without Adhesive Layer under Conditions of Saliva Contamination.

    Mesquita-Guimarães, Késsia Suênia Fidelis de; Sabbatini, Iliana Ferraz; Almeida, Cintia Guimarães de; Galo, Rodrigo; Nelson-Filho, Paulo; Borsatto, Maria Cristina

    2016-01-01

    Dental sealants are important for prevention of carious lesions, if they have good shear strength. The aim of this study was to evaluate the shear bond strength (SBS) of two sealants to saliva-contaminated and non-contaminated enamel with and without an intermediate adhesive layer underneath the sealant. Ninety flat enamel surfaces from human third molars were randomly assigned to 6 groups (n=15): F (control): Fluroshield(tm) sealant; EWB (control): Embrace(tm) WetBond(tm); SB/F: Single Bond adhesive system + F; SB/EWB, s-SB/F and s-SB/EWB. In the s-SB/F and s-SB/EWB groups, the acid-etched enamel was contaminated with 0.01 mL of fresh human saliva for 20 s. Sealant cylinders were bonded to enamel surface with and without an intermediate adhesive system layer. The shear tests were performed using a universal testing machine (0.5 mm/min). Data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests (α=0.05). F presented higher mean SBS than EWB in all experimental conditions. The lowest SBS mean was obtained for EWB on contaminated enamel (padhesive system layer should be used prior to sealant placement, in both dry and saliva-contaminated enamel. F had the best performance in all experimental conditions. EWB sealant showed very low results, but an adhesive layer underneath the sealant increased its SBS even after salivary contamination. PMID:27224565

  19. Dry adhesive bonding of nanoporous inorganic membranes to microfluidic devices using the OSTE(+) dual-cure polymer

    We present two transfer bonding schemes for incorporating fragile nanoporous inorganic membranes into microdevices. Such membranes are finding increasing use in microfluidics, due to their precisely controllable nanostructure. Both schemes rely on a novel dual-cure dry adhesive bonding method, enabled by a new polymer formulation: OSTE(+), which can form bonds at room temperature. OSTE(+) is a novel dual-cure ternary monomer system containing epoxy. After the first cure, the OSTE(+) is soft and suitable for bonding, while during the second cure it stiffens and obtains a Young’s modulus of 1.2 GPa. The ability of the epoxy to react with almost any dry surface provides a very versatile fabrication method. We demonstrate the transfer bonding of porous silicon and porous alumina membranes to polymeric microfluidic chips molded into OSTE(+), and of porous alumina membranes to microstructured silicon wafers, by using the OSTE(+) as a thin bonding layer. We discuss the OSTE(+) dual-cure mechanism, describe the device fabrication and evaluate the bond strength and membrane flow properties after bonding. The membranes bonded to OSTE(+) chips delaminate at 520 kPa, and the membranes bonded to silicon delaminate at 750 kPa, well above typical maximum pressures applied to microfluidic circuits. Furthermore, no change in the membrane flow resistance was observed after bonding. (paper)

  20. Chemical adhesion rather than mechanical retention enhances resin bond durability of a dental glass-ceramic with leucite crystallites

    This study aims to evaluate the effect of chemical adhesion by a silane coupler and mechanical retention by hydrofluoric acid (HFA) etching on the bond durability of resin to a dental glass ceramic with leucite crystallites. Half of the ceramic plates were etched with 4.8% HFA (HFA group) for 60 s, and the other half were not treated (NoHFA group). The scale of their surface roughness and rough area was measured by a 3D laser scanning microscope. These plates then received one of the following two bond procedures to form four bond test groups: HFA/cement, NoHFA/cement, HFA/silane/cement and NoHFA/silane/cement. The associated micro-shear bond strength and bond failure modes were tested after 0 and 30 000 thermal water bath cycles. Four different silane/cement systems (Monobond S/Variolink II, GC Ceramic Primer/Linkmax HV, Clearfil Ceramic Primer/Clearfil Esthetic Cement and Porcelain Liner M/SuperBond C and B) were used. The data for each silane/cement system were analyzed by three-way ANOVA. HFA treatment significantly increased the surface Ra and Ry values and the rough area of the ceramic plates compared with NoHFA treatment. After 30 000 thermal water bath cycles, the bond strength of all the test groups except the HFA/Linkmax HV group was significantly reduced, while the HFA/Linkmax HV group showed only adhesive interface failure. The other HFA/cement groups and all NoHFA/cement groups lost bond strength completely, and all NoHFA/silane/cement groups with chemical adhesion had significantly higher bond strength and more ceramic cohesive failures than the respective HFA/cement groups with mechanical retention. The result of the HFA/silane/cement groups with both chemical adhesion and mechanical retention revealed that HFA treatment could enhance the bond durability of resin/silanized glass ceramics, which might result from the increase of the chemical adhesion area on the ceramic rough surface and subsequently reduced degradation speed of the silane coupler

  1. Chemical adhesion rather than mechanical retention enhances resin bond durability of a dental glass-ceramic with leucite crystallites

    Meng, X F [Department of Prosthodontics, The Stomatological Hospital Affiliated Medical School, Nanjing University, Nanjing 210008 (China); Yoshida, K [Division of Applied Prosthodontics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588 (Japan); Gu, N, E-mail: mengsoar@nju.edu.c [Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096 (China)

    2010-08-01

    This study aims to evaluate the effect of chemical adhesion by a silane coupler and mechanical retention by hydrofluoric acid (HFA) etching on the bond durability of resin to a dental glass ceramic with leucite crystallites. Half of the ceramic plates were etched with 4.8% HFA (HFA group) for 60 s, and the other half were not treated (NoHFA group). The scale of their surface roughness and rough area was measured by a 3D laser scanning microscope. These plates then received one of the following two bond procedures to form four bond test groups: HFA/cement, NoHFA/cement, HFA/silane/cement and NoHFA/silane/cement. The associated micro-shear bond strength and bond failure modes were tested after 0 and 30 000 thermal water bath cycles. Four different silane/cement systems (Monobond S/Variolink II, GC Ceramic Primer/Linkmax HV, Clearfil Ceramic Primer/Clearfil Esthetic Cement and Porcelain Liner M/SuperBond C and B) were used. The data for each silane/cement system were analyzed by three-way ANOVA. HFA treatment significantly increased the surface R{sub a} and R{sub y} values and the rough area of the ceramic plates compared with NoHFA treatment. After 30 000 thermal water bath cycles, the bond strength of all the test groups except the HFA/Linkmax HV group was significantly reduced, while the HFA/Linkmax HV group showed only adhesive interface failure. The other HFA/cement groups and all NoHFA/cement groups lost bond strength completely, and all NoHFA/silane/cement groups with chemical adhesion had significantly higher bond strength and more ceramic cohesive failures than the respective HFA/cement groups with mechanical retention. The result of the HFA/silane/cement groups with both chemical adhesion and mechanical retention revealed that HFA treatment could enhance the bond durability of resin/silanized glass ceramics, which might result from the increase of the chemical adhesion area on the ceramic rough surface and subsequently reduced degradation speed of the silane

  2. Distribution of calcium ions at the interface between resin bonding materials and tooth dentin. Use of commercially available adhesive systems.

    Hanaizumi, Y; Maeda, T; Takano, Y

    1998-01-01

    It has been proposed that calcium ions play a key role in chemical (chelate) binding between the adhesive resin and dentin surface. However, no data is available concerning how calcium ions are distributed at the binding sites. The aim of this study is to demonstrate calcium ions at the resin-dentin interface by means of X-ray microanalysis and calcium ion-sensitive histochemical staining. The dentin surface in human teeth was ground by use of 240 grit silicon carbide abrasive paper under running water and treated with the dentin-primer and adhesive resin in Clearfil Liner Bond System or IMPERVA Bond System according to the manufacturer's instructions. After removing dentin matrix and isolating adhesive resin by the KOH-digestion method, one half of the samples were processed for scanning electron microscopy. The rest were embedded in Epon 812 and processed either for glyoxal bis (2-hydroxyanil) (GBHA) staining or transmission electron microscopy combined with X-ray microanalysis. Transmission electron microscopy revealed Ca-phosphate deposits at the bottom of the resin-impregnated layer. The adhesive resin above the resin-impregnated layer was amorphous and showed no precipitates of Ca-phosphate. GBHA displayed intense calcium reactions throughout the resin-impregnated layer and also moderate ones in the 10 microns (Clearfil Liner Bond System) or 30 microns (IMPERVA Bonding System) thick boundary zone of the adhesive resin as well as in the resin tags. These data are the first to offer a distinct localization of calcium ions within the adhesive resin at the dentin-resin interface. PMID:9800373

  3. Effect of repeated use on dentin bond strength of two adhesive systems: All-in-one and one-bottle

    Shafiei Fershteh

    2009-01-01

    Full Text Available Aims: To compare the effects of repeated use of two one-bottle adhesives with that of two all- in- one adhesives (with acetone solvent on bond strength to dentin. Materials and Methods: A flat dentin surface was prepared on 120 bovine incisors using 600- grit abrasive pape. The teeth were randomly assigned into 12 equal groups. The four adhesive systems [Prime and Bond NT (P&B NT, One-Step Plus (OS, iBond (iB, and G-Bond (GB] were used at baseline, after the lid of the container had been opened 30 times, and after it had been opened 60 times. Before each use of the adhesives, the lids of the containers were left open for 1 min. The resin composites were applied on the dentin in a cylindrical split mold. After thermocycling, shear bond strength test was performed with a universal testing machine at 1 mm/min. We used Kruskal-Wallis and Dunn tests for statistical analysis. Results: There was no statistically significant difference among bond strength (MPa of the groups of P&B NT (31.9 ± 4.6, 31.8 ± 6.5, 26.1 ± 6.7 and OS (33.2 ± 5.1, 30.9 ± 7, 29.3 ± 5.9, respectively (P > 0.05. The mean of the bond strength of iB and GB after 60 times (15.3 ± 4.1 and 12.2 ± 3.9, respectively was significantly lower than that of iB and GB at baseline (23.5 ± 4.8 and 22.2 ± 4.5, respectively (P < 0.05. Conclusions: Repeated use (60 times of the all-in-one adhesive led to a decline in the dentin bond strength. To avoid this problem it would be advisable to have containers with smaller amounts of adhesive or perhaps those with only a singe dose.

  4. Effect of Thermocycling, Degree of Conversion, and Cavity Configuration on the Bonding Effectiveness of All-in-One Adhesives.

    El-Damanhoury, H M; Gaintantzopoulou, M

    2015-01-01

    The aim of this study was to compare five all-in-one bonding agents with respect to microleakage, microtensile bond strength (μTBS), degree of conversion (DC) and the impact of cavity configuration. The materials tested were Adper Easy Bond, Clearfil S3 Bond, iBond, Optibond All-in-One, Xeno IV, and Adper Single Bond Plus as a control. The DC of each adhesive was measured on the surfaces of dentin discs (n=5) by attenuated total reflectance Fourier transform infrared spectroscopy. One hundred and forty-four extracted human molars were randomly divided and assigned to one of the five tested adhesives and the control group. The μTBS to dentin was measured on flat occlusal dentin with and without thermocycling and to the gingival floor dentin of class II cavities (n=8). All specimens were restored with Filtek Z250 resin composite. Class II samples were immersed in a 5% methylene blue dye solution for 24 hours, and microleakage was examined under a stereomicroscope. Micromorphological analysis of demineralized/deproteinized specimens was done using scanning electron microscopy. The DC and microleakage data were statistically analyzed by one-way analysis of variance (ANOVA) and μTBS data by two-way ANOVA followed by a Bonferroni multiple comparison post hoc test (α=0.05) and Weibull-distribution survival analysis. The relation between different variables and μTBS and microleakage was tested by the Pearson correlation coefficient and regression statistics. A moderate direct relation between DC and μTBS durability was found for all the adhesives tested. Significant wide variations exist among the results obtained for single-bottle adhesives tested regarding their μTBS and microleakage. Some of the all-in-one materials tested have shown significantly inferior results under a high C-factor or after aging. The use of these materials should be carefully considered. PMID:25748210

  5. The shear bond strength of MTA with three different types of adhesive systems: An in vitro study

    Tyagi, Nimish; Chaman, Chandrakar; Tyagi, Shashi Prabha; Singh, Udai Pratap; Sharma, Apoorv

    2016-01-01

    Aim: To evaluate the shear bond strength of MTA with three different types of adhesive systems- self-adhering flowable composite, etch and rinse adhesive system and self etch adhesive system. Methodology: MTA specimens (n = 60) were prepared using cylindrical acrylic blocks, having a central cavity with 4 mm diameter and 2 mm depth. MTA was mixed and placed in the prepared cavity, and was covered with a moist cotton pellet and temporary filling material. The specimens were divided into 3 groups which were further divided into 2 sub-groups (45 Minutes and 24 hours). After the application of bonding agents composite resin was placed over the MTA surface. The specimens were tested for shear bond strength and readings were statically analyzed. Result: After 24 hrs the mean value of etch and rinse group was significantly higher than self etch and the self adhering composite groups. Among the 45 minutes groups there were no significant difference. Conclusion: In single visit after 45 minutes self adhering flowable can be used successfully as a final restorative material in place of conventional flowable composite without using any alternative adhesive system over MTA. PMID:27099417

  6. Adhesive Bonding and Self-Curing Characteristics of α-Starch Based Composite Binder for Green Sand Mould/Core

    Xia ZHOU; Jinzong YANG; Guohui QU

    2004-01-01

    Interactions between different components in α-starch based composite binder for green sand mould/core were investigated by using XRD, IR spectra, 1H NMR spectra and SEM. Several adhesive hardening structures and theories of the binder at room temperature were proposed according to the interactions between various compositions. Thus,the reasons for the binder to have excellent combination properties and unique adhesive bonding and self-curing characteristics were explained by these theories successfully. And the theories are of great directive importance to design and development of composite binder for green sand mould/core.

  7. Effect of dimethyl sulfoxide on bond durability of fiber posts cemented with etch-and-rinse adhesives

    Shafiei, Fereshteh; Sarafraz, Zahra

    2016-01-01

    PURPOSE This study was undertaken to investigate whether use of an adhesive penetration enhancer, dimethyl sulfoxide (DMSO), improves bond stability of fiber posts to root dentin using two two-step etch-and-rinse resin cements. MATERIALS AND METHODS Forty human maxillary central incisor roots were randomly divided into 4 groups after endodontic treatment and post space preparation, based on the fiber post/cement used with and without DMSO pretreatment. Acid-etched root dentin was treated with 5% DMSO aqueous solution for 60 seconds or with distilled water (control) prior to the application of Excite DSC/Variolink II or One-Step Plus/Duo-link for post cementation. After micro-slicing the bonded root dentin, push-out bond strength (P-OBS) test was performed immediately or after 1-year of water storage in each group. Data were analyzed using three-way ANOVA and Student's t-test (α=.05). RESULTS A significant effect of time, DMSO treatment, and treatment × time interaction were observed (P.05). CONCLUSION DMSO-wet bonding might be a beneficial method in preserving the stability of resin-dentin bond strength over time when fiber post is cemented with the tested etch-and-rinse adhesive cements.

  8. Effect of Bioactive Glass air Abrasion on Shear Bond Strength of Two Adhesive Resins to Decalcified Enamel

    Alireza Eshghi; Maryam Khoroushi; Alireza Rezvani

    2014-01-01

    Objective: Bioactive glass air abrasion is a conservative technique to remove initial decalcified tissue and caries. This study examined the shear bond strength of composite resin to sound and decalcified enamel air-abraded by bioactive glass (BAG) or alumina using etch-and-rinse and self-etch adhesives. Materials and Methods: Forty-eight permanent molars were root-amputated and sectioned mesiodistally. The obtained 96 specimens were mounted in acrylic resin; the buccal and lingual surfaces r...

  9. Optimisation of industrial production of low-force sensors – adhesive bonding of force-centring ball

    Maeder, Thomas; Jacq, Caroline; Blot, Maxime; Ryser, Peter

    2015-01-01

    This work addresses the issue of attaching the force-centring part (a round ball) to the load cell of a force sensor, a piezoresistive thick-film Wheatstone bridge deposited onto a ceramic cantilever. As the current soldering process requires expensive metallisation steps for both the ball and the cantilever, and subjects the solder pads used for mounting the cantilever to an additional reflow cycle, an alternative adhesive bonding process was developed, allowing both simpler production and t...

  10. In vitro evaluation of influence of salivary contamination on the dentin bond strength of one-bottle adhesive systems

    Nujella B.P Suryakumari

    2011-01-01

    Full Text Available Aim: To evaluate the effect of salivary contamination on the bond strength of one-bottle adhesive systems - (the V generation at various stages during the bonding procedure and to investigate the effect of the contaminant removing treatments on the recovery of bond strengths. Materials and Methods: In this study the V generation one-bottle system - (Adper Single Bond was tested. Fifty caries-free human molars with flat dentin surfaces were randomly divided into five groups of ten teeth each: Group I had 15 second etching with 35% Ortho Phosphoric acid, 15 second rinse and blot dried (Uncontaminated; Group II contaminated and blot dried; Group III contaminated and completely dried; Group IV contaminated, washed, blot dried; Group V contaminated, retched washed, and blot dried. The bonding agent was applied and resin composite (Z-100 3M ESPE was bonded to the treated surfaces using the Teflon mold. The specimens in each group were then subjected to shear bond strength testing in an Instron Universal testing machine at a crosshead speed of 1 mm / minute and the data were subjected to one way ANOVA for comparison among the groups (P<0.05. Results: There was a significant difference between the group that was dried with strong oil-free air after contamination (Group III and the other groups. When the etched surface was contaminated by saliva, there was no statistical difference between the just blot dry, wash, or the re-etching groups (Groups II, IV, V if the dentin surface was kept wet before priming. When the etched dentin surface was dried (Group III the shear bond strength decreased considerably. Conclusion: The bond strengths to the tooth structure of the recent dentin bonding agents are less sensitive to common forms of contamination than assumed. Re-etching without additional mechanical preparation is sufficient to provide or achieve the expected bond strength.

  11. In vitro evaluation of casein phosphopeptide-amorphous calcium phosphate effect on the shear bond strength of dental adhesives to enamel

    Niloofar Shadman

    2015-01-01

    Full Text Available Background: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP is applied for remineralization of early caries lesions or tooth sensitivity conditions and may affect subsequent resin bonding. This in vitro study investigated the effect of CPP-ACP on the shear bond strength of dental adhesives to enamel. Materials and Methods: Sixty extracted human molar teeth were selected and randomly divided into three groups and six subgroups. Buccal or lingual surfaces of teeth were prepared to create a flat enamel surface. Adhesives used were Tetric N-Bond, AdheSE and AdheSE One F. In three subgroups, before applying adhesives, enamel surfaces were treated with Tooth Mousse CPP-ACP for one hour, rinsed and stored in 37°C temperature with 100% humidity. This procedure was repeated for 5 days and then adhesives were applied and Tetric N-Ceram composite was adhered to the enamel. This procedure was also fulfilled for the other three subgroups without CPP-ACP treatment. After 24 hour water storage, samples were tested for shear bond strength test in a universal testing machine. Failure modes were determined by stereomicroscope. Data were analyzed by t-test and one-way analysis of variance with P 0.05. In non-applied CPP-ACP subgroups, there were statistically significant differences among all subgroups. Tetric N-Bond had the highest and AdheSE One F had the lowest shear bond strength. Conclusion: CPP-ACP application reduces the shear bond strength of AdheSE and AdheSE One F to enamel but not Tetric N-Bond.

  12. Effect of Numbers of Load Cycling on the Micro Tensile Bond Strength of Total Etch Adhesives to Dentin

    AR Daneshkazemi

    2013-06-01

    Full Text Available Introduction: Today load cycling is used for similarity of invitro and invivo studies, though different results were reported in different studies. Therefore, this study aimed to investigate the effect of load cycling on micro tensile bond strength of two total etch adhesives to dentin. Methods: Enamel of 48 molar teeth were removed to expose the superficial dentin. The teeth were randomly divided into two equal groups, and were restored with Single bond (SB, ExciTE and Synergy composite. Then the teeth of each group were divided to 4 equal sub groups. Moreover, load cycling of 0, 50, 100, 200 k load cycle with 50 newton load was used. In each sub group, 12 hour glass slabs with 1mm2 thickness were made. Then the samples were loaded by Dartec testing machine (Model HC/10 with 1 mm/min cross head speed to make the fracture occur. Data were analyzed by ANOVA, t-test, Bonferroni tests. Results: The most micro tensile bond strength belonged to ExciTE without load cycling and lowest refered to SB with 200 k. There was a significant difference between the groups (p ExciTE= 0.0001, p SB = 0.001. Micro tensile bond strength in SB group was significantly lower than ExciTE (p= 0.001. Moreover, load cycling had negative effect on micro tensile bond strength. Conclusion: By increasing load cycling, micro tensile bond strength of both bondings decreased significantly

  13. Effect of dentin dehydration and composite resin polymerization mode on bond strength of two self-etch adhesives

    Pooran Samimi

    2016-01-01

    Full Text Available Background: Dual-cured composite resins are similar to self-cured composite resins in some of their clinical applications due to inadequate irradiation, lack of irradiation, or delayed irradiation. Therefore, incompatibility with self-etch adhesives (SEAs should be taken into account with their use. On the other, the extent of dentin dehydration has a great role in the quality of adhesion of these resin materials to dentin. The aim of this study was to investigate the effect of dentin dehydration and composite resin polymerization mode on bond strength of two SEAs. Materials and Methods: A total of 120 dentinal specimens were prepared from extracted intact third molars. Half of the samples were dehydrated in ethanol with increasing concentrations. Then Clearfil SE Bond (CSEB and Prompt L-Pop (PLP adhesives were applied in the two groups. Cylindrical composite resin specimens were cured using three polymerization modes: (1 Immediate light-curing, (2 delayed light-curing after 20 min, and (3 self-curing. Bond strength was measured using universal testing machine at a crosshead speed of 1 mm/min. Data were analyzed with two-way ANOVA and Duncan post hoc tests. Statistical significance was defined at P 0.05. PLP showed significant differences between subgroups with the lowest bond strength in hydrated dentin with delayed light-curing and self-cured mode of polymerization. Conclusion: Within the limitations of this study, a delay in composite resin light-curing or using chemically cured composite resin had a deleterious effect on dentin bond strength of single-step SEAs used in the study.

  14. The effect of oxalate desensitizers on the microleakage of resin composite restorations bonded by etch and rinse adhesive systems.

    Shafiei, Fereshteh; Motamedi, Mehran; Alavi, Ali Asghar; Namvar, Babak

    2010-01-01

    This in vitro study evaluated the effect of an oxalate desensitizer (OX) on the marginal microleakage of resin composite restorations bonded by two three-step and two two-step etch and rinse adhesives. Class V cavities were prepared on the buccal surfaces of 126 extracted premolars at the cementoenamel junction and randomly divided into nine groups of 14 each. In the control groups (1-4), four adhesives were applied, respectively, including Adper Scotchbond Multi-Purpose (SBMP), Optibond FL (OBFL), One-Step Plus (OS) and Excite (EX). In the experimental groups (5-8), the same adhesives, in combination with OX (BisBlock), were applied. And, in one group, OX was applied without any adhesive, as the negative control group (9). All the groups were restored with a resin composite. After 24 hours of storage in distilled water and thermocycling, the samples were placed in 1% methylene blue dye solution. The dye penetration was evaluated using a stereomicroscope. The data were analyzed using non-parametric tests. The OX application, in combination with OBFL and EX, resulted in significantly increasing microleakage at the gingival margins (p 0.05). At the occlusal margins, no significant difference in microleakage was observed after OX application for each of four adhesives (p > 0.05). PMID:21180008

  15. Crystallographic Evidence for Direct Metal-Metal Bonding in a Stable Open-Shell La2 @Ih -C80 Derivative.

    Bao, Lipiao; Chen, Muqing; Pan, Changwang; Yamaguchi, Takahisa; Kato, Tatsuhisa; Olmstead, Marilyn M; Balch, Alan L; Akasaka, Takeshi; Lu, Xing

    2016-03-18

    Endohedral metallofullerenes (EMFs) have novel structures and properties that are closely associated with the internal metallic species. Benzyl radical additions have been previously shown to form closed-shell adducts by attaching an odd number of addends to open-shell EMFs (such as Sc3 C2 @Ih -C80 ) whereas an even number of groups are added to closed-shell EMFs (for example Sc3 N@Ih -C80 ). Herein we report that benzyl radical addition to the closed-shell La2 @Ih -C80 forms a stable, open-shell monoadduct instead of the anticipated closed-shell bisadduct. Single-crystal X-ray diffraction results show the formation of a stable radical species. In this species, the La-La distance is comparable to the theoretical value of a La-La covalent bond and is shorter than reported values for other La2 @Ih -C80 derivatives, providing unambiguous evidence for the formation of direct La-La bond. PMID:26918907

  16. Shear bond strength and SEM morphology evaluation of different dental adhesives to enamel prepared with ER:YAG laser

    Patrícia T Pires

    2013-01-01

    Full Text Available Context: Early observations of enamel surfaces prepared by erbium lasers motivated clinicians to use laser as an alternative to chemical etching. Aims: Evaluate shear bond strength (SBS values of different dental adhesives on Erbium:Yttrium Aluminum Garnet (Er:YAG laser prepared enamel and to evaluate possible etching patterns correlations between dental adhesives and SBS values. Subjects and Methods: One hundred bovine incisors were randomly assigned to SBS tests on enamel (n = 15 and to enamel morphology analysis ( n = 5 after Er:YAG laser preparation as follows: Group I - 37% phosphoric acid (PA+ ExciTE® ; Group II - ExciTE® ; Group III - AdheSE® self-etching; Group IV - FuturaBond® no-rinse. NR; Group V - Xeno® V. Teeth were treated with the adhesive systems and subjected to thermal cycling. SBS were performed in a universal testing machine at 5 mm/min. Statistical Analysis Used: One-way ANOVA and post-hoc tests (p < 0.05. For the morphology evaluation, specimens were immersed in Ethylenediamine tetraacetic acid (EDTA and the etching pattern analyzed under Scanning Electron Microscope (SEM. Results: Mean bond strengths were Group I - 47.17 ± 1.61 MPa (type I etching pattern; Group II - 32.56 ± 1.64 MPa, Group III - 29.10 ± 1.34 MPa, Group IV - 23.32 ± 1.53 MPa (type III etching pattern; Group V - 24.43 MPa ± 1.55 (type II etching pattern. Conclusions: Different adhesive systems yielded significantly different SBSs. Acid etching significantly increased the adhesion in laser treated enamel. No differences in SBS values were obtained between AdheSE® and ExciTE® without condition with PA. FuturaBond® NR and Xeno® V showed similar SBS, which was lower in comparison to the others adhesives. No correlation between enamel surface morphology and SBS values was observed, except when PA was used.

  17. Influence of caries infiltrant contamination on shear bond strength of different adhesives to dentin

    Jia, Liuhe; Stawarczyk, Bogna; Schmidlin, Patrick R; Attin, Thomas; Wiegand, Annette

    2013-01-01

    OBJECTIVES: To analyze whether the contamination with a caries infiltrant system impairs the adhesive performance of etch-and-rinse and self-etching adhesives on dentin. MATERIALS AND METHODS: Dentin contamination with the caries infiltrant system (Icon, DMG) was simulated by applying either hydrochloric acid (15 % HCl, Icon Etch, 15 s), the resin infiltrant (Icon infiltrant, 4 min), or both prior to the application of the respective adhesives (each group n = 10). In the control groups, th...

  18. Fourier transform infrared photoacoustic spectroscopy study of physicochemical interaction between human dentin and etch-&-rinse adhesives in a simulated moist bond technique

    Ubaldini, Adriana L M; Baesso, Mauro L; Sehn, Elizandra;

    2012-01-01

    systems: (a) 2-hydroxyethylmethacrylate (HEMA) and 4-methacryloxyethyl trimellitate anhydrate (4-META), and (b) HEMA. The Fourier transform infrared photoacoustic spectroscopy was performed before and after dentin treatment with 37% phosphoric acid, with adhesive systems and also for the adhesive systems......The purpose of this study was to provide the physicochemical interactions at the interfaces between two commercial etch-&-rinse adhesives and human dentin in a simulated moist bond technique. Six dentin specimens were divided into two groups (n=3) according to the use of two different adhesive...... alone. Acid-conditioning resulted in a decalcification pattern. Adhesive treated spectra subtraction suggested the occurrence of chemical bonding to dentin expressed through modifications of the OH stretching peak (3340 cm(-1)) and symmetric CH stretching (2900 cm(-1)) for both adhesives spectra; a...

  19. Modelling the Fracture Behaviour of Adhesively-Bonded Joints as a Function of Test Rate - A Rate Dependent CZM is Required to Predict the Full Range of Behaviour

    Ivankovic, Alojz; Karac, Aleksandar; Blackman, B.R.K.; et al

    2011-01-01

    Adhesive bonding of lightweight, high-performance materials is regarded as a key enabling technology for the development of vehicles with increased crashworthiness, better fuel economy and reduced exhaust emissions. However, as automotive structures can be exposed to impact events during service, it is necessary to gain a sound understanding of the performance of adhesive joints under different rates of loading. Therefore, characterising the behaviour of adhesive joint...

  20. Shear bond strength evaluation of adhesive and tooth preparation combinations used in reattachment of fractured teeth: An ex-vivo study

    Ramachandruni VamsiKrishna; Koppolu Madhusudhana; Aluru Swaroopkumarreddy; Anumula Lavanya; Chinni Suneelkumar; Govula Kiranmayi

    2015-01-01

    Objectives: The objectives of this study were to evaluate the bond strengths of different adhesive materials, different tooth preparation designs and adhesive tooth preparation combinations to reattach fractured incisor fragments. Materials and Methods: The study sample comprised 48 intact human maxillary central incisors divided into two groups A and B. The incisal third was sectioned with a diamond disc. The teeth in Group A were reattached with bonding agent and in Group B with resin lutin...

  1. Genotoxic evaluation of orthodontic bonding adhesives exposed to electron beam irradiation: an in vitro study

    To evaluate the in vitro genotoxicity of two orthodontic adhesives and to determine the type of cell death they induce on human lymphocytes after exposing to Electron Beam Irradiation. The materials tested were 1. Light cure orthodontic adhesive with conventional primer (Transbond XT3M) and 2. Self cure orthodontic adhesive (Unite, 3M). Cured sterile individual masses were immersed in Phosphate Buffer saline and left at 370℃ for 24 h. Then a volume of 200 μL of the extract medium was mixed with human peripheral blood lymphocyte tested for comet assay by single cell DNA damage assay and apoptosis by DNA diffusion agar assay. The results showed all parameters studied by comet assay were significant (P>0.05). In case of apoptosis, light cure orthodontic adhesive (188.92±55.05) and self cure orthodontic adhesives (255.23±76.43) showed increased diffusion of DNA compared to normal lymphocyte (111.22±8.78). However the level of DNA diffusion was not significantly different between the two adhesives. Light cure orthodontic and self cure orthodontic adhesives were induced apoptosis. Both the adhesives had no significant effect on the percentage of DNA tail and olive tail moment. (author)

  2. Influence of Temporary Cements on the Bond Strength of Self-Adhesive Cement to the Metal Coronal Substrate.

    Peixoto, Raniel Fernandes; De Aguiar, Caio Rocha; Jacob, Eduardo Santana; Macedo, Ana Paula; De Mattos, Maria da Gloria Chiarello; Antunes, Rossana Pereira de Almeida

    2015-01-01

    This research evaluated the influence of temporary cements (eugenol-containing [EC] or eugenol-free [EF]) on the tensile strength of Ni-Cr copings fixed with self-adhesive resin cement to the metal coronal substrate. Thirty-six temporary crowns were divided into 4 groups (n=9) according to the temporary cements: Provy, Dentsply (eugenol-containing), Temp Cem, Vigodent (eugenol-containing), RelyX Temp NE, 3M ESPE (eugenol-free) and Temp Bond NE, Kerr Corp (eugenol-free). After 24 h of temporary cementation, tensile strength tests were performed in a universal testing machine at a crosshead speed of 0.5 mm/min and 1 kN (100 kgf) load cell. Afterwards, the cast metal cores were cleaned by scraping with curettes and air jet. Thirty-six Ni-Cr copings were cemented to the cast metal cores with self-adhesive resin cement (RelyX U200, 3M ESPE). Tensile strength tests were performed again. In the temporary cementation, Temp Bond NE (12.91 ± 2.54) and Temp Cem (12.22 ± 2.96) presented the highest values of tensile strength and were statistically similar to each other (p>0.05). Statistically significant difference (pcementation of Ni-Cr copings with self-adhesive resin cement. In addition, Temp Cem (120.68 ± 48.27) and RelyX Temp NE (103.04 ± 26.09) showed intermediate tensile strength values. In conclusion, the Provy eugenol-containing temporary cement was associated with the highest bond strength among the resin cements when Ni-Cr copings were cemented to cast metal cores. However, the eugenol cannot be considered a determining factor in increased bond strength, since the other tested cements (1 eugenol-containing and 2 eugenol-free) were similar. PMID:26963209

  3. Effect of Adhesive Type on the Shear Bond Strength of Metal Brackets to Two Ceramic Substrates

    Mohammad Sadegh Ahmad Akhoundi

    2014-04-01

    Full Text Available Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin.Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM.The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05. There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected.Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.

  4. Bond Strength of a Novel One Bottle Multi-mode Adhesive to Human Dentin After Six Months of Storage

    Manfroi, Fernanda Borguetti; Marcondes, Maurem Leitão; Somacal, Deise Caren; Borges, Gilberto Antonio; Júnior, Luiz Henrique Burnett; Spohr, Ana Maria

    2016-01-01

    Objective: The aim of the study was to evaluate the microtensile bond strength (µTBS) of Scotchbond Universal to dentin using the etch-and-rinse or the self-etch technique after 24 h and 6 months of storage. Materials and Methods: Flat dentin surfaces were obtained in 24 third molars. The teeth were divided into four groups: G1 – Scotchbond Universal applied in the etch-and-rinse mode; G2 – Scotchbond Universal applied in the self-etch mode; G3 – Scotchbond Multi-Purpose; G4 – Clearfil SE Bond. A block of composite was built on the adhesive area. The tooth/resin sets were cut parallel to the long axis to obtain 40 beams (~0.8 mm2) for each group. Twenty specimens were immediately submitted to the µTBS test, and the remaining 20 were stored in water for 6 months. Failures and the adhesive interface were analyzed by SEM. Results: According to two-way ANOVA, the interaction between adhesive and storage time was significant (p=0.015).The µTBS (MPa) means were the following: 24 h – G1 (39.37±10.82), G2 (31.02±13.76), G3 (35.09±14.03) and G4 (35.84±11.06); 6 months – G1 (36.99±8.78), G2 (40.58±8.07), G3 (32.44±6.07) and G4 (41.75±8.25). Most failures were mixed. Evidence of hybrid layer and numerous resin tags were noted for Scotchbond Universal applied with the etch-and-rinse mode and Scotchbond Multi-Purpose. A thinner hybrid layer and fewer resin tags were noted for Scotchbond Universal applied in the self-etch mode and Clearfil SE Bond. Conclusion: The results indicate that the µTBS for Scotchbond Universal is comparable to the gold-standard adhesives. Scotchbond Universal applied in the self-etch mode and Clearfil SE Bond revealed higher bond stability compared to the etch-and-rinse mode. PMID:27347230

  5. Effect of Adhesive Type on the Shear Bond Strength of Metal Brackets to Two Ceramic Substrates

    Mohammad Sadegh Ahmad Akhoundi; Farzaneh Aghajani; Javad Chalipa; Amir Hooman Sadrhaghighi

    2014-01-01

    Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin.Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting,...

