• 대한치과보철학회지
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• 제24권1호
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• pp.177-189
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• 1986

To investigate the bond strength of etched porcelain, porcelain specimens were etched by 5% hydrofluoric acid during the time of 2.5 min., 5 min., 7.5 min., and 10 min. at $23^{\circ}C$ and observed by SEM. Also, electrolytically etched metal was observed by SEM. Etched porcelain specimens were treated or were not treated with Silane coupling agent and bonded to etched metals with Comspan and Panavia. The bonded specimens were stored in water at $37^{\circ}C$. 24 hours after bonding, the bond strengths were measured. There were four groups of 25 specimens each. Group 1 was bonded with Panavia. Group 2 was bonded with Panavia after treated with Silane coupling agent. Group 3 was bonded with Comspan, Group 4 was bonded with Comspan after treated with Silane coupling agent. The results were as follows: 1. he etched porcelains were obviously observed by SEM. 2. The dendritic arms were observed in etched metal by SEM. 3. The bond strength in relation to the increase of etching time increased and an analysis of variance shows significantly different at the 0.01 level in all groups. 4. The bond strength of Silane coupling agent treated groups were higher than the untreated. 5. The ratios of increase of the bond strengths of Silane coupling agent treated groups in relation to the increase of etching of etching time were lower than the untreated. 6. The bond strength of the groups used Comspan were higher than Panavia.

• Restorative Dentistry and Endodontics
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• 제42권3호
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• pp.188-199
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• 2017

Objectives: This in vitro study evaluated the effect of dentin biomodifiers on the immediate and long-term bond strengths of a simplified etch and rinse adhesive to dentin. Materials and Methods: Flat coronal dentin surfaces were prepared in 120 extracted human molars. Teeth were randomly divided into 5 groups (n = 24) according to 5 different surface pre-treatments: No pre-treatment (control); 1M carbodiimide (EDC); 0.1% epigallocatechin-3-gallate (EGCG); 2% minocycline (MI); 10% sodium ascorbate (SA). After surface pre-treatment, adhesive (Adper Single Bond 2 [SB], 3M ESPE) was applied. Composite was applied into transparent plastic tubes (2.5 mm in diameter), which was placed over the bonded dentin surface. From each group, 10 samples were subjected to shear bond strength (SBS) evaluation at 24 hours (immediate) and remaining 10 samples were tested after 6 months (delayed). Additionally, 4 samples per group were subjected to scanning electron microscopic analysis for observation of resin-dentin interface. The data were statistically analysed with Shaperio-Wilk W test, 2-way analysis of variance (ANOVA), and post hoc Tukey's test. Results: At 24 hours, SBS of all surface pre-treatment groups were comparable with the control group, with significant differences found between EDC and SA groups only (p = 0.009). After 6 months storage, EDC, EGCG, and MI pre-treatments preserved the resindentin bond strength with no significant fall. Conclusions: Dentin pre-treatment with all the dentin biomodifiers except SA resulted in significant preservation of resin-dentin bond over 6 months storage period, without negatively affecting the immediate bond strength of the etch and rinse adhesive tested.

• Restorative Dentistry and Endodontics
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• 제46권4호
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• pp.53.1-53.11
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• 2021

Objectives: This study evaluates the bond strength and marginal adaptation of mineral trioxide aggregate (MTA) Repair HP and Biodentine used as apical plugs; MTA was used as reference material for comparison. Materials and Methods: A total of 30 single-rooted teeth with standardized, artificially created open apices were randomly divided into 3 groups (n = 10 per group), according to the material used to form 6-mm-thick apical plugs: group 1 (MTA Repair HP); group 2 (Biodentine); and group 3 (white MTA). Subsequently, the specimens were transversely sectioned to obtain 2 (cervical and apical) 2.5-mm-thick slices per root. Epoxy resin replicas were observed under a scanning electron microscope to measure the gap size at the material/dentin interface (the largest and smaller gaps were recorded for each replica). The bond strength of the investigated materials to dentin was determined using the push-out test. The variable bond strengths and gap sizes were evaluated independently at the apical and cervical root dentin slices. Data were analyzed using descriptive and analytic statistics. Results: The comparison between the groups regarding the variables' bond strengths and gap sizes showed no statistical difference (p > 0.05) except for a single difference in the smallest gap at the cervical root dentin slice, which was higher in group 3 than in group 1 (p < 0.05). Conclusions: The bond strength and marginal adaptation to root canal walls of MTA HP and Biodentine cement were comparable to white MTA.

