Adhesive Technology Research Articles

Protection and Reinforcement of Tooth Structures by Dental Coating Materials

It has been proposed that a resin coating can serve as a means to protect dental structure after preparation of the tooth for indirect restorations, sealing the exposed dentin. The resin coating is applied on the cut surfaces immediately after tooth preparation and before making an impression by assembling a dentin bonding system and a flowable composite. Resin coatings minimize pulp irritation and improve the bond strength between a resin cement and tooth when bonding the restoration to tooth. Recently, thin-film coating dental materials based on all-in-one adhesive technology were introduced for resin coating of indirect restorations. The thin coating materials are applied in a single clinical step and create a barrier-like film layer on the prepared dentin. The thin coatings play an important role in protecting the dentin from physical, chemical, and biological irritation. In addition, these thin-film coating materials reportedly prevent marginal leakage beneath inlays or crown restorations. In light of the many benefits provided by such a protective layer, these all-in-one adhesive materials may therefore also have the potential to cover exposed root dentin surfaces and prevent caries formation. In this paper, recent progress of the dental coating materials and their clinical applications are reviewed.

Ultramicroscopic study of the interface and sealing ability of four root canal obturation methods: Resilon versus gutta‐percha

Recently, filling materials have been introduced based on the dentine adhesion technologies used in conservative dentistry in an attempt to seal the root canal more effectively. The purpose of this study was to investigate the interface between the canal and root-filling material. Sealing ability of four root canal obturation methods was analysed by means of scanning electron microscopy. Extracted single-rooted teeth were endodontically treated and filled with gutta-percha/Pulp Canal Sealer using the Thermafil (TH) technique, gutta-percha/Pulp Canal Sealer using the System B (SB) technique, Resilon points/RealSeal (RS) and RealSeal 1/RealSeal (RS1). Specimen interfaces were analysed using field-emission scanning electron microscopy. The adhesive groups RS and RS1, formed hybrid layers but showed areas of separation (gaps) similar to those in the conventional obturation groups. The RS and RS1 groups showed less separation in the coronal third, but the separation was similar to that in the TH and SB groups in the middle and apical thirds. The sealing ability of Resilon is not superior to that of existing materials.

Influence of iron carbide filler in carbon matrix on the adhesive properties of acrylic pressure-sensitive adhesives

Inorganic fillers can improve coating properties, such as scratch resistance and UV stability and can significantly enhance the fillers usability in coatings and realize new market opportunities. In the pressure-sensitive adhesive (PSA) technology the inorganic fillers are used to change the very important properties of pressure-sensitive adhesives, such as tack, peel adhesion and shear strength. In the current study, the above mentioned properties of synthesized acrylic PSA using iron carbide filler in carbon matrix were investigated. The acrylic PSA containing iron carbide filler (Fe3C,C) was examined with SEM/EDX technique and the PSA adhesive and cohesive properties were examined by using a special strength machine according to AFERA tests. The conclusion is that the application of this kind of fillers allows the manufacturing of self-adhesive materials with moderate adhesiveness and very good removability.