  6. A Fracture-Based Criterion for Debonding Strength of Adhesive-Bonded Double-Strap Steel Joints

    Prawit Santisukpotha

    2012-01-01

    Full Text Available This paper addresses the debonding strength of adhesive-bonded double-strap steel joints. A fracture-based criterion was formulated in terms of a stress singularity parameter, i.e., the stress intensity factor, which governs the magnitude of a singular stress field near the joint ends. No existing crack was assumed. A total of 24 steel joint specimens were tested under constant amplitude fatigue loadings at stress ratio of 0.2 and frequency of 2 Hz. The joint stiffness ratio was slightly less than one to control the maximum adhesive stresses at the joint ends. To detect the debonding, a simple and practical technique was developed. The test results showed that the interfacial failure near the steel/adhesive corner was a dominant failure mode. The failure was brittle and the debonding life was governed by the crack initiation stage. The finite element analysis was employed to calculate the stress intensity factors and investigate the effects of the adhesive layer thickness, lap length and joint stiffness ratio on the debonding strength.

  7. Further Investigation Into the Use of Laser Surface Preparation of Ti-6Al-4V Alloy for Adhesive Bonding

    Palmieri, Frank L.; Crow, Allison; Zetterberg, Anna; Hopkins, John; Wohl, Christopher J.; Connell, John W.; Belcher, Tony; Blohowiak, Kay Y.

    2014-01-01

    Adhesive bonding offers many advantages over mechanical fastening, but requires robust materials and processing methodologies before it can be incorporated in primary structures for aerospace applications. Surface preparation is widely recognized as one of the key steps to producing robust and predictable bonds. This report documents an ongoing investigation of a surface preparation technique based on Nd:YAG laser ablation as a replacement for the chemical etch and/or abrasive processes currently applied to Ti-6Al-4V alloys. Laser ablation imparts both topographical and chemical changes to a surface that can lead to increased bond durability. A laser based process provides an alternative to chemical-immersion, manual abrasion, and grit blast process steps which are expensive, hazardous, environmentally unfriendly, and less precise. In addition, laser ablation is amenable to process automation, which can improve reproducibility to meet quality standards for surface preparation. An update on work involving adhesive property testing, surface characterization, surface stability, and the effect of laser surface treatment on fatigue behavior is presented. Based on the tests conducted, laser surface treatment is a viable replacement for the immersion chemical surface treatment processes. Testing also showed that the fatigue behavior of the Ti-6Al-4V alloy is comparable for surfaces treated with either laser ablation or chemical surface treatment.

  8. Effect of Re-Application of Microbrush on Micro Tensile Bond Strength of an Adhesive to Dentin

    Seied Majid Mosavi Nasab

    2013-02-01

    Full Text Available Background and Aims: Re-application of microbrush may affect the micro tensile bond strength of adhesives to dentin. The aim of this study was to evaluate the effect of re-application of microbrushes on the micro tensile bond strength of an adhesive to dentin.Materials and Methods: Thirty freshly extracted molars teeth were collected and enamel of occlusal surface were removed to expose superficial dentin. Then superficial dentin was etched, washed and partially air dried.According to the times of application of microbrush, teeth were divided into two test groups. In group 1, newmicrobrushs were used, but in group 2, the ones that were already used for twice were included. Ambar dentin bonding agent (FGM/Brazil was applied to the etched dentin with microbrushes according to the manufacturer’s instructions. Then the crown of teeth was built up with LLiss (FGM/Brazil composite resin. The teeth were sectioned in buccolingual direction to obtain 1mm slabs. Then 50 hourglass- shape samples were made from 30 teeth (25 Specimens per group. The microtensile bond strength of the specimens was tested using MTD500 (SD Mechatronik, Germany. The data were statistically analyzed by T-test.Results: The mean values for the microtensile bond strength were 30.49±7.18 and 23.61±9.06 MPa±SD for the first and second groups, respectively. There was significant difference between the groups (P=0.005.Conclusion: Microbrushes should not be used for more than one cavity preparation.

  9. Evaluation of the effect of surface moisture on dentinal tensile bond strength to dentine adhesive: An in vitro study

    Jayaprakash Thumu

    2010-01-01

    Full Text Available Aim : To evaluate the effect of surface moisture on dentinal tensile bond strength. Materials and Methods : Forty freshly extracted caries free, unrestored human mandibular molars were selected. The occlusal surfaces of each tooth were ground to prepare flat dentin surfaces at a depth of 1.5 mm. Following acid etching with 37% phosphoric acid for 15 sec, they were randomly grouped, with ten specimens in each: Group I - Over wet, Group II - Blot dry, Group III- One second dry, Group IV- Over dry. Each group was treated with a single bond adhesive system (3M ESPE as per manufacturer′s instructions. Blocks or cylinders of composite resin were built up using Teflon mould and cured. Tensile bond strengths were tested using Instron universal testing machine. The results were statistically analyzed. Results : The mean tensile bond strength values of group II, Blot dry was highest and statistically significant (P<0.001. Conclusion : After acid etching and rinsing blot drying provided consistently better bond strength.

  10. A Mechanistic study of Plasma Treatment Effects on Demineralized Dentin Surfaces for Improved Adhesive/Dentin Interface Bonding

    Dong, Xiaoqing; Chen, Meng; Wang, Yong; Yu, Qingsong

    2014-01-01

    Our previous work has shown that non-thermal plasma treatment of demineralized dentin significantly (p<0.05) improved adhesive/dentin bonding strength for dental composite restoration as compared with the untreated controls. This study is to achieve mechanistic understanding of the plasma treatment effects on dentin surface through investigating the plasma treated dentin surfaces and their interaction with adhesive monomer, 2-Hydroxyethyl methacrylate (HEMA). The plasma treated dentin surfaces from human third molars were evaluated by water contact angle measurements and scanning electron microscopy (SEM). It was found that plasma-treated dentin surface with subsequent HEMA immersion (Plasma/HEMA Treated) had much lower water contact angle compared with only plasma-treated (Plasma Treated) or only HEMA immersed (HEMA Treated) dentin surfaces. With prolong water droplet deposition time, water droplets spread out completely on the Plasma/HEMA Treated dentin surfaces. SEM images of Plasma/HEMA Treated dentin surfaces verified that dentin tubules were opened-up and filled with HEMA monomers. Extracted type I collagen fibrils, which was used as simulation of the exposed dentinal collagen fibrils after acid etching step, were plasma treated and analyzed with Fourier transform infrared spectroscopy (FT-IR) and circular dichroism (CD) spectra. FT-IR spectra of the Plasma/HEMA Treated collage fibrils showed broadened amide I peak at 1660 cm−1 and amide II at 1550 cm−1, which indicate secondary structure changes of the collagen fibrils. CD spectra indicated that 67.4% collagen helix structures were denatured after plasma treatment. These experimental results demonstrate that non-thermal argon plasma treatment was very effective in loosing collagen structure and enhancing adhesive monomer penetration, which are beneficial to thicker hybrid layer and longer resin tag formation, and consequently enhance adhesive/dentin interface bonding. PMID:25267936

  11. Effect of polymerization mode of two adhesive systems on push-out bond strength of fiber post to different regions of root canal dentin

    Shahram Farzin Ebrahimi

    2014-01-01

    Full Text Available Background: A few studies have investigated the effect of the activation mode of adhesive systems on bond strength of fiber posts to root canal dentin. This study investigated the push-out bond strengths of a glass fiber post to different root canal regions with the use of two adhesives with light- and dual-cure polymerization modes. Materials and Methods: In this in vitro study, 40 maxillary central incisors were decoronated at cement-enamel junction with 15 ± 1 mm root length. After root canal therapy and post space preparations, they were randomly divided into four groups. Post spaces were treated with four different adhesives: Excite, Excite Dual cure Single Component (DSC, self-etch adhesive (AdheSE, and AdheSE dual-cure. Then the fiber-reinforced composite (FRC post, Postec Plus, was cemented with dual-cure resin cement, Variolink II. The roots were cut into three 2-mm-thick slices. Push-out tests were performed with a universal testing machine at a crosshead speed of 0.5 mm/min. The mode of failures was determined under a stereomicroscope. Data were analyzed by three-way analysis of variance (ANOVA and Tukey test was conducted to compare post hoc with P < 0.05 as the level of significance. Results: The highest bond strength was obtained for AdheSE dual-cure (15.54 ± 6.90 MPa and the lowest was obtained for Excite light-cure (10.07 ± 7.45 MPa and only the bond strength between these two adhesives had significant difference (P = 0.02. Bond strength decreased from the coronal to the apical in all groups and this was significant in Excite (group 1 and AdheSE (group 3 (P < 0.001. In apical regions, bond strength of dual-cure adhesives was significantly higher than light-cure adhesives (P < 0.001. Conclusion: Push-out bond strength of fiber post to different regions of root canal dentin was affected by both adhesive systems and their polymerization modes.

  12. Biomechanics of P-selectin PSGL-1 bonds: Shear threshold and integrin-independent cell adhesion

    Xiao, Zhihua; Goldsmith, Harry L.; MacIntosh, Fiona A.; Shankaran, Harish; Neelamegham, Sriram

    2006-03-01

    Platelet-leukocyte adhesion may contribute to thrombosis and inflammation. We examined the heterotypic interaction between unactivated neutrophils and either thrombin receptor activating peptide (TRAP) stimulated platelets or P-selectin bearing beads (Ps-beads) in suspension. Cone-plate viscometers were used to apply controlled shear rates from 14-3000/s. Platelet-neutrophil and bead-neutrophil adhesion analysis was performed using both flow cytometry and high-speed videomicroscopy. We observed that while blocking antibodies against either P-selectin or P-selectin glycoprotein ligand-1 (PSGL-1) alone inhibited platelet-neutrophil adhesion by ~60% at 140/s, these reagents completely blocked adhesion at 3000/s. Anti-Mac-1 alone did not alter platelet-neutrophil adhesion rates at any shear rate, though in synergy with selectin antagonists it abrogated cell binding. Unstimulated neutrophils avidly bound Ps-beads and activated platelets in an integrin-independent manner, suggesting that purely selectin-dependent cell adhesion is possible. In support of this, antagonists against P-selectin or PSGL-1 dissociated previously formed platelet-neutrophil and Ps-bead neutrophil aggregates under shear in a variety of experimental systems, including in assays performed with whole blood. In studies where medium viscosity and shear rate were varied, a subtle shear threshold for P-selectin PSGL-1 binding was also noted at shear rates<100/s and at force loading rates of ~300pN/sec. Results are discussed in light of biophysical computations that characterize the collision between unequal size particles in linear shear flow. Overall, our studies reveal an integrin-independent regime for cell adhesion that may be physiologically relevant.

  13. Effect of collagen cross-linkers on the shear bond strength of a self-etch adhesive system to deep dentin

    Sakhamuri Srinivasulu; Sampath Vidhya; Manimaran Sujatha; Sekar Mahalaxmi

    2013-01-01

    Objectives: To evaluate the shear bond strength of composite resin to deep dentin, bonded using a self-etch adhesive, after treatment with two collagen cross-linkers at varying time intervals. Materials and Methods: Thirty extracted human incisors were sectioned longitudinally into equal mesial and distal halves ( n = 60). The proximal deep dentin was exposed and the specimens were divided based on the surface treatment of dentin prior to bonding as follows: Group I ( n = 12, control): No...

  14. Experimental Investigations on the Influence of Adhesive Oxides on the Metal-Ceramic Bond

    Enghardt, Susanne; Richter, Gert; Richter, Edgar; Reitemeier, Bernd; Walter, Michael

    2015-01-01

    ISO 25178), scanning electron microscopy (SEM) imaging, auger electron spectroscopy (AES) and energy dispersive X-ray analysis (EDX). Ion implantation resulted in no increase in bond strength. The highest shear bond strengths were achieved after oxidation in air and air abrasion with Al2O3 (41.5 MPa and 47.8 MPa respectively). There was a positive correlation between shear bond strength and profile height. After air abrasion, a pronounced structuring of the surface occurred compared to ion im...

  15. Experimental Investigations on the Influence of Adhesive Oxides on the Metal-Ceramic Bond

    Susanne Enghardt

    2015-01-01

    Full Text Available The objective of this study was to test the influence of selected base metals, which act as oxide formers, on the metal-ceramic bond of dental veneer systems. Using ion implantation techniques, ions of Al, In and Cu were introduced into near-surface layers of a noble metal alloy containing no base metals. A noble metal alloy with base metals added for oxide formation was used as a reference. Both alloys were coated with a low-temperature fusing dental ceramic. Specimens without ion implantation or with Al2O3 air abrasion were used as controls. The test procedures comprised the Schwickerath shear bond strength test (ISO 9693-1, profile height (surface roughness measurements (ISO 4287; ISO 4288; ISO 25178, scanning electron microscopy (SEM imaging, auger electron spectroscopy (AES and energy dispersive X-ray analysis (EDX. Ion implantation resulted in no increase in bond strength. The highest shear bond strengths were achieved after oxidation in air and air abrasion with Al2O3 (41.5 MPa and 47.8 MPa respectively. There was a positive correlation between shear bond strength and profile height. After air abrasion, a pronounced structuring of the surface occurred compared to ion implantation. The established concentration shifts in alloy and ceramic could be reproduced. However, their positive effects on shear bond strength were not confirmed. The mechanical bond appears to be of greater importance for metal-ceramic bonding.

  16. Development of a shock wave adhesion test for composite bonds by laser pulsed and mechanical impacts

    Ecault, Romain; Boustie, Michel; Touchard, Fabienne; Arrigoni, Michel; Berthe, Laurent; CNRS Collaboration

    2013-06-01

    Evaluating the bonding quality of composite material is becoming one of the main challenges faced by aeronautic industries. This work aims the development of a technique using shock wave, which would enable to quantify the bonding mechanical quality. Laser shock experiments were carried out. This technique enables high tensile stress generation in the thickness of composite bond without any mechanical contact. The resulting damage has been quantified using different method such as confocal microscopy, ultrasound and cross section observation. The discrimination between a correct bond and a weak bond was possible thanks to these experiments. Nevertheless, laser sources are not well adapted for optimization of such a test since it has often fixed parameters. That is why mechanical impacts bonded composites were also performed in this work. By changing the thickness of aluminum projectiles, the tensile stresses generated by the shock wave propagation were moved toward the composite/bond interface. The observations made prove that the optimization of the technique is possible. The key parameters for the development of a bonding test using shock wave have been identified.

  17. Development of a shock wave adhesion test for composite bonds by pulsed laser and mechanical impacts

    Ecault, R.; Boustie, M.; Touchard, F.; Arrigoni, M.; Berthe, L.

    2014-05-01

    Evaluating the bonding quality of composite material is becoming one of the main challenges faced by aeronautic industries. This work aims to the development of a technique using shock wave, which would enable to quantify the bonding mechanical quality. Laser shock experiments were carried out. This technique enables high tensile stress generation in the thickness of composite bonds. The resulting damage has been quantified using different methods such as confocal microscopy, ultrasound and cross section observation. The discrimination between a correct bond and a weak bond was possible thanks to these experiments. Nevertheless, laser sources are not well adapted for optimization of such a test because of often fixed settings. That is why mechanical impacts on bonded composites were also performed in this work. By changing the thickness of aluminum projectiles, the generated tensile stresses by the shock wave propagation were moved toward the composite/bond interface. The made observations prove that the technique optimization is possible. The key parameters for the development of a bonding test using shock waves have been identified.

  18. XPS and AES investigations of the adhesive bonding properties of thin titanium coatings

    The bonding properties of PMMA-microstructures on Ti-coated Cu-substrates after an oxidative treatment in alkaline hydrogenperoxide solution were investigated. In order to clarify the basic mechanism, surface analytical investigations by XPS-, AES-, and depth profile measurements have been performed. It was demonstrated that for optimum bonding a TiO2 surface layer of ca. 30 nm thickness is necessary. Chemical effects as well as a mechanical bonding with open grain boundary structures (dimensions in the μm-range) could be ruled out as bonding mechanisms. A mechanical interlocking of the polymer with micropores (dimensions in the nm-range) of the oxidic overlayer is adopted as the most probable bonding mechanism. (orig.)

  19. Effects of two soft drinks on shear bond strength and adhesive remnant index of orthodontic metal brackets.

    Soodabeh Sadat Sajadi

    2014-08-01

    Full Text Available Bond failure of brackets during orthodontic treatment is a common problem; which results in treatment interference, increased treatment time and prolonged clinical time for rebonding of failed brackets. The purpose of this study was to evaluate the effects of Coca-Cola and a non-alcoholic beer on the shear bond strength and adhesive remnant index (ARI of orthodontic metal brackets in vitro.Eighty intact human premolars were divided into two experimental groups of Coca-Cola and non-alcoholic beer (Istak, and a control group of artificial saliva. Over a period of thirty days, the test groups were immersed in the respective soft drinks for 5 minutes, twice a day. For the remainder of the time, they were kept in artificial saliva at 37°C. The control group was stored in artificial saliva during the experiment. All samples were subjected to shearing forces using Universal Testing Machine. ARI was determined with a stereomicroscope at ×12 magnification. The data of shear bond strength were statistically analyzed by one-way ANOVA and Tukey's Post-Hoc test and the data of ARI scores were analyzed by Kruskal-Wallis test.No significant difference was observed in ARIs of the three groups (P≤ 0.552. The shear bond strength of Coke group was significantly lower than that of the two other groups (P≤ 0.035; but there was no significant difference between the shear bond strength of Istak and the control group (P≤ 0.999.Coca-Cola decreased the shear bond strength of orthodontic brackets.

  20. Effects of Two Soft Drinks on Shear Bond Strength and Adhesive Remnant Index of Orthodontic Metal Brackets

    Sajadi, Soodabeh Sadat; Eslami Amirabadi, Gholamreza; Sajadi, Sepideh

    2014-01-01

    Objective: Bond failure of brackets during orthodontic treatment is a common problem; which results in treatment interference, increased treatment time and prolonged clinical time for rebonding of failed brackets. The purpose of this study was to evaluate the effects of Coca-Cola and a non-alcoholic beer on the shear bond strength and adhesive remnant index (ARI) of orthodontic metal brackets in vitro. Materials and Methods: Eighty intact human premolars were divided into two experimental groups of Coca-Cola and non-alcoholic beer (Istak), and a control group of artificial saliva. Over a period of thirty days, the test groups were immersed in the respective soft drinks for 5 minutes, twice a day. For the remainder of the time, they were kept in artificial saliva at 37°C. The control group was stored in artificial saliva during the experiment. All samples were subjected to shearing forces using Universal Testing Machine. ARI was determined with a stereomicroscope at ×12 magnification. The data of shear bond strength were statistically analyzed by one-way ANOVA and Tukey’s Post-Hoc test and the data of ARI scores were analyzed by Kruskal-Wallis test. Results: No significant difference was observed in ARIs of the three groups (P≤ 0.552). The shear bond strength of Coke group was significantly lower than that of the two other groups (P≤ 0.035); but there was no significant difference between the shear bond strength of Istak and the control group (P≤ 0.999). Conclusion: Coca-Cola decreased the shear bond strength of orthodontic brackets. PMID:25584049

  1. Effects of Platinum Additions and Sulfur Impurities on the Microstructure and Scale Adhesion Behavior of Single-Phase CVD Aluminide Bond Coatings

    Cooley, K.M.; Haynes, J.A.; Lee, W.Y.; Pint, B.A.; Wright, I.G.; Zhang, Y.

    1999-02-28

    The adhesion of alumina scales to aluminide bond coats is a life-limiting factor for some advanced thermal barrier coating systems. This study investigated the effects of aluminide bond coat sulfur and platinum contents on alumina scale adhesion and coating microstructural evolution during isothermal and cyclic oxidation testing at 1150 C. Low-sulfur NiAl and NiPtAl bond coats were fabricated by chemical vapor deposition (CVD). Lowering the sulfur contents of CVD NiAl bond coatings significantly improved scale adhesion, but localized scale spallation eventually initiated along coating grain boundaries. Further improvements in scale adhesion were obtained with Pt additions. The observed influences of Pt additions included: (1) mitigation of the detrimental effects of high sulfur levels, (2) drastic reductions in void growth along the scale-metal interface, (3) alteration of the oxide-metal interface morphology, and (4) elimination of Ta-rich oxides in the Al{sub 2}O{sub 3} scales during thermal cycling. The results of this study also suggested that the microstructure (especially the grain size) of CVD aluminide bond coatings plays a significant role in scale adhesion.

  2. Development of the anode bipolar plate/membrane assembly unit for air breathing PEMFC stack using silicone adhesive bonding

    Kim, Minkook; Lee, Dai Gil

    2016-05-01

    Polymer electrolyte membrane fuel cells (PEMFC) exhibit a wide power range, low operating temperature, high energy density and long life time. These advantages favor PEMFC for applications such as vehicle power sources, portable power, and backup power applications. With the push towards the commercialization of PEMFC, especially for portable power applications, the overall balance of plants (BOPs) of the systems should be minimized. To reduce the mass and complexity of the systems, air-breathing PEMFC stack design with open cathode channel configuration is being developed. However, the open cathode channel configuration incurs hydrogen leakage problem. In this study, the bonding strength of a silicon adhesive between the Nafion membrane and the carbon fiber/epoxy composite bipolar plate was measured. Then, an anode bipolar plate/membrane assembly unit which was bonded with the silicone adhesive was developed to solve the hydrogen leakage problem. The reliability of the anode bipolar plate/membrane assembly unit was estimated under the internal pressure of hydrogen by the FE analysis. Additionally, the gas sealability of the developed air breathing PEMFC unit cell was experimentally measured. Finally, unit cell performance of the developed anode bipolar plate/membrane assembly unit was tested and verified under operating conditions without humidity and temperature control.

  3. Effect of adhesive resin type for bonding to zirconia using two surface pretreatments

    P. Samimi; A. Hasankhani; J.P. Matinlinna; H. Mirmohammadi

    2015-01-01

    Purpose: This laboratory study evaluated the short-term adhesive properties of one 10-MDP-containing and two MDP-free resin composite cements, using two types of zirconia surface pretreatments. Materials and Methods: Eighteen sintered zirconia disks (Procera, Nobel Biocare) were randomly divided int

  4. Acid Neutralizing Ability and Shear Bond Strength Using Orthodontic Adhesives Containing Three Different Types of Bioactive Glass

    Song-Yi Yang

    2016-02-01

    Full Text Available The objective of the study was to compare the acid neutralizing ability and shear bond strength (SBS of three different types of orthodontic adhesives containing bioactive glasses (BAGs. 45S5, 45S5F and S53P4 BAGs were prepared using the melting technique and ground to fine particles. Orthodontic adhesives containing three types of BAGs were prepared as follows: 52.5% 45S5 BAG + 17.5% glass (45S5_A; 61.25% 45S5 BAG + 8.75% glass (45S5_B; 52.5% 45S5F BAG + 17.5% glass (45S5F_A; 61.25% 45S5F BAG + 8.75% glass (45S5F_B; 52.5% S53P4 BAG + 17.5% glass (S53P4_A; 61.25% S53P4 BAG + 8.75% glass (S53P4_B; and 70.0% glass (BAG_0. To evaluate the acid neutralizing properties, specimens were immersed in lactic acid solution, and pH changes were measured. SBS was measured with a universal testing machine. For all of the BAG-containing adhesives, the one with 61.25% of BAG showed a significantly greater increase of pH than the one with 52.5% of BAG (p < 0.05. Groups with 61.25% of BAG showed lower SBS than samples with 52.5% of BAG. 45S5F_A showed no significant difference of SBS compared to BAG_0 (p > 0.05. The adhesive containing 61.25% of 45S5F BAG exhibited clinically acceptable SBS and acid neutralizing properties. Therefore, this composition is a suitable candidate to prevent white spot lesions during orthodontic treatment.

  5. Theoretical modeling of the catch-slip bond transition in biological adhesion

    Gunnerson, Kim; Pereverzev, Yuriy; Prezhdo, Oleg

    2006-05-01

    The mechanism by which leukocytes leave the blood stream and enter inflamed tissue is called extravasation. This process is facilitated by the ability of selectin proteins, produced by the endothelial cells of blood vessels, to form transient bonds with the leukocytes. In the case of P-selectin, the protein bonds with P-selectin glycoprotein ligands (PSGL-1) produced by the leukocyte. Recent atomic force microscopy and flow chamber analyses of the binding of P-selectin to PSGL-1 provide evidence for an unusual biphasic catch-bond/slip-bond behavior in response to the strength of exerted force. This biphasic process is not well-understood. There are several theoretical models for describing this phenomenon. These models use different profiles for potential energy landscapes and how they change under forces. We are exploring these changes using molecular dynamics. We will present a simple theoretical model as well as share some of our early MD results for describing this phenomenon.

  6. Evaluation of microshear bond strength of resin composites to enamel of dental adhesive systems associated with Er,Cr:YSGG laser

    Cassimiro-Silva, Patricia F.; Zezell, Denise M.; Monteiro, Gabriela Q. d. M.; Benetti, Carolina; de Paula Eduardo, Carlos; Gomes, Anderson S. L.

    2016-02-01

    The aim of this in vitro study was to evaluate the microshear bond strength (μSBS) of resin composite to enamel etching by Er,Cr:YSGG laser with the use of two differents adhesives systems. Fifty freshly extracted human molars halves were embedded in acrylic resin before preparation for the study, making a total of up to 100 available samples. The specimens were randomly assigned into six groups (η=10) according to substrate pre-treatment and adhesive system on the enamel. A two-step self-etching primer system (Clearfil SE Bond) and a universal adhesive used as an etch-andrinse adhesive (Adper Single Bond Universal) were applied to the nonirradiated enamel surface according to manufacturer's instructions, as control groups (Control CF and Control SB, respectively). For the other groups, enamel surfaces were previously irradiated with the Er,Cr:YSGG laser with 0.5 W, 75 mJ and 66 J/cm2 (CF 5 Hz and SB 5 Hz) and 1.25 W, 50 mJ and 44 J/cm2 (CF 15 Hz and SB 15 Hz). Irradiation was performed under air (50%) and water (50%) cooling. An independent t-test was performed to compare the adhesive systems. Mean μSBS ± sd (MPa) for each group was 16.857 +/- 2.61, 17.87 +/- 5.83, 12.23 +/- 2.02, 9.88 +/- 2.26, 15.94 +/- 1.98, 17.62 +/- 2.10, respectively. The control groups and the 50 mJ laser groups showed no statistically significant differences, regardless of the adhesive system used. The results obtained lead us to affirm that the bonding interaction of adhesives to enamel depends not only on the morphological aspects of the dental surface, but also on the characteristics of the adhesive employed and the parameters of the laser.

  7. Durable bonds at the adhesive/dentin interface: an impossible mission or simply a moving target?

    Spencer, Paulette; Jonggu PARK, Qiang YE; Misra, Anil; Bohaty, Brenda S; Singh, Viraj; PARTHASARATHY, Ranga; SENE, Fábio; de Paiva GONÇALVES, Sérgio Eduardo; LAURENCE, Jennifer

    2012-01-01

    Composite restorations have higher failure rates, more recurrent caries and increased frequency of replacement as compared to dental amalgam. Penetration of bacterial enzymes, oral fluids, and bacteria into the crevices between the tooth and composite undermines the restoration and leads to recurrent decay and failure. The gingival margin of composite restora tions is particularly vulnerable to decay and at this margin, the adhesive and its seal to dentin provides the primary barrier between ...

  8. All-glass shell scale models made with an adjustable mould

    Belis, JLIF Jan; Pronk, ADC Arno; Schuurmans, WB; Blancke, T

    2011-01-01

    Ever since Lucio Blandini developed a doubly curved synclastic shell with adhesively bonded glass components, the concept of building a self-supporting glass-only shell has almost become within reach. In the current contribution a small-scaled experimental concept is presented of a self-supporting anticlastic all-glass shell scale model, created by means of an adaptable mould. First, different manufacturing parameters of relatively small shells are investigated, such as mould type, glass s...

  9. The Effect of Composite Patches on the Failure of Adhesively-Bonded Joints Under Bending Moment

    Akpinar, Salih

    2013-12-01

    In this study, it was aimed to compare mechanical behavior of double-strap joints with aluminum (AA2024-T3) or 16-ply laminate of carbon/epoxy composite (T300/934) patches of different orientation angles at their overlap area subjected to bending moment. For this purpose, AA2024-T3 aluminum was used as adherend, while the adhesive was a two-part paste (DP 460). Six different types of joint samples were subjected to bending moment. The effect of patch material on failure load and stress distribution was examined experimentally and numerically. In the numerical analysis, the composite patches were assumed to behave linearly elastic, while adherend and adhesive layers were assumed to be nonlinear. It was found that the data obtained from 3-D finite element analysis were coherent with experimental results. Meanwhile, experiments showed that fiber orientation angles of the patches markedly affected the failure load of joints, failure mode and stress distributions appeared in adhesive and composite.

  10. Transfer of thin Au films to polydimethylsiloxane (PDMS) with reliable bonding using (3-mercaptopropyl)trimethoxysilane (MPTMS) as a molecular adhesive

    This paper describes the transfer of thin gold films deposited on rigid silicon substrates to polydimethylsiloxane (PDMS) with reliable and strong bonding. Modification of the Au surfaces with (3-mercaptopropyl)trimethoxysilane (MPTMS) as a molecular adhesive was carried out to promote adhesion between Au and PDMS. The degree of bonding with respect to the concentration of MPTMS, treatment time and methods of deposition was investigated by a simple adhesion test using two different adhesive tapes. The effect of hydrolysis of MPTMS is discussed based on the bonding mechanism of MPTMS to the PDMS prepolymer. Also, the adsorption of MPTMS on Au deposited by different methods is discussed. The results indicate that liquid deposition of MPTMS provides the strongest adhesion between Au and PDMS among the different deposition methods and the different linker molecules. Based on these studies, the Au patterns with linewidth of less 2 µm were successfully transferred to PDMS with reliable and strong bonding in a full 3 inch wafer scale, using a dry peel-off process. (paper)

  11. Effect of biological contamination on dentine bond strength of adhesive resins.

    van Schalkwyk, J H; Botha, F S; van der Vyver, P J; de Wet, F A; Botha, S J

    2003-05-01

    The purpose of this in vitro study was to determine the effect of saliva (S) and blood (B) contamination on the dentine bond strength of two single-component dentine bonding systems. The occlusal thirds of 120 recently extracted, human molars were removed with a low speed saw and subsequently embedded in Bencor rings by means of self-curing, acrylic resin. The occlusal surfaces were ground wet on 600-grit silicone carbide paper in a polishing machine to expose superficial dentine and to create a smear layer. The teeth were randomly divided into 12 groups (n = 10). All the dentine surfaces were etched with 34% phosphoric acid for 15 seconds rinsed with water, air-dried for 3 seconds, leaving the surfaces visibly moist. For the control groups (C) the etched dentine surfaces were treated with either, Scotchbond 1 (SB1, 3M) or Prime & Bond NT (PBNT, Dentsply) according to the manufacturer's instructions. In the contaminated groups, the saliva or blood was applied by means of a disposable brush, left undisturbed for 1 minute, and the excess then thinned by air spray. The dentine bonding systems were then applied, also according to manufacturer's instructions. Composite (Z250 and TPH) and Compomer (F2000 and Dyract AP (D-AP)) stubs were packed and cured incrementally to the corresponding pretreated dentine surfaces. All specimens were stored for 24 hours under water at 37 degrees C. The bonds were then stressed to failure with a Zwick testing machine, operating at a crosshead speed of 0.5 mm/min. Fractured samples were examined in a Scanning Electron Microscope. The data were statistically analysed (Student-t test). The mean SBS (MPa) were. SB1 with Z250: C = 19.1 +/- 4.4; S = 17.3 +/- 3.5; B = 2.6 +/- 0.9; SB1 with F2000: C = 11.8 +/- 3.3; S = 9.7 +/- 1.8; B = 4.7 +/- 1.6. PBNT with TPH: C = 9.2 +/- 3.2; S = 6.5 +/- 3.0; B = 4.3 +/- 1.5; PBNT with D-AP: C = 10.2 +/- 3.6; S = 9.3 +/- 2.9 and B = 7.3 +/- 2.5. There was no statistical significant difference in shear bond

  12. In vitro comparative bond strength of contemporary self-adhesive resin cements to zirconium oxide ceramic with and without air-particle abrasion.

    Blatz, Markus B; Phark, Jin-Ho; Ozer, Fusun; Mante, Francis K; Saleh, Najeed; Bergler, Michael; Sadan, Avishai

    2010-04-01

    This study compared shear bond strengths of six self-adhesive resin cements to zirconium oxide ceramic with and without air-particle abrasion. One hundred twenty zirconia samples were air-abraded (group SB; n = 60) or left untreated (group NO). Composite cylinders were bonded to the zirconia samples with either BisCem (BC), Maxcem (MC), G-Cem (GC), RelyX Unicem Clicker (RUC), RelyX Unicem Applicator (RUA), or Clearfil SA Cement (CSA). Shear bond strength was tested after thermocycling, and data were analyzed with analysis of variance and Holm-Sidak pairwise comparisons. Without abrasion, RUA (8.0 MPa), GC (7.9 MPa), and CSA (7.6 MPa) revealed significantly higher bond strengths than the other cements. Air-particle abrasion increased bond strengths for all test cements (p CSA (18.4 MPa) revealed the highest bond strengths in group SB. Bond strengths of self-adhesive resin cements to zirconia were increased by air-particle abrasion. Cements containing adhesive monomers (MDP/4-META) were superior to other compositions. PMID:19415350

  13. Adhesion and Cohesion

    J. Anthony von Fraunhofer

    2012-01-01

    Full Text Available The phenomena of adhesion and cohesion are reviewed and discussed with particular reference to dentistry. This review considers the forces involved in cohesion and adhesion together with the mechanisms of adhesion and the underlying molecular processes involved in bonding of dissimilar materials. The forces involved in surface tension, surface wetting, chemical adhesion, dispersive adhesion, diffusive adhesion, and mechanical adhesion are reviewed in detail and examples relevant to adhesive dentistry and bonding are given. Substrate surface chemistry and its influence on adhesion, together with the properties of adhesive materials, are evaluated. The underlying mechanisms involved in adhesion failure are covered. The relevance of the adhesion zone and its importance with regard to adhesive dentistry and bonding to enamel and dentin is discussed.

