• 대한치과교정학회지
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• 제48권3호
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• pp.163-171
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• 2018

Objective: The aim of this study was to evaluate the mechanical and biological properties of orthodontic bonding agents containing silver- or zinc-doped bioactive glass (BAG) and determine the antibacterial and remineralization effects of these agents. Methods: BAG was synthesized using the alkali-mediated solgel method. Orthodontic bonding agents containing BAG were prepared by mixing BAG with flowable resin. $Transbond^{TM}$ XT (TXT) and $Charmfil^{TM}$ Flow (CF) were used as controls. Ion release, cytotoxicity, antibacterial properties, the shear bond strength, and the adhesive remnant index were evaluated. To assess the remineralization properties of BAG, micro-computed tomography was performed after pH cycling. Results: The BAG-containing bonding agents showed no noticeable cytotoxicity and suppressed bacterial growth. When these bonding agents were used, demineralization after pH cycling began approximately 200 to $300{\mu}m$ away from the bracket. On the other hand, when CF and TXT were used, all surfaces that were not covered by the adhesive were demineralized after pH cycling. Conclusions: Our findings suggest that orthodontic bonding agents containing silver- or zinc-doped BAG have stronger antibacterial and remineralization effects compared with conventional orthodontic adhesives; thus, they are suitable for use in orthodontic practice.

• 소음진동
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• 제8권6호
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• pp.1093-1102
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• 1998

The success of controllability of smart structures depends on the quality of the bonding along the interface between the main structure and the attached sensing and acuating elements. Generally, the analysis procedures neglect the effect of the interfacial bond layer or assume that this bond layer behaves like viscoelastic material. Three different bond layers. two modified epoxy adhesives, and one isocyanate adhesive were prepared for their toughness and moduli. Bond layer of the chosen adhesive provides an almost perfect bonding condition between the composite structure and the PZT while bended significantly like arrow-shape. The perfect bonding condition is tested by considering various material properties of the bond layers. and based on this perfect bonding condition, the effects of the interfacial bond layer on the dynamic behavior and controllability of the test structure is experimentally studied. Once the perfect bonding condition is achieved. dynamic effects of the bond layer itself on the dynamic characteristics of the main structure is negligible. but the contribution of the attached PZT elements on the stiffness of the multi-layered structure becomes significant when the thickness of the bond layer increased.

• 대한치과교정학회지
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• 제42권1호
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• pp.32-38
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• 2012

Objective: The aim of this study was to compare the effects of different enamel conditioning techniques for bracket bonding. Methods: Ninety-one human premolars were randomly divided in six groups of 15 specimens each. The enamel surfaces of the teeth were etched with 35% orthophosphoric acid in Group 1, with a self-etching primer in Group 2, sandblasted in Group 3, sandblasted and etched with 35% orthophosphoric acid in Group 4, conditioned by Er:YAG laser in Group 5 and conditioned by Er:YAG laser and etched with 35% phosphoric acid gel respectively in Group 6. After enamel conditioning procedures, brackets were bonded and shear bonding test was performed. After debonding, adhesive remnant index scores were calculated for all groups. One tooth from each group were inspected by scanning electron microscope for evaluating the enamel surface characteristics. Results: The laser and acid etched group showed the highest mean shear bond strength (SBS) value ($13.61{\pm}1.14$ MPa) while sandblasted group yielded the lowest value ($3.12{\pm}0.61$ MPa). Conclusions: Although the SBS values were higher, the teeth in laser conditioned groups were highly damaged. Therefore, acid etching and self-etching techniques were found to be safer for orthodontic bracket bonding. Sandblasting method was found to generate inadequate bonding strength.