• 대한치과보철학회지
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• 제31권2호
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• pp.165-179
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• 1993

Dicor has not been prescribed routinely, in spite of many advantages, because of esthetic limitations by excessive translucency and external shading. In an attempt to solve these problems, the technique of veneering Dicor by aluminous poreclain has been used and recently Dicor Plus system was developed. The purpose of this study was to evaluate the compatibility between Dicor and several veneering porcelains by measuring the shear bond strength and observing the failure mode and interface appearance with SEM. Total 55 Dicor disks(10.0mm diam. X 3.0mm thickness) were fabricated by lost wax technique and divided into five groups of 11. Veneering porcelains such as Dicor Plus, Vitadur Alpha, Vitadur N, Vivodent, and Ceramco II were built up over the center of the treated Dicor surface using paper tube(5.0mm diam. X 4.0mm height) and fired according to the manufacturesr’instructions. A representative sample from each group was completely embedded in epoxy resin and crosssectioned, and remaining 50 samples were embedded in epoxy resin with the bonded area perpendicular to table base. The shear bond strengths were measured by applying the shear load parallel to Dicor surface close to the bonded area. Failure modes and interface appearances were observed using SEM at 15 and 1000 magnification respectively. The obtained results were as follows : 1. The mean shear bond strengths showed Dicor-Dicor Plus(10.53 MPa); Dicor-Vitadur Alpha(8.84 MPa); Dicor-Vitadur N(7.37 MPa); Dicor-Vivodent(4.28 MPa); Dicor-Ceramco II(0.89 MPa). 2. The shear bond strength of Dicor-CeramcoII was significantly decreased compared with Dicor-Dicor Plus(p<0.01), but had no significant difference compared with Dicor-Vivodent(p>0.01). 3. The shear bond strengths of Dicor-Vitadur Alpha and Dicor-Vitadur N were not significantly different compared with Dicor-Dicor Plus(p>0.01). 4. SEM examination of bond failure modes revealed that Dicor-Dicor plus, Dicor-Vitadur Alpha, Dicor-Vitadur N exhibited cohesive failure within Dicor and Dicor-Vivodent exhibited adhesive failure. And Dicor-Ceramco III exhibited adhesive failure and cohesive failure within CeramcoIII together. 5. SEM examination of interfaces revealed that Dicor-Dicor Plus exhibited the most tight contact and Dicor-Vitadur Alpha, Dicor-Vitadur N exhibited acceptible contacts. But Vivodent exhibited discontinuous gap and Ceramco II exhibited large continuous gap.

• Restorative Dentistry and Endodontics
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• 제20권2호
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• pp.856-868
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• 1995

The effect of collagen dissolution in acid conditioned dentin layer on resin - dentin adhesion was investigated. 160 freshly extracted human molars were divided into 4 groups randomly and dentin surfaces were exposed. 40 exposed dentin surfaces were not acid conditioned and each 10 of them were applied with bonding agents within dentin bonding systems of All Bond 2, Scotchbond Multipurpose, Clearfil Photobond and Superbond D - Liner respectively. Each 10 of another 40 exposed dentin surfaces were acid conditioned by the acid within the above four bonding systems respectively and applied with corresponding bonding systems. After acid conditioning of the other 40 exposed dentin surfaces as above, they were treated with 5% NaOCl for 2 minutes, and each 10 of them were applied with the above four dentin bonding systems respectively. The remaining 40 dentin surfaces were acid conditioned and treated with 10% NaOCl for 2 minutes, and each 10 of them were applied with corresponding bonding agents as the above. After the procedures were finished, composite resin (Z -100, 3M Dent. Prod., USA) were applied on the dentin surfaces and light cured. Shear bond strength values were measured. Surface changes of fractured dentin specimens were observed using SEM (Hitachi S-2350, Japan). The following results were obtained. 1. In all of dentin bonding systems, shear bond strengths of non - conditioned specimens were significantly lower than those of acid conditioned specimens (P<0.05). 2. A statistically significant difference of bond strengths did not exist between acid conditioned specimens and 5% NaGCI retreated specimens applied with All Bond 2, Scotchbond Multipurpose and Clearfil Photobond (P>0.05). However, strength values of 5% NaOCl retreated specimens applied with Superbond D - Liner were lower than those of acid conditioned specimens (P<0.05). 3. In all the applied dentin bonding systems except Clearfil Photobond, bond strengths of 10% NaOCl retreated specimens were lower than those of acid conditioned and 5% NaOCl retreated specimens (P<0.05). 4. The resin - dentin hybrid layer of 4 - $5{\mu}m$ thickness was formed in the acid conditioned specimens applied with All Bond 2, Scotchbond Multipurpose and Superbond D-Liner. 5. The resin - dentin hybrid layer of 3 - $4{\mu}m$ thickness was still formed in the 5% NaOCl retreated specimens applied with All Bond 2 and Scotchbond Multipurpose. In addition, this layer was not completely removed after the retreatment with 10% NaOCl. Above results indicate that the dissolution of collagen in acid conditioned dentin layer by NaOCl solution can not be achieved completely and the collagens contribute to the resin - dentin adhesion considerably.

