• 대한치과보철학회:학술대회논문집
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• 1995.12a
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• pp.66-66
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• 1995

• Restorative Dentistry and Endodontics
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• v.30 no.3
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• pp.204-214
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• 2005

This study compared the microtensile bond strength (${\mu}$TBS) and microscopic change of two 2-step and two 1-step self-etching adhesives to dentin according to storage times in distilled water. Occlusal dentin was exposed in 48 human molars. They were divided to four groups by different adhesives: SE Bond group (Clearfil SE Bond), AdheSE group (AdheSE). Adper group (Adper Prompt L-Pop), and Xeno group (Xeno III) . Each group was stored in 37$^{\circ}C$ distilled water for 1, 15, and 30 days. Resin-bonded specimens were sectioned into beams and subjected to ${\mu}$TBS testing with a crosshead speed of 1 mm/minute. For SEM observation, one specimen was selected and sectioned in each group after each stroage time. Resin-dentin interface was observed under FE-SEM. In all storage times, mean ${\mu}$TBS of SE group was significantly higher than those of other groups (p < 0.05). There was no significant difference between mean ${\mu}$TBS of SE group and AdheSE group among all storage times, but significant difference between 1- and 30-day storage in mean y${\mu}$TBS of Adper group and Xeno group (p > 0.05). For 1-and 15-day storage, all groups showed the close adaptation between resin-dentin interfaces. For 30-day storage, resin-dentin interfaces showed wide gap in Adper group and separate pattern in Xeno III group.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.3
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• pp.212-219
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• 2015

This study focuses evaluating the efficiency and performance evaluation of composite type sheet-membrane waterproofing method that utilizes a separation behavior inducement system designed to resolve the chronic problems of disintegration and damage of overlap areas of waterproofing layers. As the result of the test, the tensile strength value was at 13.8N/mm and elongation rate at 587% for the separation behavior inducement type specimen, and the compared specimens had 14.2N/mm for tensile strength and 335% for elongation rate. For the separation behavior adhesion method specimen, when tensile stress or displacement occurred, the Zero-Span tension occurrence did not follow, which resulted in that the bottom sheet layer and the top membrane layer did not simultaneously becoming damaged. When undergoing the top and bottom layers were separated through separation behavior due to lack of flexibility, the bottom layer began to damage at the primary stage, and with the allowed boundary the upper membrane layer began to display flexibility and showed continuous displaced resulting in secondary phase damaging.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.493-502
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• 1997

This study was conducted to evaluate the tensile bond strength by bonding the dental bracket with Super-bond after treating the surface of dental Nickel-Chromium alloy with sandblasting, sandblasting & tin-plating, respectively, and tin-plating. 10 pieces of Nickel-Chromium alloys with brackets bonded with Super-bond without their surface treatment were sampled as a control group, 20 pieces of Nickel-Chromium alloy brackets bonded with Super-bond after treating them with sandblasting as group I, 20 pieces of Nickel-Chromium alloys tin-plated and bonded with Super-bond after sandblasting as group II, and then 20 pieces of alloys with brackets bonded with Super-bond after tin-plating as group III. The result of those examination and comparison is summarized as follows: 1. Group I showed the mean tensile bond strength of $14.41{\pm}2.24MPa$ which was highest among 4 groups, followed by group III($13.59{\pm}.51MPa$), group II($12.27{\pm}.45MPa$), and control group($10.50{\pm}1.57MPa$), respectively. However, it was shown that there was no statistically significant difference between group I and III, group III and II, and group II and control group(p>0.05). 2. The main failure pattern of those brackets showed that $70\%$ of the control group had an adhesive failure at the bracket-Superbond interface, and $30\%$ at the Nickel-Chromium alloy-Superbond interface, while other groups did the adhesive failure at the bracket-Superbond interface. 3. When examined under SEM, it was shown that adhesives were mostly attached to the surface of the Nickel-Chromium alloy for all groups while a considerable quantity of adhesives were attached to the bracket base. Then, those samples treated only with sandblasting showed the most even and remarkable roughness of their surface.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.106-115
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• 2010

The purpose of this study was to evaluate the microtensile bond strength (${\mu}TBS$), failure modes and bonding interfaces of self-etching and three self-adhesive resin cements to dentin and indirect composite resin. Cylindrical composite blocks (Tescera, Bisco Inc.) were luted with resin cements (PA: Panavia F 2.0, Kuraray Medical Inc., RE: RelyX Unicem Clicker, 3M ESPE., MA: Maxem, Kerr Co., BI: BisCem, Bisco Inc.) on the prepared occlusal dentin surfaces of 20 extracted molars. After storage in distilled water for 24 h, $1.0\;mm\;{\times}\;1.0\;mm$ composite-dentin beams were prepared. ${\mu}TBS$ was tested at a cross-head speed of 0.5 mm/min. Data were analyzed with one-way ANOVA and Tukey's HSD test. Dentin sides of all fractured specimens and interfaces of resin cements-dentin or resin cements-composite were examined at FESEM (Field Emission-Scanning Electron Microscope). In conclusion, PA and RE showed higher bond strength and closer adaptation than MA and BI when indirect composite blocks were luted to dentin using a self-etching and three self-adhesive resin cements.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.8-15
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• 2010

