• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.4
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• pp.419-426
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• 2017

Attachment of the orthodontic bracket conducted during the window opening procedure can result in failure due to various adverse conditions such as blood or saliva contamination, or other wet conditions. For the success of the bracket attachment, reduction of total operation time is crucial. The purpose of this literature is to evaluate the differences between the final resultant shear bond strength of the conventional method of using phosphoric acid and self-etching primer, and that of the operation time-reduced method in which the curing step is omitted subsequent to the primer application. A total of 40 human maxillary incisors were prepared. Group I(control group) and II were etched with 37% phosphoric acid and Group III and IV were conditioned with self-etching primer. Attachment of the group I and III was conducted by manufacturer's instructions. The operation time of Group II and IV was reduced by eliminating the curing step after the primer application. The resultant shear bond strength of each group was measured and an adhesive remnant index (ARI) was recorded. The mean shear bond strength of group I, II, III, and IV were 14.16 MPa, 8.33 MPa, 8.29 MPa, and 6.48 MPa respectively. Significant differences could only be found between the control group and the experimental groups (p < 0.05). The ARI indicated no significant difference among all groups.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.60-67
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• 2015

In order to evaluate the bond performance of domestic larch glulam and the glass fiber reinforced plastic (GFRP) rod, the specimen with the GFRP rod bonded-in domestic larch glulam for pull-out test was produced. The test was carried out using various specimens with different gluing depth, width of glue-line and type of adhesive. The cantilever type rahmen structure specimen with bonded-in GFRP rods was produced based on the result of pull-out test, and its moment resistance performance was compared and examined with the moment resistance performance of slotted-in steel plate specimen. As a result of the pull-out test, the most excellent bond performance was found when the insertion depth of GFRP rods was 5 times larger than the diameter of GFRP rods. When the glue-line thickness was 1 mm, the bond performance improved by 17%~29% in comparison to the bond performance in the case of the glue-line thickness of 2 mm. Also, the bonded strength of the specimen used with poly-urethane adhesive was 2.9~4.0 times greater than the bonded strength of specimen used with resorcinol adhesive. The cantilever type rahmen structure specimen with bonded-in GFRP rods showed the moment resistance performance 0.82 times lower in comparison to the slotted-in steel plate specimen used with the drift pin, but the initial stiffness was similar as 0.93 times.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.5
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• pp.144-152
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• 2010

In this study, cement-based filler is used as an adhesive instead of organic adhesive, epoxy because there were problems under wet condition. First, the bond strength of cement-based filler was measured and the result was satisfied with KS F 4716. However, in case of wet condition, bond strength of epoxy adhesive decreased $0.73N/mm^2$ in 7 days and $0.84N/mm^2$ in 14 days from pilot test. This implies that there would be a problem on reinforced concrete structure in wet condition, such as tunnel and sewage box. In the second experiment, the flexural strength of RC beams with GFRP using different thickness of cement-based filler was investigated, and the result was indicated 113%, 66%, 75% increase in 10mm, 20mm, 30mm thickness, respectively. From the result, it was known that 10mm filler thickness produces stable bond performance.

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.233-244
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• 1996

