• The Journal of Advanced Prosthodontics
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• v.9 no.2
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• pp.85-92
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• 2017

PURPOSE. The aim of this study was to evaluate the effect of tooth surface pre-treatment steps on shear bond strength, which is essential for understanding the adhesive cementation process. MATERIALS AND METHODS. Shear bond strengths of different cements with various tooth surface treatments (none, etching, priming, or etching and priming) on enamel and dentin of human teeth were measured using the Swiss shear test design. Three adhesives (Permaflo DC, Panavia F 2.0, and Panavia V5) and one self-adhesive cement (Panavia SA plus) were included in this study. The interface of the cement and the tooth surface with the different pre-treatments was analyzed using SEM. pH values of the cements and primers were measured. RESULTS. The highest bond strength values for all cements were achieved with etching and primer on enamel ($25.6{\pm}5.3-32.3{\pm}10.4MPa$). On dentin, etching and priming produced the highest bond strength values for all cements ($8.6{\pm}2.9-11.7{\pm}3.5MPa$) except for Panavia V5, which achieved significantly higher bond strengths when pre-treated with primer only ($15.3{\pm}4.1MPa$). Shear bond strength values were correlated with the micro-retentive surface topography of enamel and the tag length on dentin except for Panavia V5, which revealed the highest bond strength with primer application only without etching, resulting in short but sturdy tags. CONCLUSION. The highest bond strength can be achieved for Panavia F 2.0, Permaflo DC, and Panavia SA plus when the tooth substrate is previously etched and the respective primer is applied. The new cement Panavia V5 displayed low technique-sensitivity and attained significantly higher adhesion of all tested cements to dentin when only primer was applied.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.2
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• pp.181-190
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• 1993

The purpose of this study was to evaluate the effect of shear bond strength between various percentage of reused dental ceramic alloys and porcelain. One hundred specimens were made of one semiprecious alloy and three nonprecious alloys. Each alloy group was subdevided into five groups according to the additional precentage of new alloy. Group I specimens were made of 100% new alloy and served as the control of the investigation. Group II specimens were made of once-cast alloy with 75% new alloy. Group III specimens were made of once-cast alloy with 50% new alloy. Group IV specimens were made of once-cast alloy with 25% new alloy. Group V specimens were made of 100% recast alloy. Five specimens were made for each group of the alloy combinations. The test specimens were prepared by firing porcelain doughnuts on the alloy rod surface, and invested in dental stone. Bond strengths were measured by Instron universal testing machine at a crosshead speed of 0.5mm/min. The fractured surface of metal specimens were examined under the scanning electron microscope. The obtained results were as follows : 1. The shear bond strength of Albabond showed no significant difference between control group and reused alloy group. 2. The shear bond strength of reused alloy groups of nonprecious alloys were lower than that of control groups. 3. The shear bond strength between porcelain and metal in semiprecious alloy was higher than in nonprecious alloys 4. In nonprecious alloys. Rexillium III showed the highest bond strength value and Excelalloy showed the lowest shear bond strength value. 5. Regardless of the type of alloys and additional proportion of new alloys, scanning electron microscope photographs of the fracture surface between alloy and porcelain revealed simillar semiprecious alloy and nonprecious alloys.

• Restorative Dentistry and Endodontics
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• v.25 no.4
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• pp.550-560
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• 2000

In this study, shear bond strength of two bonding systems were measured and appearance of dentin surfaces were observed with SEM according to the storage time of eugenol on dentin surface, thus evaluated the effect of eugenol on bond strength of two dentin bonding systems. Control groups were directly bonded to dentin surface with One Step, Prime & Bond 2.1. Experimental groups were divided into experimental I and II according to dentin bonding agents. After eugenol application, dentin surfaces were bonded with One Step and Prime & Bond 2.1 according to the each storage time of immediately, 3min, 24hour, 48hour and 1week, and then control and experimental groups were filled with light cured composite resin(Z-100). After 24 hours water storage at $37^{\circ}C$, all samples were subjected to a shear load to fracture at a cross head 1.0mm/min with Instron universal testing machine(No. 4467). Etched dentin surface storaged for each time of immediately, 3min, 24hour, 48hour and 1 week after eugenol application were observed under Scanning Electron Microscope(Hitachi S-2300) at 20kvp. The data were evaluated statistically with two-way ANOVA and Tukey's HSD. The results were as follows; 1. Shear bond strengths were higher in control groups than in the experimental groups. 2. As storage time was increased after eugenol application, the shear bond strengths were decreased in experimental groups. 3. In experimental I, II the shear bond strengths were the lowest in which storage time was 1 week after eugenol application. 4. As storage time was increased after eugenol application, etched dentin surfaces showed obstructed dentinal tubule.