Purpose: The purpose of this study was to evaluate the effect of various methods of dentin bonding agent application and air abrasion pretreatment on microtensile bond strength between dentin and resin, using a self-etching adhesive system. Material and methods: Thirty freshly extracted human molars were obtained and divided into 6 groups of 5 teeth. A 2-step self etching adhesive system (Clearfil SE Bond) was used for all groups. The control specimens were prepared using a direct immediate bonding technique. The delayed dentin sealing specimens were prepared using an indirect approach without dentin prebonding. The immediate dentin sealing specimens were prepared using dentin prebonding immediately following preparation. Immediate dentin sealing teeth and delayed dentin sealing teeth had provisional restorations using Fermit for two weeks. Then all specimens of each group were divided into two groups of three, depending on air abrasion pretreatment. Composite "crowns" were incrementally built on and specimens were stored in water for 24 hours. All teeth were prepared for a microtensile bond strength test. Bond strength data were analyzed with a one-way ANOVA test, and post hoc comparison was done using the Scheffe's test. Results: The mean microtensile bond strengths of all groups were not statistically different from each other. Conclusion: When preparing teeth for indirect restorations, IDS and DDS with Clearfil SE bond, have no difference on the microtensile bond strength between dentin and resin. Air abrasion pretreatment did not affect the microtensile bond strength when using IDS and DDS with Clearfil SE bond.

• Magazine of the Korea Concrete Institute
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• v.10 no.5
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• pp.109-115
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• 1998

철근콘크리트 구조물이 과소설계되어 있거나 과다 하중이 작용하게 되면 그 구조물의 구조성능을 파악하여 보수.보강을 시행하게 된다. 최근에 가장 맣이 사용되는 보수.보강 재료로는 특히 휨내력을 보강하는데 탄소섬유를 들 수 있다. 탄소섬유쉬트는 내열성과 내호염성에 있어서 회재가 발생할 경우 보강재료로서 충분한 성능을 가지고 있다. 그러나 이를 접착시키는데 사용되는 에폭시는 유기계 물질로서 화재시 유독가스가 발생하고 내열성능도 30$0^{\circ}C$정도에도 지탱하기 어려워 화재 발생이 가능한 구조물에 사용하기 어렵다. 이 연구에서는 무기계 폴리머 복합재료로 접착된 탄소섬유를 고온(약 800~100$0^{\circ}C$, 1시간)으로 가열한 후 가열된 섬유판의 인장, 휨 전단내력을 검토하여 내열성능을 파악하고 이 섬유쉬트로 보강한 철근콘크리트 부재의 휨 성능을 실험적으로 규명하여 화재의 위험이 있는 구조물에 구조적인 보강재료로 사용이 가능한가를 검토하였다. 연구 결과, 개발된 무기계 폴리머 복합체는 인장강도, 휨강도 및 접착강도가 유기계 접착제와 유사하게 나타났고 800~100$0^{\circ}C$ 정도로 1시간 가열한 이후에도 상온 시험체 휨내력과 전단내력의 63%, 33% 정도를 유지하여 화재의 위험이 있는 부위에도 사용이 가능한 것으로 판단되었다.

• Composites Research
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• v.13 no.3
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• pp.58-66
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• 2000

CARALL(Carbon fiber reinforced aluminum laminates) was fabricated with CFRP prepreg and A17075, using a autoclave. The mechanical properties of three samples i.e. A17075, CFRP and CARALL were also investigated as a function of size in circular holes. Theoretical approach into analysing mechanical behaviors near the circular hole notch was carried out to compare with experimental data, furthermore. By the adhesive bonding of A17075 to CFRP, abrupt strength reduction was prevented. From the consideration of modified point stress failure criterion, predicted results was well consistent with the experimental one.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.528-537
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• 1999

The purpose of this study was to analyze and compare the bond strengths between stainless steel plate and zinc phosphate cement, polycarboxylate cement and glass ionomer cement, which are frequently used for cementation of stainless steel crowns. Three cementing materials were glued to the poles standing above stainless steel plate, bovine teeth, light cured glass ionomer restorative material and amalgam. And the tensile bond strengths between them were measured with universal testing machine and the results were statistically processed using ANOVA and Student t-test. The obtained results were as follows : 1. On stainless steel plate, glass ionomer cement and polycarboxylate cement showed higher tensile bond strengths compared to zinc phosphate cement, with no significant difference between the former two. 2. On the surface of bovine teeth and glass ionomer restorative material, glass ionomer cement showed highest bond strength, followed by polycarboxylate cement and zinc phosphate cement in order. 3. For amalgam restoration, polycarboxylate cement and glass ionomer cement showed higher tensile bond strengths than zinc phosphate cement, with no significant difference between the former two.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.11
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• pp.147-154
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• 2019

The purpose of this study is to evaluate the effect of admixtures as blast-furnace slag(BF) and fly ash(FA) on tensile and adhesive properties of polymer cement mortar(PCM) with EVA emulsion. The test specimens are prepared with five polymer-cement ratio(P/C) and five admixture contents, and tested for tensile strength and adhesion in tension. From the test results, the tensile strength and adhesion in tension could be improved by an appropriate combination of P/C and admixture contents. In particular, the maximum of tensile strength of PCM with P/C 10% and BF content of 10% is 4.70MPa which is about 1.55 times higher than that of plain mortar, and about 1.22 times that of PCM that does not contain any mixture. The ratio of adhesion in tension to tensile strength of PCM with admixtures averaged 55.8%. It is also apparent that admixture contents of 5% or 10% could be proposed for improvement of tensile strength and adhesion in tension of PCM.