The purpose of this study was to compare the shear bond strength obtained from ceramic and plastic brackets bonded with various light-cured adhesives and to evaluate their debonded failure sites. Plastic brackets, Transcend 6000, Signature and Starflre TMB brackets were bonded with Orthobond, Light Bond and Transbond on one hundred forty extracted human premolar teeth as manufacturer's descriptions. After thermocycling the brackets were debonded with an Instron universal testing machine and the debonded bracket base surfaces were inspected under stereoscope to evaluate the failure sites. Also the shear bond strength and failure patterns with different curing time and with two different source of light were compared. The results were as follows. 1. There were no statistically significant differences among the mean shear bond strength of Orthobond, Light Bond and Transbond in a same bracket group except Plastic bracket group(p<0.05). 2. The mean shear bond strength of each adhesive with different bracket groups showed statistically significant differences. Stafire TMB showed the highest shear bond strenght among the brackets in this study, but there was no statistically singnificant difference with Transcend 6000 while there was statistically significant difference with Signature.(p<0.05) 3. The various bonding failure patterns were occurred among different bracket groups but most of failure sites were bracket base -adhesive interfaces. 4. There were no statistically significant differences in shear bond strength between the groups with curing time of 10 second and 20 second, and between the groups with two different sources of light as long as sufficient light intensity(above $400mWcm^2$) were provided(p<0.05). According to the result, it should be considered in clinical use of ceramic bracket with light-cured adhesives that the shear strengths of ceramic brackets were influenced by the retention from of bracket base as well as the composition of bracket and there was no difference in the shear bond strenght among various light-cured adhesives used in this study.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.373-378
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• 2002

The waterproofing system's performance is known to show a determining by complex interaction of material factors, design details, and the qualify of construction, and the waterproofing integrity of waterproofing membranes is determined by the bond to the deck and the amount of damage to the waterproofing membrane. In this research, the basic properties of waterproofing membranes on market and the tensile adhesive characteristics of waterproofing systems of concrete bridge deck have also been investigated in the view of the damages frequently reported from job site. As a results of tensile adhesive strength of waterproofing system, tensile strength is decrease with surface moisture contents except for inorganic-elastomeric liquid waterproofing membrane, and increase with strength of deck slab. Also tensile adhesive strength is generally increase in case of moisture curing of specimen because of pore structure and surface leveling. The after asphalt concrete paving tends to increase more than before those. The results of the liquid waterproofing membranes are upside-down, and the more concrete has strength, the more strength of tensile adhesive increase. The ambient temperature and the rolling temperature of asphalt concrete when application of the waterproofing membrane has considerable influence on the performance of waterproofing system.

• Journal of Adhesion and Interface
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• v.4 no.2
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• pp.21-29
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• 2003

Hot AC anodising has been evaluated us pre-treatment for aluminium prior to structural adhesive bonding. Phosphoric and sulphuric acid hot AC anodising showed very promising adhesion promoter capabilities with durability comparable with the best standard DC anodising procedures. AC anodising does not required etching prior to anodising and offers u pre-treatment time down to 20 seconds. The interface/interphase between the aluminium substrate and the adhesive was investigated in order to get a better understanding of the involved adhesion mechanisms and to explain the long-tenn properties. The alkaline medium formed at the oxide layer/adhesive interface has been shown to induce a partial dissolution of the oxide layer leading to the formation of metallic ions which diffuse in the adhesive (EPMA measurements). The effect of diffusion of the Al ions on adhesion and joint durability is still uncertain but studies showed that pre-bond moisture affected the joints durability and to some extent the diffusion length. specially for DC anodised samples. So far no direct correlation could be established between the diffusion length d and the joints durability but new trials with better control over the elapsed time between bonding and adhesive curing are expected to help getting a better understanding of the involved mechanisms.

• International Journal of Highway Engineering
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• v.16 no.4
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• pp.21-33
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• 2014

PURPOSES: The purpose of this study was to break away from the workforce method using cold-mix asphalt mixtures and has a constant quality and has develop repair materials of pre-production asphalt-precast types. METHODS: The selection of the repair material was determined as the results obtained through physical properties of materials and the field applicability. In case of repair materials, values obtained through Marshall stability test & the dynamic stability test & retained stability test as well as the site conditions was considered. In case of adhesive, test results were obtained through examination of the bond strength(tensile, shear) and the field applicability of the adhesive was examined through combined specimens to simulate field applications. RESULTS : According to the results of laboratory tests, in the case of repair materials, Marshall stability and dynamic stability, retained stability of cold-mix reaction type asphalt mixture is the highest. In the case of adhesive, two-component epoxy-urea has a very high bonding strength(tensile, shear) was most excellent. According to the results of field tests, when epoxy-urea was excellent workability. Also, the repair body through actual mock-up test did not occur large deformation and fracture after 12 months. CONCLUSIONS : A suitable repair material is cold-mix reaction type mixture of asphalt-precast, a suitable adhesive is a two-component epoxy-urea.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.2
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• pp.123-132
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• 2000