• Restorative Dentistry and Endodontics
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• v.29 no.4
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• pp.339-345
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• 2004

The aim of this study was to measure and compare the micro shear bond strengths of the following dentin bonding systems to the dentin surfaces under simulated pulpal pressure: All Bond $2^{\circledR},{\;}Second^{\circledR},{\;}AdheSE^{\circledR}$, Adper Prompt $L-Pop^{\circledR}$. The occlusal surfaces of 180 extracted human molars were prepared so the dentin bonding surfaces could be exposed. The teeth were randomly assigned to 3 equal groups of 60 each and subdivided. The dentin surfaces were treated with the above mentioned bonding system and resin composite cylinders were built up under a simulated pulpal pressure when saline (Group II) or diluted bovine serum (Group III) was used as the pulpal fluid. As a control. the same procedures were performed in the dried dentin surfaces (Group I). After one day of storage in water. the micro shear bond strengths were measured using an EZ tester. Group II and III showed significantly lower shear bond strength than Group I statistically (p < 0.05). $SEbond^{\circledR}{\;}and{\;}AdheSE^{\circledR}$ showed no difference among the different dentin condition. In the Adper Prompt $L-Pop^{\circledR}$. a simulated pulpal pressure were applied to the specimens using diluted bovine serum. which showed a higher strength than the specimens in which saline was used (p < 0.05).

• Journal of Technologic Dentistry
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• v.29 no.2
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• pp.141-150
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• 2007

The purpose of this study was to ascertain the bonding durability of self-etching dentin bonding agents to dentin by means of shear bonding strength. Several acid-etching dentin bonding system (ESPE Z100) and self-etching dentin bonding systems (DEN-FIL, GRADIA DIRET) were used. The occlusion surface of human molars were ground flat to expose dentin and treated with the etch bonding system according to manufactures instruction and followed by composite resin application. After 24hours of storage at 37$^{\circ}C$, the shear bonding strength of the specimens was measured in a universal testing machine with a 1mm/min crosshead speed. An one-way analysis of variance and the scheffe test were performed to identify significant differences (p<0.05). The bonded interfacial surfaces and treated dentin surfaces were examined using a SEM. Through the analysis of shear bond strength data and micro-structures of dentin-resin interfaces, following results are obtained. In dentin group, the shear bond strength of DEN-FIL showed statistical superiority in comparison to the other groups and followed by ESPE Z100 and GRADIA DIRECT (p<0.05).

• Journal of Technologic Dentistry
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• v.41 no.2
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• pp.71-80
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• 2019

Purpose: In this study, to evaluate the effect of oxide changes on the shear bond strength according to the composition of Ni-Cr alloys for porcelain fused matal crown, T-4 alloys, Zeroy alloys and Zeroy-X alloys were selected. Methods: 20 specimens were fabricated using selected Ni-Cr alloys and porcelain powders. A Ni-Cr alloy having a diameter of 5 mm and a height of 25 mm was produced and the metal surface was polished. Porcelain powder was fired on the polished metal surface to a diameter of 5 mm and a height of 3 mm. The experiment group consisted of three groups, T-4(TNA), Zeroy(ZNA) and Zeroy-X(ZXA). The fabricated specimens were mounted on a jig of a universal testing machine(UTM) and fracture strength was measured by applying a shear force at a UTM crosshead speed of 0.5 mm/min. The fracture strength was calculated as the bond strength between the porcelain and the alloy. The surface of the fractured alloy was analyzed by X-ray diffraction(XRD) and scanning electron microscopy(SEM), and the components of the oxide were measured by energy dispersive X-ray spectroscopy(EDX) line profile method. Results: In SEM, XRD and EDX analysis, yttrium tended to increase the mechanical and chemical bonding forces. The shear bond strength of ZXA group containing yttrium showed the highest value at 27.53 MPa. Conclusion: Based on the results of this study, it is considered that the yttrium-added Ni-Cr alloy is clinically acceptable in porcelain shear bond strength.

• The Journal of Advanced Prosthodontics
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• v.9 no.6
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• pp.447-452
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• 2017

PURPOSE. To evaluate the sealing performance of Hybrid Coat and its influence on the shear bond strength of five dentin surface cements. MATERIALS AND METHODS. Six premolars were pretreated to expose the dentin surface prior to the application of Hybrid Coat. The microscopic characteristics of the dentinal surfaces were examined with scanning electron microscopy (SEM). Then, 40 premolars were sectioned longitudinally, and 80 semi-sections were divided into a control group (untreated) and a study group (treated by Hybrid Coat). Alloy restoration was bonded to the teeth specimen using five different cements. Shear bond strength was measured by the universal testing machine. The fracture patterns and the adhesive interface were observed using a stereomicroscope. RESULTS. SEM revealed that the lumens of dentinal tubules were completely occluded by Hybrid Coat. The Hybrid Coat significantly improved the shear bond strength of resin-modified glass ionomer cement (RMGIC) and resin cement (RC) but weakened the performance of zinc phosphate cement (ZPC), zinc polycarboxylate cement (ZPCC) and glass ionomer cement (GIC). CONCLUSION. Hybrid Coat is an effective dentinal tubule sealant, and therefore its combined use with resin or resin-modified glass ionomer cements can be applied for the prostheses attachment purpose.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.147-163
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• 1990