• 대한소아치과학회지
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• 제46권1호
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• pp.21-28
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• 2019

이 연구의 목적은 브라켓 부착 시 Conventional primer (CP), Moisture insensitive primer (MIP), Self-etching primer (SEP)을 사용하였을 때의 전단결합강도를 비교하고, 타액 오염 여부와 타액 오염의 시기가 전단결합강도에 미치는 영향을 평가하는 것이다. 총 135개의 소의 하악 절치가 연구에 사용되었다. 시편은 I, II, III 3개의 군으로 나누어 CP, MIP, SEP를 사용하여 브라켓을 부착하였다. 각 군은 3개의 하위군으로 나누어져서 타액 오염이 없는 군, 타액 오염 후 프라이머를 도포한 군, 프라이머 도포 후 타액 오염이 있는 군으로 설정하고 전단결합강도를 측정하였다. 연구 결과, 건조한 환경에서 전단결합강도는 CP, MIP, SEP의 순서로 높게 나타났다. CP는 타액 오염이 있는 경우에는 유의한 전단결합강도의 저하를 보였다. MIP, SEP를 사용한 경우에는 프라이머 도포 전 후 타액 오염이 있는 경우에 약간의 전단결합강도의 저하를 보였지만, 건조한 환경에서와 비교하여 유의한 차이는 보이지 않았다. 따라서 브라켓 접착 시 타액의 격리가 힘든 상황에서는 MIP 또는 SEP의 사용이 브라켓 전단결합강도의 저하를 방지하기 위하여 유용할 것으로 보인다.

• Restorative Dentistry and Endodontics
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• 제45권3호
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• pp.36.1-36.10
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• 2020

Objectives: This study aims to assess the effect of universal adhesives pretreatment on the bond strength of resin-modified glass ionomer cement to dentin. Materials and Methods: Fifty caries-free human third molars were employed. The teeth were randomly assigned into five groups (n = 10) based on dentin surface pretreatments: Single Bond Universal (3M Oral Care), Gluma Bond Universal (Heraeus Kulzer), Prime&Bond Elect (Dentsply), Cavity Conditioner (GC) and control (no surface treatment). After Fuji II LC (GC) was bonded to the dentin surfaces, the specimens were stored for 7 days at 37℃. The specimens were segmented into microspecimens, and the microspecimens were subjugated to microtensile bond strength testing (1.0 mm/min). The modes of failure analyzed using a stereomicroscope and scanning electron microscopy. Data were statistically analyzed with one-way analysis of variance and Duncan tests (p = 0.05). Results: The surface pretreatments with the universal adhesives and conditioner increased the bond strength of Fuji II LC to dentin (p < 0.05). Single Bond Universal and Gluma Bond Universal provided higher bond strength to Fuji II LC than Cavity Conditioner (p < 0.05). The bond strengths obtained from Prime&Bond Elect and Cavity Conditioner were not statistically different (p > 0.05). Conclusions: The universal adhesives and polyacrylic acid conditioner could increase the bond strength of resin-modified glass ionomer cement (RMGIC) to dentin. The use of universal adhesives before the application of RMGIC may be more beneficial in improving bond strength.