The field of maxillofacial prosthetics is concerned with the prosthetic reconstruction of missing head and neck tissue. Currently, facial prostheses are usually applied in cases of defects caused by the surgical removal of tumors or congenital defects. While silicone has been most widely used for the reconstruction of missing maxillofacial defects, it does not have ideal physical properties. Therefore, bonding a thin polyurethane sheet to silicone prostheses was recommended. In this case skin adhesives were used for the retention of maxillofacial prostheses. But retention of devices has always been problematic. The contributions of implants can be made to solve these problems. Implants have reduced the need for adhesive use, simplifying cleaning procedures and thus extending the life of the prostheses. For implant-retained prostheses, retentive matrix is necessary to hold attachments and/or magnets. The retentive matrix is usually fabricated with autopolymerizing acrylic resin or visible light- polymerized resin. The purpose of this study was to compare the adhesion-in-peel force of silicone adhesive to autopolymerizing acrylic resin and polyurethane sheet with two different surface textures : pumice polish only or retention groove, and three surface primers : Dow corning 1205 primer or Dow corning S-2260 primer or FactorII A-304 primer, and two polymerization methods : room temperature or dry heat oven. The t-peel bond strength of specimens was determined as described in ASTM Standard D1876-72. The results were statistically analyzed using the ANOVA test, multiple range test and t-test The results were as follows. 1. The t-peel bond strength of A-304 primer was the highest and statistically higher than that of S-2260(p<0.05). 2. The t-peel bond strength of specimens with retention groove was statistically higher than that of specimens polished with pumice(p<0.05). 3. The t-peel bond strength of specimens polymerized in dry heat oven was statistically higher than that of specimens in room temperature(p<0.01).

• Restorative Dentistry and Endodontics
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• v.28 no.5
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• pp.392-401
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• 2003

The purpose of this study was to evaluate the penetration pattern of dentin adhesives according to the orientation of dentinal tubules with confocal laser scanning microscopy. Specimens having perpendicular. parallel and oblique surface to dentinal tubules were fabricated. The primer of dentin adhesives (ALL $BOND^{\circledR}{\;}2,{\;}CLEARFIL^{TM}$ SE BOND and PQ1) was mixed with fluorescent material. rhodamine B isothio-cyanate (Aldrich Cherm. CO., Milw., USA), It was applied to the specimens according to the instructions of manufactures. The specimens were covered with composite resin (Estelite, shade A2) and then cut to a thickness of 500$\mu\textrm{m}$ with low speed saw (Isomet^{TM}, Buehler. USA). The adhesive pattern of dentin adhesives were observed by fluorescence image using confocal laser scanning microscopy. The results were as follows. 1. For the groups with tubules perpendicular to bonded surface. funnel shape of resin tag was observed in all specimen. However. resin tags were more prominent in phosphoric acid etching system (ALL $BOND^{\circledR}$ 2 and PQ1) than self etching system ($CLEARFIL^{TM}$ SE BOND). 2. For the groups with tubules parallel to bonded surface. rhodamine-labeled primer penetrated into peritubular dentin parallel to the orientation of dentinal tubules. But rhodamine-labeled primer of PQ1 diffused more radially into surrounding intertubular dentin than other dentin adhesive systems. 3. For the groups with tubules oblique to bonded surface. resin tags appeared irregular and discontinuous. But they penetrated deeper into dentinal tubules than other groups.

• Restorative Dentistry and Endodontics
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• v.41 no.2
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• pp.83-90
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• 2016

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 etchand-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 (${\alpha}=0.05$). 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.