• Journal of Technologic Dentistry
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• v.24 no.1
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• pp.65-71
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• 2002

This study was performed to observe the microhardness change of the surface and the bonding strength between the porcelain and alloy specimens in order to investigate the effects of appended indium, tin and copper on interfacial properties of Au-Pd-Ag alloys. The hardness of castings was measured with a micro-Vicker's hardness tester. The interfacial shear bonding strength between alloy specimen and fused porcelain was measured with a mechanical testing system(MTS 858.20). The microhardness of Au-Pd-Ag alloy was increased by adding indium and tin, but not increased by adding copper. The shear bonding strength of Au-Pd-Ag-Sn alloy and Au-Pd-Ag-Cu alloy showed 87MPa, 57MPa. The higher concentration of adding elements showed the higher shear bonding strength.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.263-271
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• 2003

The purpose of the present study was to evaluate the patterns of hybrid layer according to the application time and the frequency and its effects on the shear bonding strength of All-In-One system in primary teeth. A single bonding agent(Scotchbond Multi-Purpose Plus, 3M) and an All-In-One system(Prompt L-pop, 3M ESPE) were applied on the dentin varying the application time and the frequency in primary teeth. Shear bond strength was measured and the patterns of hybrid layers were observed by SEM. The following results were obtained ; 1. The shear bonding strength of single bonding agent was significantly higher than that of All-In-One system(P<0.05). 2. The shear bonding strength of All-In-One system applied twice or 3 times were higher than that of applied once (P<0.05). And thickness of the hybrid layer was increased when applied twice or 3 times compared to once. 3. The shear bonding strength of All-In-One system when applied for 15 second and 30 second were higher than that of 7 second (P<0.05). And the hybrid layer thickness of 15 second and 30 second's application time were higher than that of 7 second. 4. Thickness of hybrid layer applied with single bonding agent was $2-4{\mu}m$ and that of All-In-One system was $1-2{\mu}m$.

• Journal of the Korean Wood Science and Technology
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• v.16 no.3
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• pp.5-16
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• 1988

This experiment was executed to investigate the effect of activation of veneer surface by oxidizing agents, hydrogen peroxide and nitric acid, on bonding characteristics of Malas(Homalium foetidum Benth) plywood, in which the effects of these oxidizing agents amount, pretreatment time, and pressing time and temperatue on shear strength of the plywood were examined and discussed. In this research the activation of veneer surface by oxidants was effective in raising shear strength but the difference in shear strength was not observed between hydrogen peroxide and nitric acid treatment. Hydrogen peroxide treatment, however, seemed to be more profitable to industrial application because of its lower concentration and easier handling than nitric acid. The bonding method by lignin-phenol adhesive through surface activation revealed inferior shear strength to phenol- and urea-formaldehyde adhesive but superior water resistance to urea-formaldehyde adhesive and this bonding method, in addition, have the advantage of lower cost compared with phenol-formaldehyde adhesive, Therefore, this bonding method by lignin-phenol adhesive through surface activation seemed to economical in manufacturing of water-resistant wood panel materials in future.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.583-591
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• 1990

If the bond strength is sufficient to resist orthodontic force, orthodontic brackets can be bonded to restorations. Orthodontic brackets were bonded to composite resin and glass ionomer cement restorations with no-mix adhesive or glass ionomer cement. The shear bond strength of adhesives bonded to restorations was studied in vitro. Orthodontic brackets were bonded to 10 extracted natural teeth, 40 composite resin restorations and 40 glass ionomer restorations. The surfaces of composite resin restorations were roughened or applied with bonding agent (Scothbond) after surface roughening. The surfaces of glass ionomer cement restorations were conditioned with acid etching or applied with Scotchbond to etched surface. The adhesive was no-mix resin or glass ionomer cement. The shear bond strength was measured. The results were as follows: 1. Orthodontic brackets could be bonded to composite resin restorations effectively as they could be bonded to acid etched enamel with no-mix adhesive. The shear bond strength was sufficient to resist orthodontic force and was not affected by bonding agent greatly. 2. The shear bond strength of no-mix adhesive bonded to acid etched glass ionomer cement restorations was sufficient to resist orthodontic force. However. the fracture risk of glass ionomer cement restorations was increased during debonding. The bonding agent couldn't increase the shear bond strength greatly. 3. The shear bond strength of glass ionomer cement bonded to glass ionomer cement restorations was lower than that of no-mix adhesive. The shear bond strength was sufficient to resist orthodontic force and was greatly decreased by bonding agent. 4. The shear bond strength of glass ionomer cement bonded to composite resin restorations was too low to resist orthodontic force.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.2
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• pp.450-460
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• 1996