  14. Wall-lesion development in gaps: The role of the adhesive bonding material

    Montagner, A.F.; Kuper, N.K.; Opdam, N.J.M.; Bronkhorst, E.M.; Cenci, M.S.; Huysmans, M.C.D.N.J.M.

    2015-01-01

    OBJECTIVES: This study evaluated the caries wall lesion development in different composite-dentin interfaces to investigate if the presence and location of two bonding materials in the gaps influence wall caries lesion development. METHODS: Fourteen volunteers wore a modified occlusal splint contain

  15. Shear bond strength evaluation of resin composite bonded to three different liners: TheraCal LC, Biodentine, and resin-modified glass ionomer cement using universal adhesive: An in vitro study

    Deepa, Velagala L; Dhamaraju, Bhargavi; Bollu, Indira Priyadharsini; Balaji, Tandri S

    2016-01-01

    Aims: To compare and evaluate the bonding ability of resin composite (RC) to three different liners: TheraCal LC™ (TLC), a novel resin-modified (RM) calcium silicate cement, Biodentine™ (BD), and resin-modified glass ionomer cement (RMGIC) using an universal silane-containing adhesive and characterizing their failure modes. Materials and Methods: Thirty extracted intact human molars with occlusal cavity (6-mm diameter and 2-mm height) were mounted in acrylic blocks and divided into three groups of 10 samples each based on the liner used as Group A (TLC), Group B (BD), and Group C (RMGIC). Composite post of 3 mm diameter and 3 mm height was then bonded to each sample using universal adhesive. Shear bond strength (SBS) analysis was performed at a cross-head speed of 1 mm/min. Statistical Analysis Used: Statistical analysis was performed with one-way analysis of variance (ANOVA) and post hoc test using Statistical Package for the Social Sciences (SPSS) version 20. Results: No significant difference was observed between group A and group C (P = 0.573) while group B showed the least bond strength values with a highly significant difference (P = 0.000). The modes of failure were predominantly cohesive in Groups A and B (TLC and BD) while RMGIC showed mixed and adhesive failures. Conclusions: Hence, this present study concludes that the bond strength of composite resin to TLC and RMGIC was similar and significantly higher than that of BD following application of universal adhesive. PMID:27099425

  16. Processing conditions analysis of Eucalyptus globulus plywood bonded with resol-tannin adhesives.

    Stefani, P M; Peña, C; Ruseckaite, R A; Piter, J C; Mondragon, I

    2008-09-01

    Phenol-formaldehyde resol containing mimosa tannin extract was employed to produce plywood panels with two plies from Eucalyptus globulus veneers. The effect of processing conditions and tannin content on the gelation time of the adhesive in the glue line was evaluated by dynamic-mechanical analysis (DMA). These results were related with shear strength and wood failure of glue line in the final panels. Hazardous petrochemical phenol could be partially substituted in resols in industrial applications by addition of mimosa tannin extracts. PMID:18024109

  17. In vitro evaluation of casein phosphopeptide-amorphous calcium phosphate effect on the shear bond strength of dental adhesives to enamel

    Shadman, Niloofar; Ebrahimi, Shahram Farzin; Shoul, Maryam Azizi; Sattari, Hasti

    2015-01-01

    Background: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is applied for remineralization of early caries lesions or tooth sensitivity conditions and may affect subsequent resin bonding. This in vitro study investigated the effect of CPP-ACP on the shear bond strength of dental adhesives to enamel. Materials and Methods: Sixty extracted human molar teeth were selected and randomly divided into three groups and six subgroups. Buccal or lingual surfaces of teeth were prepared to c...

  18. In vitro evaluation of casein phosphopeptide-amorphous calcium phosphate effect on the shear bond strength of dental adhesives to enamel

    Niloofar Shadman; Shahram Farzin Ebrahimi; Maryam Azizi Shoul; Hasti Sattari

    2015-01-01

    Background: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is applied for remineralization of early caries lesions or tooth sensitivity conditions and may affect subsequent resin bonding. This in vitro study investigated the effect of CPP-ACP on the shear bond strength of dental adhesives to enamel. Materials and Methods: Sixty extracted human molar teeth were selected and randomly divided into three groups and six subgroups. Buccal or lingual surfaces of teeth were prepared ...

  19. Treatment of CFRP by IAR method and its effect on the fracture behavior of adhesive bonded CFRP/aluminum composites

    It was shown in the previous studies that adhesive shear strength of carbon fiber reinforced plastics (CFRP) to aluminum composites could be improved by the surface treatment of CFRP using Ar+ ion irradiation. In the present work, the effect of CFRP treatment by Ar+ ion irradiation on the fracture behavior of CFRP/aluminum joint was studied. The aluminum used was 7075-T6 and the CFRP used was multi-directional graphite/epoxy composites whose stacking sequence was [0 deg. /±45 deg. /0 deg. ]3s. The surface of CFRP was treated using Ar+ ion irradiation in an oxygen environment. The Ar+ ion dose used was 1x1016 ions cm-2. Fracture toughness of CFRP/aluminum joint was determined from cracked lap shear specimens using work factor approach. Then, the fracture toughness of ion beam-treated CFRP/aluminum joint was compared with that of untreated CFRP/aluminum joint. The results showed that the fracture toughness of ion beam-treated CFRP/aluminum case was about 72% higher than that of untreated CFRP/aluminum case. X-ray photoelectron spectrometer analysis showed that intensity of hydrophilic bonds, C-O (carbonyl group) and O-C-O (carboxyl group) was increased by the Ar+ ion-irradiation in an oxygen environment. Scanning electron microscope examination showed that cohesive failure occurred for ion beam-treated CFRP/aluminum joint while adhesive failure occurred for untreated CFRP/aluminum joint

  20. Evaluation of Surlyn 8920 as PHE Visor Material and Evaluations of New Adhesives for Improving Bonding Between Teflon and Stainless Steel at Cryogenic Temperature

    Ray, Asit K.

    1991-01-01

    Two studies are presented, and in the first study, Surlyn 8920 (an ionic and amorphous low density polyethylene made by Dupont) was evaluated as a possible replacement of Plexyglass G as PHE visor material. Four formulations of the polymer were made by adding different amounts of UV stabilizer, energy quencher, and antioxident in a Brabender Plasticorder. The formulated polymers were molded in the form of sheets in a compression molder. Cut samples from the molded sheets were exposed in a weatherometer and tested on Instron Tensile Tester for strength and elongation. Specially molded samples of the formulated polymers were subjected to Charpy Impact Tests. In the second study, preliminary evaluations of adhesives for improvement of bonding between Teflon and stainless steel (SS) were performed. Kapton, a high temperature polyimide made by Dupont, and a rubber based adhesive made by Potter Paint Co., were evaluated against industrial quality epoxy, the current material used to bond Teflon and SS. The degreased surfaces of the SS discs were etched mechanically, with a few of these etched chemically. The surfaces of the SS discs were etched mechanically, with a few of these etched chemically. Bonding strengths were evaluated using lap shear tests on the Instron Tensile Tester for the samples bonded by Kapton and industrial quality epoxy. Bond strengths were also evaluated using a pull test on the Instron for the samples bonded by Potter adhesive (CWL-152) and industrial quality epoxy. Based on limited lap shear data, Kapton gave bond strength favorable compared to that of industrial epoxy. Based on limited pull test data, Kapton bonded and CWL-152 bonded samples showed poor strength compared to epoxy bonded sample.

  1. Direct integration of MEMS, dielectric pumping and cell manipulation with reversibly bonded gecko adhesive microfluidics

    Warnat, S.; King, H.; Wasay, A.; Sameoto, D.; Hubbard, T.

    2016-09-01

    We present an approach to form a microfluidic environment on top of MEMS dies using reversibly bonded microfluidics. The reversible polymeric microfluidics moulds bond to the MEMS die using a gecko-inspired gasket architecture. In this study the formed microchannels are demonstrated in conjunction with a MEMS mechanical single cell testing environment for BioMEMS applications. A reversible microfluidics placement technique with an x-y and rotational accuracy of  ±2 µm and 1° respectively on a MEMS die was developed. No leaks were observed during pneumatic pumping of common cell media (PBS, sorbitol, water, seawater) through the fluidic channels. Thermal chevron actuators were successful operated inside this fluidic environment and a performance deviation of ~15% was measured compared to an open MEMS configuration. Latex micro-spheres were pumped using traveling wave di-electrophoresis and compared to an open (no-microfluidics) configuration with velocities of 24 µm s‑1 and 20 µm s‑1.

  2. Aging Effects of Environmentally-Friendly Cleaners on Adhesive Bond Integrity

    Biegert, L. L.; Anderson, G. L.; Evans, K. B.; Olsen, B. D.; Weber, B. L.; McCool, A. A. (Technical Monitor)

    2000-01-01

    Because of the 1990 Clean Air Act Amendment many chlorinated solvents are being phased out of use in manufacturing industries. Replacement of the ODC (ozone- depleting chemicals) with less volatile, non-ozone depleting cleaners has been extensively studied over the past nine years at Thiokol Propulsion, Cordant Technologies. Many of the non-ODC cleaners contain compounds that can potentially degrade over time under conditions of high temperature, humidity and exposure to light. The chemical composition of environmentally conditioned cleaners and the subsequent effect on aluminum/amine-cured epoxy bond integrity as measured by Tapered Double Cantilever Beam were evaluated. From this study it is observed that moisture content increases for those cleaners containing polar compounds. Non-volatile residue content increases as stabilizers are depleted and the chemical compound limonene is oxidized. A change in aluminum/ amine-cured epoxy bond fracture toughness is observed as some of these cleaners age with increases in moisture and NVR content.

  3. The Role of Host-derived Dentinal Matrix Metalloproteinases in Reducing Dentin Bonding of Resin Adhesives

    Zhang, Shan-chuan; Kern, Matthias

    2009-01-01

    Dentin matrix metalloproteinases (MMPs) are a family of host-derived proteolytic enzymes trapped within mineralized dentin matrix, which have the ability to hydrolyze the organic matrix of demineralized dentin. After bonding with resins to dentin there are usually some exposed collagen fibrils at the bottom of the hybrid layer owing to imperfect resin impregnation of the demineralized dentin matrix. Exposed collagen fibrils might be affected by MMPs inducing hydrolytic degradation, which migh...

  4. Bond strength of composite to dentin: effect of acid etching and laser irradiation through an uncured self-etch adhesive system

    Castro, F. L. A.; Carvalho, J. G.; Andrade, M. F.; Saad, J. R. C.; Hebling, J.; Lizarelli, R. F. Z.

    2014-08-01

    This study evaluated the effect on micro-tensile bond strength (µ-TBS) of laser irradiation of etched/unetched dentin through an uncured self-etching adhesive. Dentinal surfaces were treated with Clearfil SE Bond Adhesive (CSE) either according to the manufacturer’s instructions (CSE) or without applying the primer (CSE/NP). The dentin was irradiated through the uncured adhesive, using an Nd:YAG laser at 0.75 or 1 W power settings. The adhesive was cured, composite crowns were built up, and the teeth were sectioned into beams (0.49 mm2) to be stressed under tension. Data were analyzed using one-way ANOVA and Tukey statistics (α = 5%). Dentin of the fractured specimens and the interfaces of untested beams were observed under scanning electron microscopy (SEM). The results showed that non-etched irradiated surfaces presented higher µ-TBS than etched and irradiated surfaces (p 0.05). SEM showed solidification globules on the surfaces of the specimens. The interfaces were similar on irradiated and non-irradiated surfaces. Laser irradiation of dentin through the uncured adhesive did not lead to higher µ-TBS when compared to the suggested manufacturer’s technique. However, this treatment brought benefits when performed on unetched dentin, since bond strengths were higher when compared to etched dentin.

  5. Interfacial fracture of dentin adhesively bonded to quartz-fiber reinforced composite

    The paper presents the results of an experimental study of interfacial failure in a multilayered structure consisting of a dentin/resin cement/quartz-fiber reinforced composite (FRC). Slices of dentin close to the pulp chamber were sandwiched by two half-circle discs made of a quartz-fiber reinforced composite, bonded with bonding agent (All-bond 2, BISCO, Schaumburg) and resin cement (Duo-link, BISCO, Schaumburg) to make Brazil-nut sandwich specimens for interfacial toughness testing. Interfacial fracture toughness (strain energy release rate, G) was measured as a function of mode mixity by changing loading angles from 0 deg. to 15 deg. The interfacial fracture surfaces were then examined using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) to determine the failure modes when loading angles changed. A computational model was also developed to calculate the driving forces, stress intensity factors and mode mixities. Interfacial toughness increased from ∼ 1.5 to 3.2 J/m2 when the loading angle increases from ∼ 0 to 15 deg. The hybridized dentin/cement interface appeared to be tougher than the resin cement/quartz-fiber reinforced epoxy. The Brazil-nut sandwich specimen was a suitable method to investigate the mechanical integrity of dentin/cement/FRC interfaces.

  6. Interfacial fracture of dentin adhesively bonded to quartz-fiber reinforced composite

    Melo, Renata M. [Department of Dental Materials and Pronsthodontics at Sao Jose dos Campos Dental Shool, Sao Paulo State University (UNESP), Sao Jose dos Campos, Sao Paulo 12245-820 (Brazil); Rahbar, Nima, E-mail: nrahbar@umassd.edu [Department of Civil and Environmental Engineering, University of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02720 (United States); Soboyejo, Wole [Department of Mechanical and Aerospace Engineering, Princeton Institute of Science and Technology of Materials (PRISM), Princeton University, Princeton, New Jersey 08544 (United States)

    2011-05-10

    The paper presents the results of an experimental study of interfacial failure in a multilayered structure consisting of a dentin/resin cement/quartz-fiber reinforced composite (FRC). Slices of dentin close to the pulp chamber were sandwiched by two half-circle discs made of a quartz-fiber reinforced composite, bonded with bonding agent (All-bond 2, BISCO, Schaumburg) and resin cement (Duo-link, BISCO, Schaumburg) to make Brazil-nut sandwich specimens for interfacial toughness testing. Interfacial fracture toughness (strain energy release rate, G) was measured as a function of mode mixity by changing loading angles from 0 deg. to 15 deg. The interfacial fracture surfaces were then examined using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) to determine the failure modes when loading angles changed. A computational model was also developed to calculate the driving forces, stress intensity factors and mode mixities. Interfacial toughness increased from {approx} 1.5 to 3.2 J/m{sup 2} when the loading angle increases from {approx} 0 to 15 deg. The hybridized dentin/cement interface appeared to be tougher than the resin cement/quartz-fiber reinforced epoxy. The Brazil-nut sandwich specimen was a suitable method to investigate the mechanical integrity of dentin/cement/FRC interfaces.

  7. Dynamic strain distribution measurement and crack detection of an adhesive-bonded single-lap joint under cyclic loading using embedded FBG

    In this study, the dynamic strain distribution measurement of an adhesive-bonded single-lap joint was carried out in a cyclic load test using a fiber Bragg grating (FBG) sensor embedded into the adhesive/adherend interface along the overlap length direction. Unidirectional carbon fiber reinforced plastic (CFRP) substrates were bonded by epoxy resin to form the joint, and the FBG sensor was embedded into the surface of one substrate during its curing. The measurement was carried out with a sampling rate of 5 Hz by the sensing system, based on the optical frequency domain reflectometry (OFDR) throughout the test. A finite element analysis (FEA) was performed for the measurement evaluation using a three-dimensional model, which included the embedded FBG sensor. The crack detection method, based on the longitudinal strain distribution measurement, was introduced and performed to estimate the cracks that occurred at the adhesive/adherend interface in the test. (paper)

  8. Influence of different Er,Cr:YSGG laser parameters on long-term dentin bond strength of self-etch adhesive.

    Yildirim, Tahsin; Ayar, Muhammet Kerim; Yesilyurt, Cemal

    2015-12-01

    The aim of the present study was to evaluate the effects of erbium, chromium: yattrium-scandium-gallium-garnet (Er,Cr:YSGG) laser frequency on microtensile bond strength (μTBS) of a self-etch adhesive to dentin after 15-month water storage. The Er,Cr:YSGG laser can safely be used on dental hard tissue. However, no study has compared the effects of Er,Cr:YSGG laser parameters and aging by water storage on the bonding effectiveness of self-etch adhesives to dentin. Thirty-five bovine teeth were randomly assigned to the following seven groups (n = 5): group I (diamond bur with high-speed handpiece (control)), group II (Er,Cr:YSGG laser 3 W/50 Hz), group III (Er,Cr:YSGG laser 3 W/35 Hz), group IV (Er,Cr:YSGG laser 3 W/20 Hz), group V (Er,Cr:YSGG laser 6 W/50 Hz), group VI (Er,Cr:YSGG laser 6 W/35 Hz), and group VII (Er,Cr:YSGG laser 6 W/20 Hz). Clearfil SE Bond was applied to the prepared dentin, and the composites were placed and cured. Resin-dentin sticks with an approximate cross-sectional area of 0.8 mm(2) were obtained, and bond strength tests were performed at 24 h and 15 months of water storage after bonding. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests (p < 0.05). Laser irradiation resulted in significantly lower bond strengths when compared to bur treating. Fifteen-month water storage reduced bond strength for all groups. There was no significant difference among the effects of different laser frequencies on bond strength. It can be concluded that Er,Cr:YSGG laser used at the tested parameters may alter the dentin bond durability of self-etch adhesive. PMID:26498449

  9. Effect of Casein Phosphopeptide-amorphous Calcium Phosphate Treatment on Microtensile Bond Strength to Carious Affected Dentin Using Two Adhesive Strategies

    Mahmoud Bahari

    2014-09-01

    Full Text Available Background and aims. The aim was to evaluate the effect of casein phosphopeptide–amorphous calcium phosphate (CPP-ACP on microtensile bond strength (μTBS to carious affected dentin (CAD using etch-and-rinse and self-etch ad-hesive systems. Materials and methods. The occlusal surface of 32 human molars with moderate occlusal caries was removed. Infected dentin was removed until reaching CAD and the teeth were randomly divided into two groups based on the Single Bond (SB and Clearfil SE Bond (CSE adhesive systems. Before composite resin bonding, each group was subdivided into three subgroups of ND, CAD and CPP-ACP-treated CAD (CAD-CPP based on the dentin substrate. After dissecting samples to l-mm-thick cross-sections (each subgroup: n = 13, μTBS was measured at a strain rate of 0.5 mm/min. Data was analyzed using two-way ANOVA, independent samples t-test and post-hoc Tukey tests (α=0.05. Results. Bond strength of both adhesive systems to ND was significantly higher than that to CAD (P 0.05. μTBS of CSE to CAD-CPP was higher than that to CAD; however, the difference was not significant (P > 0.05. Significant differences were found between SB and CSE systems only with CAD substrate (P < 0.001. Conclusion. Regardless of the adhesive system used, surface treatment of CAD with CPP-ACP did not have a significant effect on bond strength. However, bond strength to CAD was higher with SB rather than with CSE.

  10. Shear Bond Strength of Self-Etching Adhesive Systems to Er:YAG Laser-Prepared Dentine with and without Pulpal Pressure Simulation

    Brulat, Nathalie; Leforestier, Eric; Rocca, Jean-Paul; Darque-Ceretti, Evelyne; Bertrand, Marie-France

    2008-01-01

    Objective: This study was conducted to study the role of pulpal pressure on the shear bond strength of composite resin bonded to Er:YAG laser-prepared or bur-prepared dentine surfaces using a self-etching adhesive system. Materials and Methods: The occlusal surfaces of 80 human third molars were ground flat to expose the dentine. The dentine was prepared using either a carbide bur or an Er: YAG laser at 350 mJ/pulse and 10 Hz (fluence 44.5 J/cm(2)). Clearfil SE Bond was then applied with or w...

  11. Experimental Investigations on the Influence of Adhesive Oxides on the Metal-Ceramic Bond

    Susanne Enghardt; Gert Richter; Edgar Richter; Bernd Reitemeier; Walter, Michael H

    2015-01-01

    The objective of this study was to test the influence of selected base metals, which act as oxide formers, on the metal-ceramic bond of dental veneer systems. Using ion implantation techniques, ions of Al, In and Cu were introduced into near-surface layers of a noble metal alloy containing no base metals. A noble metal alloy with base metals added for oxide formation was used as a reference. Both alloys were coated with a low-temperature fusing dental ceramic. Specimens without ion implantat...

  12. A Comparative Study of Microleakage on Dental Surfaces Bonded with Three Self-Etch Adhesive Systems Treated with the Er:YAG Laser and Bur

    Sanhadji El Haddar, Youssef; Cetik, Sibel; Bahrami, Babak; Atash, Ramin

    2016-01-01

    Aim. This study sought to compare the microleakage of three adhesive systems in the context of Erbium-YAG laser and diamond bur cavity procedures. Cavities were restored with composite resin. Materials and Methods. Standardized Class V cavities were performed in 72 extracted human teeth by means of diamond burs or Er-YAG laser. The samples were randomly divided into six groups of 12, testing three adhesive systems (Clearfil s3 Bond Plus, Xeno® Select, and Futurabond U) for each method used. Cavities were restored with composite resin before thermocycling (methylene blue 2%, 24 h). The slices were prepared using a microtome. Optical microscope photography was employed to measure the penetration. Results. No statistically significant differences in microleakage were found in the use of bur or laser, nor between adhesive systems. Only statistically significant values were observed comparing enamel with cervical walls (p adhesive restoration procedures, thus constituting an alternative tool for tooth preparation. PMID:27419128

  13. Shear Bond Strength of MDP-Containing Self-Adhesive Resin Cement and Y-TZP Ceramics: Effect of Phosphate Monomer-Containing Primers

    Jin-Soo Ahn

    2015-01-01

    Full Text Available Purpose. This study was conducted to evaluate the effects of different phosphate monomer-containing primers on the shear bond strength between yttria-tetragonal zirconia polycrystal (Y-TZP ceramics and MDP-containing self-adhesive resin cement. Materials and Methods. Y-TZP ceramic surfaces were ground flat with #600-grit SiC paper and divided into six groups (n=10. They were treated as follows: untreated (control, Metal/Zirconia Primer, Z-PRIME Plus, air abrasion, Metal/Zirconia Primer with air abrasion, and Z-PRIME Plus with air abrasion. MDP-containing self-adhesive resin cement was applied to the surface-treated Y-TZP specimens. After thermocycling, a shear bond strength test was performed. The surfaces of the Y-TZP specimens were analyzed under a scanning electron microscope. The bond strength values were statistically analyzed using one-way analysis of variance and the Student–Newman–Keuls multiple comparison test (P<0.05. Results. The Z-PRIME Plus treatment combined with air abrasion produced the highest bond strength, followed by Z-PRIME Plus application, Metal/Zirconia Primer combined with air abrasion, air abrasion alone, and, lastly, Metal/Zirconia Primer application. The control group yielded the lowest results (P<0.05. Conclusion. The application of MDP-containing primer resulted in increased bond strength between Y-TZP ceramics and MDP-containing self-adhesive resin cements.

  14. Identification of the Chemical Bonding Prompting Adhesion of a-C:H Thin Films on Ferrous Alloy Intermediated by a SiCx:H Buffer Layer.

    Cemin, F; Bim, L T; Leidens, L M; Morales, M; Baumvol, I J R; Alvarez, F; Figueroa, C A

    2015-07-29

    Amorphous carbon (a-C) and several related materials (DLCs) may have ultralow friction coefficients that can be used for saving-energy applications. However, poor chemical bonding of a-C/DLC films on metallic alloys is expected, due to the stability of carbon-carbon bonds. Silicon-based intermediate layers are employed to enhance the adherence of a-C:H films on ferrous alloys, although the role of such buffer layers is not yet fully understood in chemical terms. The chemical bonding of a-C:H thin films on ferrous alloy intermediated by a nanometric SiCx:H buffer layer was analyzed by X-ray photoelectron spectroscopy (XPS). The chemical profile was inspected by glow discharge optical emission spectroscopy (GDOES), and the chemical structure was evaluated by Raman and Fourier transform infrared spectroscopy techniques. The nature of adhesion is discussed by analyzing the chemical bonding at the interfaces of the a-C:H/SiCx:H/ferrous alloy sandwich structure. The adhesion phenomenon is ascribed to specifically chemical bonding character at the buffer layer. Whereas carbon-carbon (C-C) and carbon-silicon (C-Si) bonds are formed at the outermost interface, the innermost interface is constituted mainly by silicon-iron (Si-Fe) bonds. The oxygen presence degrades the adhesion up to totally delaminate the a-C:H thin films. The SiCx:H deposition temperature determines the type of chemical bonding and the amount of oxygen contained in the buffer layer. PMID:26135943

  15. Bonding ability of adhesive resins to caries-affected and caries-infected dentin Capacidade de união de resinas adesivas à dentina afetada e infectada por cárie

    Masahiro Yoshiyama; Junichi Doi; Yoshihiro Nishitani; Toshiyuku Itota; Franklin R Tay; Ricardo Marins Carvalho; PASHLEY David H.

    2004-01-01

    Hybridized dentin permits dental treatments that were previously impossible with conventional techniques, opening new frontiers in modern adhesive dentistry. We have investigated the adhesive property of current bonding systems to caries-infected dentin by a microtensile bond strength test (µTBS) and transmission electron microscopy (TEM), and suggested that bonding resin could infiltrate into caries-infected dentin partially to embed carious bacteria within hybrid layers. We have named this ...

  16. THE EFFECTS OF EDGE BANDING THICKNESS OF ULUDAG FIR BONDED WITH SOME ADHESIVES ON WITHDRAWAL STRENGTHS OF BEECH DOWEL PINS IN COMPOSITE MATERIALS

    Şeref Kurt

    2009-11-01

    Full Text Available Composite materials and wooden dowels are being used increasingly in the construction of furniture frames and inner decoration. Yet there is little information available concerning the withdrawal strength of various fasteners, and, in particular, dowels in composite materials edged solid wood edge bandings. The aim of this study was to determine the withdrawal strengths of 6, 8, 10 mm diameter dowels produced from beech with respect to edge of a medium-density fiberboard (MDF or particleboard (PB edged with 5, 10 and 15 mm thickness of solid wood edge banding of uludag fir, bonded with different adhesives. According to TS 4539 standard, the effects of edge banding thickness, dimension of dowels, type of composite materials and type of adhesives used for edge banding on the withdrawal strength were determined. The highest (6.37 N/mm² withdrawal strength was obtained in beech dowels with 8 mm diameter for MDF with 5 mm thickness of solid wood edge banding of uludag fir bonded with D-VTKA adhesive. According to results, if the hole wall and the surface of dowel are smooth then the adhesives give better mechanical adhesion with dowels and composite materials.

  17. Cooperative Research and Development Agreement Final Report for Cooperative Research and Development Agreement Number ORNL93-0237 Adhesive Bonding Technologies for Automotive Structural Composites; TOPICAL

    In 1993, the Oak Ridge National Laboratory (ORNL) entered into a Cooperative Research and Development Agreement (CRADA) with the Automotive Composites Consortium (ACC) to conduct research and development that would overcome technological hurdles to the adhesive bonding of current and future automotive materials. This effort is part of a larger Department of Energy (DOE) program to promote the use of lighter weight materials in automotive structures for the purpose of increasing fuel efficiency and reducing environmental pollutant emissions. In accomplishing this mission, the bonding of similar and dissimilar materials was identified as being of primary importance to the automotive industry since this enabling technology would give designers the freedom to choose from an expanded menu of low mass materials for component weight reduction. The research undertaken under this CRADA addresses the following areas of importance: bulk material characterization, structural fracture mechanics, modeling/characterization, process control and nondestructive evaluation (PC/NDE), manufacturing demonstration, and advanced processing. For the bulk material characterization task, the individual material properties of the adherends and adhesives were characterized. This included generating a database of mechanical and physical properties, after identifying and developing standard test methods to obtain properties. The structural fracture mechanics task concentrated on test development to characterize the fracture toughness of adhesively bonded joints subjected to Mode I, Mode II and mixed-mode conditions. Standard test procedures for quantifying an adhesive/adherend system's resistance to crack growth were developed for use by industry. In the modeling/characterization task, fracture mechanics-based design guidelines and predictive methodologies have been developed which will facilitate iteration on design concepts for bonded joints while alleviating the need for extensive testing

  18. Influence of duration of phosphoric acid pre-etching on bond durability of universal adhesives and surface free-energy characteristics of enamel.

    Tsujimoto, Akimasa; Barkmeier, Wayne W; Takamizawa, Toshiki; Watanabe, Hidehiko; Johnson, William W; Latta, Mark A; Miyazaki, Masashi

    2016-08-01

    The purpose of this study was to evaluate the influence of duration of phosphoric acid pre-etching on the bond durability of universal adhesives and the surface free-energy characteristics of enamel. Three universal adhesives and extracted human molars were used. Two no-pre-etching groups were prepared: ground enamel; and enamel after ultrasonic cleaning with distilled water for 30 s to remove the smear layer. Four pre-etching groups were prepared: enamel pre-etched with phosphoric acid for 3, 5, 10, and 15 s. Shear bond strength (SBS) values of universal adhesive after no thermal cycling and after 30,000 or 60,000 thermal cycles, and surface free-energy values of enamel surfaces, calculated from contact angle measurements, were determined. The specimens that had been pre-etched showed significantly higher SBS and surface free-energy values than the specimens that had not been pre-etched, regardless of the aging condition and adhesive type. The SBS and surface free-energy values did not increase for pre-etching times of longer than 3 s. There were no significant differences in SBS values and surface free-energy characteristics between the specimens with and without a smear layer. The results of this study suggest that phosphoric acid pre-etching of enamel improves the bond durability of universal adhesives and the surface free-energy characteristics of enamel, but these bonding properties do not increase for phosphoric acid pre-etching times of longer than 3 s. PMID:27315775

  19. Microtensile bond strength of current adhesive systems when compared to cohesive strength of sound dentin and a resin-based composite

    Paulo Eduardo Capel Cardoso

    2004-12-01

    Full Text Available Purpose: To evaluate the microtensile bond strength (µTBS to dentin of 4 adhesive systems, the micromorphology of the adhesive/dentin interface and to compare the results to the µTS (cohesive strength of sound dentin and resin composite. Occlusal surfaces of 24 extracted caries-free human molars were cut flat to expose the dentin surface. They were randomly assigned to 4 groups (n = 6: Adper Scotchbond Multi Purpose Plus (MP, Adper Single Bond (SB, Clearfil Protect Bond (CP and Adper Prompt (AP. Adhesive systems were applied and "crowns" were built using Z100. Other 5 human molars were sectioned to obtain square-shaped dentin blocks and 5 resin blocks were built using a composite resin, Z100. After storage in distilled water at 37 °C for 24 h, stick-shaped specimens were obtained for all groups (n = 5 with 0.8 mm² and subjected to µTBS or µTS test. Results were analyzed using One-Way ANOVA and Tukey's test at p 0.05. The lowest result was found for AP (27.4 + 4.7 MPa, although not statistically different from MP. Most specimens (89.4% showed predominant adhesive failure. None of the systems tested reached the µTS values of dentin (108.5 + 9.4 MPa and Z100 (86.5 + 3.6 MPa. Bonded interfaces showed lower µTBS than those µTS of dentin and resin composite blocks. The all-in-one self-etching adhesive had the lowest µTBS.

  20. Systèmes multimatériaux – Assemblage par collage Multimaterial systems – Adhesive bonding

    Zuanna C. Dalla

    2013-11-01

    Full Text Available L'assemblage par collage multimatériaux (métal/composite, métal/verre, métal/plastiques, verre/plastiques… offre de nombreux avantages par rapport aux techniques d'assemblages traditionnelles (pas d'affaiblissement des matériaux par la température, tenues en fatigue et à la corrosion améliorées, esthétisme, étanchéité…. Cependant la qualité et la durabilité à long terme des assemblages collés dépendent d'une bonne conception de ces assemblages : Le choix de préparations de surfaces efficaces, robustes, facilement industrialisables et respectueuses de l'environnement, Le choix d'adhésifs aptes à répondre au cahier des charges fonctionnel de l'assemblage (performances mécaniques, thermiques, chimiques… dont la mise en œuvre est compatible avec les contraintes d'industrialisation (cadences, temps de manipulation des pièces, environnement du poste collage…, Le dessin et le dimensionnement de la liaison de façon à transmettre les efforts mécaniques spécifiés dans la plage de températures de fonctionnement des pièces collées (en tenant compte des dilatations différentielles des matériaux assemblés. Cette démarche sera développée en donnant l'état de l'art actuel et les avancées les plus récentes sur les trois thèmes cités ci-dessus. Adhesive-bonding offers many advantages over traditional joining techniques (no weakening of materials by temperature, required fatigue and improved corrosion resistance, aesthetics, sealing… for multimaterial assembly (metal/composite, metal/glass, metal/plastic, glass/plastic…. However the quality and long term durability of bonded assemblies depend on a correct design of the joint: Choice of eco-efficient surfaces preparations, robust, and easily processed, Choice of adhesive in good adequation with the functional specifications of the assembly (mechanical performance, thermal, chemical… whose implementation is compatible with industrialization constraints

  1. Conventional dual-cure versus self-adhesive resin cements in dentin bond integrity

    Renata Andreza Talaveira da Silva

    2011-08-01

    Full Text Available During post preparation, the root canal is exposed to the oral cavity, and endodontic treatment may fail because of coronal leakage, bacterial infection and sealing inability of the luting cement. OBJECTIVE: this study quantified the interfacial continuity produced with conventional dual-cure and self-adhesive resin cements in the cervical (C, medium (M and apical (A thirds of the root. MATERIAL AND METHODS: Forty single-rooted human teeth were restored using Reforpost # 01 conical glass-fiber posts and different materials (N=10 per group: group AC=Adper™ ScotchBond™ Multi-purpose Plus + AllCem; group ARC=Adper™ ScotchBond™ Multi-purpose Plus + RelyX ARC; group U100=RelyX U100; and group MXC=Maxcem Elite. After being kept in 100% humidity at 37°C for 72 hours, the samples were sectioned parallel to their longitudinal axis and positive epoxy resin replicas were made. The scanning electron micrographs of each third section of the teeth were combined using Image Analyst software and measured with AutoCAD-2002. We obtained percentage values of the interfacial continuity. RESULTS: Interfacial continuity was similar in the apical, medium and cervical thirds of the roots within the groups (Friedman test, p>0.05. Comparison of the different cements in a same root third showed that interfacial continuity was lower in MXC (C=45.5%; M=48.5%; A=47.3% than in AC (C=85.9%, M=81.8% and A=76.0%, ARC (C=83.8%, M=82.4% and A=75.0% and U100 (C=84.1%, M=82.4% and A=77.3% (Kruskal-Wallis test, p<0.05. CONCLUSIONS: Allcem, Rely X ARC and U100 provide the best cementation; cementation was similar among root portions; in practical terms, U100 is the best resin because it combines good cementation and easy application and none of the cements provides complete interfacial continuity.