Moulds design for adhesive bulk and joint specimens manufacturing

PurposeThe purpose of this paper is to provide an insight into the techniques which are used and developed for adhesive bulk and joint specimens manufacturing.Design/methodology/approachAfter a short introduction, the paper discusses various techniques for adhesive bulk and joint specimens manufacturing and highlights their advantages and limitations. A number of examples in the form of different bulk and joint specimens of different types of adhesives are used to show the methods for determining the adhesive's mechanical properties needed for design in adhesive technology. In order to predict the adhesive joint strength, the stress distribution and a suitable failure criterion are essential. If a continuum mechanics approach is used, the availability of the stress‐strain curve of the adhesive is sufficient (the bulk tensile test or the TAST test is used). For fracture mechanics‐based design, mode I and mode II toughness is needed (DCB and ENF tests are used). Finally, single lap joints (SLJs) are used to assess the adhesive's performance in a joint.FindingsBefore an adhesive can be specified for an application, screening tests should be conducted in order to compare and evaluate the various adhesion parameters. Properties of adhesives can vary greatly and an appropriate selection is essential for a proper joint design. Thus, to determine the stresses and strains in adhesive joints in a variety of configurations, it is necessary to characterize the adhesive behaviour in order to know its mechanical properties. A great variety of test geometries and specimens are used to obtain adhesive properties. However, for manufacturing of adhesive bulk specimens and joints necessary for use in these tests, properly, moulds should be designed.Originality/valueThe paper summarises the main methods of preparing adhesive bulk and joint specimens and the test methods for determining the mechanical properties needed for design in adhesive technology. Emphasis is given to the preparation of specimens of suitable quality for mechanical property determination and the moulds designed for this purpose.

Chemical analyses in dental adhesive technology

Summary Adhesive technology has evolved rapidly since it was introduced more than fifty years ago. Today, decayed or fractured teeth can be reconstructed minimally invasively and nearly invisibly using adhesive technology. However, the clinical longevity is sometimes still too short. Although water sorption is thought to be the main destabilizer of the biomaterial–tooth bond, the actual interfacial degradation mechanisms are far from understood. The fundamental mechanism of bonding to enamel and dentin is essentially based on an exchange process, in which minerals removed from the dental hard tissues are replaced by resin monomers that upon polymerization become micro-mechanically interlocked in the created porosities. In addition to micro-mechanical interlocking through hybridization, the potential benefit of additional chemical interaction between functional monomers/polymers and tooth substrate components has recently regained attention. In this review paper, we focus on how chemical interaction at the biomaterial–hard tissue interface can improve bond durability.

Adhesive technology – Key to future of lightweight design?

Adhesive technology – Key to future of lightweight design?

Characteristics and Application of the Novel Synthetic Material AWPP for Water Purification

Through the hot pressing compound adhesive technology of synthesis of the Novel Synthetic Materials "Artificial Water-Purifying Plant" (AWPP) which is made of polyester fiber non-woven fabrics and Cross-linked polyethylene bubble. Material production process, principle and characteristics of AWPP are introduced in the article. From the different concentration of water purification contrast test, analysis of the material in ascension water purification system processing power play a role. The results indicate that AWPP have technologies advantages of qualitative light, corrosion resistance, buoyancy, more specific surface area, microbial attachment than large amount, form quickly microbial membrane and so on. To different concentrations of water quality of different pollutants index, it can effectively improve water purification effect 18%-40%, and use of low cost, market broad prospect of application.

Polyurethane structural adhesives applied in automotive composite joints

In recent years structural adhesives technology has demonstrated great potential for application due to its capacity to transform complex structures into solid unitary and monolithic assemblies using different materials. Thus, seams or joints integrate these structures providing, besides a reduction in weight, a considerable increase in the mechanical resistance and stiffness. The increase in the industrial use of structural adhesives is mainly due to their ability to efficiently bond different materials in an irreversible manner, even replacing systems involving mechanical joints. In the automobile industry structural adhesives have been widely used for the bonding of metal substrates, thermoplastics and composites, frequently employing these in combination, particularly glass fiber and polyester resin composites molded using RTM and SMC processes. However, the use of urethane structural adhesives in applications involving composites and thermoplastics has been the subject of few investigations. In this study the effects of temperature and time on the shear strength of RTM, SMC and ABS joints, applying temperatures of -40, 25, 80, 120 and 177 °C and times of 20 minutes and 500 hours, were determined. The objective was to evaluate the performance under extreme conditions of use in order to assess whether these joints could be used in passenger or off-road vehicles. The results showed that the urethane structural adhesive promoted the efficient bonding of these materials, considering that due to the high adhesive strength the failures occurred in the substrates without adversely affecting the bonded area. For each test condition the joint failure modes were also determined.