The purpose of this study was to compare shear bond strength of composite resin using several dentin bonding agents and light cured glass ionomer cement(Fuji II LC). 40 Bovine primary anterior teeth were used for this experiment. Labial surface of teeth were flattened. It were divided into four groups. Each group was composed of 10 teeth. The material used for this experiment were Scotchbond Multipurpose-Z-100, Allbond 2-Aelitefil, Gluma-Pekalux, light cured glass ionomer cement(Fuji II LC). Each of the materials was applied to the exposed surfaces of 10 teeth by insertion into a cylindrical shaped matrix which is 3mm diameter and 3mm in height. The completed specimens were stored at $37^{\circ}C$ under 100% humidity for 24 hours : the shear bond strength of each material to dentin surface were measured with INSTRON universal testing machine. The results were as follows : 1. Shear bond strength to dentin surface increased in order of light cured glass ionomer cement(Fuji II LC), Gluma, Allbond 2, Scotchbond Multipurpose. 2. Between shear bond strength of light cured glass ionomer cement(Fuji II LC) and Allbond 2, there was statistical significace(p<0.05) 3. Between shear bond strength of light cured glass ionomer cement(Fuji II LC) and Scotchbond Multipurpose, between shear bond strength of Gluma and Scotchbond Multipurpose, there was statistical significance.(p<0.01) The shear bond strength of dentin bonding agents were higher than light cured glass ionomer cement. The reason is that materials and quality of dentin bonding agent were enhanced. Further investigation is necessary to improve shear bond strength of light cured glass ionomer cement.

• The korean journal of orthodontics
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• v.22 no.2 s.37
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• pp.449-474
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• 1992

The purpose of this study was to evaluate the in vitro shear bond strengths to enamel and the failure sites of three ceramic brackets and one metal bracket in combination with light cured orthodontic adhesive. The brackets were divided into four groups. Each ceramic bracket group had different bonding mechanisms with adhesive. Group A; metal bracket with foil-mesh base (control group) Group B; ceramic bracket with micromechanical retention Group C; ceramic bracket with chemical bonding Group D; ceramic bracket with mechanical retention and chemical bonding. Forty extracted human lower first premolars were prepared for bonding and 10 brackets for each group were bonded to prepared enamel surfaces with $Transbond^{\circledR}$ light cured ortho dontic adhesive. Twenty four hours after bonding, the Instron universal testing machine was used to test the shear bond strength of brackets to enamel. After debonding, brackets and enamel surfaces were examined under stereoscopic microscope to determine the failure sites, Statistical analysis of the data was carried out with ANOVA test and $Scheff\acute{e}$ test using SPSS PC+. The results were as follows. 1 . There were statistically significant differences in mean shear bond strengths of three ceramic bracket groups (p < 0.05). Shear bond strengths of group C and D were significantly higher than that of group B and shear bond strength of group C was significantly higher than that of group D. 2. Group C and D both had significantly higher shear bond strengths than metal bracket (group A), but there were no significant differences in shear bond strengths between group A and B (p < 0.05). 3. The failure sites of four bracket groups were also different. Group C and D failed primarily at enamel-adhesive interface, but group A and B failed primarily at bracket base-adhesive interface. 4. Among all ceramic bracket groups, group B was very similar to metal bracket in the aspect of shear bond strength and failure site.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.1
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• pp.26-49
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• 1998