  2. Push-out bond strength of quartz fibre posts to root canal dentin using total-etch and self-adhesive resin cements

    Kahnamouei, Mehdi A.; Mohammadi, Narmin; Navimipour, Elmira J.; Shakerifar, Maryam

    2011-01-01

    Objectives: Several adhesive systems are available for cementation of fibre posts into the root canal. The aim of the present study was to investigate the push-out bond strengths of quartz fibre posts to root dentin with the use of different total-etch and self-adhesive resin cements. Study Design: Ninety single-rooted human premolars were endodontically treated and standardized post-spaces were prepared. Fibre posts were cemented with different luting agents: total-etch (Nexus NX3, Duo-Link,...

  3. Shear Bond Strength of an Etch-and-rinse Adhesive to Er:YAG Laser- and/or Phosphoric Acid-treated Dentin

    2013-01-01

    Background and aims. Er:YAG laser irradiation has been claimed to improve the adhesive properties of dentin; therefore, it has been proposed as an alternative to acid etching. The aim of this in vitro study was to investigate the shear bond strength of an etch-and-rinse adhesive system to dentin surfaces following Er:YAG laser and/or phosphoric acid etching. Materials and methods. The roots of 75 sound maxillary premolars were sectioned below the CEJ and the crowns were embedded in auto-polym...

  4. A Comparative Study of Microleakage on Dental Surfaces Bonded with Three Self-Etch Adhesive Systems Treated with the Er:YAG Laser and Bur

    Sanhadji El Haddar, Youssef; CETIK, SIBEL; Bahrami, Babak; Atash, Ramin

    2016-01-01

    Aim. This study sought to compare the microleakage of three adhesive systems in the context of Erbium-YAG laser and diamond bur cavity procedures. Cavities were restored with composite resin. Materials and Methods. Standardized Class V cavities were performed in 72 extracted human teeth by means of diamond burs or Er-YAG laser. The samples were randomly divided into six groups of 12, testing three adhesive systems (Clearfil s3 Bond Plus, Xeno® Select, and Futurabond U) for each method used. C...

  5. ADHESION OF AN ENDODONTIC SEALER TO DENTIN AND GUTTA-PERCHA: SHEAR AND PUSH-OUT BOND STRENGTH MEASUREMENTS AND SEM ANALYSIS

    Cleonice Silveira Teixeira; Edson Alfredo; Luis Henrique de Camargo Thomé; Ricardo Gariba-Silva; Yara T. Correa Silva-Sousa; Manoel Damião Sousa-Neto

    2009-01-01

    The use of an adequate method for evaluation of the adhesion of root canal filling materials provides more reliable results to allow comparison of the materials and substantiate their clinical choice. The aims of this study were to compare the shear bond strength (SBS) test and push-out test for evaluation of the adhesion of an epoxy-based endodontic sealer (AH Plus) to dentin and gutta-percha, and to assess the failure modes on the debonded surfaces by means of scanning electron microscopy (...

  6. Effect of chlorhexidine on bonding durability of two self-etching adhesives with and without antibacterial agent to dentin

    Fereshteh Shafiei

    2013-01-01

    Conclusion: Chlorhexidine was capable of diminishing the loss of BS of these adhesives over time. However, considering the negative effect of chlorhexidine on the initial BS, the benefits of chlorhexidine associated with these adhesives cannot possibly be used.

  7. Adhesively bonded joints composed of pultruded adherends: Considerations at the upper tail of the material strength statistical distribution

    Vallee, T.; Keller, Th. [Ecole Polytech Fed Lausanne, CCLab, CH-1015 Lausanne, (Switzerland); Fourestey, G. [Ecole Polytech Fed Lausanne, IACS, Chair Modeling and Sci Comp, CH-1015 Lausanne, (Switzerland); Fournier, B. [CEA SACLAY ENSMP, DEN, DANS, DMN, SRMA, LC2M, F-91191 Gif Sur Yvette, (France); Correia, J.R. [Univ Tecn Lisbon, Inst Super Tecn, Civil Engn and Architecture Dept, P-1049001 Lisbon, (Portugal)

    2009-07-01

    The Weibull distribution, used to describe the scaling of strength of materials, has been verified on a wide range of materials and geometries: however, the quality of the fitting tended to be less good towards the upper tail. Based on a previously developed probabilistic strength prediction method for adhesively bonded joints composed of pultruded glass fiber-reinforced polymer (GFRP) adherends, where it was verified that a two-parameter Weibull probabilistic distribution was not able to model accurately the upper tail of a material strength distribution, different improved probabilistic distributions were compared to enhance the quality of strength predictions. The following probabilistic distributions were examined: a two-parameter Weibull (as a reference), m-fold Weibull, a Grafted Distribution, a Birnbaum-Saunders Distribution and a Generalized Lambda Distribution. The Generalized Lambda Distribution turned out to be the best analytical approximation for the strength data, providing a good fit to the experimental data, and leading to more accurate joint strength predictions than the original two-parameter Weibull distribution. It was found that a proper modeling of the upper tail leads to a noticeable increase of the quality of the predictions. (authors)

  8. Shear bond strength evaluation of resin composite bonded to three different liners: TheraCal LC, Biodentine, and resin-modified glass ionomer cement using universal adhesive: An in vitro study

    Velagala L Deepa

    2016-01-01

    Full Text Available Aims: To compare and evaluate the bonding ability of resin composite (RC to three different liners: TheraCal LC TM (TLC, a novel resin-modified (RM calcium silicate cement, Biodentine TM (BD, and resin-modified glass ionomer cement (RMGIC using an universal silane-containing adhesive and characterizing their failure modes. Materials and Methods: Thirty extracted intact human molars with occlusal cavity (6-mm diameter and 2-mm height were mounted in acrylic blocks and divided into three groups of 10 samples each based on the liner used as Group A (TLC, Group B (BD, and Group C (RMGIC. Composite post of 3 mm diameter and 3 mm height was then bonded to each sample using universal adhesive. Shear bond strength (SBS analysis was performed at a cross-head speed of 1 mm/min. Statistical Analysis Used: Statistical analysis was performed with one-way analysis of variance (ANOVA and post hoc test using Statistical Package for the Social Sciences (SPSS version 20. Results: No significant difference was observed between group A and group C (P = 0.573 while group B showed the least bond strength values with a highly significant difference (P = 0.000. The modes of failure were predominantly cohesive in Groups A and B (TLC and BD while RMGIC showed mixed and adhesive failures. Conclusions: Hence, this present study concludes that the bond strength of composite resin to TLC and RMGIC was similar and significantly higher than that of BD following application of universal adhesive.

  9. Influence of Air Abrasion and Sonic Technique on Microtensile Bond Strength of One-Step Self-Etch Adhesive on Human Dentin

    Baraba Anja

    2015-01-01

    Full Text Available The purpose of this in vitro study was to evaluate the microtensile bond strength of one-step self-etch adhesive to human dentin surface modified with air abrasion and sonic technique and to assess the morphological characteristics of the pretreated dentin surface. The occlusal enamel was removed to obtain a flat dentin surface for thirty-six human molar teeth. The teeth were randomly divided into three experimental groups (n = 12 per group, according to the pretreatment of the dentin: (1 control group, (2 air abrasion group, and (3 sonic preparation group. Microtensile bond strength test was performed on a universal testing machine. Two specimens from each experimental group were subjected to SEM examination. There was no statistically significant difference in bond strength between the three experimental groups (P > 0.05. Mean microtensile bond strength (MPa values were 35.3 ± 12.8 for control group, 35.8 ± 13.5 for air abrasion group, and 37.7 ± 12.0 for sonic preparation group. The use of air abrasion and sonic preparation with one-step self-etch adhesive does not appear to enhance or impair microtensile bond strength in dentin.

  10. The design of an optical sensor arrangement for the detection of oil contamination in an adhesively bonded structure of a liquefied natural gas (LNG) ship

    Liquefied natural gas (LNG) has been widely used as a substitute fuel for commercial purposes. It is transported mainly by LNG ships which have primary and secondary leakage barriers. The former is composed of welded thin stainless steel or invar plates, while the latter is composed of adhesively bonded glass composite or aluminum foil sheets. The role of the secondary barrier is to maintain fluid tightness when the primary barrier fails during the transport of LNG. The tightness of the secondary barrier is dependent on the wetting characteristics between the adhesive and adherend of the bonded structure during bonding operation, which depends much on the contamination on the adherend surface. Therefore, in this work, an optical measuring device of oil contamination on the aluminum surface for the secondary barrier was developed. A transparent oil was used as the contaminant and its effect on the bonding strength was investigated. From the experiments, it has been found that the developed measuring device for oil contamination can be used to detect oil contamination on a large bonding area of the secondary barrier in ship building yards

  11. Mechanical joining and adhesive bonding. Joining processes with new challenges to materials testing; Umformen und Kleben. Fuegeverfahren mit neuen Herausforderungen fuer die Materialpruefung

    Meschut, G. [Volkswagen AG, Wolfsburg (Germany)

    2002-07-01

    This contribution highlights new material combinations in the automotive industry to demonstrate the mutual dependence of joining processes and their implications for the geometric shaping of fasteners in the combined shaping and adhesive bonding joining process. The mechanical properties of joints produced by combined and elementary methods are compared taking into consideration quasi static, oscillating and impact-type loads, and ageing characteristics. The results demonstrate that the combination of mechanical and adhesive bonding methods produces joints of high technological quality which can be implemented in optimised light-weight construction. General information is provided on the use of low-heat hybrid joining technology for project planning of this type of connections in industrial practice. (orig.)

  12. Effect of Casein Phosphopeptide-amorphous Calcium Phosphate Treatment on Microtensile Bond Strength to Carious Affected Dentin Using Two Adhesive Strategies

    Mahmoud Bahari; Siavash Savadi Oskoee; Soodabeh Kimyai; Firoz Pouralibaba; Farrokh Farhadi; Marouf Norouzi

    2014-01-01

    Background and aims. The aim was to evaluate the effect of casein phosphopeptide–amorphous calcium phosphate (CPP-ACP) on microtensile bond strength (μTBS) to carious affected dentin (CAD) using etch-and-rinse and self-etch ad-hesive systems. Materials and methods. The occlusal surface of 32 human molars with moderate occlusal caries was removed. Infected dentin was removed until reaching CAD and the teeth were randomly divided into two groups based on the Single Bond (SB) and Clearfil SE ...

  13. Improving the performance of adhesively bonded double cantilever beam specimen -- an experimental study of brittle adhesives under mode-I loading

    Rudra, Sharan

    Many industrial applications use mechanical fasteners for joining two materials of similar or dissimilar nature. These mechanical fasteners have few limitations such as contact of metal surfaces leading to corrosion which can be overcome by the use of adhesives and hence being replaced rapidly. While numerous global tests have been conducted to measure the interfacial toughness of adhesive joints, limited local tests have been conducted to determine the interfacial traction-separation laws or interfacial cohesive laws. Among the limited local tests in some recent experimental studies, very few studies have considered the effects of the addition of filler material in the adhesive to improve their mechanical properties and also to make it cost effective by decreasing the volume of adhesive used. In this study, the effect of addition of filler material such as basalt fibers in the adhesive layer was studied. Mode-I test was conducted on the adhesive joints; inclusion of basalt fibers of varying length and weight percentages was studied. Adherents used were G-10 laminates while general purpose epoxy was used as the adhesive material. This epoxy was particularly selected as it demonstrated a brittle nature upon curing as ductile adhesives were already studied previously. Also, the viscosity of the EPON 828 resin is low compared to many other resins which would make the homogenous mixing of fibers an easier task. This work mainly concentrated on the improvement of adhesive properties using filler material. Basalt fibers were used as fillers as these fibers have high tensile strength and impact resistance. Neat epoxy was the control specimen and tests were performed with epoxy containing basalt fibers with 2%, 5% and 10% weight fractions that also have varying length of fibers. The fiber lengths which were considered were 0.4mm and 0.15mm. Mode-I tests were conducted on several samples with glass fiber composite laminates (GFRP) as adherents which were of similar

  14. Tensile bond srength between composite resin using different adhesive systems
    Avaliação da resistência à ruptura por tração entre resina composta e diversos adesivos dentinários

    Patrícia Dias; Raul Santos de Sá; Jorge Augusto César; Guilherme Augusto de Barros Nolasco; Fátima Cristina de Sá

    2002-01-01

    The aim of this study was evaluate the tensile bond strength (TBS) among nine adhesive systems and one composite resin. The groups were made as follows: Single Bond/3M (G1), Etch & Prime 3.0 /Degussa (G2), Bond 1/Jeneric/Pentron (G3), Prime & Bond 2.1/Dentsply (G4), OptiBond FL/Kerr (G5), Stae/SDI (G6), Snap Bond/ Copalite-Cooley & Cooley (G7), Prime & Bond NT/Dentsply (G8), Scotchbond Multi Purpose Plus/3M (G9). The control group (G10) was made only with the composite resin (Z100/3M). One hu...

  15. Effect of Polar Environments on the Aluminum Oxide Shell Surrounding Aluminum Particles: Simulations of Surface Hydroxyl Bonding and Charge.

    Padhye, Richa; Aquino, Adelia J A; Tunega, Daniel; Pantoya, Michelle L

    2016-06-01

    Density functional theory (DFT) calculations were performed to understand molecular variations on an alumina surface due to exposure to a polar environment. The analysis has strong implications for the reactivity of aluminum (Al) particles passivated by an alumina shell. Recent studies have shown a link between the carrier fluid used for Al powder intermixing and the reactivity of Al with fluorine containing reactive mixtures. Specifically, flame speeds show a threefold increase when polar liquids are used to intermix aluminum and fluoropolymer powder mixtures. It was hypothesized that the alumina lattice structure could be transformed due to hydrogen bonding forces exerted by the environment that induce modified bond distances and charges and influence reactivity. In this study, the alumina surface was analyzed using DFT calculations and model clusters as isolated systems embedded in polar environments (acetone and water). The conductor-like screening model (COSMO) was used to mimic environmental effects on the alumina surface. Five defect models for specific active -OH sites were investigated in terms of structures and vibrational -OH stretching frequencies. The observed changes of the surface OH sites invoked by the polar environment were compared to the bare surface. The calculations revealed a strong connection between the impact of carrier fluid polarity on the hydrogen bonding forces between the surface OH sites and surrounding species. Changes were observed in the OH characteristic properties such as OH distances (increase), atomic charges (increase), and OH stretching frequencies (decrease); these consequently improve OH surface reactivity. The difference between medium (acetone) and strong (water) polar environments was minimal in the COSMO approximation. PMID:27175545

  16. Comparative evaluation of shear bond strength of two self-etching adhesives (sixth and seventh generation on dentin of primary and permanent teeth: An in vitro study

    Yaseen S

    2009-03-01

    Full Text Available Aim: The present study was undertaken to compare and evaluate shear bond strength of two self-etching adhesives (sixth and seventh generation on dentin of primary and permanent teeth. Materials and Methods: Flat dentin surface of 64 human anterior teeth (32 primary and 32 permanent divided into four groups of 16 each. Groups A and C were treated with Contax (sixth generation, while groups B and D were treated with Clearfil S3 (seventh generation. A teflon mold was used to build the composite (Filtek Z-350 cylinders on the dentinal surface of all the specimens. Shear bond strength was tested for all the specimens with an Instron Universal Testing Machine. Data were statistically analyzed using one-way ANOVA for multiple group comparison, followed by student′s unpaired ′t′ test for group-wise comparison. Results: There was no statistically significant difference in shear bond strength among the study groups except that primary teeth bonded with Contax exhibited significantly lesser shear bond strength than permanent teeth bonded with Clearfil S3. Conclusion: This study revealed that Clearfil S3 could be of greater advantage in pediatric dentistry than Contax because of its fewer steps and better shear bond strength in dentin of both primary and permanent teeth.

  17. Resistência de união à dentina de quatro sistemas adesivos Bond strength of four adhesive systems to dentin

    Marcela Rocha de Oliveira Carrilho

    2002-09-01

    Full Text Available O objetivo do presente estudo foi avaliar a resistência adesiva de quatro sistemas adesivos, composicionalmente diferentes, aplicados à dentina humana. Doze dentes terceiros molares humanos tiveram o esmalte oclusal removido para exposição de uma superfície plana de dentina, na qual foram realizados os procedimentos de adesão. Os dentes foram aleatoriamente divididos em quatro grupos, considerando-se o sistema adesivo e a resina composta a serem empregados: Grupo 1 - Single Bond + P60 (SB; Grupo 2 - Bond 1 + Surefil (B1; Grupo 3 - Prime & Bond NT + Alert (NT e Grupo 4 - Prime & Bond 2.1 + TPH (2.1. Após 24 h de armazenagem em água destilada a 37ºC, os dentes foram seccionados, longitudinalmente, em cortes perpendiculares entre si, para que fossem obtidos espécimes em formato de um paralelogramo com secção transversal retangular de 0,8 mm² de área e 10 mm de comprimento, em média. Os espécimes foram submetidos ao teste de microtração. A análise de variância (alfa = 0,05 demonstrou não haver diferença significante entre os valores médios de resistência obtidos pelos quatro adesivos, embora a análise dos espécimes que sofreram fratura precoce tenha evidenciado menor sensibilidade para o sistema SB.The purpose of the present study was to evaluate the bond strength of four adhesive systems to dentin. Twelve human third molars had their occlusal enamel removed in order to expose a flat dentinal surface, on which the adhesive procedures were carried out. The teeth were divided into four groups, according to the employed adhesive system and composite resin: Group 1 - Single Bond + P60 (SB; Group 2 - Bond 1 + Surefil (B1; Group 3 - Prime & Bond NT + Alert (NT; and Group 4 - Prime & Bond 2.1 + TPH (2.1. After 24 h in distilled water at 37ºC, the teeth were longitudinally sectioned in two perpendicular directions in order to obtain parallelogram-shaped specimens with a cross-sectional area of 0.8 mm² and 10 mm of length, on the

  18. Evaluation of the tensile bond strength of an adhesive system self-etching in dentin irradiated with Er:YAG laser

    Since Buonocore (1955), several researchers have been seeking for the best adhesive system and treatment for the enamel and dentin surfaces. The use of the acid has been presented as one of the best techniques of dentin conditioning , because this promotes the removal of the 'smear layer and exhibition of dentinal structure, for a best penetration and micro- retention of the adhesive system. However, some conditioning methods have been appearing in the literature, for the substitution or interaction with the acid substances, as the laser. The objective of this work is to evaluate the tensile bond strength of the adhesive system self-etching' associated to a composed resin, in dentin surfaces conditioned with the Er:YAG laser. For this study, freshly extracted human teeth were used and in each one the dentinal surfaces , which were treated with three sandpapers of different granulations (120,400,600), to obtain a standard of the smear layer, before the irradiation of the laser and of the restoring procedure. After these procedures the specimens were storage in distilled water at 37 deg C for 24 hours. Soon after, they were submitted to the tensile strength test .After analyzing the results, we can concluded that the use of the Er:YAG laser can substitute the drill without the need of conditioning, when using the adhesive system 'self-etching' in the dentinal surfaces because there was a decline in the strength of adhesion in the groups conditioned with the laser. (author)

  19. Fabrication of microfluidic chips using lithographic patterning and adhesive bonding of the thick negative photoresist AZ 125 nXT

    Knoll, Thorsten; Bergmann, Andreas; Nußbaum, Dominic

    2015-05-01

    In this work, for the first time the negative photoresist AZ 125 nXT was used for the fabrication of a microfluidic chip. Usually, fabrication of microfluidic devices on the basis of silicon or glass substrates is done by using the epoxy-based negative photoresist SU-8 or other thick film polymer materials. The suitability of SU-8 for various microfluidic applications has been shown in the fields of bioanalytic devices, lab-on-chip systems or microreaction technology. However, processing is always a very challenging task with regard to the adaptation of process parameters to the individual design and required functionality. Now, the AZ 125 nXT allows for the fabrication of structures in a wide thickness range with only one type of viscosity. In contrast to SU-8, the AZ 125 nXT is fully cross-linked during UV exposure and does not require a time-consuming post-exposure bake. 90 μm deep microfluidic channels were defined by lithographic patterning of AZ 125 nXT. Sealing of the open microfluidic channels was performed by a manual adhesive bonding process at a temperature of 100 °C. The fluidic function was successfully tested with flow rates up to 20 ml/min by means of a microfluidic edge connector. Long term stability and chemical resistance of the fabricated microfluidic channels will be investigated in the near future. The presented work shows the potential of AZ 125 nXT as a possible alternative to SU-8 for the fabrication of microfluidic chips.

  20. A simple beam model to analyse the durability of adhesively bonded tile floorings in presence of shrinkage

    S. de Miranda

    2014-07-01

    Full Text Available A simple beam model for the evaluation of tile debonding due to substrate shrinkage is presented. The tile-adhesive-substrate package is modeled as an Euler-Bernoulli beam laying on a two-layer elastic foundation. An effective discrete model for inter-tile grouting is introduced with the aim of modelling workmanship defects due to partial filled groutings. The model is validated using the results of a 2D FE model. Different defect configurations and adhesive typologies are analysed, focusing the attention on the prediction of normal stresses in the adhesive layer under the assumption of Mode I failure of the adhesive.

  1. Silica-shell encapsulation and adhesion of VO2 nanowires to glass substrates: integrating solution-derived VO2 nanowires within thermally responsive coatings

    Pelcher, Kate E.; Crawley, Matthew R.; Banerjee, Sarbajit

    2014-09-01

    The binary vanadium oxide VO2 undergoes a reversible insulator—metal phase transition in response to increasing temperature accompanied by an orders of magnitude alteration of optical transmittance; the low-temperature monoclinic phase of VO2 is infrared-transmissive, whereas the high-temperature rutile phase is infrared-reflective. This remarkable property portends applications in thermally responsive spectral mirrors that can modulate infrared transmittance as a function of temperature. Using a modified Stöber process, we demonstrate the constitution of conformal SiO2 shells around the VO2 nanowires. The SiO2 shells enhance the robustness of the VO2 nanowires towards thermal oxidation; the thickness of the shells is observed to depend on the reaction time. Notably, the deposition of conformal shells does not deleteriously impact the metal—insulator transitions of the VO2 nanowire cores. A modification of this approach allows for the VO2 nanowires to be embedded within a SiO2 matrix bonded to glass. The applied coatings are strongly adhered to glass as evaluated using standardized ASTM methods. The coatings exhibit promising thermochromic response and attenuate transmission of near-infrared radiation with increasing temperature.

  2. Silica-shell encapsulation and adhesion of VO2 nanowires to glass substrates: integrating solution-derived VO2 nanowires within thermally responsive coatings

    The binary vanadium oxide VO2 undergoes a reversible insulator—metal phase transition in response to increasing temperature accompanied by an orders of magnitude alteration of optical transmittance; the low-temperature monoclinic phase of VO2 is infrared-transmissive, whereas the high-temperature rutile phase is infrared-reflective. This remarkable property portends applications in thermally responsive spectral mirrors that can modulate infrared transmittance as a function of temperature. Using a modified Stöber process, we demonstrate the constitution of conformal SiO2 shells around the VO2 nanowires. The SiO2 shells enhance the robustness of the VO2 nanowires towards thermal oxidation; the thickness of the shells is observed to depend on the reaction time. Notably, the deposition of conformal shells does not deleteriously impact the metal—insulator transitions of the VO2 nanowire cores. A modification of this approach allows for the VO2 nanowires to be embedded within a SiO2 matrix bonded to glass. The applied coatings are strongly adhered to glass as evaluated using standardized ASTM methods. The coatings exhibit promising thermochromic response and attenuate transmission of near-infrared radiation with increasing temperature. (paper)

  3. Eight-year randomized clinical evaluation of Class II nanohybrid resin composite restorations bonded with a one-step self-etch or a two-step etch-and-rinse adhesive

    van Dijken, Jan WV; Pallesen, Ulla

    2015-01-01

    -based nanohybrid resin composite (Ceram X) bonded with either a one-step self-etch adhesive (Xeno III) or a control two-step etch-and-rinse adhesive (Excite). The 165 restorations were evaluated using slightly modified United States Public Health Services (USPHS) criteria at baseline and then yearly during 8 years...

  4. Bonding effectiveness of self-adhesive and conventional-type adhesive resin cements to CAD/CAM resin blocks. Part 2: Effect of ultrasonic and acid cleaning.

    Kawaguchi, Asuka; Matsumoto, Mariko; Higashi, Mami; Miura, Jiro; Minamino, Takuya; Kabetani, Tomoshige; Takeshige, Fumio; Mine, Atsushi; Yatani, Hirofumi

    2016-01-01

    The present study assessed the effect of ultrasonic and acid cleaning on resin cement bonding to CAD/CAM resin blocks. One of two resin cements, PANAVIA V5 (PV5) or PANAVIA SA CEMENT HANDMIX (PSA), were bonded to one of 24 CAD/CAM blocks (KATANA AVENCIA BLOCK). Each cement group was divided into four subgroups: no cleaning (Ctl), ultrasonic cleaning (Uc), acid cleaning (Ac) and Uc+Ac. Micro-tensile bond strengths (µTBSs) were measured immediately and 1, 3, and 6 months after water storage. Block surfaces after each treatment were analyzed by scanning electron microscopy. Analysis of variance revealed a statistically significant effect for the parameters 'surface treatment' (psandblasting was effective in removing residual alumina particles, it did not affect the long-term bonding durability with non-contaminated CAD/CAM resin blocks. PMID:26830822

  5. Effect of Water Storage on the Micro-shear Bond Strength of Two Self-etch Adhesives to Enamel and Dentin

    Z. Jaberi Ansari

    2007-06-01

    Full Text Available Objective: This study evaluated the influence of storage time on micro-shear bond strength of two self-etching materials to enamel and dentin.Materials and Methods: Human third molar teeth were sectioned to 1.5 mm thick beams and randomly divided into 2 groups. In group I, SE Bond and in group II, Tri-S Bond was used to bond a composite rod (AP-X to each treated surface. Specimens were prepared according to manufacturer instructions. Each group was further divided into three subgroups according to water storage time; 1 day, 6 and 12 months. Microshear bond strengths were determined under a crosshead speed of 1mm/min using a universal testing machine and expressed in MPa. Data was statistically analyzed by ANOVA and Dunnett post hoc test.Results: Micro-shear bond strength of two adhesives to enamel and dentin showed a slight but not significant decrease over time (P>0.5. After one day, the mean bond strength of enamel in groups I and II were 39.47 and 34.65 MPa and in dentin were 45.20 and 36.0 MPa respectively. There was no statistically significant differencebetween two materials (P=0.190, P=0.082. After six months the bond strength in group I and II was 35.93 and 35.18 MPa for enamel, and 38.27and 35.19 MPa for dentin respectively, these differences was not statistically significant (P=0.520, P=0.179.After one year, the bond strength of enamel in groups I and II, were 34.47and 29.91MPa, and in dentin were 33.86 and 32.53 MPa respectively which was not statistically significant (P=0.609, P=0.991.Conclusion: The micro-shear bond strength of both adhesives to enamel and dentin decreased slightly over time; however these decreases were not statistically significant.

  6. Microleakage of bonded amalgam restorations using different adhesive agents with dye under vacuum: An in vitro study

    Abhishek Parolia

    2011-01-01

    Clinical Significance: Bonded amalgam restorations prevent over-preparation and reduce the tooth flexure. GIC type I under amalgam provides chemical bonding in between amalgam and tooth structure and thus reduces the microleakage.

  7. A Semi-Analytical Method for Determining the Energy Release Rate of Cracks in Adhesively-Bonded Single-Lap Composite Joints

    Yang, Charles; Sun, Wenjun; Tomblin, John S.; Smeltzer, Stanley S., III

    2007-01-01

    A semi-analytical method for determining the strain energy release rate due to a prescribed interface crack in an adhesively-bonded, single-lap composite joint subjected to axial tension is presented. The field equations in terms of displacements within the joint are formulated by using first-order shear deformable, laminated plate theory together with kinematic relations and force equilibrium conditions. The stress distributions for the adherends and adhesive are determined after the appropriate boundary and loading conditions are applied and the equations for the field displacements are solved. Based on the adhesive stress distributions, the forces at the crack tip are obtained and the strain energy release rate of the crack is determined by using the virtual crack closure technique (VCCT). Additionally, the test specimen geometry from both the ASTM D3165 and D1002 test standards are utilized during the derivation of the field equations in order to correlate analytical models with future test results. The system of second-order differential field equations is solved to provide the adherend and adhesive stress response using the symbolic computation tool, Maple 9. Finite element analyses using J-integral as well as VCCT were performed to verify the developed analytical model. The finite element analyses were conducted using the commercial finite element analysis software ABAQUS. The results determined using the analytical method correlated well with the results from the finite element analyses.

  8. A Comparative Study of Microleakage on Dental Surfaces Bonded with Three Self-Etch Adhesive Systems Treated with the Er:YAG Laser and Bur

    Youssef Sanhadji El Haddar

    2016-01-01

    Full Text Available Aim. This study sought to compare the microleakage of three adhesive systems in the context of Erbium-YAG laser and diamond bur cavity procedures. Cavities were restored with composite resin. Materials and Methods. Standardized Class V cavities were performed in 72 extracted human teeth by means of diamond burs or Er-YAG laser. The samples were randomly divided into six groups of 12, testing three adhesive systems (Clearfil s3 Bond Plus, Xeno® Select, and Futurabond U for each method used. Cavities were restored with composite resin before thermocycling (methylene blue 2%, 24 h. The slices were prepared using a microtome. Optical microscope photography was employed to measure the penetration. Results. No statistically significant differences in microleakage were found in the use of bur or laser, nor between adhesive systems. Only statistically significant values were observed comparing enamel with cervical walls (p<0.001. Conclusion. It can be concluded that the Er:YAG laser is as efficient as diamond bur concerning microleakage values in adhesive restoration procedures, thus constituting an alternative tool for tooth preparation.

  9. The Effects of Temperature, Humidity and Aircraft Fluid Exposure on T800H/3900-2 Composites Bonded with AF-555M Adhesive

    Miner, Gilda A.; Hou, Tan-Hung; Lowther, Sharon E.; Thibeault, Sheila A.; Connell, John W.; Blasini, Sheila Roman

    2010-01-01

    Fiber reinforced resin matrix composites and structural adhesives have found increased usage on commercial and military aircraft in recent years. Due to the lack of service history of these relatively new material systems, their long-term aging performance has not been well established. In this study, single lap shear specimens (SLS) were fabricated by secondary bonding of Scotch-Weld(TradeMark) AF-555M between pre-cured adherends comprised of T800H/3900-2 uni-directional laminates. The adherends were co-cured with wet peel-ply for surface preparation. Each bond-line of the SLS specimen was measured to determine thickness and inspected visually using an optical microscope for voids. A three-year environmental aging plan for the SLS specimens at 82 C (180 F) and 85% relative humidity was initiated. SLS strengths were measured for both controls and aged specimens at room temperature and 82 C. The effect of this exposure on lap shear strength and failure modes to date is reported. In addition, the effects of water, saline water, deicing fluid, JP-5 jet fuel and hydraulic fluid on both the composite material and the adhesive bonds were investigated. The up to date results on the effects of these exposures will be discussed.

  10. A comparative clinical study of the failure rate of orthodontic brackets bonded with two adhesive systems: conventional and self-etching primer (SEP

    Gladys Cristina Dominguez

    2013-04-01

    Full Text Available OBJECTIVE: This study compared the clinical performance of orthodontic brackets bonded with Transbond adhesive paste after two priming systems: a two-stage conventional system (acid etching + Transbond XT adhesive primer and a singlestage self-etching primer (SEP (Transbond Plus. METHODS: The sample comprised 480 metal brackets bonded to the teeth of 24 consecutive patients treated for 36 to 48 months. A split-mouth design was used for bonding, and both systems were used in each patient. Bracket failure rates for each system were analyzed; and failure causes as reported by the patients and the quadrant of teeth for which brackets failed were recorded. RESULTS: The conventional system group had a failure rate of 5.41%, whereas the rate for SEP was 4.58%. In this group, there were 5 failures (38.4% in the right maxillary quadrant, 2 (15.4% in the left maxillary quadrant, 4 (30.8% in the right mandibular quadrant, and 2 (15.4% in the left mandibular quadrant. In the SEP group, there were 4 (36.4% failures in the right maxillary quadrant, 1 (9% in the left maxillary quadrant, 3 (27.3% in the right mandibular quadrant, and 3 (27.3% in the left mandibular quadrant. Results of descriptive statistical analysis and odds ratio did not show any significant differences between rates (p = 0.67. CONCLUSION: The clinical efficiency of SEP was similar to that of the conventional system.

  11. Comparison of shear bond strength of self-etching fluoride releasing adhesives with and without pumice prophylaxis

    V R Shobbana Devi

    2015-01-01

    Conclusions: Fluoride releasing adhesives combined with antibacterial monomer can play a vital role in reducing white spot lesions by enhancing the cariostatic effect especially in noncompliant\\medically compromised patients.

  12. Effect of different blood contaminated adherent surface treatments on shear bond strength of compomer and composite resin to dentin, using a self etching adhesive

    Mortazavi V.