Contemporary management of tooth replacement in the traumatized dentition

Dental trauma can result in tooth loss despite best efforts at retaining and maintaining compromised teeth (Dent Traumatol, 24, 2008, 379). Upper anterior teeth are more likely to suffer from trauma, and their loss can result in significant aesthetic and functional problems that can be difficult to manage (Endod Dent Traumatol, 9, 1993, 61; Int Dent J 59, 2009, 127). Indeed, teeth of poor prognosis may not only present with compromised structure but trauma may also result in damage to the support tissues. Injury to the periodontium and alveolus can have repercussions on subsequent restorative procedures (Fig. 19). Where teeth are identified as having a hopeless prognosis either soon after the incident or at delayed presentation; planning for eventual tooth loss and replacement can begin at the early stages. With advances in both adhesive and osseointegration technologies, there are now a variety of options for the restoration of edentate spaces subsequent to dental trauma. This review aims to identify key challenges in the provision of tooth replacement in the traumatized dentition and outline contemporary methods in treatment delivery.

Fast Curing of Adhesives in the Field of CFRP

The interest in carbon fiber reinforced plastic (CFRP) structures does not only increase in the area of aircraft construction, but also in the automotive industry. Due to the two-dimensional load transfer adhesive technology offers a particularly high potential of joining structures in lightweight construction. The adhesive systems applied for joining relevant CFRP structures show an insufficient initial strength thus necessitating additional fixing of the components or an accelerated curing of the adhesive. Induction technology has proved to be the most adequate heating technique for fast curing of metal bonds since it achieves high heating rates and enables a drastic reduction of the curing times. Due to their electrical conductivity, CFRP can also be heated by induction. Well-founded studies have been published explaining the physical mechanism behind the generation of heat within CFRP by electromagnetic induction. However, the relation between material and process parameters and the resulting heat generation and temperature distribution in CFRP parts still need to be investigated since, contradictory statements can be found in the literature. A profound knowledge of these relations, though, is elementary in order to predict the heat generation which is necessary to design a safe, fast curing process and to avoid damages to the material. Thus, the fundamental relations existing between the material/process parameters, the heat generation, and the resulting joining characteristics will be verified and discussed.

New devices for very long-term ECG monitoring

Present day 24-h Holter monitors have been shown to miss many arrhythmias that may occur infrequently or under specific circumstances. The advancement in electronic and adhesive technologies have enabled the development of first generation wearable long-term 14-day patch ECG monitors that attach directly to the skin and require no electrodes and wires to operate. This new technology is unobtrusive to the patients and offers them unprecedented mobility. It enables very long-term monitoring of critical patients while they are carrying out daily activities. The monitors are waterproof, offer good adhesion to the skin and can operate as either recorders or wireless streaming devices.

Indirect Resin Onlay Cemented with Self-adhesive Resin Cement: A Comprehensive Clinical Overview

ABSTRACT Advances in adhesive technology and esthetic dental materials have permitted clinicians to perform conservative preparation of the dentition for onlay restorations. Indirect resin onlays are a great alternative to dental crowns for reestablishment the function and esthetic in teeth with great destruction. Key messages Indirect resin onlay is economical solution to satisfy the function and esthetic requirements of these patients. The cementation with self-adhesive resin cement is practice, fast and reduces the postoperative sensitivity. How to cite this article Bandéca MC, Tonetto MR, Barros ÉD, Pinto SCS, Firoozmand LM, de Andrade MF, Cury Saad JR, Maia Filho EM, de Sousa Queiroz RC. Indirect Resin Onlay Cemented with Self-adhesive Resin Cement: A Comprehensive Clinical Overview. World J Dent 2012;3(3):273-277.

Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners.

