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Sample records for metal-ceramic bond strength

  1. Metal-ceramic bond strength of Co-Cr alloy fabricated by selective laser melting.

    Science.gov (United States)

    Xiang, Nan; Xin, Xian-Zhen; Chen, Jie; Wei, Bin

    2012-06-01

    This study was to evaluated the metal-ceramic bond strength of a Co-Cr dental alloy prepared using a selective laser melting (SLM) technique. Two groups comprised of twenty Co-Cr metal bars each were prepared using either a SLM or traditional lost-wax casting method. Ten bars from each group were moulded into standard ISO 9693:1999 dimensions of 25 mm × 3 mm × 0.5 mm with 1.1 mm of porcelain fused onto an 8 mm × 3 mm rectangular area in the centre of each bar. Metal-ceramic bonding was assessed using a three-point bending test. Fracture mode analysis and area fraction of adherence porcelain (AFAP) were determined by measuring Si content of specimens by SEM/EDS. Student's t-test within the groups demonstrated no significant difference for the mean bond strength between the SLM and traditional cast sample groups. While SEM/EDS analysis indicated a mixed fracture mode on the debonding interface of both the SLM and the cast groups, the SLM group showed significantly more porcelain adherence than the control group (p<0.05). The SLM metal-ceramic system exhibited a bonding strength that exceeds the requirement of ISO 9691:1999(E) and it even showed a better behaviour in porcelain adherence test comparable to traditional cast methods. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Effect of layered manufacturing techniques, alloy powders, and layer thickness on metal-ceramic bond strength.

    Science.gov (United States)

    Ekren, Orhun; Ozkomur, Ahmet; Ucar, Yurdanur

    2018-03-01

    Direct metal laser sintering (DMLS) and direct metal laser melting (DMLM) have become popular for fabricating the metal frameworks of metal-ceramic restorations. How the type of layered manufacturing device, layer thickness, and alloy powder may affect the bond strength of ceramic to metal substructure is unclear. The purpose of this in vitro study was to evaluate the bond strength of dental porcelain to metal frameworks fabricated using different layered manufacturing techniques (DMLS and DMLM), Co-Cr alloy powders, and layer thicknesses and to evaluate whether a correlation exists between the bond strength and the number of ceramic remnants on the metal surface. A total of 75 bar-shaped metal specimens (n=15) were fabricated using either DMLS or DMLM. The powder alloys used were Keramit NP-S and EOS-Cobalt-Chrome SP-2 with layer thicknesses of 20 μm and 30 μm. After ceramic application, the metal-ceramic bond strength was evaluated with a 3-point-bend test. Three-way ANOVA followed by the Tukey honest significance difference test were used for statistical analysis (α=.05). De-bonding surface microstructure was observed with scanning electron microscopy. Energy dispersive spectroscopy analysis was conducted to evaluate the correlation between ceramic remnants on the metal surface and bond strength values. The mean bond strength value of DMLS was significantly higher than that of DMLM. While no statistically significant difference was found between layer thicknesses, alloy powders closely affected bond strength. Statistical comparisons revealed that the highest bond strength could be achieved with DMLS-Cobalt-Chrome SP2-20μm, and the lowest bond strength was observed in DMLS-Keramit NP-S-20μm (P≤.05). No correlation was found between porcelain remnants on the metal surface and bond strength values. The layered manufacturing device and the alloy powders evaluated in the current study closely affected the bond strength of dental porcelain to a metal framework

  3. Correlation between metal-ceramic bond strength and coefficient of linear thermal expansion difference

    Directory of Open Access Journals (Sweden)

    Stella Crosara Lopes

    2009-04-01

    Full Text Available The purpose of this study was to evaluate the metal-ceramic bond strength (MCBS of 6 metal-ceramic pairs (2 Ni-Cr alloys and 1 Pd-Ag alloy with 2 dental ceramics and correlate the MCBS values with the differences between the coefficients of linear thermal expansion (CTEs of the metals and ceramics. Verabond (VB Ni-Cr-Be alloy, Verabond II (VB2, Ni-Cr alloy, Pors-on 4 (P, Pd-Ag alloy, and IPS (I and Duceram (D ceramics were used for the MCBS test and dilatometric test. Forty-eight ceramic rings were built around metallic rods (3.0 mm in diameter and 70.0 mm in length made from the evaluated alloys. The rods were subsequently embedded in gypsum cast in order to perform a tensile load test, which enabled calculating the CMBS. Five specimens (2.0 mm in diameter and 12.0 mm in length of each material were made for the dilatometric test. The chromel-alumel thermocouple required for the test was welded into the metal test specimens and inserted into the ceramics. ANOVA and Tukey's test revealed significant differences (p=0.01 for the MCBS test results (MPa, with PI showing higher MCBS (67.72 than the other pairs, which did not present any significant differences. The CTE (10-6 oC-1 differences were: VBI (0.54, VBD (1.33, VB2I (-0.14, VB2D (0.63, PI (1.84 and PD (2.62. Pearson's correlation test (r=0.17 was performed to evaluate of correlation between MCBS and CTE differences. Within the limitations of this study and based on the obtained results, there was no correlation between MCBS and CTE differences for the evaluated metal-ceramic pairs.