    2005-06-01

    Full Text Available Statement of Problem: Blood contamination is a common problem in dentistry that can decrease bond strength dramatically which may be affected by methods of decontamination as well. Purpose: The aim of this study was to evaluate and compare the influence of blood contamination on shear bond strength of composite and compomer to dentin using Prompt L-Pop as an adhesive system. Also, to assess the effectiveness of different surface treatments on the bond strength. Materials and Methods: In this experimental study, 120 molar teeth were sectioned to provide flat occlusal dentinal surfaces. Specimens were embedded in acrylic resin with the flat surface exposed. The dentinal expose surfaces were polished to 600 grit. The teeth were randomly divided into five groups of twelve specimens (F1–F5 for compomer material and five other groups (Z1- Z5 for composite resin. After application of Promt L-Pop to dentinal surfaces of specimens, the surfaces in all groups, except for F1 and Z1, (as controls were contaminated with human blood and then one of the following surface treatments was applied. Groups F2 and Z2 without any treatment, groups F3 and Z3 rinsing with water, groups F4 and Z4 rinsing with water and reapplication of adhesive, groups F5 and Z5 rinsing with NaOCl and using Prompt L-Pop again. Restorative materials were applied to treated surfaces using plastic molds. After thermocycling, shear bond strengths, mode of failures and morphology of dentin-material interfaces were evaluated. The data were statistically analyzed using Factorial analysis of Variance, One-Way ANOVA, Duncan, T-student and Chi-Square tests with P<0.05 as the limit of significance. Results: Compomer showed statistically significant higher bond strength in comparison to composite (P<0.001. Duncan test showed significant differences between all compomer groups, except between groups F4 and F5, and between all composite groups except for groups Z1 and Z4 and for groups Z2 and Z3

  13. Effect of sodium ascorbate on the bond strength of all-in-one adhesive systems to NaOCl-treated dentin

    Ebrahimi Chaharom, Mohammad Esmaeel; Kimyai, Soodabeh; Mohammadi, Narmin; Oskoee, Parnian Alizadeh; Daneshpuy, Mehdi; Bahari, Mahmood

    2015-01-01

    Background Ascorbic acid and its salts are low-toxicity products, which are routinely used in food industries as antioxidants. The aim of the present study was to evaluate the effect of 10% sodium ascorbate on the bond strength of two all-in-one adhesive systems to NaOCl-treated dentin. Material and Methods After exposing the dentin on the facial surface of 90 sound human premolars and mounting in an acrylic resin mold, the exposed dentin surfaces were polished with 600-grit SiC paper under r...

  14. Composite shells with interlaminar imperfections

    Wozniak, Czeslaw; Wozniak, Margaret

    1993-01-01

    In this contribution the effect of interlaminar initial imperfections on a composite shell behavior is investigated. The constitutive equations for shells with initial interlaminar bonding imperfections are obtained.

  15. Bonding effectiveness of self-adhesive and conventional-type adhesive resin cements to CAD/CAM resin blocks. Part 1: Effects of sandblasting and silanization.

    Higashi, Mami; Matsumoto, Mariko; Kawaguchi, Asuka; Miura, Jiro; Minamino, Takuya; Kabetani, Tomoshige; Takeshige, Fumio; Mine, Atsushi; Yatani, Hirofumi

    2016-01-01

    The present study assessed the effect of sandblasting and silanization on resin cement bond strengths to CAD/CAM resin blocks. Twenty four blocks (KATANA AVENCIA BLOCK) were divided into two resin cement groups (PANAVIA V5 [PV5] and PANAVIA SA CEMENT HANDMIX [PSA]), and further divided into four subgroups representing different surface treatment methods: no treatment (Ctl), silanization (Si), sandblasting (Sb), and Sb+Si. After resin application, microtensile bond strengths (μTBSs) were measured immediately, 1, 3 and 6 months after water storage. In addition, surfaces resulting from each of the treatment methods were analyzed by scanning electron microscopy (SEM). Three-way analysis of variance revealed a statistically significant effect for the parameters 'surface treatment' (psandblasting roughened surfaces. PMID:26830821

  16. Surface pH and bond strength of a self-etching primer/adhesive system to intracoronal dentin after application of hydrogen peroxide bleach with sodium perborate.

    Elkhatib, Hanadi; Nakajima, Masatoshi; Hiraishi, Noriko; Kitasako, Yuichi; Tagami, Junji; Nomura, Satoshi

    2003-01-01

    This study compared the dentin bond strength of a self-etching primer/adhesive system with dentin surface pH with or without bleaching and observed the morphological changes in bleached dentin treated with a self-etching primer. Dentin disks were prepared from the coronal-labial region of 32 human anterior teeth. The pulpal surfaces of the dentin disks were polished with 600-grit SiC paper under running water. The dentin surfaces on all specimens were bleached with a mixture of 30% hydrogen peroxide and sodium perborate in 100% humidity at 37 degrees C for one week. The bleaching agent was then rinsed off with water for 5, 15 or 30 seconds. All specimens were stored in water at 37 degrees C. Half of the five-second rinsing specimens were stored in water for an additional week. Dentin surface pH with or without bleaching was examined using a pH-imaging microscope (SCHEM-100). A self-etching primer/adhesive system (Clearfil SE Bond) was applied to bleached or unbleached dentin according to the manufacturer's instructions. After 24-hour water storage, the bonded specimens were prepared for microtensile testing. Microtensile bond strength (microTBS) to dentin was measured using a universal-testing machine (EZ test, Shimadzu, Japan) at a crosshead speed of 1.0 mm/minute. Data were analyzed by one-way ANOVA and Scheffe's test (alpha=0.05). The pH values of the dentin surfaces of the 5 and 15 second rinsing groups were significantly higher than the control group (pwater storage groups had similar surface pH values to the control group (pwater storage, the microTBS returned to the control group. The application of a bleaching agent increased the pH value of the dentin surface and decreased the bond strength of the self-etching primer/adhesive system. One-week water storage after bleaching recovered the surface pH and the microTBS to dentin. PMID:14531606

  17. Tensile bond strength of self-etching versus total-etching adhesive systems under different dentinal substrate conditions Resistência de união à tração de sistemas adesivos autocondicionantes versus de condicionamento total, em diferentes condições de substrato dentinário

    Alexandre Henrique Susin; Walison Arthuso Vasconcellos; José Roberto Cury Saad; Osmir Batista de Oliveira Junior

    2007-01-01

    The use of acid etchants to produce surface demineralization and collagen network exposure, allowing adhesive monomers interdiffusion and consequently the formation of a hybrid layer, has been considered the most efficient mechanism of dentin bonding. The aim of this study was to compare the tensile bond strength to dentin of three adhesive systems, two self-etching ones (Clearfil SE Bond - CSEB and One Up Bond F - OUBF) and one total-etching one (Single Bond - SB), under three dentinal subst...

  18. Strength and failure analysis of inverse Z joints bonded with Vinylester Atlac 580 and Flexo Tix adhesives

    Adin, Hamit [Univ. of Batman, Batman (Turkmenistan); Turgut, Aydin [University of Firat, Elazig (Turkmenistan)

    2012-11-15

    In this study, the tensile strength and failure loads of the inverse Z joints were analyzed both experimentally and numerically by using two adhesives with different properties under a tensile load. Vinylester Atlac 580 and Flexo Tix were used as adhesives and the joints were prepared with two different composite materials. Initially, the mechanical properties of the adhesives were specified using bulk specimens. Then, the stress analyses were performed using three dimensional finite element method (3 D FEM) via Ansys (V.10.0.1). The experimental results were compared with the numerical results and they were found quite reasonable. According to the test results, it can be seen that when the adherend thickness is increased, the stress increases as well. The most appropriate value of the adherend thickness is identified as t = 5 mm. Furthermore, it was observed that the lowest failure load was obtained at t = 3 mm the thickness for each specimen.

  19. Adhesion of Cercaria (Larva of Helminth Parasites to Host by Lectins- Carbohydrates Bonds as a Model for Evaluation of Schistosoma Entrance Mechanisms in Cercarial Dermatitis

    A Farahnak

    2008-07-01

    Full Text Available Background: Cercariae (larva of helminth parasites are covered by a thick glycocalyx coat, which serves as an osmotic protection during their free existence, and contain carbohydrates conjugated as glycoproteins, glycolipids and mucopolysaccharides. Although, limited studies have been made on life cycle of cercariae from fresh water snails, however, carbohydrate studies on cercariae have not been done in Iran so far. This study was made to determine the cercariae specifications from Lymnaea gedrosiana and evaluation of surface carbohydrates as receptors for host lectins in a host-parasite relationship system as a model in human schistosomiasis including cercarial dermatitis in Khuzestan Province. Methods: For this purpose, snails were collected from Dezful region in Khuzestan Province and cercariae were obtained by shedding method and identified by valuable keys. Experimental infection was established in the Culex pipiens (Culicidae mosquitoes larvae for further identification and mode of adhesion. To detect the mode of adhesion, surface carbohydrates of cercariae were detected by lentil (Lens culinaris lectins. Results: Examined snails were infected with xiphidiocerceria of trematodes and metacercariae were obtained from Culex pipiens. Also, Mannose monosaccharides- CH2OH (CHOH 4CHO - were detected particularly on the glands of cercariae. Conclusion: Adhesion of cercariae to their host by lectins-carbohydrates bonds is the first stage of host-parasite relationship. This phenomenon could be happened for animal schistosome's cercaria in cercarial dermatitis.

  20. Thermal Characterization of Adhesive

    Spomer, Ken A.

    1999-01-01

    The current Space Shuttle Reusable Solid Rocket Motor (RSRM) nozzle adhesive bond system is being replaced due to obsolescence. Down-selection and performance testing of the structural adhesives resulted in the selection of two candidate replacement adhesives, Resin Technology Group's Tiga 321 and 3M's EC2615XLW. This paper describes rocket motor testing of these two adhesives. Four forty-pound charge motors were fabricated in configurations that would allow side by side comparison testing of the candidate replacement adhesives and the current RSRM adhesives. The motors provided an environment where the thermal performance of adhesives in flame surface bondlines was compared. Results of the FPC testing show that: 1) The phenolic char depths on radial bond lines is approximately the same and vary depending on the position in the blast tube regardless of which adhesive was used; 2) The adhesive char depth of the candidate replacement adhesives is less than the char depth of the current adhesives; 3) The heat-affected depth of the candidate replacement adhesives is less than the heat-affected depth of the current adhesives; and 4) The ablation rates for both replacement adhesives are slower than that of the current adhesives.

  1. Shear Bond Strength of an Etch-and-rinse Adhesive to Er:YAG Laser- and/or Phosphoric Acid-treated Dentin.

    Davari, Abdolrahim; Sadeghi, Mostafa; Bakhshi, Hamid

    2013-01-01

    Background and aims. Er:YAG laser irradiation has been claimed to improve the adhesive properties of dentin; therefore, it has been proposed as an alternative to acid etching. The aim of this in vitro study was to investigate the shear bond strength of an etch-and-rinse adhesive system to dentin surfaces following Er:YAG laser and/or phosphoric acid etching. Materials and methods. The roots of 75 sound maxillary premolars were sectioned below the CEJ and the crowns were embedded in auto-polymerizing acrylic resin with the buccal surfaces facing up. The buccal surfaces were ground using a diamond bur and polished until the dentin was exposed; the samples were randomly divided into five groups (n=15) according to the surface treatment: (1) acid etching; (2) laser etching; (3) laser etching followed by acid etching; (4) acid etching followed by laser etching and (5) no acid etching and no laser etching (control group). Composite resin rods (Point 4, Kerr Co) were bonded to treated dentin surfaces with an etch-and-rise adhesive system (Optibond FL, Kerr Co) and light-cured.After storage for two weeks at 37°C and 100% humidity and then thermocycling, bond strength was measured with a Zwick Universal Testing Machine at a crosshead speed of 1 mm/min. Data was analyzed using parametric and non-parametric tests (P<0.05). Results. Mean shear bond strength for acid etching (20.1±1.8 MPa) and acid+laser (15.6±3.5 MPa) groups were significantly higher than those for laser+acid (15.6±3.5 MPa), laser etching (14.1±3.4 MPa) and control (8.1±2.1 MPa) groups. However, there were no significant differences between acid etching and acid+laser groups, and between laser+acid and laser groups. Conclusion. When the cavity is prepared by bur, it is not necessary to etch the dentin surface by Er:YAG laser following acid etching and acid etching after laser etching. PMID:23875083

  2. Bonding silicones with epoxies

    Tira, J.S.

    1980-01-01

    It is shown that silicones, both room temperature vulcanizing (RTV) and millable rubber (press cured) can be successfully bonded to other materials using plasma treatment and epoxy adhesives. The plasma treatment using dry air atmosphere increases the surface energy of the silicone and thus provides a lower water contact angle. This phenomenon allows the epoxy adhesive to wet the silicone surface and ultimately bond. Bond strengths are sufficiently high to result in failures in the silicone materials rather than the adhesive bond.

  3. Adhesive wafer bonding using a molded thick benzocyclobutene layer for wafer-level integration of MEMS and LSI

    This paper describes a wafer bonding process using a 50 µm thick benzocyclobutene (BCB) layer which has vias and metal electrodes. The vias were fabricated by molding BCB using a glass mold. During the molding, worm-like voids grew between BCB and the mold due to the shrinkage of polymerizing BCB. They were completely removed by subsequent reflowing in N2. After patterning Al on the reflowed BCB for the electrodes and via connections, bonding with a glass substrate was performed. Voidless bonding without damage in the vias and electrodes was achieved. Through the process, the control of the polymerization degree of BCB is important, and thus the polymerization degree was evaluated by Fourier transform infrared spectroscopy. The developed process is useful for the wafer-bonding-based integration of different devices, e.g. micro electro mechanical systems and large-scale integrated circuits

  4. Bond strength of adhesive systems to human tooth enamel Resistência adesiva de sistemas adesivos ao esmalte dentário humano

    Thaís Cachuté Paradella

    2007-03-01

    Full Text Available The purpose of this study was to evaluate in vitro three adhesive systems: a total etching single-component system (G1 Prime & Bond 2.1, a self-etching primer (G2 Clearfil SE Bond, and a self-etching adhesive (G3 One Up Bond F, through shear bond strength to enamel of human teeth, evaluating the type of fracture through stereomicroscopy, following the ISO guidance on adhesive testing. Thirty sound premolars were bisected mesiodistally and the buccal and lingual surfaces were embedded in acrylic resin, polished up to 600-grit sandpapers, and randomly assigned to three experimental groups (n = 20. Composite resin cylinders were added to the tested surfaces. The specimens were kept in distilled water (37°C/24 h, thermocycled for 500 cycles (5°C-55°C and submitted to shear testing at a crosshead speed of 0.5 mm/min. The type of fracture was analyzed under stereomicroscopy and the data were submitted to Anova, Tukey and Chi-squared (5% statistical analyses. The mean adhesive strengths were G1: 18.13 ± 6.49 MPa, (55% of resin cohesive fractures; G2: 17.12 ± 5.80 MPa (90% of adhesive fractures; and G3: 10.47 ± 3.14 MPa (85% of adhesive fractures. In terms of bond strength, there were no significant differences between G1 and G2, and G3 was significantly different from the other groups. G1 presented a different type of fracture from that of G2 and G3. In conclusion, although the total etching and self-etching systems presented similar shear bond strength values, the types of fracture presented by them were different, which can have clinical implications.O objetivo deste estudo foi avaliar in vitro três sistemas adesivos: um monocomponente com condicionamento ácido total (G1 Prime & Bond 2.1, um "primer" autocondicionante (G2 Clearfil SE Bond e um adesivo autocondicionante (G3 One Up Bond F, através de resistência ao cisalhamento ao esmalte de dentes humanos, avaliando o tipo de fratura por estereomicroscopia, seguindo as normas ISO para testes

  5. Numerical Characterization of a Composite Bonded Wing-Box

    Smeltzer, Stanley S., III; Lovejoy, Andrew E.; Satyanarayana, Arunkumar

    2008-01-01

    The development of composite wing structures has focused on the use of mechanical fasteners to join heavily-loaded areas, while bonded joints have been used only for select locations. The focus of this paper is the examination of the adhesive layer in a generic bonded wing box that represents a "fastenerless" or unitized structure in order to characterize the general behavior and failure mechanisms. A global/local approach was applied to study the response of the adhesive layer using a global shell model and a local shell/solid model. The wing box was analyzed under load to represent a high-g up-bending condition such that the strains in the composite sandwich face sheets are comparable to an expected design allowable. The global/local analysis indicates that at these wing load levels the strains in the adhesive layer are well within the adhesive's elastic region, such that yielding would not be expected in the adhesive layer. The global/local methodology appears to be a promising approach to evaluate the structural integrity of the adhesively bonded structures.

  6. Tensile bond strength of adhesive systems: effects of primer and thermocycling Resistência à tração de sistemas adesivos: efeitos do “ primer” e dos ciclos térmicos

    Luciana Tibiriçá AGUILAR; de Rezende, Nathalie Pepe Medeiros; REIS, Alessandra; Alessandro Dourado LOGUERCIO; Grande, Rosa Helena Miranda; BALLESTER Rafael Yagüe; Julio da Motta SINGER

    2002-01-01

    The objective of this study was to evaluate the effects of primer and thermocycling on the bond strength of multi-purpose adhesive systems applied to enamel, under tensile stress. The following bonding systems were applied, according to the manufacturers' instructions, on unground enamel buccal surfaces of 96 premolars, with or without the application of primer: Scotchbond MP, OptiBond FL, Amalgambond Plus and OptiBond (dual-cure). A composite resin (Z100, 3M) was applied and light-cured in a...

  7. Surface characterization in composite and titanium bonding: Carbon fiber surface treatments for improved adhesion to thermoplastic polymers

    Devilbiss, T. A.; Wightman, J. P.

    1987-01-01

    The effect of anodization in NaOH, H2SO4, and amine salts on the surface chemistry of carbon fibers was examined by X-ray photoelectron spectroscopy (XPS). The surfaces of carbon fibers after anodization in NaOH and H2SO4 were examined by scanning transmission electron microscopy (STEM), angular dependent XPS, UV absorption spectroscopy of the anodization bath, secondary ion mass spectrometry, and polar/dispersive surface energy analysis. Hercules AS-4, Dexter Hysol XAS, and Union Carbide T-300 fibers were examined by STEM, angular dependent XPS, and breaking strength measurement before and after commercial surface treatment. Oxygen and nitrogen were added to the fiber surfaces by anodization in amine salts. Analysis of the plasmon peak in the carbon 1s signal indicated that H2SO4 anodization affected the morphological structure of the carbon fiber surface. The work of adhesion of carbon fibers to thermoplastic resins was calculated using the geometric mean relationship. A correlation was observed between the dispersive component of the work of adhesion and the interfacial adhesion.

  8. Comparison of the effect of shear bond strength with silane and other three chemical presurface treatments of a glass fiber-reinforced post on adhesion with a resin-based luting agent: An in vitro study

    Belwalkar, Vaibhavi Ramkrishna; Gade, Jaykumar; Mankar, Nikhil Purushottam

    2016-01-01

    Background: Loss of retention has been cited to be the most common cause of the failure of postretained restoration with irreversible consequences when materials with different compositions are in intimate contact at the post/adhesive interface. With this background, a study was conducted to improve the adhesion at the resin phase of fiber posts using silane and other chemical pretreatments. Materials and Methods: Hundred glass fiber-reinforced posts were tested with 4 different protocols (n = 25) using silane as a control (Group A) and other three experimental groups, namely, Group B-20% potassium permanganate, Group C-4% hydrofluoric acid, and Group D-10% hydrogen peroxide were pretreated on the postsurface followed by silanization. These specimens were bonded with dual-polymerizing resin-based luting agent, which were then loaded at the crosshead speed of 1 mm/min to record the shear bond strength at the post/adhesive interface. The data were analyzed using one-way ANOVA test for multiple group comparisons and the post hoc Bonferroni test for pairwise comparisons (P < 0.05). Results: Group B showed more influence on the shear bond strength when compared to other protocols, respectively (P < 0.001). Conclusion: Alone silanization as a surface treatment did not improve the bond strength. Combination of chemical presurface treatments followed by silanization significantly enhanced the bond strength at the post/adhesive interface. PMID:27307666

  9. Comparison of Non-Axisymmetric Dynamic Response of Imperfectly Bonded Buried Orthotropic Thick and Thin Fluid filled Cylindrical Shell due to Incident Shear Wave (SH Wave

    Rakesh Singh Rajput,

    2010-10-01

    Full Text Available This paper deals with the effect of fluid presence on the non-axisymmetric dynamic response of imperfectly bonded buried orthotropic thick and thin fluid filled pipeline due to incident horizontal shear wave. In the thin shell theory the effect of shear deformation and rotary inertia is not considered. The pipeline has been modeled as an infinite cylindrical shell imperfectly bonded to surrounding. An approach similar to Dwivedi and Upadhyay (1989 has been followed wherein a thin layer is assumed between the shell and the surrounding medium (soil such that this layer possesses the properties of stiffness and damping both. The degree of imperfection of the bond is varied by changing the stiffness and the damping parameters of this layer. Although a general formulation including P-, SV- and SHwave excitations has been presented, numerical results are given for the case of incident SH-waves only. When it is excited by seismic-wave there are two types of soil movements that take place at the time of earthquake both around the epicenter. One is vertical movement (up and down of the soil and due to this movement the shearwave (S-V and S-H is developed on the surface of the pipe and other is horizontal movement (compressive or extend of the soil due to this the longitudinal wave or pressure wave or P-wave is developed on the surface of the pipe. Since it is not possible to condense the results for P-, SV- and SH-waves into one paper, in this paper theresults concerning only the shear waves (SH Wave are to be presented..With increasing urban population and its dependence on utility services, dynamic response of pipelines to seismic excitation has become a subject of importance.

  10. Fracture analysis of adhesive joints in wind turbine blades

    Eder, Martin Alexander; Bitsche, Robert

    2015-01-01

    Modern wind turbine rotor blades are usually made from fibre-reinforced composite subcomponents. In the final assembly stage, these subcomponents are bonded together by several adhesive joints. One important adhesive joint is situated at the trailing edge, which refers to the downstream edge where...... the air-flow rejoins and leaves the blade. Maintenance inspections of wind turbine rotor blades show that among other forms of damage, local debonding of the shells along the trailing edge is a frequent failure type. The cause of trailing edge failure in wind turbine blades is complex, and detailed...... examination, the paper elucidates the influence of geometrical non-linearity in form of local buckling on both the increase of the energy release rate and the change of mode mixity. First, experimental results on adhesively bonded small-scale subcomponents are presented. Thereafter, a practical approach is...

  11. Marginal microleakage of cervical composite resin restorations bonded using etch-and-rinse and self-etch adhesives: two dimensional vs. three dimensional methods

    Khoroushi, Maryam

    2016-01-01

    Objectives This study was evaluated the marginal microleakage of two different adhesive systems before and after aging with two different dye penetration techniques. Materials and Methods Class V cavities were prepared on the buccal and lingual surfaces of 48 human molars. Clearfil SE Bond and Single Bond (self-etching and etch-and-rinse systems, respectively) were applied, each to half of the prepared cavities, which were restored with composite resin. Half of the specimens in each group underwent 10,000 cycles of thermocycling. Microleakage was evaluated using two dimensional (2D) and three dimensional (3D) dye penetration techniques separately for each half of each specimen. Data were analyzed with SPSS 11.5 (SPSS Inc.), using the Kruskal-Wallis and Mann-Whitney U tests (α = 0.05). Results The difference between the 2D and 3D microleakage evaluation techniques was significant at the occlusal margins of Single bond groups (p = 0.002). The differences between 2D and 3D microleakage evaluation techniques were significant at both the occlusal and cervical margins of Clearfil SE Bond groups (p = 0.017 and p = 0.002, respectively). The difference between the 2D and 3D techniques was significant at the occlusal margins of non-aged groups (p = 0.003). The difference between these two techniques was significant at the occlusal margins of the aged groups (p = 0.001). The Mann-Whitney test showed significant differences between the two techniques only at the occlusal margins in all specimens. Conclusions Under the limitations of the present study, it can be concluded that the 3D technique has the capacity to detect occlusal microleakage more precisely than the 2D technique. PMID:27200275

  12. Evaluation of Er,Cr:YSGG Laser Effect on Microshear Bond Strength of a Self-Adhesive Flowable Composite in the Dentin of Permanent Molar: An In Vitro Study

    Moslemi, Masoumeh; Javadi, Fatemeh; Khalili Sadrabad, Zahra; Shadkar, Zahra; Shadkar, Mohammad Saeid

    2016-01-01

    Aim and Background. Recently, new restorative materials such as self-adhesive flowable composites, because of their simple use and no need to bonding and etching, are considered important, particularly in pediatric dentistry. The aim of this study is to evaluate the effect of Er,Cr:YSGG laser on microshear bond strength of self-adhesive flowable composite on permanent teeth dentin in vitro. Material and Methods. In this experimental study, 40 dentin sections were prepared from healthy third molars and divided into two groups according to their surface preparation by Er,Cr:YSGG laser or without laser, only with silicon carbide paper. In each group, two groups of 10 teeth were treated with self-adhesive flowable composite (Dyad) and conventional flowable composite (acid etch and bonding). Samples were stored in normal saline and after 48 hours their bond strength was measured. The failure mode of samples was observed on stereomicroscope. In order to analyse the results, the one way ANOVA and Tukey's test for multiple comparisons were used. Result. The maximum bond strength was related to conventional flowable composite with laser preparation group (24/21 Mpa). The lowest one was seen in Dyad composite without laser emitting (9/89 Mpa). The statistical difference between this two groups was significant (P value = 0/0038). The microshear bond strength differences between Dyad composite groups with laser preparation (mean = 16/427 ± 1/79) and without laser preparation (mean = 12/85 ± 1/90) were statistically significant too (P value = 0/01). Conclusion. Self-adhesive flowable composite has lower microshear bond strength than conventional flowable composite. Moreover, the laser irradiation as a surface treatment can improve this bond strength. PMID:27493829

  13. Direct Covalent Grafting of Phytate to Titanium Surfaces through Ti-O-P Bonding Shows Bone Stimulating Surface Properties and Decreased Bacterial Adhesion.

    Córdoba, Alba; Hierro-Oliva, Margarita; Pacha-Olivenza, Miguel Ángel; Fernández-Calderón, María Coronada; Perelló, Joan; Isern, Bernat; González-Martín, María Luisa; Monjo, Marta; Ramis, Joana M

    2016-05-11

    Myo-inositol hexaphosphate, also called phytic acid or phytate (IP6), is a natural molecule abundant in vegetable seeds and legumes. Among other functions, IP6 inhibits bone resorption. It is adsorbed on the surface of hydroxyapatite, inhibiting its dissolution and decreasing the progressive loss of bone mass. We present here a method to directly functionalize Ti surfaces covalently with IP6, without using a cross-linker molecule, through the reaction of the phosphate groups of IP6 with the TiO2 layer of Ti substrates. The grafting reaction consisted of an immersion in an IP6 solution to allow the physisorption of the molecules onto the substrate, followed by a heating step to obtain its chemisorption, in an adaptation of the T-Bag method. The reaction was highly dependent on the IP6 solution pH, only achieving a covalent Ti-O-P bond at pH 0. We evaluated two acidic pretreatments of the Ti surface, to increase its hydroxylic content, HNO3 30% and HF 0.2%. The structure of the coated surfaces was characterized by X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, and ellipsometry. The stability of the IP6 coating after three months of storage and after sterilization with γ-irradiation was also determined. Then, we evaluated the biological effect of Ti-IP6 surfaces in vitro on MC3T3-E1 osteoblastic cells, showing an osteogenic effect. Finally, the effect of the surfaces on the adhesion and biofilm viability of oral microorganisms S. mutans and S. sanguinis was also studied, and we found that Ti-IP6 surfaces decreased the adhesion of S. sanguinis. A surface that actively improves osseointegration while decreasing the bacterial adhesion could be suitable for use in bone implants. PMID:27088315

  14. A 200 kHz Q-Switched Adhesive-Free Bond Composite Nd:YVO4 Laser using a Double-Crystal RTP Electro-optic Modulator

    YU Yong-Ji; CHEN Xin-Yu; WANG Chao; WU Chun-Ting; LIU Rui; JIN Guang-Yong

    2012-01-01

    A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported. A pair of RbTiOPOi (RTP) crystals are used as a high repetition EO Q-switch. At the repetition rate of 200kHz, the maximum average output power of 11.8 W at wavelength 1064 nm and full width at half maximum of pulses of 16.65 ns are achieved at an incident pump power of 27 W, corresponding to an optical conversion efficiency of 43.7% and a slope efficiency of 44.6%, respectively. To the best of our knowledge, this is the highest repetition rate reported on the EO Q-switched laser by using RTP crystals.%A diode-end-pumped electro-optic (EO) Q-switched adhesive-free bond composite Nd:YVO4 laser operating at a repetition rate of 200 kHz is reported.A pair of RbTiOPO4 (RTP) crystals are used as a high repetition EO Q-switch.At the repetition rate of 200kHz,the maximum average output power of 11.8 W at wavelength 1064 nm and full width at half maximum of pulses of 16.65ns are achieved at an incident pump power of 27 W,corresponding to an optical conversion efficiency of 43.7% and a slope efficiency of 44.6%,respectively.To the best of our knowledge,this is the highest repetition rate reported on the EO Q-switched laser by using RTP crystals.

  15. Micromorphology and bond strength evaluation of adhesive interface of a self-adhering flowable composite resin-dentin: Effect of surface treatment.

    Shafiei, Fereshteh; Saadat, Maryam

    2016-05-01

    This study evaluated the effect of dentin surface treatment on the micromorphology and shear bond strength (SBS) of a self-adhering flowable composite, Vertis Flow (VF). Flat dentin surfaces obtained from sixty extracted human molars were divided into six groups (n = 10) according to the following surface treatments: (G1) control, no treatment; (G2) self-etching adhesive, Optibond All-in-One; (G3) phosphoric acid etching for 15 s; (G4) polyacrylic acid for 10 s; (G5) EDTA for 60 s; and G6) sodium hypochlorite (NaOCl) for 15 s. After restoration using VF, SBS was measured in MPa. Data were analyzed using one-way ANOVA and Tamhane test (α = 0.05). Six additional specimens were prepared for scanning electron microscopy analysis. SBS was significantly affected by surface treatment (P < 0.001). SBS of six groups from the highest to the lowest were as follows: (G3) 13.5(A) ; (G5) 8.98(AB) ; (G2) 8.85(AB) ; (G4) 8.21(AB) ; (G1) 7.53(BC) ; and (G6) 4.49(C) (groups with the same superscript letter were statistically similar). Morphological analysis revealed numerous long resin tags at the adhesive interface for acid-etched group, with a few short resin tags for the control group and small gap formation for NaOCl-treated group. In conclusion, dentin surface treatments tested differently affected bonding performance of VF; only acid-etching effectively improved this. Microsc. Res. Tech. 79:403-407, 2016. © 2016 Wiley Periodicals, Inc. PMID:26918399

  16. Thermodynamic work of adhesion measurements of polymer bonded explosive constituents via the Wilhelmy plate technique and their application to AFM pull-off experiments

    A major strength limiting factor for polymer bonded explosives above their glass-transition conditions is the magnitude of adhesion that exists between the polymeric matrix binder-system and the filler particles. Experimental measurements of the components of the free surface energy of the binder KEL-F8OO have been made using the Wilhelmy Plate technique. These data can be combined with equivalent data on the filler particles to calculate the so-called Thermodynamic Work of Adhesion. This under-pinning quantity can be used to predict the levels of load (stress) required to cause debonding in different geometries. A simple geometry of interest is a spherical-cap of polymer debonding from a flat substrate. Experiments using this geometry have been performed with an Atomic Force Microscope pulloff technique to measure the critical loads (stresses) required for debonding. There is excellent agreement between the predicted values based on the Wilhelmy Plate data and the measured values from the Atomic Force Microscope. Experimental data and understanding are required for the development and validation of microstructural models of mechanical behaviour.

  17. Shape Bonding method

    Pontius, James T. (Inventor)

    2010-01-01

    The present invention is directed to a method of bonding at least two surfaces together. The methods step of the present invention include applying a strip of adhesive to a first surface along a predefined outer boundary of a bond area and thereby defining a remaining open area there within. A second surface, or gusset plate, is affixed onto the adhesive before the adhesive cures. The strip of adhesive is allowed to cure and then a second amount of adhesive is applied to cover the remaining open area and substantially fill a void between said first and second surfaces about said bond area. A stencil may be used to precisely apply the strip of adhesive. When the strip cures, it acts as a dam to prevent overflow of the subsequent application of adhesive to undesired areas. The method results in a precise bond area free of undesired shapes and of a preferred profile which eliminate the drawbacks of the prior art bonds.