• 접착 및 계면
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• 제3권1호
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• pp.37-42
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• 2002

Adhesives are becoming increasingly accepted for advanced engineering/boding tasks. Therefore the understanding of the basic principles and the benefits of elastic bonding and structural bonding respectively is of utmost importance. Structural bonding means adhesive performance in load-bearing environments. Furthermore. the time to achieve handling strength has an impact on the economics of an assembly line. The paper gives briefly a summary about the fundamentals of elastic bonding and discusses different adhesive systems in the context of handling strength. Hereby the focus lies on the Warm Melt Technology, and its potential is compared to standard adhesives (l-part, 2-part and Booster Technology, a special 2-C system). Examples illustrate their economical benefits. Main Points : ${\bullet}$ The basic principles and benefits of elastic bonding ${\bullet}$ Warm-melt Technology in comparison with standard adhesives ${\bullet}$ Handling strength an economic issue ${\bullet}$ Combination with Booster-Technology, a special 2-C PUR system ${\bullet}$ Presentation of real world applications Learning Objectives: ${\bullet}$ Fundamentals of elastic bonding ${\bullet}$ Warm-melt Technology: correlation between chain length and cristallinity ${\bullet}$ Handling strength and curing speed of various systems in comparison ${\bullet}$ Real world applications illustrate the potential of the Warm-melt Technology.

• Restorative Dentistry and Endodontics
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• 제28권3호
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• pp.209-221
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• 2003

The objectiveness of this study was to evaluate whether low-viscosity composite can bond effectively to dentin surface without bonding resin. The low-viscosity composites being 50wt% filler content were made by the inclusion of bonding resin of two self-etching systems(Cleafil SE Bond, Unifil Bond) varied with contents as 0, 10, 20, 30, 40, 50wt%. Exposed dentin surfaces of extracted 3rd molars are used. Dentin bond strengths were measured. The tests were carried out with a micro-shear device placed testing machine at a CHS of 1mm/min after a low-viscosity composite was filled into an iris cut from micro tygon tubing with internal diameter approximately 0.8mm and height of 1.0mm. 1 Flexural strength and modulus was increased with the addition of bonding resin. 2. Micro-shear bond strength to dentin was improved according to content of bonding resin irrespective of applying or not bonding resin in bonding procedure, and that of Clearfil SE Bond groups was higher than Unifil Bond. 3. There were no significant difference whether use of each bonding resin in bonding procedure for S-40, S-50, U-50(p＞0.05). 4. In SEM examination, resin was well infiltrated into dentin after primed with self-etching primer only for S-50 and U-50 in spite of the formation of thinner hybrid layer. Low viscosity composite including some functional monomer may be used as dentin bonding resin without an intermediary bonding agent. It makes a simplified bonding procedure and foresees the possibility of self-adhesive restorative material.

• 대한소아치과학회지
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• 제49권3호
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• pp.264-273
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• 2022

치과에서 사용하는 재료들의 물성의 발달로 인하여 브라켓과 치아 사이의 결합 능력도 크게 향상되었다. 그러나 소아치과 영역에서와 같이 환자의 협조를 기대하기 어렵거나, 수분 격리가 제대로 이루어지지 않을 경우 기대하는 효과에 미치지 못하는 결합강도를 보여 줄 수 있다. 본 연구의 목적은 세 가지의 접착 술식을 비교하여 브라켓의 전단 접착 강도를 평가하고, 임상적으로 유의한 차이가 존재하는지 비교하는 것이다. 우식증이나 수복물이 없는 상, 하악 소구치 60개 치아를 대상으로 하였다. Group I은 대조군으로서 기존의 3 step 접착 방식에 따라 브라켓을 부착하였고, Group II는 self-etching primer system을 이용하여 부착하였다. Group III는 self-priming adhesive를 이용하여 브라켓을 부착하였다. 각 group의 전단 결합 강도를 측정하고 접착제 잔류지수(ARI)를 기록하였다. 각 group I, II, III의 평균 전단 결합 강도는 14.69 MPa, 11.21 MPa 그리고 12.21 MPa로 측정되었다. Group I과 II, group I과 III에서만 유의한 차이가 존재하였으며(p < 0.05), ARI 값은 모든 group에서 유의한 차이가 존재하지 않았다.