• Restorative Dentistry and Endodontics
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• 제33권6호
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• pp.545-552
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• 2008

본 연구의 목적은 NaOCl로 처리된 치수강 상아질에 total-etching adhesive system(single bond, 3M-ESPE, St Paul, MN, USA)을 적용할 때 미세인장결합강도에서 sodium ascorbate가 미치는 영향을 평가하는 것이다. 발치된 건전한 인간 대구치의 치수강 내면을 다음과 같이 처리하였다. 1군, 0.9% NaCl로 세척; 2군, 5.25% NaOCl로 세척; 3군, 5.25% NaOCl로 세척한 후 10% sodium ascorbate를 1분간 적용; 4군, 5.25% NaOCl로 세척한 후 10% sodium ascorbate를 1분간 적용하고 다시 10ml 물로 수세; 5군, 5.25% NaOCl로 세척한 후 10% sodium ascorbate를 5분간 적용; 6군, 5.25% NaOCl로 세척한 후 10% sodium ascorbate를 5분간 적용하고 다시 10ml 물로 수세; 7군, 5.25% NaOCl로 세척한 후 10% sodium ascorbate를 10분간 적용; 8군, 5.25% NaOCl로 세척한 후 10% sodium ascorbate를 10분간 적용하고 다시 10ml 물로 수세. 처리된 시편들은 total-etching adhesive system(Single bond)으로 처리한 후 composite resin(Z250)으로 충전하고, 미세인장강도를 측정하기 전 24시 간 동안 보관하였다. 분석 결과 NaOCl 처리 군(2군)은 다른 실험군들에 비해 유의성 있게 낮은 결합 강도를 보였다. NaCl 처리 군(1군)과 sodium ascorbate 처리 군(3-8군)은 유의성 있는 차이가 없었다. 이번 연구 결과는 NaOCl로 처리한 치수강 상아질의 Single bond에 대한 미세인장결합강도는 감소되며, 10% sodium ascorbate를 추가적으로 처리하였을 때 감소된 결합력이 회복됨을 보여주었다. Sodium ascorbate의 다양한 처리시간은 결합력에 영향을 미치지 않았다.

• The Journal of Advanced Prosthodontics
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• 제5권4호
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• pp.382-387
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• 2013

PURPOSE. Although several surface treatments have been recently investigated both under in vitro and in vivo conditions, controversy still exists regarding the selection of the most appropriate zirconia surface pre-treatment. The purpose of this study was to evaluate the effect of alumina (Al) and aluminium nitride (AlN) coating on the shear bond strength of adhesive resin cement to zirconia core. MATERIALS AND METHODS. Fifty zirconia core discs were divided into 5 groups; air particle abrasion with 50 ${\mu}m$ aluminum oxide particles ($Al_2O_3$), polishing + Al coating, polishing + AlN coating, air particle abrasion with 50 ${\mu}m$ $Al_2O_3$ + Al coating and air particle abrasion with 50 ${\mu}m$ $Al_2O_3$ + AlN coating. Composite resin discs were cemented to each of specimens. Shear bond strength (MPa) was measured using a universal testing machine. The effects of the surface preparations on each specimen were examined with scanning electron microscope (SEM). Data were statistically analyzed by one-way ANOVA (${\alpha}$=.05). RESULTS. The highest bond strengths were obtained by air abrasion with 50 ${\mu}m$ $Al_2O_3$, the lowest bond strengths were obtained in polishing + Al coating group (P<.05). CONCLUSION. Al and AlN coatings using the reactive magnetron sputtering technique were found to be ineffective to increase the bond strength of adhesive resin cement to zirconia core.

• The Journal of Advanced Prosthodontics
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• 제7권4호
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• pp.312-316
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• 2015

PURPOSE. This study aimed to present the clinical applicability of restorations fabricated by a new method, by comparing the bond strength of between ceramic powder with different coefficient of thermal expansion and alloys fabricated by Selective laser sintering (SLS). MATERIALS AND METHODS. Fifty Co-Cr alloy specimens ($25.0{\times}3.0{\times}0.5mm$) were prepared by SLS and fired with the ceramic ($8.0{\times}3.0{\times}0.5mm$) (ISO 9693:1999). For comparison, ceramics with different coefficient of thermal expansion were used. The bond strength was measured by three-point bending testing and surfaces were observed with FE-SEM. Results were analyzed with a one-way ANOVA (${\alpha}$=.05). RESULTS. The mean values of Duceram Kiss ($61.18{\pm}6.86MPa$), Vita VM13 ($60.30{\pm}7.14MPa$), Ceramco 3 ($58.87{\pm}5.33MPa$), Noritake EX-3 ($55.86{\pm}7.53MPa$), and Vintage MP ($55.15{\pm}7.53MPa$) were found. No significant difference was observed between the bond strengths of the various metal-ceramics. The surfaces of the specimens possessed minute gaps between the additive manufactured layers. CONCLUSION. All the five powders have bond strengths higher than the required 25 MPa minimum (ISO 9693); therefore, various powders can be applied to metal structures fabricated by SLS.