  18. Resistência ao cisalhamento da colagem com compósitos utilizando potencializador de adesão Shear bond strength of composites using an adhesion booster

    Edivaldo de Morais

    2011-10-01

    Full Text Available OBJETIVO: avaliar a resistência ao cisalhamento dos compósitos Transbond XT e Concise Ortodôntico utilizando o potencializador de adesão Ortho Primer. MÉTODOS: a amostra consistiu de 90 incisivos bovinos divididos em seis grupos (n=15. Todos os dentes receberam profilaxia com pedra-pomes e condicionamento do esmalte com ácido fosfórico. No Grupo I, utilizou-se Transbond XT de maneira convencional. O Grupo II foi semelhante ao I, porém, aplicou-se o Ortho Primer ao invés do XT Primer. No Grupo III, após condicionamento, o esmalte foi contaminado com saliva, aplicou-se o Ortho Primer e colagem com Transbond XT. No Grupo IV, utilizou-se o Concise Ortodôntico de maneira convencional. O Grupo V foi semelhante ao IV, porém, utilizou-se o Ortho Primer ao invés da resina fluida. No Grupo VI, após condicionamento, o esmalte foi contaminado com saliva, aplicou-se o Ortho Primer e colagem com Concise. Os corpos de prova foram armazenados em água destilada em estufa a 37ºC por 24h e submetidos ao ensaio de resistência ao cisalhamento. Os dados foram submetidos à ANOVA e ao teste de Tukey (5%. RESULTADOS: a resistência da colagem no Grupo IV foi estatisticamente superior à dos Grupos II, III e VI (p0,05. O Transbond XT e o Concise utilizados convencionalmente obtiveram os maiores valores adesivos. O Ortho Primer em esmalte seco atuou efetivamente como agente de união dos compósitos avaliados. Em esmalte contaminado, a colagem com Concise obteve baixa resistência adesiva.OBJECTIVE: The aim of this study was to evaluate the shear bond strength of the Transbond XT and Concise Orthodontics composites using the Ortho Primer adhesion booster. METHODS: The sample consisted of 90 bovine incisors divided in 6 groups (n=15. All teeth were submitted to prophylaxes with pumice stone and etching with phosphoric acid. In Group I the Transbond XT was used conventionally. Group II was similar to Group I, however, Ortho Primer was used instead of XT

  19. Influence of artificial aging on the shear bond strength of zirconia-composite interfaces after pretreatment with new 10-MDP adhesive systems

    p.c pott

    2016-03-01

    Full Text Available Introduction: This in-vitro study investigates the bond strength of different zirconia composites  with three different modern adhesive systems after artificial aging using thermocycling and water storage. Methods: A total of 90 specimens of zirconia (InCoris, Sirona, Germany, Bernsheim were ground using a 165 µm grit rotating diamond disc. Thirty specimens were additionally treated with either Futurabond U “FBU” (VOCO GmbH, or Futurabond M+ “FBM” (VOCO GmbH or Futurabond M+ in combination with the DCA activator “FBMD” (VOCO GmbH. One of the three different types of composites – BifixSE “BS”, BifixQM “BQ” or GrandioSO “G” (VOCO GmbH – was bonded to the ten specimens of each group. All of the specimens underwent artificial aging using thermocycling between 5°C and 55°C for 5000 cycles followed by water storage for 100 days. Shear bond strength (SBS was determined in a universal testing machine. The type of failure was evaluated using fluorescence microscopy. The data were compared to existing data without artificial aging. Statistical analysis was performed with ANOVA and the Tukey test. Results: FBM and FBMD had higher SBS than FBU in combination with all tested composites, except BifixSE. In nearly all groups, artificial aging had no effect, with the exception of the combination of FBMD with BifixSE, in which there was a significant decrease in SBS after the aging process (p

  20. Study in electron microscopy the formation of the hybrid layer using adhesive systems One Coat and Single Bond Universal, at the Facultad de Medicina of the Universidad de Costa Rica

    The formation of the hybrid layer is observed in dental pieces in vitro, using systems of conventional adhesives (Single Bond 2 of 3M and One Coat of Coltene), with different times of acid etching, through the use of atomic force microscopy (AFM). The images of the hybrid layer obtained from samples prepared with adhesive systems are analyzed by AFM. Samples collected have been of dental pieces (molars and premolars) recently extracted and later placed in water. The pieces used have provided more surface to be observed under the microscope, greater accessibility to the be cut for its study, and to the great pieces have facilitated their placement on the Isomet low speed saw. The differences are evaluated between hybrid layers according the adhesive system used and the mode of application of the images obtained in the atomic force microscope. The adhesive system that has allowed the formation of a hybrid layer more appropriate between the adhesive system One Coat and the adhesive system Single Bond Universal is determined. The time of acid etching as variable of procedure is determined and has interfered with the formation of a hybrid layer more stable. The images evaluated that were provided by the atomic force microscope and compared with the images of electron microscopy of other studies, have determined that the AFM is without providing detailed information, as well as the appropriate images to evaluate the hybrid layer of the adhesive systems Single Bond 2 and One Coat of Coltene, or the different times of acid etching. Therefore, for this type of study, the image of choice must be of an electron microscope

  1. Eight-year randomized clinical evaluation of Class II nanohybrid resin composite restorations bonded with a one-step self-etch or a two-step etch-and-rinse adhesive

    van Dijken, Jan WV; Pallesen, Ulla

    2015-01-01

    -based nanohybrid resin composite (Ceram X) bonded with either a one-step self-etch adhesive (Xeno III) or a control two-step etch-and-rinse adhesive (Excite). The 165 restorations were evaluated using slightly modified United States Public Health Services (USPHS) criteria at baseline and then yearly during 8 years......Objectives: The aimof this study is to observe the durability of Class II nanohybrid resin composite restorations, placed with two different adhesive systems, in an 8-year follow-up. Methods: Seventy-eight participants received at random at least two Class II restorations of the ormocer....... Results: One hundred and fifty-eight restorations were evaluated after 8 years. Three participants with five restorations (three Xeno III, two Excite) were registered as dropouts. Twenty-one failed restorations (13.3 %) were observed during the follow-up. Twelve in the one-step self-etch adhesive group...

  2. OptiBond Solo粘接剂粘接银汞合金剪切力测试%Measuremnt of shear bond strength between single component adhesive OptiBond Solo and amalgam

    宋萍; 詹福良

    2001-01-01

    目的检验单组份粘接剂OptiBond Solo粘接银汞合金的剪切强度.方法利用电子拉伸试验机对OptiBond Solo粘接银汞合金的剪切力进行测试,并与常规银汞充填进行了比较.结果试验组剪切力为21.77±7.26MPa,对照组剪切力为12.86±2.54 MPa,两者差异有显著性意义(P<0.01).结论 OptiBond Solo粘接剂操作简便,粘接强度高,值得在临床上推广.

  3. Bond formation and slow heterogeneous dynamics in adhesive spheres with long-ranged repulsion: quantitative test of mode coupling theory.

    Henrich, O; Puertas, A M; Sperl, M; Baschnagel, J; Fuchs, M

    2007-09-01

    A colloidal system of spheres interacting with both a deep and narrow attractive potential and a shallow long-ranged barrier exhibits a prepeak in the static structure factor. This peak can be related to an additional mesoscopic length scale of clusters and/or voids in the system. Simulation studies of this system have revealed that it vitrifies upon increasing the attraction into a gel-like solid at intermediate densities. The dynamics at the mesoscopic length scale corresponding to the prepeak represents the slowest mode in the system. Using mode coupling theory with all input directly taken from simulations, we reveal the mechanism for glassy arrest in the system at 40% packing fraction. The effects of the low-q peak and of polydispersity are considered in detail. We demonstrate that the local formation of physical bonds is the process whose slowing down causes arrest. It remains largely unaffected by the large-scale heterogeneities, and sets the clock for the slow cluster mode. Results from mode-coupling theory without adjustable parameters agree semiquantitatively with the local density correlators but overestimate the lifetime of the mesoscopic structure (voids). PMID:17930244

  4. Tensile bond srength between composite resin using different adhesive systems Avaliação da resistência à ruptura por tração entre resina composta e diversos adesivos dentinários

    Patrícia Dias

    2002-11-01

    Full Text Available The aim of this study was evaluate the tensile bond strength (TBS among nine adhesive systems and one composite resin. The groups were made as follows: Single Bond/3M (G1, Etch & Prime 3.0 /Degussa (G2, Bond 1/Jeneric/Pentron (G3, Prime & Bond 2.1/Dentsply (G4, OptiBond FL/Kerr (G5, Stae/SDI (G6, Snap Bond/ Copalite-Cooley & Cooley (G7, Prime & Bond NT/Dentsply (G8, Scotchbond Multi Purpose Plus/3M (G9. The control group (G10 was made only with the composite resin (Z100/3M. One hundred specimens were made, 10 for each group. There were significant differences on TBS among groups. G3 showed the hightest TBS in comparison to other tested groups. G10 presented higher TBS than all groups. O objetivo desta pesquisa foi investigar in vitro a resistência de união entre uma resina composta e nove sistemas adesivos dentinários. Os adesivos estudados foram assim agrupados: Single Bond/3M (G1, Etch & Prime 3.0/ Degussa (G2, Bond 1/Jeneric/Pentron (G3, Prime & Bond 2.1/Dentsply (G4, OptiBond FL/Kerr (G5, Stae/SDI (G6, Snap Bond/Copalite (G7, Prime & Bond NT/Dentsply (G 8, Scotchbond Multi Purpose Plus/3M (G9. O Grupo controle (G10. foi confeccionado somente com a resina composta (Z100/3M. Foram confeccionados 100 espécimes, 10 para cada grupo. Houve diferenças estatísticas significantes entre os grupos. O grupo 3 foi o que mostrou a mais alta resistência em comparação aos nove testados. O grupo controle (G10 apresentou a mais alta resistência entre todos os Grupos.  

  5. Adhesive bonding of resin composite to various titanium surfaces using different metal conditioners and a surface modification system

    Hercules Jorge ALMILHATTI

    2013-12-01

    Full Text Available Objective: This study evaluated the effect of three metal conditioners on the shear bond strength (SBS of a prosthetic composite material to cpTi grade I having three surface treatments. Material and Methods: One hundred sixty eight rivet-shaped specimens (8.0x2.0 mm were cast and subjected to polishing (P or sandblasting with either 50 mm (50SB or 250 mm (250SB Al2O3. The metal conditioners Metal Photo Primer (MPP, Cesead II Opaque Primer (OP, Targis Link (TL, and one surface modification system Siloc (S, were applied to the specimen surfaces, which were covered with four 1-mm thick layers of resin composite. The resin layers were exposed to curing light for 90 s separately. Seven specimens from each experimental group were stored in water at 37ºC for 24 h while the other 7 specimens were subjected to 5,000 thermal cycles consisting of water baths at 4ºC and 60ºC (n=7. All specimens were subjected to SBS test (0.5 mm/min until failure occurred, and further 28 specimens were analyzed using scanning electron microscope (SEM and X-ray energy-dispersive spectroscopy (EDS. Data were analyzed by 3-way ANOVA followed by post-hoc Tukey's test (α=0.05. Results: On 50SB surfaces, OP groups showed higher SBS means than MPP (P<0.05, while no significant difference was found among OP, S, and TL groups. On 250SB surfaces, OP and TL groups exhibited higher SBS than MPP and S (P<0.05. No significant difference in SBS was found between OP and TL groups nor between MPP and S groups. The use of conditioners on 250SB surfaces resulted in higher SBS means than the use of the same products on 50SB surfaces (P<0.05. Conclusion: Sandblasting associated with the use of metal conditioners improves SBS of resin composites to cpTi.

  6. 橡胶履带芯金粘合工艺及其脱胶分析%Bonding Process of Metal Core in Rubber Track and Analysis on Adhesion Failure

    王丽莉; 王克成

    2015-01-01

    介绍橡胶履带芯金粘合工艺及其脱胶分析。粘合工艺:芯金先进行外观、尺寸、抗弯强度和硬度等检测,再进行喷砂、脱脂和磷化等表面处理,芯金底涂胶粘剂和面涂胶粘剂的涂覆方式有手工涂刷、手工浸涂、自动浸涂、手工喷涂和自动喷涂。通过硫化,橡胶履带芯金与橡胶粘合成整体。选择适合的胶粘剂品种、橡胶配方、芯金喷砂工艺、胶粘剂涂覆工艺和硫化工艺是解决橡胶履带芯金脱胶的有效措施。%This paper introduces the bonding process of the metal core in rubber track and the adhesion failure was analyzed. In the ifrst step of the bonding process, the metal core was inspected, including visual inspection, dimension, bending strength and hardness. Then the metal core was treated by sandblasting, degreasing and phosphating. In the second step, the primer and adhesive were applied. The process could be brushing, manual dipping, automatic dipping, manual spraying or automatic spraying. Then rubber track was bonded to metal core and the rubber track was vulcanized. To effectively minimize the adhesion failure, it was recommended to use suitable adhesive, rubber compound formulation, sandblasting process, adhesive application process and vulcanization process.

  7. Preparation and Properties of Starch-Based Composite Adhesive for Wood Bonding%木材用淀粉基复合胶黏剂的制备与性能

    王必囤; 顾继友; 左迎峰; 张彦华

    2012-01-01

    Starch adhesive was synthesized with com starch oxidized by sodium hypochlorite sodium, and then starch-isocyanate composite adhesive was prepared by blending modification with functional inner-crosslinking agent ( isocyanate). The effects of pH, polyvinyl alcohol (PVA) concentration, PVA dosage, starch content, and mixing ratio of isocyanate on the bonding properties of the starch adhesive were studied under different experimental conditions. The best bonding strength and water resistance were obtained as PVA concentration 10% , ratio of starch to PVA 3:5, ratio of starch to water 3 '· 8, and using oxidized modified starch. XPS analysis shows that chemical bond formation between isocyanate and hydroxyl of starch adhesive and wood is key to improving bonding strength and water resistance. The modified starch adhesive exhibits better adhesive properties, which meet the application requirements for type II plywood.%采用次氯酸钠对玉米淀粉进行氧化制备淀粉胶黏剂,再用功能内交联剂(异氰酸酯)共混改性制备淀粉基复合胶黏剂.考查了复合胶黏剂体系的pH、PVA质量分数与用量、淀粉用量、异氰酸酯加入比例对淀粉基复合胶黏剂胶接性能的影响.胶接实验结果表明:利用变性的氧化淀粉,PVA质量分数为10%,PVA加入比例为3/5,淀粉与水比为3/8时,获得最佳的胶结强度和耐水性能.采用XPS分析胶层化学结构,结果表明:异氰酸酯与淀粉胶黏剂、木材中的羟基反应形成化学键结合是提高胶接强度和耐水性关键所在.所制得的改性淀粉胶黏剂性能更加优异,符合Ⅱ类胶合板的使用要求.

  8. Radiation-curable adhesives

    Radiation-curable adhesives may be classified into two broad categories. In the first category, adhesive bonding occurs as a direct result of irradiation. The second category includes pressure-sensitive and hot-melt adhesives, which are composed of linear or lightly cross-linked polymers prepared by a radiation-induced polymerization reaction. This chapter is mainly concerned with radiation-curable adhesives of the first category. The various adhesive types are discussed and adhesive performance is examined, particularly in relation to the chemistry and chemical technology which underlies the individual materials. A description of a limited number of representative applications is included as is an outline of recent developments of curing and dispensing equipment. 268 refs., 14 figs., 13 tabs

  9. The Mechanical Properties of Castor Seed Shell-polyester Matrix Composites

    S.C. Nwigbo

    2013-05-01

    Full Text Available A composite with a polyester matrix reinforced with chemically modified shells of castor seed (Ricinus communis was produced. The effect of the shell (filler on the mechanical properties of the composite was experimentally quantified. A preliminary study was earlier carried out the shell in terms of their chemical constituents, functional group and mechanical strength. The shell was ground and chemically treated to enhance good bonding and adhesion to the matrix. Composites were fabricated using a hand lay-up or contact mould method for different percentage compositions of the filler. Tests, with respect to the mechanical properties (i.e., tensile, flexural and creep response were carried out. The result obtained was compared with the unreinforced polyester plate. It was observed that the inclusion of the filler (shell added strength to the composite. Scanning Electron Microscopy (SEM was taken on the composite samples to study the morphology of the composites.

  10. 两种粘接剂对四环素牙本质粘接性能的比较研究%The adhesive properties of two bonding systems to tetracycline stained dentin

    刘虹伶; 梁坤能; 程磊; 李继遥; 何利邦

    2016-01-01

    目的 比较两种粘接剂对四环素牙本质与正常牙本质的粘接性能,为临床四环素牙本质粘接剂的选择提供参考.方法 从四川大学华西口腔医学院口腔颌面外科门诊收集牙冠完整的离体四环素牙及正常牙各10颗,制备(牙合)面牙本质平面试件,分为四环素牙本质全酸蚀粘接剂组(Single Bond 2,实验1组)和自酸蚀粘接剂组(SE Bond,实验2组),正常牙本质Single Bond 2组(对照1组)和正常牙本质SE Bond组(对照2组),每组分别为5颗牙,35个试件.通过测试比较4组牙本质试件的粘接强度及树脂转化率.结果 实验1组的微拉伸强度[(16.17±3.16) MPa]及树脂转化率[(55±6)%]均显著低于实验2组[微拉伸强度:(25.82±2.62) MPa,树脂转化率:(66±3)%](P<0.05),也显著低于两个对照组[微拉伸强度及树脂转化率分别为对照1组:(29.13±2.44) MPa、(64±5)%;对照2组:(24.29±2.83) MPa、(65±4)%],差异均有统计学意义(P<0.05).结论 自酸蚀粘接系统对四环素牙本质的粘接效果强于全酸蚀粘接系统.%Objective To investigate and compare the bonding properties of Single Bond 2 and SE Bond to tetracycline stained dentin in vitro.Methods Ten extracted tetracycline stained human teeth and ten extracted normal human teeth were collected and the occlusal dentin surfaces of all extracted teeth were exposed.The tetracycline stained teeth and normal teeth were divided into two groups, respectively and randomly, based on the adhesives applied.Total-etch adhesive(Single Bond 2) and self-etch adhesive(SE Bond) were used.After application of the adhesives to the dentin surfaces, composite crowns were built up.After 24 h water storage, the teeth were sectioned longitudinally into sticks(0.9 mm×0.9 mm bonding area) for micro tensile testing or micro Raman spectroscopy detection.Bonding strength(μTBS) and resin conversion rate were analyzed using one-way ANOVA.Results The tetracycline Single Bond 2 group

  11. Electronic Structure and Bonding of Icosahedral Core-Shell Gold-Silver Nanoalloy Clusters Au_(144-x)Ag_x(SR)_60

    Malola, Sami

    2011-01-01

    Atomically precise thiolate-stabilized gold nanoclusters are currently of interest for many cross-disciplinary applications in chemistry, physics and molecular biology. Very recently, synthesis and electronic properties of "nanoalloy" clusters Au_(144-x)Ag_x(SR)_60 were reported. Here, density functional theory is used for electronic structure and bonding in Au_(144-x)Ag_x(SR)_60 based on a structural model of the icosahedral Au_144(SR)_60 that features a 114-atom metal core with 60 symmetry-equivalent surface sites, and a protecting layer of 30 RSAuSR units. In the optimal configuration the 60 surface sites of the core are occupied by silver in Au_84Ag_60(SR)_60. Silver enhances the electron shell structure around the Fermi level in the metal core, which predicts a structured absorption spectrum around the onset (about 0.8 eV) of electronic metal-to-metal transitions. The calculations also imply element-dependent absorption edges for Au(5d) \\rightarrow Au(6sp) and Ag(4d) \\rightarrow Ag(5sp) interband transit...

  12. Abdominal Adhesions

    ... adhesions? Abdominal adhesions can cause intestinal obstruction and female infertility—the inability to become pregnant after a year of trying. Abdominal adhesions can lead to female infertility by preventing fertilized eggs from reaching the uterus, ...

  13. Adhesive-Bonded Ca(Mg_(1/3)Nb_(2/3))O_3/Ba(Zn_(1/3)Nb_(2/3))O_3 Layered Dielectric Resonators

    2005-01-01

    Ca(Mg_ 1/3 Nb_ 2/3 )O_3 and Ba(Zn_ 1/3 Nb_ 2/3 )O_3 ceramic cylinders with the same diameter were bonded by adhesive with low dielectric loss to yield the layered dielectric resonators, and the microwave dielectric characteristics were evaluated with TE_ 01δ mode. With increasing the Ba(Zn_ 1/3 Nb_ 2/3 )O_3 thickness fraction, the resonant frequency (f_0) decreased, while the effective dielectric constant (ε_ r,eff ) and temperature coefficient of resonant frequency (τ_f) increased. Good microwave dielectri...

  14. Tensile bond strength of adhesive systems: effects of primer and thermocycling Resistência à tração de sistemas adesivos: efeitos do “ primer” e dos ciclos térmicos

    Luciana Tibiriçá AGUILAR

    2002-03-01

    Full Text Available The objective of this study was to evaluate the effects of primer and thermocycling on the bond strength of multi-purpose adhesive systems applied to enamel, under tensile stress. The following bonding systems were applied, according to the manufacturers' instructions, on unground enamel buccal surfaces of 96 premolars, with or without the application of primer: Scotchbond MP, OptiBond FL, Amalgambond Plus and OptiBond (dual-cure. A composite resin (Z100, 3M was applied and light-cured in a cast metal hollow cone, which was previously fixed to the enamel surfaces. Half of the sample was subjected to 3,000 thermocycles (5-37ºC; 37-55ºC, dwell time of 60 s, and the other half was stored in water at 37ºC for the same period. The data were treated by means of ANOVA and no significant effects were detected, which indicates that tensile bond strength was not affected by the adhesive systems, application of primer or thermocycling.O objetivo desta pesquisa foi o de verificar o efeito do "primer" e dos ciclos térmicos na resistência da união entre adesivos multiuso e esmalte dental, sob ensaios de tração. Os seguintes sistemas adesivos foram aplicados, de acordo com as instruções dos fabricantes, na superfície vestibular (sem desgaste de 96 pré-molares com ou sem a aplicação prévia do "primer": Scotchbond MP, OptiBond FL, Amalgambond Plus e OptiBond - "dual cure". Após a aplicação do sistema adesivo, foi confeccionado um cone de resina composta (Z100, 3M, e fotoativado dentro de um molde metálico. Metade do total de espécimes foi submetida a 3.000 ciclos térmicos (5-37ºC; 37-55ºC, 60 s de imersão; a outra metade permaneceu imersa em água a 37ºC pelo mesmo tempo dispensado no procedimento anterior. Os dados foram submetidos a uma análise de variância (p = 0,05 e nenhum efeito significante foi detectado, indicando que a resistência de união não foi afetada pelo sistema adesivo, pela aplicação do "primer" ou pelos ciclos térmicos.

  15. Reactive Bonding Film for Bonding Carbon Foam Through Metal Extrusion

    Chertok, Maxwell; Irving, Michael; Neher, Christian; Tripathi, Mani; Wang, Ruby; Zheng, Gayle

    2016-01-01

    Future tracking detectors, such as those under development for the High Luminosity LHC, will require mechanical structures employing novel materials to reduce mass while providing excellent strength, thermal conductivity, and radiation tolerance. Adhesion methods for such materials are under study at present. This paper demonstrates the use of reactive bonding film as an adhesion method for bonding carbon foam.

  16. Characterization of fatigue damage in adhesively bonded lap joints through dynamic, full-spectral interrogation of fiber Bragg grating sensors: 2. Simulations

    In this paper, we simulate the response of fiber Bragg grating (FBG) sensors embedded in the adhesive layer of a composite lap that is subjected to harmonic excitation. To simulate accumulated fatigue damage at the adhesive layer, two forms of numerical nonlinearities are introduced into the model: (1) progressive plastic deformation of the adhesive and (2) changing the boundary of an interfacial defect at the adhesive layer across the overlap shear area. The simulation results are compared with previous measurements of the dynamic, full-spectral response of such FBG sensors for condition monitoring of the lap joint. Short-time Fourier transforms (STFT) of the locally extracted axial strain time histories reveal a transition to nonlinear behavior of the composite lap joint by means of intermittent frequencies that were observed in the experimental measurements and are not associated with the external excitation. The simulation results verify that the nonlinear changes in measured dynamic FBG responses are due to the progression of damage in the lap joint. (paper)

  17. 五种牙本质粘接剂对乳牙牙本质粘接性能的比较%Comparison of bonding properties of five adhesives in primary dentin

    崔悦; 张祖太; 葛丽华; 丁宁; 杨东梅

    2013-01-01

    Objective To evaluate the microtensile bond strength (μTBS) of five dentin adhesives and their respective fracture modes.Methods The flat dentine surfaces of 75 primary teeth were randomly divided into five groups,which was treated with FL-Bond Ⅱ (group A),Clearfil Protect Bond (group B),Clearfil SE Bond(group C),AdperTM Easy One(group D),and Single Bond 2(group E) respectively.The μTBS was determined with microtensile tester and the fracture mode was observed by scanning electron microscope (SEM).Results The mean μTBS for group A,B,C,D and E was (28.3 ± 2.2),(32.4 ± 2.5),(38.3 ± 2.8),(32.9 ± 3.4) and (23.2 ± 1.9) MPa respectively.There was significant difference between group C and group A,E (P < 0.01),and no significant difference between group C and group B,D.There was no significant difference between group A and group E (P > 0.05).The SEM indicated that there was no significant difference in the fracture mode.Conclusions The bonding property of Clearfil Protect Bond is equivalent to Clearfil SE Bond and AdperTM Easy One,superior to Single Bond 2 and more suitable for primary dentin bonding.%目的 检测5种牙本质粘接剂对乳牙牙本质的粘接性能,为牙本质粘接剂的临床使用提供依据.方法 按随机数表法将75颗因滞留拔除的乳磨牙分为5组,每组15颗.各标本磨除表面牙釉质,暴露的牙本质面分别根据不同粘接系统的说明进行酸蚀粘接,树脂充填.使用A(FL-Bond Ⅱ)、B(Clearfil Protect Bond)、C(Clearfil SE Bond)、D(AdperTM Easy One)、E(Single Bond 2)粘接系统进行粘接(分别为A、B、C、D、E组),用微拉伸测试仪检测微拉伸强度.扫描电镜观察样本的断裂类型.结果 各组的微拉伸强度分别为A组:(28.3±2.2)MPa,B组:(32.4±2.5)MPa,C组:(38.3±2.8) MPa,D组:(32.9±3.4)MPa,E组:(23.2±1.9) MPa,C组与A、E组差异有统计学意义(P<0.01),C组与B组、D组差异无统计学意义(P>0.05),A组与E组差异无统计学意义(P>0.05).扫描

  18. Nonwoven glass fiber mat reinforces polyurethane adhesive

    Roseland, L. M.

    1967-01-01

    Nonwoven glass fiber mat reinforces the adhesive properties of a polyurethane adhesive that fastens hardware to exterior surfaces of aluminum tanks. The mat is embedded in the uncured adhesive. It ensures good control of the bond line and increases the peel strength.

  19. The research on the bond durability between self-adhesive cements and zirconia ceramic%自粘接树脂水门汀与二氧化锆陶瓷间粘接耐久性的研究

    景页; 孟翔峰

    2013-01-01

      目的比较不同自粘接树脂水门汀与二氧化锆陶瓷间的粘接强度和耐久能力。方法二氧化锆陶瓷片经烧结、研磨后,接受50μm Al2O3颗粒喷砂处理。使用激光共聚焦显微镜对研磨、喷砂处理的陶瓷表面粗糙度进行测量。研磨、喷砂处理的陶瓷片分别与5种自粘接树脂水门汀: Biscem(BC)、 G-Cem(GC)、 RelyX U100(RU)、Multilink Speed(MS)、 Maxcem(MC)进行粘接。每组粘接试件分为2个亚组分别接受0、10000次冷热循环后进行剪切粘接强度测量。使用单因素方差和独立样本t检验对数据进行分析。结果喷砂处理明显增加了陶瓷表面粗糙度指标Ra值(P<0.001)。冷热循环降低了所有实验组的粘接强度(P<0.001),其中研磨处理陶瓷片与MS组的粘接强度明显高于与BC组、 GC组、 RU组和MC组(P<0.001),喷砂处理明显提高了BC组、 GC组、 RU组和MC组的粘接强度(P<0.001)。结论不同自粘接树脂水门汀与二氧化锆陶瓷间的粘接耐久能力存在明显差异,其粘接耐久能力不完全受陶瓷表面喷砂处理的影响。%Objective To compare the bond durability of five self-adhesive resin cements to polished and sand-blasted zirconia ceramic. Methods Zirconia ceramic samples were sintered and polished. Half of polished ceramic samples were sandblasted with 50μm alumina particles. The roughness of polished and sandblasted zirconia ceramic surface was measured by 3D-laser scanning microscope. The polished and sandblasted ceramic samples were bonded to composite cylinders with either Biscem(BC), G-Cem(GC), RelyX U100(RU), Multilink Speed(MS) or Maxcem (MC). The samples divided into two subgroups to receive respectively shear test after 0 and 10 000 time thermal cy-cles. The data were analyzed by one-way ANOVA test and independent sample t test. Results Air abrasion signifi-cantly increased Ra of zirconia ceramic surface(P<0

  20. The grafting and release behavior of doxorubincin from Fe{sub 3}O{sub 4}-SiO{sub 2} core-shell structure nanoparticles via an acid cleaving amide bond: the potential for magnetic targeting drug delivery

    Chen, F H; Gao, Q; Ni, J Z [State Key Laboratory of Rare Earth Resources and Application, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)], E-mail: jzni@ciac.jl.cn

    2008-04-23

    Fe{sub 3}O{sub 4}-SiO{sub 2} core-shell structure nanoparticles were first prepared and characterized by TEM, FTIR, XPS and XRD. Subsequently the widely used anticancer agent doxorubincin (DOX) was successfully grafted to the surface of the core-shell nanoparticles via an amide bond with the aid of a spacer arm we synthesized. The spacer arm met two needs: one end can couple to the core-shell nanoparticles' surface while the other end was the active -COOH group, which can react with the -NH{sub 2} group of DOX molecules. The synthesized spacer arm and the conjugation of the drug with nanoparticles through amidation were confirmed by FTIR. The DOX-loading efficiency determined by UV-vis spectrometer was 86.5%. Drug release experiments displayed a pH-dependent behavior that DOX was cleaved from the nanoparticles easily under low pH conditions in the presence of protease and that most of the conjugated doxorubincin were released within the first 12 h. The prepared DOX-grafted Fe{sub 3}O{sub 4}-SiO{sub 2} core-shell structure nanoparticles showed a superparamagnetic property with a saturation magnetization value of 49.3 emu g{sup -1}, indicating a great potential application in the treatment of cancer using magnetic targeting drug-delivery technology.

  1. Evaluación de la adherencia de uniones adhesivas metálicas con adhesivos epoxídicos modificados Evaluation of the adherence of bonded metallic joints with modified epoxy adhesives

    Filiberto González Garcia

    2008-03-01

    agents. The adhesive properties were investigated using the epoxy resins as independent systems as well as the modified resin. The adhesive properties of modified and unmodified epoxy resins were studied using steel alloy (ASTM A36 as adherent. The adherence has been evaluated using three geometric assays of steel-steel bonded joints. The rheological behavior of the adhesives was investigated under isothermal conditions. The rheological parameters associated with the curing reaction such as reaction rate, pot life and gel time of the pure adhesives were related to the chemical structure of the curing agents. The cloud point and the gel time of the modified adhesives were related to the morphology and the reaction rate, respectively. The morphology was characterized by scanning electronic microscopy. The adherence of the adhesive joints at different mechanical solicitations was related to the generated morphology by the dispersed phase of each modifier and the networks structures of the epoxy adhesives.

  2. Solvent-free thermoplastic-poly(dimethylsiloxane) bonding mediated by UV irradiation followed by gas-phase chemical deposition of an adhesion linker

    Ahn, S. Y.; Lee, N. Y.

    2015-07-01

    Here, we introduce a solvent-free strategy for bonding various thermoplastic substrates with poly(dimethylsiloxane) (PDMS) using ultraviolet (UV) irradiation followed by the gas-phase chemical deposition of aminosilane on the UV-irradiated thermoplastic substrates. The thermoplastic substrates were first irradiated with UV for surface hydrophilic treatment and were then grafted with vacuum-evaporated aminosilane, where the alkoxysilane side reacted with the oxidized surface of the thermoplastic substrate. Next, the amine-terminated thermoplastic substrates were treated with corona discharge to oxidize the surface and were bonded with PDMS, which was also oxidized via corona discharge. The two substrates were then hermetically sealed and pressed under atmospheric pressure for 30 min at 60 °C. This process enabled the formation of a robust siloxane bond (Si-O-Si) between the thermoplastic substrate and PDMS under relatively mild conditions using an inexpensive and commercially available UV lamp and Tesla coil. Various thermoplastic substrates were examined for bonding with PDMS, including poly(methylmethacrylate) (PMMA), polycarbonate (PC), poly(ethyleneterephthalate) (PET) and polystyrene (PS). Surface characterizations were performed by measuring the contact angle and performing x-ray photoelectron spectroscopy analysis, and the bond strength was analyzed by conducting various mechanical force measurements such as pull, delamination, leak and burst tests. The average bond strengths for the PMMA-PDMS, PC-PDMS, PET-PDMS and PS-PDMS assemblies were measured at 823.6, 379.3, 291.2 and 229.0 kPa, respectively, confirming the highly reliable performance of the introduced bonding strategy.

  3. Atmospheric pressure plasma jet deposition of Si-based coupling films as surface preparation for structural adhesive bonding in the aircraft industry

    Bringmann, Philipp

    2016-01-01

    Damages of metallic aircraft structures that occur during manufacturing, assembly and in service require local repair. Especially with current service-life extensions of ageing aircraft fleets, the importance of such repair methods is increasing. Typically, the repair of smaller damages on aluminium fuselage or wing skins is done by riveting a patch onto the flawed structure. However, the use of rivets reduces the strength of the structure and promotes fatigue. Joining the patch by adhesive b...

  4. Shell Venster

    In the bi-monthly issues of 'Shell Venster' (window on Shell) attention is paid to the activities of the multinational petroleum company Shell Nederland and the Koninklijke/Shell Groep by means of non-specialist articles

  5. Weak bond screening system

    Chuang, S. Y.; Chang, F. H.; Bell, J. R.

    Consideration is given to the development of a weak bond screening system which is based on the utilization of a high power ultrasonic (HPU) technique. The instrumentation of the prototype bond strength screening system is described, and the adhesively bonded specimens used in the system developmental effort are detailed. Test results obtained from these specimens are presented in terms of bond strength and level of high power ultrasound irradiation. The following observations were made: (1) for Al/Al specimens, 2.6 sec of HPU irradiation will screen weak bond conditions due to improper preparation of bonding surfaces; (2) for composite/composite specimens, 2.0 sec of HPU irradiation will disrupt weak bonds due to under-cured conditions; (3) for Al honeycomb core with composite skin structure, 3.5 sec of HPU irradiation will disrupt weak bonds due to bad adhesive or oils contamination of bonding surfaces; and (4) for Nomex honeycomb with Al skin structure, 1.3 sec of HPU irradiation will disrupt weak bonds due to bad adhesive.

  6. Bonding ability of adhesive resins to caries-affected and caries-infected dentin Capacidade de união de resinas adesivas à dentina afetada e infectada por cárie

    Masahiro Yoshiyama

    2004-09-01

    Full Text Available Hybridized dentin permits dental treatments that were previously impossible with conventional techniques, opening new frontiers in modern adhesive dentistry. We have investigated the adhesive property of current bonding systems to caries-infected dentin by a microtensile bond strength test (µTBS and transmission electron microscopy (TEM, and suggested that bonding resin could infiltrate into caries-infected dentin partially to embed carious bacteria within hybrid layers. We have named this concept of caries control as modified sealed restoration (MSR. On the other hand, Kuraray Medical Inc. (Tokyo, Japan has developed an antibacterial adhesive system (ABF, now marketed in USA as Protect Bond. So as to evaluate the effectiveness of ABF on root caries control, we have examine the microtensile bond strengths (µTBS of ABF to normal versus carious root dentin and the interfacial morphology by a scanning electron microscopy (SEM. ABF could form the hybrid-like structures by infiltrating into the surfaces of the root carious dentin, and the mean value of µTBS of ABF to root carious dentin was 23.0 MPa. These results suggested that MSR combined with ABF might be an advantageous minimal invasive therapy for root caries.As técnicas adesivas permitiram inovações nos tratamentos restauradores da atualidade. Este estudo investigou a qualidade de união de diferentes sistemas adesivos ao substrato dentinário afetado e infectado por cárie, através de testes de microtração e microscopia eletrônica de transmissão e varredura (MET. Os resultados sugerem que a resina adesiva pôde infiltrar na dentina infectada e envolver as bactérias na camada híbrida. Esse conceito de controle da cárie foi denominado de "Restauração-Selante Modificada" (RSM. Por outro lado, a empresa Kuraray Med. Inc .(Japão desenvolveu um sistema adesivo com propriedades anti-bacterianas (ABF, o qual é comercializado nos EUA como Protect Bond. Para avaliar a efetividade do

  7. Adhesive Categories

    Lack, Stephen; Sobocinski, Pawel

    2003-01-01

    We introduce adhesive categories, which are categories with structure ensuring that pushouts along monomorphisms are well-behaved. Many types of graphical structures used in computer science are shown to be examples of adhesive categories. Double-pushout graph rewriting generalises well to...... rewriting on arbitrary adhesive categories....