  4. Correlation between metal-ceramic bond strength and coefficient of linear thermal expansion difference.

    Science.gov (United States)

    Lopes, Stella Crosara; Pagnano, Valéria Oliveira; Rollo, João Manuel Domingos de Almeida; Leal, Mônica Barbosa; Bezzon, Osvaldo Luiz

    2009-01-01

    The purpose of this study was to evaluate the metal-ceramic bond strength (MCBS) of 6 metal-ceramic pairs (2 Ni-Cr alloys and 1 Pd-Ag alloy with 2 dental ceramics) and correlate the MCBS values with the differences between the coefficients of linear thermal expansion (CTEs) of the metals and ceramics. Verabond (VB) Ni-Cr-Be alloy, Verabond II (VB2), Ni-Cr alloy, Pors-on 4 (P), Pd-Ag alloy, and IPS (I) and Duceram (D) ceramics were used for the MCBS test and dilatometric test. Forty-eight ceramic rings were built around metallic rods (3.0 mm in diameter and 70.0 mm in length) made from the evaluated alloys. The rods were subsequently embedded in gypsum cast in order to perform a tensile load test, which enabled calculating the CMBS. Five specimens (2.0 mm in diameter and 12.0 mm in length) of each material were made for the dilatometric test. The chromel-alumel thermocouple required for the test was welded into the metal test specimens and inserted into the ceramics. ANOVA and Tukey's test revealed significant differences (p=0.01) for the MCBS test results (MPa), with PI showing higher MCBS (67.72) than the other pairs, which did not present any significant differences. The CTE (10(-6) oC(-1)) differences were: VBI (0.54), VBD (1.33), VB2I (-0.14), VB2D (0.63), PI (1.84) and PD (2.62). Pearson's correlation test (r=0.17) was performed to evaluate of correlation between MCBS and CTE differences. Within the limitations of this study and based on the obtained results, there was no correlation between MCBS and CTE differences for the evaluated metal-ceramic pairs.

  5. Microstructure, hardness, corrosion resistance and porcelain shear bond strength comparison between cast and hot pressed CoCrMo alloy for metal-ceramic dental restorations.

    Science.gov (United States)

    Henriques, B; Soares, D; Silva, F S

    2012-08-01

    The purpose of this study was to compare the microstructure, hardness, corrosion resistance and metal-porcelain bond strength of a CoCrMo dental alloy obtained by two routes, cast and hot pressing. CoCrMo alloy substrates were obtained by casting and hot pressing. Substrates' microstructure was examined by the means of Optical Microscopy (OM) and by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). Hardness tests were performed in a microhardness indenter. The electrochemical behavior of substrates was investigated through potentiodynamic tests in a saline solution (8g NaCl/L). Substrates were bonded to dental porcelain and metal-porcelain bond strength was assessed by the means of a shear test performed in a universal test machine (crosshead speed: 0.5 mm/min) until fracture. Fractured surfaces as well as undestroyed interface specimens were examined with Stereomicroscopy and SEM-EDS. Data was analyzed with Shapiro-Wilk test to test the assumption of normality. The t-test (pmicrostructures whereas hot pressed specimens exhibited a typical globular microstructure with a second phase spread through the matrix. The hardness registered for hot pressed substrates was greater than that of cast specimens, 438±24HV/1 and 324±8HV/1, respectively. Hot pressed substrates showed better corrosion properties than cast ones, i.e. higher OCP; higher corrosion potential (E(corr)) and lower current densities (i(corr)). No significant difference was found (p<0.05) in metal-ceramic bond strength between cast (116.5±6.9 MPa) and hot pressed (114.2±11.9 MPa) substrates. The failure type analysis revealed an adhesive failure for all specimens. Hot pressed products arise as an alternative to cast products in dental prosthetics, as they impart enhanced mechanical and electrochemical properties to prostheses without compromising the metal-ceramic bond strength. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Effects of at-home and in-office bleaching agents on the shear bond strength of metal, ceramic, and composite brackets to enamel.

    Science.gov (United States)

    Rahul, M; Kumar, P Anil; Nair, Amal S; Mathew, Shino; Amaladas, Antony Shijoy; Ommen, Anna

    2017-01-01

    This study aimed to evaluate the effects of at-home and in-office bleaching on the shear bond strength (SBS) of metal, ceramic, and composite orthodontic brackets and to compare their SBSs. A total of 96 human lower premolar teeth were used for this study. Six teeth were used for scanning electron microscopic study while the remaining ninety were divided into three equal groups. Each group was further subdivided into three subgroups with ten samples each. Three protocols were used. In the at-home bleaching group (n = 30), opalescence non-PF (potassium nitrate and fluoride) bleaching agent (10% carbamide peroxide) was applied onto the teeth daily for 14 days and left for 8 h each day. Teeth in the in-office group (n = 30) were treated twice in consecutive days with Opalescence boost PF (40% hydrogen peroxide). After bleaching, the specimens were stored in distilled water for 1 day before bonding. SBS testing was performed on all teeth using Instron universal testing machine. Analysis of variance indicated a significant difference (P brackets in control group (Ib) and minimum was shown by composite brackets of in-office bleached group (IIIc). The results showed that at-home bleaching did not affect the SBS significantly whereas in-office bleaching reduced SBS of metal, ceramic, and composite brackets significantly. It is preferable to use metal or ceramic brackets than composite brackets for bonding 24 h after bleaching.