The purpose of this study was to confirm the formation of hybrid layer and resin tags in dentin tissue and the possibility of bonding between luting cements used for the prosthesis and the resinous surface coated with resin bonding agents to prevent the dentin hypersensitivity after abutment preparation. Some resin bonding agents, which may have the possibility of bonding with polyacrylic acid as a liquid ingredient of polycarboxylate and glass ionomer cements, were selected. All-Blond desensitizer containing NTG-GMA and BPDM, Scotch-Bond Multipurpose plus containing HEMA, and XR-bond containing organophosphate were selected as a coating agent. Dental cements were zinc phosphate, polycarboxylate, and glass ionomer cement. After the exposed dentin surface of premolars was ethced with 10% phosphoric acid and coated with resin bonding agents, the morphology of treated surfaces and the resin tags and hybrid layers on sectioned surfaces were observed by SEM. Shear bond strength between the resin bonding agents and 3 kinds of cements was measured 24 hours after bonding. On the debonded surfaces of the shear bond strength tested specimens, the cement tags and the bonding sites between the resin materials and cements were examined by SEM. Following conclusions were drawn : 1. Coating of dentin with resin bonding agents had no effect on the shear bond strength of zinc phosphate cement. 2. Both of polycarboxylate and glass ionomer cements showed the increased shear bond strength by the dentinal coating with Scotch-Bond Multipurpose plus containing HEMA. However, in the case of dentinal coating with some agents containing NTG-GMA and BPDM or organophosphate, polycarboxylate cement exhibited the lowered shear bond strength, and glass ionomer cement showed the unchanged shear bond strength. 3. Complete obstructions of dentinal tubules were observed on the dentin coated with All-Bond desensitizer or XR-bond, but distinct shape of the orifices of dentinal tubules was observed consistently on the dentin coated with Scotch-Bond Multipurpose plus. 4. The hybrid layer was thickest on the dentin coated with All-Bond desensitizer, and the length of resin tags was longest on the dentin coated with Scotch-Bond Multipurpose plus. 3. On the debonded specimens which had been bonded with polycarboxylate cement or glass ionomer cement after coating with Scotch-Bond Multipurpose plus, the cement tags and the bonding sites between the resinous surface and the cements could be examined.

• The Journal of Advanced Prosthodontics
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• v.2 no.2
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• pp.39-45
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• 2010

PURPOSE. The aim of this study was to determine differences in shear bond strength to human dentin using immediate dentin sealing (IDS) technique compared to delayed dentin sealing (DDS). MATERIALS AND METHODS. Forty extracted human molars were divided into 4 groups with 10 teeth each. The control group was light-cured after application of dentin bonding agent ($Excite^{(R)}$ DSC) and cemented with $Variolink^{(R)}$. II resin cement. IDS/SE (immediate dentin sealing, $Clearfil^{TM}$ SE Bond) and IDS/SB (immediate dentin sealing, $Adapter^{TM}$ Single Bond 2) were light-cured after application of dentin bonding agent ($Clearfil^{TM}$ SE Bond and $Adapter^{TM}$ Sing Bond 2, respectively), whereas DDS specimens were not treated with any dentin bonding agent. Specimens were cemented with $Variolink^{(R)}$. II resin cement. Dentin bonding agent ($Excite^{(R)}$. DSC) was left unpolymerized until the application of porcelain restoration. Shear strength was measured using a universal testing machine at a speed of 5 mm/min and evaluated of fracture using an optical microscope. RESULTS. The mean shear bond strengths of control group and IDS/SE group were not statistically different from another at 14.86 and 11.18 MPa. Bond strength of IDS/SE group had a significantly higher mean than DDS group (3.14 MPa) (P < .05). There were no significance in the mean shear bond strength between IDS/SB (4.11 MPa) and DDS group. Evaluation of failure patterns indicates that most failures in the control group and IDS/SE groups were mixed, whereas failures in the DDS were interfacial. CONCLUSION. When preparing teeth for indirect ceramic restoration, IDS with $Clearfil^{TM}$ SE Bond results in improved shear bond strength compared with DDS.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.85-94
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• 2013