  8. Adhesive Categories

    Lack, Stephen; Sobocinski, Pawel

    2004-01-01

    We introduce adhesive categories, which are categories with structure ensuring that pushouts along monomorphisms are well-behaved. Many types of graphical structures used in computer science are shown to be examples of adhesive categories. Double-pushout graph rewriting generalises well to...... rewriting on arbitrary adhesive categories....

  9. Testing Bond Strength, a Review of the Literature

    de Munck, Jan; Mine, Atsushi; Poitevin, André; Van Ende, Annelies; Meerbeek, Bart Van

    2009-01-01

    Objectives: Worldwide bond strength tests are used to evaluate bonding effectiveness of different adhesive techniques. The purpose of this study was to systematically collect these data to identify the primary parameters that affect the outcome of bond strength tests, and to attempt to disclose trends in adhesive performance of the different adhesive approaches today available. Materials and Methods: 871 studies were identified by enterin...

  10. Ceramic microstructure and adhesion

    Buckley, D. H.

    1985-01-01

    When a ceramic is brought into contact with a ceramic, a polymer, or a metal, strong bond forces can develop between the materials. The bonding forces will depend upon the state of the surfaces, cleanliness and the fundamental properties of the two solids, both surface and bulk. Adhesion between a ceramic and another solid are discussed from a theoretical consideration of the nature of the surfaces and experimentally by relating bond forces to interface resulting from solid state contact. Surface properties of ceramics correlated with adhesion include, orientation, reconstruction and diffusion as well as the chemistry of the surface specie. Where a ceramic is in contact with a metal their interactive chemistry and bond strength is considered. Bulk properties examined include elastic and plastic behavior in the surficial regions, cohesive binding energies, crystal structures and crystallographic orientation. Materials examined with respect to interfacial adhesive interactions include silicon carbide, nickel zinc ferrite, manganese zinc ferrite, and aluminum oxide. The surfaces of the contacting solids are studied both in the atomic or molecularly clean state and in the presence of selected surface contaminants.

  11. Characterization of fatigue damage in adhesively bonded lap joints through dynamic, full-spectral interrogation of fiber Bragg grating sensors: 1. Experiments

    In this study we measure the in situ response of a fiber Bragg grating (FBG) sensor embedded in the adhesive layer of a single composite lap joint, subjected to harmonic excitation after fatigue loading. After a fully reversed cyclic fatigue loading is applied to the composite lap joint, the full-spectral response of the sensor is interrogated at 100 kHz during two loading conditions: with and without an added harmonic excitation. The full-spectral information avoided dynamic measurement errors often experienced using conventional peak wavelength and edge filtering techniques. The short-time Fourier transform (STFT) is computed for the extracted peak wavelength information to reveal time-dependent frequencies and amplitudes of the dynamic FBG sensor response. The dynamic response of the FBG sensor indicated a transition to strong nonlinear dynamic behavior as fatigue-induced damage progressed. The ability to measure the dynamic response of the lap joint through sensors embedded in the adhesive layer can provide in situ monitoring of the lap joint condition. (paper)

  12. Resistência ao cisalhamento de um selante associado a componentes de um sistema adesivo dental Shear bond strength of an enamel sealant using components of a dental adhesive system

    Zilda Maria MUSSOLINO

    1998-10-01

    significant differences in the shear bond strength of the sealant when the Probond Adhesive System was applied with or without "primer". The shear bond strength of enamel sealant was higher in the incisal third than in the cervical third.

  13. Efficient C-O and C-N bond forming cross-coupling reactions catalyzed by core-shell structured Cu/Cu2O nanowires

    Elshewy, Ahmed M.

    2013-12-01

    Oxygen and Nitrogen containing compounds are of utmost importance due to their interesting and diverse biological activities. The construction of the C-O and C–N bonds is of significance as it opens avenues for the introduction of ether and amine linkages in organic molecules. Despite significant advancements in this field, the construction of C-O and C–N bonds is still a major challenge for organic chemists, due to the involvement of harsh reaction conditions or the use of expensive catalysts or ligands in many cases. Thus, it is a challenge to develop alternative, milder, cheaper and more reproducible methodologies for the construction of these types of bonds. Herein, we introduce a new efficient ligand free catalytic system for C-O and C-N bond formation reactions.

  14. The Effects of Silicone Contamination on Bond Performance of Various Bond Systems

    Anderson, G. L.; Stanley, S. D.; Young, G. L.; Brown, R. A.; Evans, K. B.; Wurth, L. A.

    2012-01-01

    The sensitivity to silicone contamination of a wide variety of adhesive bond systems is discussed. Generalizations regarding factors that make some bond systems more sensitive to contamination than others are inferred and discussed. The effect of silane adhesion promoting primer on the contamination sensitivity of two epoxy/steel bond systems is also discussed.

  15. Tensile bond strength between different glass ionomer cement and composite resin using three adhesive systems
    Avaliação da resistência de união interfacial entre diferentes cimentos de ionômero de vidro e resina composta, usando três sistemas adesivos

    Patrícia Dias; Raul Santos de Sá; Jorge Augusto César; Guilherme Augusto de Barros Nolasco; Fátima Cristina de Sá

    2005-01-01

    The purpose of this study was to evaluate the tensile bond strength (TBS) among a Composite Resin (Filtek Z250) and six conventional Glass Ionomer Cements, three used for lining (Bioglass F, Vidrion F and Glass Ionomer L.C.) and three for restorations (Ketac Fil, Vidrion R and Glass Ionomer type II) etched and non etched, using three adhesive systems (Single Bond, Bond 1 and Stae). Thirty-six groups were made, ten samples for each group, totalizing 360 specimens. There were significant differ...

  16. Silane primers rather than heat treatment contribute to adhesive bonding between tri-n-butylborane resin and a machinable leucite-reinforced ceramic

    Sakai, Miyuki; Taira, Yohsuke; Sawase, Takashi

    2011-01-01

    The purpose of the present study was to evaluate the effects of silane primers with and without heat treatment on bonding between a resin and a leucite-reinforced ceramic (GN-Ceram). Six dental primers (GC Ceramic Primer, GP; Clearfl Ceramic Primer, CP; RelyX Ceramic Primer, RP; Tokuso Ceramic Primer, TP; Shofu Porcelain Primer, SP; and Porcelain Liner M, PM) and five experimental primers (MDS, MTS, MDES, MTES, and ATS) were evaluated. GN-Ceram specimen was primed, heated at 100°C for 60 min ...

  17. Photovoltaic module with adhesion promoter

    Xavier, Grace

    2013-10-08

    Photovoltaic modules with adhesion promoters and methods for fabricating photovoltaic modules with adhesion promoters are described. A photovoltaic module includes a solar cell including a first surface and a second surface, the second surface including a plurality of interspaced back-side contacts. A first glass layer is coupled to the first surface by a first encapsulating layer. A second glass layer is coupled to the second surface by a second encapsulating layer. At least a portion of the second encapsulating layer is bonded directly to the plurality of interspaced back-side contacts by an adhesion promoter.

  18. Surgical adhesives

    I. A. THOMAZINI-SANTOS

    2001-12-01

    Full Text Available The authors have performed a literature review of surgical adhesives, such as cyanoacrylate, collagen gelatin, and fibrin glue. They have included different types of commercial and non-commercial fibrin sealants and have reported on the different components in these adhesives, such as fibrinogen, cryoprecipitate, bovine thrombin, and thrombin-like fraction of snake venom.

  19. A simplified indirect bonding technique

    Radha Katiyar

    2014-01-01

    Full Text Available With the advent of lingual orthodontics, indirect bonding technique has become an integral part of practice. It involves placement of brackets initially on the models and then their transfer to teeth with the help of transfer trays. Problems encountered with current indirect bonding techniques used are (1 the possibility of adhesive flash remaining around the base of the brackets which requires removal (2 longer time required for the adhesive to gain enough bond strength for secure tray removal. The new simplified indirect bonding technique presented here overcomes both these problems.

  20. Effect of Green Or Desensitizer on Shear Bond Strength of Adhesive Agents to Dentin%极固宁对水门汀与牙本质间剪切强度的影响

    秦玉杰; 程祥荣; 徐东选; 陈小冬

    2011-01-01

    目的:评价极固宁脱敏剂对5种水门汀剪切强度的影响.方法:收集双尖牙30颗.包埋牙齿,暴露牙本质面,用水砂纸打磨牙本质面.所有牙齿被分为实验组和对照组.实验组的牙本质面首先用极固宁脱敏处理,然后分别用5种水门汀将树脂小柱粘在牙本质表面.对照组的牙本质不涂脱敏剂,使用前述提到的水门汀粘固树脂小柱.所有试样放在37℃水浴中浸泡24 h后测量剪切强度.结果:极固宁脱敏剂没有显著降低聚羧酸锌水门汀和玻璃离子水门汀的剪切强度,但却会使磷酸锌水门汀的剪切强度大幅下降.极固宁也使树脂加强玻璃离子水门汀和树脂水门汀的粘接强度下降.结论:极固宁对磷酸锌水门汀、树脂加强玻璃离子水门汀、树脂水门汀与牙本质间粘接强度有不利影响,对聚羧酸锌水门汀和玻璃离子水门汀与牙本质间粘接强度无不利影响.%Objective: To investigate the effect of Green Or desensitizer on shear bond strength of five adhesive a-gents to dentin. Methods: Thirty human premolars were used. Dentin surfaces were ground with silicon carbide abrasive papers. Teeth were randomly divided into two groups: the tested group and the control group. For the tested group, dentin surfaces were treated with Green Or desensitizer, then Solidex cylinders were positioned over the dentin surface with five cements respectively. For the control group, no desensitizer was applied, resin cylinders were bonded with cements mentioned above. Shear bond strengths were detemined. Results: The results indicate that Green Or desensitizer-treated dentin did not affect the shear bond strength of glass ionomer or polycarboxylate cements, but produced a large decrease in the shear bond strength of zinc phosphate. For resin-forced glass ionomer and resin luting agents, the application of Green Or desensitizer significantly reduced the shear bond strength of both materials. Conclusion: Green Or

  1. The hydrogen bond network structure within the hydration shell around simple osmolytes: Urea, tetramethylurea, and trimethylamine-N-oxide, investigated using both a fixed charge and a polarizable water model

    Kuffel, Anna; Zielkiewicz, Jan

    2010-07-01

    Despite numerous experimental and computer simulation studies, a controversy still exists regarding the effect of osmolytes on the structure of surrounding water. There is a question, to what extent some of the contradictory results may arise from differences in potential models used to simulate the system or parameters employed to describe physical properties of the mixture and interpretation of the results. Bearing this in mind, we determine two main aims of this work as follows: description of the water-water hydrogen bond network structure within the solvation layer around solute molecules (urea, trimethylamine-N-oxide, and tetramethylurea), and also comparison of rigid simple point charges (SPC) and polarizable (POL3) models of water. The following quantities have been examined: radial distribution functions of water molecules around the investigated solutes, both local and overall characteristics of the hydrogen bond network structure (using recently elaborated method), along with estimation of the mean energy of a single hydrogen bond, and also the probability distributions which describe the orientation of a single water particle plane relatively to the center of mass of the solute molecule. As an independent method for the evaluation of the degree of changes in local structural ordering, a harmonic approximation has been adopted to estimate the absolute entropy of water. It was found that within the solvation shell of the investigated solutes, the structure of hydrogen bond network changes only slightly comparing to bulk water. Therefore, we conclude that the investigated osmolyte molecules do not disturb significantly the structure of surrounding water. This conclusion was also confirmed by calculations of the absolute entropy of water using a harmonic approximation. In the immediate vicinity of the solutes, we observe that the water-water hydrogen bonds are slightly more stable; they are slightly less distorted and a little shorter than in bulk water

  2. Electronic Structure and Bonding of Icosahedral Core-Shell Gold-Silver Nanoalloy Clusters Au_(144-x)Ag_x(SR)_60

    Malola, Sami; Häkkinen, Hannu

    2011-01-01

    Atomically precise thiolate-stabilized gold nanoclusters are currently of interest for many cross-disciplinary applications in chemistry, physics and molecular biology. Very recently, synthesis and electronic properties of "nanoalloy" clusters Au_(144-x)Ag_x(SR)_60 were reported. Here, density functional theory is used for electronic structure and bonding in Au_(144-x)Ag_x(SR)_60 based on a structural model of the icosahedral Au_144(SR)_60 that features a 114-atom metal core with 60 symmetry-...

  3. Effect of sodium hypochlorite on the bond strength of an adhesive system to superficial and deep dentin Efeito do hipoclorito de sódio na resistência de união de um sistema adesivo na dentina superficial e profunda

    Ninoshka Uceda-Gómez; Alessandra Reis; Marcela Rocha de Oliveira Carrilho; Alessandro Dourado Loguercio; Leonardo Eloy Rodriguez Filho

    2003-01-01

    The objective of this study was to evaluate the bond strength to superficial (SU) and deep (D) dentin, accessed via apical (DA) or occlusal (DO), using One-Step adhesive system applied according to the manufacturer's instructions (C) or following deproteinization with 10% sodium hypochlorite (H) for 60s, after acid etching. Three sound extracted human molars were prepared for each experimental condition. Restorations were performed using Z100 in 2mm increments, each one being light-cured for ...

  4. The curative effect observation of super adhesive bonding of light cured composite resin inlay in the repair of deciduous teeth Ⅱ complex cavities%超级黏接剂黏接光固化复合树脂嵌体在修复乳牙Ⅱ类复面洞型的疗效观察

    辜赵娜

    2015-01-01

    目的:观察超级黏接剂黏接材料黏接复合树脂嵌体在修复乳牙Ⅱ类洞型的临床疗效。方法:收治乳牙Ⅱ类洞型患者18例,采用超级黏接剂黏接材料黏接复合树脂嵌体进行修复治疗,观察临床效果。结果:经过随访观察,用超级黏接剂黏接材料黏接光固化复合树脂嵌体在口腔无脱落,嵌体边缘继发龋发生率4.8%。结论:使用超级黏接剂材料黏接光固化复合树脂嵌体具有很好防止脱落和防止继发龋的效果。%Objective:To explore the curative effect observation of super adhesive bonding of light cured composite resin inlay in the repair of deciduous teeth Ⅱ complex cavities.Methods:18 patients with deciduous teeth Ⅱ complex cavities were selected. They were treated by super adhesive bonding of light cured composite resin inlay.We observed the clinical effect.Results:After follow-up observation,with super adhesive bonding of light cured composite resin inlay,there was no shedding in oral,and secondary caries incidence at inlay edge was 4.8%.Conclusion:Using super adhesive bonding of light cured composite resin inlay was good to prevent the shedding and prevent the incidence of secondary caries.

  5. On local panel distortions due to hot-curing adhesives

    Priesnitz, K.

    2015-01-01

    For many joining applications, adhesive bonding is the favoured method. It provides the ability to join dissimilar materials such as metals and plastics. Adhesive bonds can be formed over large flange areas subsequently increasing the overall stiffness of the assembly. In some cases, however, the bo

  6. Marine Bioinspired Underwater Contact Adhesion.

    Clancy, Sean K; Sodano, Antonio; Cunningham, Dylan J; Huang, Sharon S; Zalicki, Piotr J; Shin, Seunghan; Ahn, B Kollbe

    2016-05-01

    Marine mussels and barnacles are sessile biofouling organisms that adhere to a number of surfaces in wet environments and maintain remarkably strong bonds. Previous synthetic approaches to mimic biological wet adhesive properties have focused mainly on the catechol moiety, present in mussel foot proteins (mfps), and especially rich in the interfacial mfps, for example, mfp-3 and -5, found at the interface between the mussel plaque and substrate. Barnacles, however, do not use Dopa for their wet adhesion, but are instead rich in noncatecholic aromatic residues. Due to this anomaly, we were intrigued to study the initial contact adhesion properties of copolymerized acrylate films containing the key functionalities of barnacle cement proteins and interfacial mfps, for example, aromatic (catecholic or noncatecholic), cationic, anionic, and nonpolar residues. The initial wet contact adhesion of the copolymers was measured using a probe tack testing apparatus with a flat-punch contact geometry. The wet contact adhesion of an optimized, bioinspired copolymer film was ∼15.0 N/cm(2) in deionized water and ∼9.0 N/cm(2) in artificial seawater, up to 150 times greater than commercial pressure-sensitive adhesive (PSA) tapes (∼0.1 N/cm(2)). Furthermore, maximum wet contact adhesion was obtained at ∼pH 7, suggesting viability for biomedical applications. PMID:27046671

  7. Adhesion and multi-materials

    Adhesion is a multidisciplinary science relevant to many practical fields. The main application of adhesion is bonding by adhesives. This technique is widely used in the industrial world and more specifically in the advanced technical domains. Adhesion is also involved in multi-component materials such as coatings, multilayer materials, polymer blends, composite materials... The multidisciplinary aspect of adhesion is well demonstrated by considering the wide variety of concepts, models and theories proposed for its description. An example of the adhesion between a fiber and a matrix in a composite material will lead to a general model relating the molecular properties of the interface to its capacity of stress transfer and hence to the macroscopic mechanical properties of the composite. This relationship is valid whatever the fiber (glass, carbon, polymeric) or the polymer matrix (thermoplastics, thermosetting). Any deviation from this model can be attributed to the existence of an interfacial zone or interphase exhibiting properties, mainly mechanical properties, different from the bulk matrix. Two examples are examined: the first one deals with the creation of a trans crystalline interphase in a semi-crystalline thermoplastic matrix and the second one is concerned with the formation of a pseudo glassy interphase in an elastomer matrix. These examples stress the need for complementary approaches in the understanding of adhesion phenomena at different levels of knowledge, from molecular to macroscopic. They also show how important it is to understand the mechanisms of formation of inter phases in order to be able to master the performance of multicomponent materials. (Author)

  8. Drastic Improvements in Bonding of Fiber Reinforced Multifunctional Composites Project

    National Aeronautics and Space Administration — Achievement of a dramatic increase in the bond strength in the adhesive and composite/adhesive interfaces of existing fiber reinforced composite material joints and...

  9. Evaluation of the tensile bond strength of an adhesive system self-etching in dentin irradiated with Er:YAG laser; Avaliacao da resistencia a tracao de um sistema adesivo self-etching em dentina irradiada com Er:YAG laser

    Mello, Andrea Malluf Dabul de

    2000-07-01

    Since Buonocore (1955), several researchers have been seeking for the best adhesive system and treatment for the enamel and dentin surfaces. The use of the acid has been presented as one of the best techniques of dentin conditioning , because this promotes the removal of the 'smear layer and exhibition of dentinal structure, for a best penetration and micro- retention of the adhesive system. However, some conditioning methods have been appearing in the literature, for the substitution or interaction with the acid substances, as the laser. The objective of this work is to evaluate the tensile bond strength of the adhesive system self-etching' associated to a composed resin, in dentin surfaces conditioned with the Er:YAG laser. For this study, freshly extracted human teeth were used and in each one the dentinal surfaces , which were treated with three sandpapers of different granulations (120,400,600), to obtain a standard of the smear layer, before the irradiation of the laser and of the restoring procedure. After these procedures the specimens were storage in distilled water at 37 deg C for 24 hours. Soon after, they were submitted to the tensile strength test .After analyzing the results, we can concluded that the use of the Er:YAG laser can substitute the drill without the need of conditioning, when using the adhesive system 'self-etching' in the dentinal surfaces because there was a decline in the strength of adhesion in the groups conditioned with the laser. (author)

  10. Evaluation of bond strength of orthodontic brackets without enamel etching

    Boruziniat, Alireza; Khazaei, Yegane; Motaghi, Shiva; Moghaddas, Mohmmadjavad

    2015-01-01

    Background To compare the shear bond strength of brackets with and without enamel etching. Material and Methods In this study, 60 sound premolars were randomly divided into four different groups: 1- TXE group: Enamel etching+Transbond XT adhesive+ Transbond XT composite. 2- TXS group: Transbond plus self-etch adhesive+ Transbond XT composite. 3- PQ1E group: Enamel etching+ PQ1 adhesive+ Transbond XT composite. 4- PQ1 group: PQ1 adhesive+ Transbond XT composite. The shear bond strengths of bra...

  11. Bacterial Adhesion & Blocking Bacterial Adhesion

    Vejborg, Rebecca Munk

    2008-01-01

    parameters, which influence the transition from a planktonic lifestyle to a sessile lifestyle, have been studied. Protein conditioning film formation was found to influence bacterial adhesion and subsequent biofilm formation considerable, and an aqueous extract of fish muscle tissue was shown to...... tract to the microbial flocs in waste water treatment facilities. Microbial biofilms may however also cause a wide range of industrial and medical problems, and have been implicated in a wide range of persistent infectious diseases, including implantassociated microbial infections. Bacterial adhesion is...... the first committing step in biofilm formation, and has therefore been intensely scrutinized. Much however, still remains elusive. Bacterial adhesion is a highly complex process, which is influenced by a variety of factors. In this thesis, a range of physico-chemical, molecular and environmental...

  12. Comparison of shear bond strength of amalgam bonded to primary and permanent dentin

    Mahdi S; Bahman S; Arghavan A; Fatemeh M

    2008-01-01

    Amalgam′s non-adhesive characteristics necessitate cavity preparations incorporating retentive features, which often require the removal of non-carious tooth structure. Use of adhesives beneath amalgam restorations, would be helpful to overcome this disadvantage. This study was undertaken to compare the mean shear bond strength of amalgam bonded to primary and permanent dentin, to evaluate the efficacy of amalgam adhesives in pediatric dentistry.27 primary and 28 permanent posterior te...

  13. On the mechanical properties of bovine serum albumin (BSA) adhesives.

    Berchane, N S; Andrews, M J; Kerr, S; Slater, N K H; Jebrail, F F

    2008-04-01

    Biological adhesives, natural and synthetic, are of current active interest. These adhesives offer significant advantages over traditional sealant techniques, in particular, they are easier to use, and can play an integral part in the healing mechanism of tissue. Thus, biological adhesives can play a major role in medical applications if they possess adequate mechanical behavior and stability over time. In this work, we report on the method of preparation of bovine serum albumin (BSA) into a biological adhesive. We present quantitative measurements that show the effect of BSA concentration and cross-linker content on the bonding strength of BSA adhesive to wood. A comparison is then made with synthetic poly(glycidyl methacrylate) (PGMA) adhesive, and a commercial cyanoacrylate glue, which was used as a control adhesive. In addition, BSA samples were prepared and characterized for their water content, tensile strength, and elasticity. We show that on dry surface, BSA adhesive exhibits a high bonding strength that is comparable with non-biological commercial cyanoacrylate glues, and synthetic PGMA adhesive. Tensile testing on wet wood showed a slight increase in the bonding strength of BSA adhesive, a considerable decrease in the bonding strength of cyanoacrylate glue, and negligible adhesion of PGMA. Tests performed on BSA samples demonstrate that initial BSA concentration and final water content have a significant effect on the stress-strain behavior of the samples. PMID:18197367

  14. 不同表面处理对氧化锆陶瓷与自粘结树脂粘结强度的影响%Influence of different surface treatments on shear bond strength of self-adhesive resin bonding to zirconia ceramic

    吴雪勋; 郭庆平; 王洋; 缪颖

    2015-01-01

    Objective This study is to evaluate Influence of different surface treatments on shear bond strength(SBS) of self-adhesive resin bonding to zirconia ceramic. Methods 80 square-like zirconia samples were polished and randomly assigned in four groups according to different surface treat⁃ments.Group A:air-abraded and silica coating;group B:Er:YAG laser irradiation;group C:laser fol⁃lowed by air-abraded and silica coating;group D:no treatment.Each group was divided into two sub⁃groups(a and b) according the resin tested: BiFixSE and Clearfil SA.A shear bond strength test was performed using a universal testing machine. Results Bonded with BiFixSE,group Ca showed no dif⁃ference with group Aa in SBS(P>0.05),but they both showed higher SBS than group Ba(P<0.05), and group Ba showed higher SBS than group Da(P<0.05). Bonded with Clearfil SA,it was group Cb, Ab, Bb,Db aranging from high to low. In group C,Clearfil SA showed higher SBS than BiFixSE( P<0.05). Concluison Although Er:YAG laser irradiation alone showed lower SBS,it can enhance bonding strength by combined application.%目的:研究不同表面处理方法对氧化锆陶瓷与两种自粘结树脂粘结强度的影响,为临床上氧化锆陶瓷修复体粘结选择合适的表面处理方法和粘结树脂提供参考。方法:将80个氧化锆瓷片随机分为A、B、C、D四组。A组采用喷砂+硅涂层法,B组采用Er:YAG激光蚀刻,C组先Er:YAG激光蚀刻后再用喷砂+硅涂层法。D组作为对照组不做处理。每组再分为a、b两个组,分别用BifixSE自粘结树脂和Clearfil SA自粘结树脂粘结,最后置于万能材料力学测试机测得剪切强度。结果:使用BifixSE自粘结树脂粘结时,Ca组与Aa组比较,差异无统计学意义(P>0.05);但两组均大于Ba组,差异有统计学意义(P<0.05),Ba组大于Da组(P<0.05),差异有统计学意义。使用Clearfil SA自粘结树脂粘结时(b组),各组粘结强

  15. Development of the Automated Bonding Robot for Space Solar Cells

    WU Yue-xin; ZHAO Yan-zheng; FU Zhuang; ZHAO Hui; LUO Zhen

    2007-01-01

    The bonding process of space solar cells is a very complicated task undertaken by manual labor before. An automatic approach based on robot technology is presented to deal with the difficult problem. The architecture of the bonding robot for space solar cells is described. The two processes carried out by the robot, adhesive dispensing and cover-glass bonding, are studied. Based on the mechanical model, the flow velocity field of the adhesive in needles is obtained and the cover-glass bonding theory is interpreted. According to the studies, the thickness of the adhesive can be controlled accurately by robot and bubbles can be avoided coming about inside the adhesive.

  16. Avaliação do Índice de Remanescente Adesivo utilizando braquetes com e sem tratamento na base e a interação com três sistemas de colagem Evaluation of Adhesive Remnant Index using conventional mesh bases and sandblasted orthodontic bracket bases and three bonding systems

    Lilian Maria Brisque Pignatta

    2009-02-01

    Full Text Available OBJETIVO: avaliar o Índice de Remanescente Adesivo (IRA em dentes bovinos após a descolagem de braquetes com e sem tratamento na base. METODOLOGIA: foram utilizados três sistemas de colagem ortodôntica para os dois padrões de base. Os dentes bovinos foram divididos em seis grupos de 40, de acordo com a base do braquete e o sistema de colagem. Vinte e quatro horas após a colagem foram realizados os testes de compressão em uma máquina de ensaios. A avaliação do IRA foi realizada em um estereomicroscópio por três examinadores calibrados. Foi utilizado o teste não paramétrico de Kruskal-Wallis, seguido do método de Dunn, para fazer as comparações múltiplas entre todos os grupos. RESULTADOS E CONCLUSÕES: observou-se que o tratamento das bases dos braquetes com óxido de alumínio não foi determinante para o aumento da adesividade entre o braquete e o adesivo. O grupo em que se utilizou braquetes com tratamento na base e adesivo TXT (3M-Unitek + Transbond Plus SEP (3M-Unitek apresentou a maior parte das fraturas na interface dente-adesivo (escore 4.AIM: To assess the Adhesive Remnant Index (ARI in bovine teeth after debonding mesh bases and sandblasted orthodontic bracket bases. METHODS: Were used three bonding systems for the two standards of base. The bovine teeth were divided into 6 groups of 40, according to the bracket base and to the bonding system. Twenty four hours after bonding they had been carried through shear bond strength tests in a universal testing machine. The assessment of ARI was performed in a stereomicroscopy by three calibrated examiners. It was used the non-parametric Kruskall-Wallis test, followed by Dunn's method, to do the multiple comparisons among all groups. RESULTS AND CONCLUSIONS: It was observed that the aluminum oxide sandblasting bracket bases was not determinative to the increase of the adhesiveness between bracket and adhesive. The group where it was used sandblasted orthodontic bracket bases and

  17. Thickness value of fireproof coating for slabs strengthened with Carbon Fiber Sheet bonded with an inorganic adhesive%无机胶粘贴碳纤维布加固板防火涂层厚度取值

    万夫雄; 郑文忠

    2012-01-01

    For keeping strengthening role of Carbon Fiber Sheet(CFS) bonded with an inorganic adhesive to insure fire safe of structure,thick-typed fireproof coating is needed for protecting CFS.Considering deformation limit of strengthened slabs in fire,temperature on bottom surface of slabs is limited to 415 ℃ by trial calculation of deformation by ABAQUS.By analysis of temperature field of strengthened slabs by ABAQUS,fireproof coating thickness,heat conductivity coefficient and fire duration are the main factors affecting temperature on bottom surface of strengthened slabs,so key factors affecting fireproof coating thickness are heat conductivity coefficient and fire duration.Based on that,in terms of fire endurance and thermal conductivity coefficient of coating,and considering actual construction demand,advised values of fireproof coating thickness are proposed in terms of different type of coating.%为确保火灾下用无机胶粘贴的碳纤维布能正常发挥加固作用,保证结构安全,需要选用一定厚度的厚型防火涂料作为碳纤维布的防火保护层.基于对加固板高温变形限制的考虑,采用ABAQUS对其高温变形进行试算,提出以板底温度415℃作为控制温度计算涂料厚度的原则.采用ABAQUS对加固板温度场进行分析,表明涂料厚度、导热系数以及受火时间是影响板底温度的主要因素,因而决定涂料保护层厚度的关键因素为导热系数和受火时间.在此基础上,按耐火时间和涂料导热系数的不同,分涂料品种并考虑相应构造要求的基础上,给出基于温度控制的防火涂料保护层厚度取值建议.

  18. Paint-Bonding Improvement for 2219 Aluminum Alloy

    Daech, Alfred F.; Cibula, Audrey Y.

    1987-01-01

    Bonding of adhesives and primers to 2219 aluminum alloy improved by delaying rinse step in surface-treatment process. Delaying rinse allows formation of rougher surface for stronger bonding and greater oxide buildup.

  19. Quantifying adhesion energy of mechanical coatings at atomistic scale

    Coatings of transition metal compounds find widespread technological applications where adhesion is known to influence or control functionality. Here, we, by first-principles calculations, propose a new way to assess adhesion in coatings and apply it to analyze the TiN coating. We find that the calculated adhesion energies of both the (1 1 1) and (0 0 1) orientations are small under no residual stress, yet increase linearly once the stress is imposed, suggesting that the residual stress is key to affecting adhesion. The strengthened adhesion is found to be attributed to the stress-induced shrinkage of neighbouring bonds, which results in stronger interactions between bonds in TiN coatings. Further finite elements simulation (FEM) based on calculated adhesion energy reproduces well the initial cracking process observed in nano-indentation experiments, thereby validating the application of this approach in quantifying adhesion energy of surface coating systems.

  20. Biomimetic Adhesive Materials Containing Cyanoacryl Group for Medical Application

    Sueng Hwan Jo

    2014-10-01

    Full Text Available For underwater adhesives with biocompatible and more flexible bonds using biomimetic adhesive groups, DOPA-like adhesive molecules were modified with cyanoacrylates to obtain different repeating units and chain length copolymers. The goal of this work is to copy the mechanisms of underwater bonding to create synthetic water-borne underwater medical adhesives through blending of the modified DOPA and a triblock copolymer (PEO-PPO-PEO for practical application to repair wet living tissues and bones, and in turn, to use the synthetic adhesives to test mechanistic hypotheses about the natural adhesive. The highest values in stress and modulus of the biomimetic adhesives prepared in wet state were 165 kPa and 33 MPa, respectively.

  1. Shear bond strength, failure modes, and confocal microscopy of bonded amalgam restorations.

    Cianconi, Luigi; Conte, Gabriele; Mancini, Manuele

    2011-01-01

    This study evaluated the shear bond strength, failure modes, and confocal microscopy of two different amalgam alloy restorations lined with five adhesive systems. Two regular-set high-copper dental amalgam alloys, Amalcap Plus and Valiant Ph.D, and five commercially available adhesive systems were selected. One hundred and twenty freshly-extracted human third molars were used for the study. The results were statistically evaluated using two-factor analysis of variance (ANOVA). The shear bond strength (SBS) of amalgam to dentin was significantly affected by both the adhesive (pValiant Ph.D, 31 of 50 exhibited adhesive failure, and 19 displayed mixed failure. Laser optical microscopy (OM) of the bonded interface revealed the presence of a good hybrid layer was evident in all experimental groups. Higher bond strengths were measured for four of the five adhesives when used in combination with the spherical alloy. PMID:21383518

  2. Effects of surface treatment and adhesive application on shear bond strength between zirconia and enamel%表面处理及粘结剂对氧化锆与牙釉质间剪切粘结强度的影响

    李颖慧; 吴补领; 孙风阳

    2013-01-01

    目的 研究表面喷砂处理及不同正畸粘结剂对氧化锆陶瓷与牙釉质间剪切粘结强度的影响.方法 40颗离体上颌第一前磨牙,应用计算机辅助设计与计算机辅助制作系统设计和制作粘结面与牙面紧密贴合的个性化氧化锆陶瓷试件.将试件随机分为4组,分别选择粘结面喷砂处理和粘结面无处理,选择京津釉质粘结剂和3M Transbond XT光固化粘结剂.按要求粘结24 h后,万能材料试验机测定剪切粘结强度,并进行统计学分析.结果 喷砂组剪切粘结强度显著高于未喷砂组(P<0.05),两种粘结剂的剪切粘结强度无显著差异(P>0.05).结论 表面喷砂处理后,无论使用京津釉质粘结剂或是3M Transbond XT光固化粘结剂,氧化锆陶瓷与牙釉质间均可获得足够的剪切粘结强度.%Objective To evaluate the effects of sandblasting and different orthodontic adhesives on shear bond strength between zirconia and enamel. Methods Zirconia ceramic samples were designed and manufactured for 40 extracted human maxillary first premolars with CAD/CAM system. The samples were randomized into 4 groups for surface treatment with sandblasting and non-treated with adhesives of 3M Transbond XT or Jingjin dental enamel bonding resin. After 24 h of bonded fixation, the shear bond strengths were measured by universal mechanical testing machine and analyzed with factorial variance analysis. Results The shear bond strength was significantly higher in sandblasting group than in untreated group (P0.05). Conclusion The shear bond strength between zirconia and enamel is sufficient after sandblasting regardless of the application of either adhesive.