• Elastomers and Composites
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• 제28권4호
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• pp.274-282
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• 1993

Resorcinol-tannin-formaldehyde-latex(RTFL) adhesive was prepared to bond SBR to nylon in reinforced rubber composites. A key factor of adhesive contributes to the adhesion strength between SBR and nylon was the toughness of adhesive itself. Although the stiffness and strength of adhesive film decreased slightly with increasing level of tannin substitution for resorcinol in a standard RFL adhesive, the maximum toughness of adhesive film, which showed yield behavior and high dissipative capacity, was obtain by 60% tannin substitution. However, a marked softening and reduction in toughness occurred at sufficiently high substitution. Also, the adhesive film, which was heat-treated to simulate cure, showed higher strength than the unheated film. Thus, the properties of tannin containing adhesives could be optimized by using 40/60 weight ratio of the resorcinol/tannin in RTFL adhesive composition as well as heat treatment of adhesive film.

• 농업과학연구
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• 제37권2호
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• pp.267-270
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• 2010

This study was carried out to manufacture black charcoal board from domestic wood waste by using serum protein adhesive which is natural, environment-friendly and human-friendly. For the preparation of the serum protein adhesive, pig blood from slaughterhouse was centrifuged and serum was separated from corpuscles and concentrated to 30% by dry weight basis. The particle size of charcoal from domestic wood waste for this study was #6-60. Hot pressing schedule was $170^{\circ}C$ and 40kgf/$cm^2$ (1 min)-10kgf/$cm^2$ (2.5 min)-40kgf/$cm^2$ (5 min). The black charcoal board made by the addition of 13% serum protein adhesive on dry weight basis gave 41.76kgf/$cm^2$ of bending strength, 8.12kgf/$cm^2$ of internal bonding strength, and excellent gas adsorption and workability.

• Restorative Dentistry and Endodontics
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• 제46권3호
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• pp.32.1-32.10
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• 2021

Objectives: This study aimed to evaluate the effect of the application method of universal adhesives on the shear bond strength (SBS) of repaired composites, applied with different thicknesses. Materials and Methods: The 84 specimens (Filtek Z350 XT) were prepared, stored in distilled water for a week and thermocycled (5,000 cycles, 5℃ to 55℃). They were roughened using 400-grit sandpapers and etched with phosphoric acid. Then, specimens were equally divided into 2 groups; Single Bond Universal (SU) and Prime&Bond Universal (PB). Each group was subdivided into 3 subgroups according to application methods (n = 14); UC: 1 coat + uncuring, 1C: 1 coat + curing, 3C: 3 coats + curing. After storage of the repaired composite for 24 hours, specimens were subjected to the SBS test and the data were statistically analyzed by 2-way analysis of variance and independent t-tests. Specimens were examined with a stereomicroscope to analyze fracture mode and a scanning electron microscope to observe the interface. Results: Adhesive material was a significant factor (p = 0.001). Bond strengths with SU were higher than PB. The highest strength was obtained from the 1C group with SU. Bonding in multiple layers increased adhesive thicknesses, but there was no significant difference in SBS values (p = 0.255). Failure mode was predominantly cohesive in old composites. Conclusions: The application of an adequate bonding system plays an important role in repairing composite resin. SU showed higher SBS than PB and the additional layers increased the adhesive thickness without affecting SBS.

• 대한소아치과학회지
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• 제50권4호
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• pp.434-442
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• 2023

This study was aimed to evaluate the bonding performance of a self-adhesive giomer and compare it to a conventional flowable composite resin with regard to shear bond strength and microleakage in enamel and dentin. Healthy human premolars extracted for orthodontic treatments were used in the study. For shear bond strength tests, enamel and dentin specimens were prepared for the study group with self-adhesive giomer and for the control group with conventional flowable composite resin with a 5th-generation adhesive system. A universal testing machine was used to measure the shear bond strength. For the microleakage tests, specimens were immersed in a 2% methylene blue solution for 24 hours, cut into sections, and evaluated with a stereomicroscope for the extent of dye penetration. The results of the study showed no statistically significant difference in shear bond strength between the self-adhesive giomer and the conventional flowable composite resin in enamel (p = 0.091). On the contrary, in dentin, the self-adhesive giomer showed significantly lower shear bond strength (p < 0.0001). The microleakage of the self-adhesive giomer was significantly higher than that of the conventional flowable composite resin (p = 0.002). Self-adhesive giomer is considered useful for restoring small cavities at the enamel level of pediatric patients by reducing chair time with the advantage of a simple bonding process. However, as the study was conducted in a laboratory setting, further research in a clinical environment is deemed necessary.