The advent of the esthetic era and advances in adhesive technology saw the emergence of resin composite materials. But the problem of polymerization shrinkage remained. This was due to the contraction of the resin during curing inducing internal and interfacial stresses at the tooth restoration interface, leading to gap formation and subsequent micro-leakage. A number of techniques and modifications in the material have been proposed to minimize polymerization shrinkage and microleakage. In this study, the hypothesis that the placement of resin-modified glass ionomer cement (RMGIC) or flowable composite, as liner, beneath the packable composite, on the gingival surface of the tooth [coronal or apical to cementoenamel junction (CEJ)], could reduce the microleakage in class II composite restorations, was tested. Sixty recently extracted noncarious human mandibular molars were used. The teeth were randomly divided into three groups (20 specimens each): Group I (Filtek P60 with RMGIC liner), group II (Filtek P60 with Filtek Z350 liner) and Group III (Filtek P60 without liner). The teeth of each group were further subdivided into two subgroups (equal number of cavities). Subgroup A gingival seat 1 mm occlusal to CEJ on mesial side. Subgroup B gingival seat 1 mm apical to CEJ on distal side. It was concluded that in class II composite restorations gingival microleakage is more at the dentinal surface than on enamel. The use of a flowable composite and RMGIC, as liners, beneath the packable composite, in class II composite restorations, significantly reduces the microleakage when margins are in dentin, but the reverse is true, when the margins are in enamel.How to cite this article: Arora R, Kapur R, Sibal N, Juneja S. Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners. Int J Clin Pediatr Dent 2012;5(3):178-184.

Switchable adhesion by chemical functionality and topography

Progress in adhesion technology over the last few decades has led to widespread replacement of mechanical fasteners with adhesive bonds. Despite the advances, it remains challenging to produce materials that are sticky on demand. In this feature article we highlight recent efforts to develop reversibly switchable adhesives, that exhibit the ability to trigger adhesion in response to an environmental change – for example, pH, solvent, temperature, mechanics, and electro/magnetic field. We review two initially separate design principles to induce switchable adhesion: (1) chemical functionality and (2) topography. Combining both approaches may lead to novel hierarchical adhesives with interesting property profiles.

I 材料技術 3. 新素材（高分子）「最新の接着剤と接着技術の動向」

I 材料技術 3. 新素材（高分子）「最新の接着剤と接着技術の動向」

薄膜の密着性の科学と技術

薄膜の密着性の科学と技術

Understanding adhesives for filter fabrication

Up and down the production line at filter manufacturing plants, adhesives are mixed, extruded and coated onto components. Given the vital role of adhesives in filter assembly, filter manufacturers want to know more about them. Hugh Evans of Franklin Adhesives & Polymers provides some basic information to aid understanding and selection of the right adhesive technologies for specific bonding applications in filter manufacturing plants.

液晶ポリマーの接着技術とその応用

液晶ポリマーの接着技術とその応用

Kinetic Monte Carlo Simulation of the Adsorption Competition of Epoxide Components on the Aluminium Oxide Surface

In the present work we describe a kinetic Monte-Carlo method (KMC) in the framework of the lattice gas model for the simulation of the adsorption in multicomponent systems from a liquid solution. The algorithm is subsequently used for an investigation of the influence of an adhesion promoter additive on the adsorption of amine-curing epoxide components on the aluminium oxide surface. The KMC method is coupled to the Metropolis algorithms to accelerate the simulations and take into account effects of various adsorption sites and neighboring adsorbates. An inclusion of the bulk diffusion in the simulation scheme allows to study the distribution of components in the solution near the interface. Parameters used in the simulations are reaction barriers and reaction energies for the surface complex formation. They were calculated in previous works by using density functional based tight binding (1–3). Results of the simulations show that the small additions of the adhesion promoter (˜2%), which adsorption is more favourable in comparison to other components, lead to the essential increasing of surface concentration of adsorbed molecules and as a consequence to the increasing of the adhesive strength. The analysis of simulated adsorption kinetics allows us to evaluate the engineering rules, which can be useful in the optimisation of the adhesive technology.

Wood coupled with adhesive technology instead of steel or concrete

Wood coupled with adhesive technology instead of steel or concrete