  3. Weld bonding of stainless steel

    Santos, I. O.; Zhang, Wenqi; Goncalves, V.M.;

    2004-01-01

    This paper presents a comprehensive theoretical and experimental investigation of the weld bonding process with the purpose of evaluating its relative performance in case of joining stainless steel parts, against alternative solutions based on structural adhesives or conventional spot-welding. The...... overall assessment of the weld bonding process is made using several commercial adhesives with varying working times under different surface conditions. The quality of the resulting joints is evaluated by means of macroetching observations, tension-shear tests and peel tests. The theoretical investigation...

  4. Ultrasonic Characterization of Interfaces in Composite Bonds

    Wang, N.; Lobkis, O. I.; Rokhlin, S. I.; Cantrell, J. H.

    2010-01-01

    The inverse determination of imperfect interfaces from reflection spectra of normal and oblique incident ultrasonic waves in adhesive bonds of multidirectional composites is investigated. The oblique measurements are complicated by the highly dispersed nature of oblique wave spectra at frequencies above 3MHz. Different strategies for bond property reconstruction, including a modulation method, are discussed. The relation of measured interfacial spring density to the physico-chemical model of a composite interface described by polymer molecular bonds to emulate loss of molecular strength on an adhesive composite interface is discussed. This potentially relates the interfacial (adhesion) strength (number of bonds at the adhesive substrate interface) to the spring constant (stiffness) area density (flux), which is an ultrasonically measurable parameter.

  5. Ultrasonic characterization of interfaces in composite bonds

    The inverse determination of imperfect interfaces from reflection spectra of normal and oblique incident ultrasonic waves in adhesive bonds of multidirectional composites is investigated. The oblique measurements are complicated by the highly dispersed nature of oblique wave spectra at frequencies above 3MHz. Different strategies for bond property reconstruction, including a modulation method, are discussed. The relation of measured interfacial spring density to the physico-chemical model of a composite interface described by polymer molecular bonds to emulate loss of molecular strength on an adhesive composite interface is discussed. This potentially relates the interfacial (adhesion) strength (number of bonds at the adhesive substrate interface) to the spring constant (stiffness) area density (flux), which is an ultrasonically measurable parameter.

  6. Permeability of Dental Adhesives – A SEM Assessment

    Malacarne-Zanon, Juliana; de Andrade e Silva, Safira M.; Linda WANG; de Goes, Mario F.; Martins, Adriano Luis; Narvaes-Romani, Eliene O.; Anido-Anido, Andrea; Carrilho, Marcela R. O.

    2010-01-01

    Objectives: To morphologically evaluate the permeability of different commercial dental adhesives using scanning electron microscopy. Methods: Seven adhesive systems were evaluated: one three-step system (Scotchbond Multi-Purpose - MP); one two-step self-etching primer system (Clearfil SE Bond – SE); three two-step etch-and-rinse systems (Single Bond 2 – SB; Excite – EX; One-Step – OS); and two single-step self-etching adhesives (Adper Prompt – AP; One-Up Bond F – OU). The mixture of primer a...

  7. Adhesion of Dental Materials to Tooth Structure

    Mitra, Sumita B.

    2000-03-01

    The understanding and proper application of the principles of adhesion has brought forth a new paradigm in the realm of esthetic dentistry. Modern restorative tooth procedures can now conserve the remaining tooth-structure and also provide for the strengthening of the tooth. Adhesive restorative techniques call for the application and curing of the dental adhesive at the interface between the tooth tissue and the filling material. Hence the success of the restoration depends largely on the integrity of this interface. The mechanism of adhesion of the bonding materials to the dental hard tissue will be discussed in this paper. There are four main steps that occur during the application of the dental adhesive to the oral hard tissues: 1) The first step is the creation of a microstructure in the tooth enamel or dentin by means of an acidic material. This can be through the application of a separate etchant or can be accomplished in situ by the adhesive/primer. This agent has to be effective in removing or modifying the proteinaceous “smear” layer, which would otherwise act as a weak boundary layer on the surface to be bonded. 2) The primer/adhesive must then be able to wet and penetrate the microstructure created in the tooth. Since the surface energies of etched enamel and that of etched dentin are different finding one material to prime both types of dental tissues can be quite challenging. 3) The ionomer types of materials, particularly those that are carboxylate ion-containing, can chemically bond with the calcium ions of the hydroxyapatite mineral. 4) Polymerization in situ allows for micromechanical interlocking of the adhesive. The importance of having the right mechanical properties of the cured adhesive layer and its role in absorbing and dissipating stresses encountered by a restored tooth will also be discussed.

  8. FINITE ELEMENT ANALYSIS OF WOOD ADHESIVE JOINTS

    Thomas GEREKE

    2016-03-01

    Full Text Available Engineered wood products such as glulam or cross-laminated timber are widely established in the construction industry. Their structural behaviour and reliability clearly bases on the adhesive bonding. In order to understand and improve the performance of glued wood members a finite element modelling of standard single lap shear samples was carried out. A three-dimensional model of a longitudinal tensile-shear specimen with quasi-centric load application was developed. The main influences of wood and adhesive parameters on structural performance were identified. Therefore, variations of the elasticity, the annual ring angle, fibre angle, and the interface zone and their effect on the occurring stresses in the adhesive bond line were investigated numerically. The adhesive bond line is most significantly sensitive to the Young´s modulus of the adhesive itself. A variation of the fibre angle of the glued members in the standard test is an essential criterion and to be considered when preparing lap shear specimens. A model with representation of early- and latewood gives a more detailed insight into wooden adhesive joints.

  9. [Resin-bonded fixed partial dentures

    Kreulen, C.M.; Creugers, N.H.J.

    2013-01-01

    A resin-bonded fixed partial denture is a prosthetic construction which can replace I or several teeth in an occlusal system and which comprises a pontic element which is adhesively attached to 1 or more abutment teeth. To compensate for the limited shear strength of the adhesive layer, the Jixed pa

  10. Thermal Characterization of Epoxy Adhesive by Hotfire Testing

    Spomer, Ken A.; Haddock, M. Reed; McCool, Alex (Technical Monitor)

    2001-01-01

    This paper describes subscale solid-rocket motor hot-fire testing of epoxy adhesives in flame surface bondlines to evaluate heat-affected depth, char depth and ablation rate. Hot-fire testing is part of an adhesive down-selection program on the Space Shuttle Solid Rocket Motor Nozzle to provide additional confidence in the down-selected adhesives. The current nozzle structural adhesive bond system is being replaced due to obsolescence. Prior to hot-fire testing, adhesives were tested for chemical, physical and mechanical properties, which resulted in the selection of two potential replacement adhesives, Resin Technology Group's TIGA 321 and 3M's EC2615XLW. Hot-fire testing consisted of four forty-pound charge (FPC) motors fabricated in configurations that would allow side-by-side comparison testing of the candidate replacement adhesives with the current RSRM adhesives. Results of the FPC motor testing show that: 1) the phenolic char depths on radial bondlines is approximately the same and vary depending on the position in the blast tube regardless of which adhesive was used, 2) the replacement candidate adhesive char depths are equivalent to the char depths of the current adhesives, 3) the heat-affected depths of the candidate and current adhesives are equivalent, and 4) the ablation rates for both replacement adhesives were equivalent to the current adhesives.

  11. Shell supports

    Almegaard, Henrik

    2004-01-01

    A new statical and conceptual model for membrane shell structures - the stringer system - has been found. The principle was first published at the IASS conference in Copenhagen (OHL91), and later the theory has been further developed (ALMO3)(ALMO4). From the analysis of the stringer model it can be...... concluded that all membrane shells can be described by a limited number of basic configurations of which quite a few have free edges....

  12. Comparing In Situ and Bulk Constitutive Properties of a Structural Adhesive

    Grohs, Joshua Walter

    2007-01-01

    In the continuing quest for more efficient designs, structural adhesives are being used in place of, or with, traditional fastening methods; however designing with adhesives is refined as traditional methods. To obtain the adhesive design properties, tests are often performed on bulk tensile and bonded shear specimens. Questions remain about the relationship between properties obtained from in situ adhesive joints and bulk adhesive specimens. As a result, an experimental plan was developed...

  13. Investigation of elevated temperature effects on multiple layer piezoelectric ultrasonic transducers with adhesive bondlines by self-heating

    Wu, Zhengbin; Cochran, Sandy; Wu, Bo

    2010-01-01

    In this chapter, the behaviour of adhesively-bonded multilayer piezoelectric ultrasonic transducers with two typical adhesives has been investigated under self-heating conditions. The material characteristic variation of high Curie temperature lead metaniobate piezoelectric cermaic, used to manufacture the multilayer structures, with different temperature were studied. The temperature rise and mechanical output characteristics of adhesively-bonded multilayer ultrasonic transducers resulted fr...

  14. Shelled opisthobranchs.

    Mikkelsen, Paula M

    2002-01-01

    In his contributions to the monographic series "Manual of Conchology", Henry Pilsbry reviewed the subgroup Tectibranchiata, comprising those opisthobranch snails that (at least primitively) still possess a shell (Pilsbry, 1894-1896). Exemplified by the Cephalaspidea (bubble shells), others included in this group at Pilsbry's time and since were Anaspidea (sea hares) and the shelled members of Notaspidea (side-gilled slugs) and Sacoglossa (leaf slugs). Pilsbry (and others since his time) considered tectibranchs to be the "root stock" from which more advanced gastropods such as Nudibranchia and Pulmonata were derived. Tectibranch systematics is firmly based on conchology and most species were originally described from empty shells. However, soft-anatomical characters were acknowledged quite early on as equally important in tectibranchs, due to the reduction of their shells and their evolutionary proximity to unshelled gastropods. Today, Tectibranchiata is not recognized as a natural taxon although the word "tectibranch" (like "prosobranch" and "mesogastropod") continues in vernacular use. Shelled opisthobranchs have been redistributed among various taxa, including several new ones--the unresolved basal opisthobranchs (Architectibranchia) and the "lower Heterobranchia", an enigmatic and currently much-studied group of families considered basal to all of Euthyneura (Opisthobranchia and landsnails (Pulmonata)). Despite their polyphyletic status, shelled opisthobranchs remain important subjects in evolutionary studies of gastropods--as the most basal members of nearly every opisthobranch clade and as organisms with mosaic combinations of primitive and derived features within evolutionary "trends" (e.g., loss of the shell, detorsion, concentration of the nervous system, ecological specialization, etc.). Although they play a pivotal role, the shelled opisthobranchs have received minimal attention in more comprehensive gastropod studies, often relegated to token

  15. Microleakage comparison of three types of adhesive systems versus GIC-based adhesive in class V composite restorations

    Mostafa Sadeghi

    2016-06-01

    Full Text Available Background and aims: New dentin bonding agents and techniques have been developed to reduce microleakage and create higher bond strength. This in-vitro study compared the microleakage of three resin-based adhesives versus a GIC-based adhesive on class V composite restorations.  Materials and Methods: Class V cavities were prepared on the buccal surfaces of 72 sound premolars, randomly assigned to six groups (n=12 and treated as follows: without any treatment (negative control group; total-etch (OptiBond Solo Plus; two-step self-etch (OptiBond XTR; one-step self-etch (OptiBond All-in-One and GIC-based adhesive (Fuji bond LC with pre-cure and co-cure techniques. The treated cavities were filled with a micro-hybrid resin composite (Point 4, Kerr. Following finishing and polishing procedures, the specimens were placed in 100% humidity, stored in distilled water, thermocycled and then immersed in a methylene blue, sectioned, evaluated for microleakage and scored on a 0 to 3 ordinal scale.  Results: None of the adhesives tested were capable of completely eliminating marginal microleakage. There were statistically significant differences among the test groups at occlusal margins; but at cervical margins were not. The Fuji Bond LC with co-cure and control groups had significantly greater microleakage scores at the occlusal margins. At the cervical margins, the bonded restorations with OptiBond XTR and OptiBond All-in-One adhesives presented significantly lower microleakage scores. Also, there were no significant differences between the resin adhesive groups both at occlusal and cervical margins. The microleakage scores at the cervical margins were markedly higher than the occlusal margins in the groups bonded with OptiBond Solo Plus and Fuji Bond LC with pre-cure. The differences between Fuji Bond LC adhesive with pre-cure and co-cure techniques were significant. Conclusion: This study encourages application of the Fuji bond LC adhesive with pre

  16. Dynamic force spectroscopy on multiple bonds: experiments and model

    Erdmann, T; Nassoy, P; Schwarz, U S

    2007-01-01

    We probe the dynamic strength of multiple biotin-streptavidin adhesion bonds under linear loading using the biomembrane force probe setup for dynamic force spectroscopy. Measured rupture force histograms are compared to results from a master equation model for the stochastic dynamics of bond rupture under load. This allows us to extract the distribution of the number of initially closed bonds. We also extract the molecular parameters of the adhesion bonds, in good agreement with earlier results from single bond experiments. Our analysis shows that the peaks in the measured histograms are not simple multiples of the single bond values, but follow from a superposition procedure which generates different peak positions.

  17. Avaliação da atividade antimicrobiana de adesivo ortodôntico associado a verniz de clorexidina e timol na colagem de braquetes Evaluation of antimicrobial activity of orthodontic adhesive associated with chlorhexidine-thymol varnish in bracket bonding

    Carolina Freire de Carvalho Calabrich

    2010-08-01

    Full Text Available OBJETIVO: avaliar a atividade antimicrobiana da associação de um adesivo ortodôntico com um verniz de clorexidina e timol. MÉTODOS: foram utilizados 32 pré-molares humanos divididos em 4 grupos. O grupo 1 consistiu do grupo controle, no qual o adesivo utilizado para a colagem do braquete não estava associado a nenhum agente antimicrobiano. Os grupos 2, 3 e 4 foram colados com um sistema adesivo associado a um verniz de clorexidina e timol. Os grupos 3 e 4 foram armazenados em água por 7 dias e 30 dias, respectivamente, enquanto os corpos de prova do grupo 2 foram, logo depois da colagem, colocados em ágar semeado com Streptococcus mutans por 48h a 37ºC. RESULTADOS: os grupos experimentais, com exceção do grupo controle, apresentaram atividade antimicrobiana com tendência de redução do seu potencial de ação com maior tempo de imersão em água. CONCLUSÃO: a associação do verniz de clorexidina a um sistema adesivo utilizado em Ortodontia apresenta-se vantajosa pela sua atividade antimicrobiana.OBJECTIVE: To assess the antimicrobial activity resulting from the association of an orthodontic adhesive with chlorhexidine-thymol varnish. METHODS: Thirty-two extracted human premolars were used, divided into four groups. In Group 1, the control group, the adhesive used to bond the bracket was not associated with any antimicrobial agent. Groups 2, 3 and 4 were bonded with an adhesive system associated with chlorhexidine-thymol varnish. Groups 3 and 4 were stored in water for 7 days and 30 days, respectively, while the specimens from group 2 were, soon after bonding, placed on agar seeded with Streptococcus mutans for 48 hours, at 37º C. RESULTS: The experimental groups, with the exception of the control group, showed antimicrobial activity whose action tended to decline commensurately with the amount of time that they remained immersed in water. CONCLUSIONS: The association of chlorhexidine-thymol varnish with an adhesive system used in

  18. Effect of Surface Pretreatment on Adhesive Properties of Aluminum Alloys

    Jinsheng ZHANG; Xuhui ZHAO; Yu ZUO; Jinping XIONG; Xiaofeng ZHANG

    2008-01-01

    The lap-shear strength and durability of adhesive bonded AI alloy joints with different pretreatments were studied by the lap-shear test and wedge test. The results indicate that the maximum lap-shear strength and durability of the bonding joints pretreated by different processes are influenced by the grade of abrasive papers and can be obviously improved by phosphoric acid anodizing. Alkali etching can obviously improve the durability of bonding joints although it slightly influences the maximum lap-shear strength. The process which is composed of grit-finishing, acetone degreasing, alkali etching and phosphoric acid anodizing, provides a better adhesive bonding property of AI alloy.

  19. Advanced adhesives in electronics

    Bailey, C

    2011-01-01

    Adhesives are widely used in the manufacture of electronic devices to act as passive and active components. Recently there has been considerable interest in the use of conductive adhesives. This book reviews key types of conductive adhesives, processing methods, properties and the way they can be modelled as well as potential applications.$bAdhesives for electronic applications serve important functional and structural purposes in electronic components and packaging, and have developed significantly over the last few decades. Advanced adhesives in electronics reviews recent developments in adhesive joining technology, processing and properties. The book opens with an introduction to adhesive joining technology for electronics. Part one goes on to cover different types of adhesive used in electronic systems, including thermally conductive adhesives, isotropic and anisotropic conductive adhesives and underfill adhesives for flip-chip applications. Part two focuses on the properties and processing of electronic ...

  20. Four-year clinical evaluation of Class II nano-hybrid resin composite restorations bonded with a one-step self-etch and a two-step etch-and-rinse adhesive

    van Dijken, Jan W V; Pallesen, Ulla

    2011-01-01

    The objective of this prospective clinical trial was to evaluate the 4-year clinical performance of an ormocer-based nano-hybrid resin composite (Ceram X; Dentsply/DeTrey) in Class II restorations placed with a one-step self-etch (Xeno III; Dentsply/DeTrey) and two-step etch-and-rinse adhesive...

  1. Mechanics of Cellular Adhesion to Artificial Artery Templates

    Knöner, Gregor; Rolfe, Barbara E.; Campbell, Julie H.; Parkin, Simon J.; Heckenberg, Norman R.; Rubinsztein-Dunlop, Halina

    2006-01-01

    We are using polymer templates to grow artificial artery grafts in vivo for the replacement of diseased blood vessels. We have previously shown that adhesion of macrophages to the template starts the graft formation. We present a study of the mechanics of macrophage adhesion to these templates on a single cell and single bond level with optical tweezers. For whole cells, in vitro cell adhesion densities decreased significantly from polymer templates polyethylene to silicone to Tygon (167, 135...

  2. Surface pretreatments for medical application of adhesion

    Weber Michael

    2003-09-01

    Full Text Available Abstract Medical implants and prostheses (artificial hips, tendono- and ligament plasties usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m. This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

  3. Improved Dental Adhesive Formulations Based on Reactive Nanogel Additives

    Morães, R.R.; Garcia, J.W.; Wilson, N. D.; Lewis, S.H.; Barros, M.D.; Yang, B.; Pfeifer, C.S.; Stansbury, J.W.

    2012-01-01

    Current challenges in adhesive dentistry include over-hydrophilic bonding formulations, which facilitate water percolation through the hybrid layer and result in unreliable bonded interfaces. This study introduces nanogel-modified adhesives as a way to control the material’s hydrophobic character without changing the basic monomer formulation (keeping water-chasing capacity and operatory techniques unaltered). Nanogel additives of varied hydrophobicity were synthesized in solution, rendering ...

  4. Micromorphological characterization of adhesive interface of sound dentin and total-etch and self-etch adhesives

    Drobac Milan

    2015-01-01

    Full Text Available Introduction. The ultimate goal in restorative dentistry has always been to achieve strong and permanent bond between the dental tissues and filling materials. It is not easy to achieve this task because the bonding process is different for enamel and dentin - dentin is more humid and more organic than enamel. It is moisture and organic nature of dentin that make this hard tissue very complex to achieve adhesive bond. One of the first and most widely used tools for examining the adhesive bond between hard dental tissues and composite restorative materials is scanning electron microscopy. The aim of this study was scanning electron microscopy analyzes the interfacial micro morphology of total-etch and self-etch adhesives. Material and Methods. Micro morphological characteristics of interface between totaletch adhesive (Prime & Bond NT in combination with the corresponding composite (Ceram X Mono were compared with those of self-etching adhesive (AdheSE One in combination with the corresponding composite (Tetric EvoCeram. The specimens were observed under 1000 x magnification of scanning electron microscopy (JEOL, JSM-6460 Low Vacuum. Measurement of the thickness of the hybrid layer of the examined composite systems was performed with the software of the device used (NIH Image Аnalyser. Results. Micromorphological analysis of interface showed that the hybrid layer in sound dentin was well formed, its average thickness being 2.68 μm, with a large number of resin tags and a large amount of lateral branches for specimens with a composite system Prime & Bond NT - Ceram X Mono. However, the specimens with composite systems Adhese One - Tetric EvoCeram did not show the presence of hybrid layer and the resin tags were poorly represented. Conclusion. The results of this study suggest that total-etch adhesives bond better with sound dentin than self-etch adhesives. [Projekat Ministarstva nauke Republike Srbije, br. 174005

  5. Shear bond strength of seventh generation bonding agents on dentin of primary teeth--an in vitro study.

    Gonzalez, Geoffrey; Rich, Alfred P; Finkelman, Matthew D; Defuria, Catherine

    2012-01-01

    This controlled, randomized, in vitro study evaluated the shear bond strength of several seventh generation bonding agents on the dentin of primary teeth. Six different adhesives were used: Xeno IV, Clearfil S3 Bond, Adper Prompt-L-Pop, AdheSE One, Bond Force, and Optibond (control). Ninety primary teeth were prepared by wet grinding with a 320-grit silicon carbide paper on a polishing wheel running at 110 RPM. After 24 hours of storage in water, shear bond strengths of each group were determined. The mean shear bond strength of the tested adhesive systems to primary dentin was 12.27 MPa. One-way ANOVA testing showed a statistically significant difference between adhesive products (P < 0.001). Tukey HSD post hoc tests were used to assess which means were significantly different from one another. There was no statistically significant difference between the fifth generation adhesive system (Optibond) and the two seventh generation systems (Xeno IV and Bond Force), with Optibond exhibiting a lower mean shear bond strength compared to Bond Force. Within the limitations of this study, there is a significant difference between seventh generation bonding materials. Bond Force and Optibond appear to exhibit higher shear bond strengths than the other products. PMID:22313979

  6. Microleakage comparison of three types of adhesive systems versus GIC-based adhesive in class V composite restorations

    Mostafa Sadeghi

    2016-01-01

    Background and aims: New dentin bonding agents and techniques have been developed to reduce microleakage and create higher bond strength. This in-vitro study compared the microleakage of three resin-based adhesives versus a GIC-based adhesive on class V composite restorations.  Materials and Methods: Class V cavities were prepared on the buccal surfaces of 72 sound premolars, randomly assigned to six groups (n=12) and treated as follows: without any treatment (negative control group); total-e...

  7. Adhesion in microelectronics

    Mittal, K L

    2014-01-01

    This comprehensive book will provide both fundamental and applied aspects of adhesion pertaining to microelectronics in a single and easily accessible source. Among the topics to be covered include; Various theories or mechanisms of adhesionSurface (physical or chemical) characterization of materials as it pertains to adhesionSurface cleaning as it pertains to adhesionWays to improve adhesionUnraveling of interfacial interactions using an array of pertinent techniquesCharacterization of interfaces / interphasesPolymer-polymer adhesionMetal-polymer adhesion  (metallized polymers)Polymer adhesi

  8. Comparative quantitative and qualitative assessment of the marginal adaptation and apposition of bonded amalgam restorations using luting glass ionomer and 4-META adhesive liner under a scanning electron microscope. An in vitro study.

    Abraham M; Sudeep P; Bhat K

    1999-01-01

    The present invitro study was conducted to assess the marginal adaptation and apposition of amalgam restorations bonded to tooth structure, using freshly mixed luting glass ionomer cement (type 1) and compared with the much documented material--Amalgam bond (4-META). Twelve freshly extracted human premolar teeth were used and class V cavities were prepared on the buccal and lingual surfaces of twelve teeth for the experimental groups. Buccal cavities (class V) were prepared on twelve other te...

  9. Dentin-bonding agents

    João Carlos Gomes

    2008-01-01

    Full Text Available New dental restorative materials have been developed to meet not only the functional demands, but esthetics as well, and in the last few years an enormous range of new materials has appeared for use in dentistry. Among them, several adhesive systems, and different operative techniques for each group materials. Therefore, is indispensable for the professional to know about the properties, characteristics, and association of these materials with the dental structures, in order to select and use them correctly. Should conventional self-etching adhesive systems be used? This question encouraged this literature review to be conducted, with the aim of comparing the conventional adhesive systems with the self-etching systems and to look for scientific data that would help professionals to choose which adhesive system to use. When compared to conventional systems, it was noted that the self-etching systems show less sensitivity to technique, especially as regards errors the operator could commit. The self-etching systems, particularly the 2-step type, have shown equivalent values of bond strength, marginal microleakage and performance, therefore, will be an option for direct composite resin restorations in posterior teeth.

  10. Characterization of dentine to assess bond strength of dental composites

    Saad Liaqat; Anas Aljabo; Muhammad Adnan Khan; Hesham Ben Nuba; Laurent Bozec; Paul Ashley; Anne Young

    2015-01-01

    This study was performed to develop alternating dentine adhesion models that could help in the evaluation of a self-bonding dental composite. For this purpose dentine from human and ivory was characterized chemically and microscopically before and after acid etching using Raman and SEM. Mechanical properties of dentine were determined using 3 point bend test. Composite bonding to dentine, with and without use of acid pre-treatment and/or the adhesive, were assessed using a shear bond test. F...

  11. Adhesion Properties between Polyvinyl Acetate Dispersion and Ammonia Modified Oak Wood

    Darius MINELGA

    2013-05-01

    Full Text Available It is known that PVA dispersion exhibits very good adhesion with natural wood. However, still remains unclear what adhesion-related changes occur, when the outside factor, i. e. ammonia, affects bonding or what the stability of bonding strength is, when the moisture content of ammonia modified wood increases. The aim of this work was to assess adhesive properties of ammonia modified oak wood and the bonding strength of PVA adhesive and modified wood, and to evaluate suitability and boundaries of PVA adhesive for bonding ammonia modified wood. To explore phenomena of adhesive interface of polyvinyl acetate (PVA dispersion and modified wood ammonia treated oak was bonded using PVA dispersions manufactured by JSC “Achema”. Non-water resistant “Lipalas D2” and “Lipalas D3” with enhanced water resistance adhesives comparison allowed examining and comparing gluing performance at variable pH and ammonia content in PVA. In addition bonding strength between PVA adhesive and modified oak wood was evaluated and compared with the adhesive bondline properties for unmodified oak wood. Tests performed in accordance with the standard EN 205:2003 revealed remarkably contrasting effects at dry and wet gluing conditions especially for modified oak. The scanning electron microscope (SEM enabled image confirmation and explanation changes in the PVA adhesive interfaces after contact with modified and untreated oak wood.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4433

  12. Adhesive thickness effects of a ductile adhesive by optical measurement techniques

    Campilho, Raul; Moura, D.C.; Banea, Mariana D.; Silva, L. F. M. da

    2015-01-01

    Adhesive bonding is an excellent alternative to traditional joining techniques such as welding, mechanical fastening or riveting. However, there are many factors that have to be accounted for during joint design to accurately predict the joint strength. One of these is the adhesive layer thickness (tA). Most of the results are for epoxy structural adhesives, tailored to perform best with small values of tA, and these show that the lap joint strength decreases with increase of tA (the optimum ...

  13. Preparation of starch-g-polyacrylamide and its utilization as an adhesive for wood, paper and glass

    Starch- based adhesives are capable of wetting polar surfaces such as cellulose, penetrating pores, and forming strong bonds through mechanical and physical bonds. This paper studies the modification of starch by grafting with acrylamide, and the relation between modification and adhesion properties. Six formulae are prepared from modified and unmodified starch, and evaluated as adhesives for wood, glass, carton, and paper. Study of the factors affecting the adhesive bond is performed. Promising results are obtained. The adhesive formulae I-VI can be used successfully as paper and carton adhesives. Formulae I, TI and III can be used as wood adhesives. Excellent value for shear strength using formula No. I, comparable with other known thermoplastic and thermoset adhesives., formula I also can be used as glass adhesive, but in narrow applications and in absence of water

  14. Tensile bond strength of self-etching versus total-etching adhesive systems under different dentinal substrate conditions Resistência de união à tração de sistemas adesivos autocondicionantes versus de condicionamento total, em diferentes condições de substrato dentinário

    Alexandre Henrique Susin

    2007-03-01

    Full Text Available The use of acid etchants to produce surface demineralization and collagen network exposure, allowing adhesive monomers interdiffusion and consequently the formation of a hybrid layer, has been considered the most efficient mechanism of dentin bonding. The aim of this study was to compare the tensile bond strength to dentin of three adhesive systems, two self-etching ones (Clearfil SE Bond - CSEB and One Up Bond F - OUBF and one total-etching one (Single Bond - SB, under three dentinal substrate conditions (wet, dry and re-wet. Ninety human, freshly extracted third molars were sectioned at the occlusal surface to remove enamel and to form a flat dentin wall. The specimens were restored with composite resin (Filtek Z250 and submitted to tensile bond strength testing (TBS in an MTS 810. The data were submitted to two-way ANOVA and Tukey's test (p = 0.05. Wet dentin presented the highest TBS values for SB and CSEB. Dry dentin and re-wet produced significantly lower TBS values when using SB. OUBF was not affected by the different conditions of the dentin substrate, producing similar TBS values regardless of the surface pretreatments.O uso de condicionadores ácidos para desmineralizar a superfície dental e expor a rede de fibras colágenas para interdifusão dos monômeros adesivos e conseqüente formação da camada híbrida tem sido considerado o mais eficiente mecanismo de adesão dos agentes de união. O objetivo deste estudo foi comparar a resistência de união à dentina de três sistemas adesivos, dois autocondicionantes (Clearfil SE Bond - CSEB e One Up Bond F - OUBF e um de condicionamento total (Single Bond - SB, sob três diferentes condições de substrato dentinário (úmido, seco e reidratado. Noventa terceiros molares humanos recém-extraídos foram cortados na superfície oclusal, para se remover o esmalte e formar uma parede plana de dentina. Os espécimes foram restaurados com resina composta (Filtek Z250 e submetidos ao teste de

  15. Aspects of solvents in dentine bonding

    Ekambaram, Manikandan

    2015-01-01

    Degradation starts at the resin-dentine bonded interfaces within a few months’ of bonding. There are two major causes of degradation of the bonded interfaces over time. The simplified dental adhesives that are routinely used in the contemporary clinical dental practice are extremely hydrophilic and are prone to water sorption, leading to hydrolytic degradation. Dentine matrix-bound metalloproteinases (MMPs) and cysteine cathepsins (CCs) are proteolytic enzymes that have been shown to degrade ...

  16. A new adhesive technique for internal fixation in midfacial surgery

    Riediger Dieter

    2008-05-01

    Full Text Available Abstract Background The current surgical therapy of midfacial fractures involves internal fixation in which bone fragments are fixed in their anatomical positions with osteosynthesis plates and corresponding screws until bone healing is complete. This often causes new fractures to fragile bones while drilling pilot holes or trying to insert screws. The adhesive fixation of osteosynthesis plates using PMMA bone cement could offer a viable alternative for fixing the plates without screws. In order to achieve the adhesive bonding of bone cement to cortical bone in the viscerocranium, an amphiphilic bone bonding agent was created, analogous to the dentin bonding agents currently on the market. Methods The adhesive bonding strengths were measured using tension tests. For this, metal plates with 2.0 mm diameter screw holes were cemented with PMMA bone cement to cortical bovine bone samples from the femur diaphysis. The bone was conditioned with an amphiphilic bone bonding agent prior to cementing. The samples were stored for 1 to 42 days at 37 degrees C, either moist or completely submerged in an isotonic NaCl-solution, and then subjected to the tension tests. Results Without the bone bonding agent, the bonding strength was close to zero (0.2 MPa. Primary stability with bone bonding agent is considered to be at ca. 8 MPa. Moist storage over 42 days resulted in decreased adhesion forces of ca. 6 MPa. Wet storage resulted in relatively constant bonding strengths of ca. 8 MPa. Conclusion A new amphiphilic bone bonding agent was developed, which builds an optimizied interlayer between the hydrophilic bone surface and the hydrophobic PMMA bone cement and thus leads to adhesive bonding between them. Our in vitro investigations demonstrated the adhesive bonding of PMMA bone cement to cortical bone, which was also stable against hydrolysis. The newly developed adhesive fixing technique could be applied clinically when the fixation of osteosynthesis plates

  17. Clinical Effect of Dental Adhesive on Marginal Integrity in Class I And Class II Resin-Composite Restorations

    Manchorova-Veleva Neshka A.; Vladimirov Stoyan B.; Keskinova Donka А.

    2016-01-01

    BACKGROUND: Dental adhesives are believed to influence marginal adaptation and marginal discoloration when used under posterior resin-based composite restorations. Studies on the latest adhesive systems reveal that the group of the three-step etch-and-rinse adhesive (3-E&RA) and the one-step self-etch adhesive (1-SEA) have entirely different bonding mechanisms, as well as different bond strength and resistance to chemical, thermal and mechanical factors. STUDY OBJECTIVES: A hypothesis that a ...

  18. Adhesive joint and composites modeling in SIERRA.

    Ohashi, Yuki; Brown, Arthur A.; Hammerand, Daniel Carl; Adolf, Douglas Brian; Chambers, Robert S.; Foulk, James W., III (.,; )

    2005-11-01

    Polymers and fiber-reinforced polymer matrix composites play an important role in many Defense Program applications. Recently an advanced nonlinear viscoelastic model for polymers has been developed and incorporated into ADAGIO, Sandia's SIERRA-based quasi-static analysis code. Standard linear elastic shell and continuum models for fiber-reinforced polymer-matrix composites have also been added to ADAGIO. This report details the use of these models for advanced adhesive joint and composites simulations carried out as part of an Advanced Simulation and Computing Advanced Deployment (ASC AD) project. More specifically, the thermo-mechanical response of an adhesive joint when loaded during repeated thermal cycling is simulated, the response of some composite rings under internal pressurization is calculated, and the performance of a composite container subjected to internal pressurization, thermal loading, and distributed mechanical loading is determined. Finally, general comparisons between the continuum and shell element approaches for modeling composites using ADAGIO are given.

  19. Effect of enamel protective agents on shear bond strength of orthodontic brackets

    Montasser, Mona A; Taha, Mahasen

    2014-01-01

    Background This paper aimed to study the effect of two enamel protective agents on the shear bond strength (SBS) of orthodontic brackets bonded with conventional and self-etching primer (SEP) adhesive systems. Methods The two protective agents used were resin infiltrate (ICON) and Clinpro; the two adhesive systems used were self-etching primer system (Transbond Plus Self Etching Primer + Transbond XT adhesive) and a conventional adhesive system (37% phosphoric acid etch + Transbond XT primer ...

  20. The Valence Bond Interpretation of Molecular Geometry.

    Smith, Derek W.

    1980-01-01

    Presents ways in which the valence bond (VB) theory describes the bonding and geometry of molecules, following directly from earlier principles laid down by Pauling and others. Two other theories (molecular orbital approach and valence shell electron pair repulsion) are discussed and compared to VB. (CS)