Although dental porcelain demonstrates lasting esthetic results, it suffers from inherent brittle fractures. Various techniques and materials for intraoral porcelain repair has been suggested. This study investigated the in vitro shear strength of three porcelain repair systems according to aspects of the porcelain fractures. The purpose of this study was to evaluate the shear bond strength of three porcelain repair systems(All-bond, Clearfil, Scotchprime) according to fractured surface of porcelain - fused - to - metal restorations. For this study specimens were divided into five groups : group 1 represented fracture occurred at body porcelain layer, group 2 represented fracture occurred at opaque porcelain layer, group 3 represented fracture including 1/3 of metal exposure, group 4 represented fracture including 2/3 of metal exposure, and group 5 represented all metal surface was exposed. Specimens were stored in double deionized water(24Hr, $37^{\circ}C$) and thermocycling was performed(24Hr, 1080cycles), and subjected to a shear force parallel to the repair resin and porcelain interface by use of an University Testing Machine. The results of this study were obtained as follows : 1. In group 1 and 2, bond strength was relatively high, and bond strength showing reducing tendency as exposure of metal was increased. 2. In group 1, bond strength was relatively high, and no significant differences in porcelain repair system. 3. In group 2, 3 and 4, All-bond and Clearfil provided significantly higher bond strength than scotchprime. 4. In group 5, bond strength was the lowest among all groups and especially in case if Scotchprime. 5. Cohesive failure was observed in group 1 and 2, adhesive failure was observed in group 5, and cohesive / adhesive failures were observed in group 3 and 4.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.689-698
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• 1998

The purpose of this study was to evaluate the shear bond strength of light cured glass ionomer cement to enamel surface which treated with $37\%$ phosphoric acid, $10\%$ polyacrylic acid, $1.23\%$ acidulated phosphate fluoride gel and no etching agent. To compare the shear bond strength of glass ionomer cement, light-cured composite resin and chemically-cured composite resin were empoloyed as controls. Eight experiments groups were composed. 10 specimens of each group were bonded by metal bracket by tested in universal testing machine for shear bond strength, in stereoscope for adhesive remnants index. The data were evaluated statistically by SPSS/PC+. The results were as follows. 1. Among the groups of $37\%$ phosphoric acid treated and dry and bonded with light cured glass ionomer, light cured composite resin, and chemically cured composite resin, the shear bond strength of glass ionomer group showed no significant difference to the others, but the shear bond strength of chemically cured resin showed statistically lower than that of light cured resin (p<0.05). 2. The shear bond strengths of glass ionomer cement to enamel treated group with $1.23\%$ acidulated phosphate fluoride gel and $10\%$ polyacrylic acid and $37\%$ phosphoric acid showed statistically higher than that of no etched enamel group(p<0.U). 3. In the groups of glass ionomer cement, the presence of moisture was not significantly effect to the shear bond strength (p<0.05). 4. After debonding, no etched enamel group showed less residual materials on the enamel surface than the group of enamel etched with $37\%$ Phosphoric acid.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.4
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• pp.335-343
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• 2002

This study investigated the effect of temporary cement and desensitizer on the bond strength of luting cements. Total 96 dentin specimens were divided into two groups with and without temporary cementation. For temporary cement-tread group, specimens were cemented with $Temp-bond^{(R)}$ and all specimens were stored in distilled water at $37^{\circ}C$ for 7 days. Each cup was further divided into 3 subgroups with $Gluma^{(R)},\;One-step^{(R)}$ application and without desensitizer After desensitizer application, Ni-Cr specimens were luted to dentin surface with $Panavia-F^{(R)}$ and $Vitremer^{(R)}$ Specimens were placed in distilled water at $37^{\circ}C$ for 24 hours and shear bond strength between metal and dentin was measured by a universal testing machine. The results were as follows : 1. In $Panavia-F^{(R)}$ cemented groups, the combination of $One-step^{(R)}$ without temporary cement showed the greatest strength. Among the desensitizer types, $One-step^{(R)}$ showed the highest bond strength, followed by No-desensitizer, $Gluma^{(R)}$. 2. In $Vitremer^{(R)}$ cemented groups, the combination of no temporary cement and without desensitizer showed the greatest bond strength. Among the desensitizer types, No-desensitizer group showed the highest bond strength. 3. The use of $Gluma^{(R)}$ significantly reduced the shear bond strength in $Panavia-F^{(R)}$ and $Vitremer^{(R)}$ groups. 4. All temporary cement-treated groups showed a significant lower shear bond strength than without temporary cement groups. 5. Desensitizer application significantly influenced the bond strength of the resin cement and resin modified glass ionomer cement.