PURPOSES: The performance of tack coat, commonly used for layer interface bonding, is affected by application rate and curing time. In this study, bonding strength tests were performed according to the application rate and curing time of asphalt emulsion. Based on finding from this study, optimum application rates and curing times are proposed. METHODS: In order to investigate bonding characteristic of asphalt emulsion, tests were performed on both asphalt concrete pavement and portland concrete pavement. Also, asphalt emulsions were tested at the application rate of 0, 0.2, 0.4, 0.6, and $0.8{\ell}/m^2$ and at the curing time of 0, 0.5, 1, 2, and 24 hours. Pull-off test and shear bonding strength test, which commonly used for bonding strength measurement of asphalt emulsion, were adopted for this study. To assess field performance under different testing condition, asphalt emulsions were applied to in-service pavement. Throughout coefficient of determination analysis between material index properties from asphalt emulsion and mechanical response from bonding strength tests, performance correlativity was analyzed. RESULTS: Test results show that optimum application rate for asphalt overlay on asphalt concrete pavement (AOA) and asphalt overlay on concrete pavement (AOC) was $0.4{\sim}0.5{\ell}/m^2$ and $0.3{\sim}0.5{\ell}/m^2$, respectively. According to the curing time increment, tensile strength and shear strength of AOC were increased to 22~44% and 20~39%, respectively. AOA case also show strength increment in tensile strength (42%) and shear strength (9%). We tested the applicability of tack coat materials at the field sites, and our findings demonstrated that the bonding (for D and E) and rapid curing (for B, C, and D, E) performances were superior than others. Among material index properties, there was a high correlation between penetration ratio and bonding strength test result. CONCLUSIONS : Result show that interlayer bonding strength was affected by asphalt emulsion type, application rate and curing time. AOC required slightly higher application ($0.1{\ell}/m^2$) than AOA. Both AOA and AOC cases show higher strength at longer curing time. Up to 2hours of curing, rapid strength increments were observed, but strength increment ratio was decreased after 2hours of curing. From the observed correlation between penetration ratio and bonding strength, it is expected that penetration ratio can be used as one of important factors affecting bonding strength analysis.

• Journal of Technologic Dentistry
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• v.35 no.2
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• pp.113-120
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• 2013

Purpose: This study was to observe surface property and bonding strength according to composition of Ni-Cr alloy for porcelain fused to metal crown. The two kinds of Ni-Cr alloy with different composition ratio of parent metal were observed general properties and chemical properties of each alloy surface and measured the shear bonding strength between ceramic and each alloys. The aim of study was to suggest the material for design of parent metal's composition ratio to development of alloy for porcelain fused to metal crown. Methods: The two kinds of alloy as test specimen was Ni(71wt.%)-Cr(12wt.%) and Ni(63wt.%)-Cr(23wt.%) alloy. The oxide on surface was observed by SEM and EDX. And the shear test was performed by MTS. Results: The surface property and oxide characteristic analysis of oxide layer, weight percentage of Element O within $Ni_{71}Cr_{12}$ alloy measured 12.74wt.%, but $Ni_{63}Cr_{23}$ alloy was measured 15.91wt.%. And the maximum shear bonding strength was measured 106.14MPa between $Ni_{71}Cr_{12}$ alloy and vintage halo (VV group). Conclusion: The surface property and oxide characteristic of $Ni_{71}Cr_{12}$ alloy was similar to $Ni_{63}Cr_{23}$ alloy. And VV group has the strongest shear bonding strength.