  7. Metal-ceramic bond strength between a feldspathic porcelain and a Co-Cr alloy fabricated with Direct Metal Laser Sintering technique.

    Science.gov (United States)

    Dimitriadis, Konstantinos; Spyropoulos, Konstantinos; Papadopoulos, Triantafillos

    2018-02-01

    The aim of the present study was to record the metal-ceramic bond strength of a feldspathic dental porcelain and a Co-Cr alloy, using the Direct Metal Laser Sintering technique (DMLS) for the fabrication of metal substrates. Ten metal substrates were fabricated with powder of a dental Co-Cr alloy using DMLS technique (test group) in dimensions according to ISO 9693. Another ten substrates were fabricated with a casing dental Co-Cr alloy using classic casting technique (control group) for comparison. Another three substrates were fabricated using each technique to record the Modulus of Elasticity ( E ) of the used alloys. All substrates were examined to record external and internal porosity. Feldspathic porcelain was applied on the substrates. Specimens were tested using the three-point bending test. The failure mode was determined using optical and scanning electron microscopy. The statistical analysis was performed using t-test. Substrates prepared using DMLS technique did not show internal porosity as compared to those produced using the casting technique. The E of control and test group was 222 ± 5.13 GPa and 227 ± 3 GPa, respectively. The bond strength was 51.87 ± 7.50 MPa for test group and 54.60 ± 6.20 MPa for control group. No statistically significant differences between the two groups were recorded. The mode of failure was mainly cohesive for all specimens. Specimens produced by the DMLS technique cover the lowest acceptable metal-ceramic bond strength of 25 MPa specified in ISO 9693 and present satisfactory bond strength for clinical use.

  8. Effects of at-home and in-office bleaching agents on the shear bond strength of metal, ceramic, and composite brackets to enamel

    Directory of Open Access Journals (Sweden)

    M Rahul

    2017-01-01

    Full Text Available Aims and Objectives: This study aimed to evaluate the effects of at-home and in-office bleaching on the shear bond strength (SBS of metal, ceramic, and composite orthodontic brackets and to compare their SBSs. Subjects and Methods: A total of 96 human lower premolar teeth were used for this study. Six teeth were used for scanning electron microscopic study while the remaining ninety were divided into three equal groups. Each group was further subdivided into three subgroups with ten samples each. Three protocols were used. In the at-home bleaching group (n = 30, opalescence non-PF (potassium nitrate and fluoride bleaching agent (10% carbamide peroxide was applied onto the teeth daily for 14 days and left for 8 h each day. Teeth in the in-office group (n = 30 were treated twice in consecutive days with Opalescence boost PF (40% hydrogen peroxide. After bleaching, the specimens were stored in distilled water for 1 day before bonding. SBS testing was performed on all teeth using Instron universal testing machine. Results: Analysis of variance indicated a significant difference (P < 0.005 among the groups. Maximum SBS was shown by ceramic brackets in control group (Ib and minimum was shown by composite brackets of in-office bleached group (IIIc. Conclusions: The results showed that at-home bleaching did not affect the SBS significantly whereas in-office bleaching reduced SBS of metal, ceramic, and composite brackets significantly. It is preferable to use metal or ceramic brackets than composite brackets for bonding 24 h after bleaching.

  9. Experimental Investigations on the Influence of Adhesive Oxides on the Metal-Ceramic Bond

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    Susanne Enghardt

    2015-01-01

    Full Text Available The objective of this study was to test the influence of selected base metals, which act as oxide formers, on the metal-ceramic bond of dental veneer systems. Using ion implantation techniques, ions of Al, In and Cu were introduced into near-surface layers of a noble metal alloy containing no base metals. A noble metal alloy with base metals added for oxide formation was used as a reference. Both alloys were coated with a low-temperature fusing dental ceramic. Specimens without ion implantation or with Al2O3 air abrasion were used as controls. The test procedures comprised the Schwickerath shear bond strength test (ISO 9693-1, profile height (surface roughness measurements (ISO 4287; ISO 4288; ISO 25178, scanning electron microscopy (SEM imaging, auger electron spectroscopy (AES and energy dispersive X-ray analysis (EDX. Ion implantation resulted in no increase in bond strength. The highest shear bond strengths were achieved after oxidation in air and air abrasion with Al2O3 (41.5 MPa and 47.8 MPa respectively. There was a positive correlation between shear bond strength and profile height. After air abrasion, a pronounced structuring of the surface occurred compared to ion implantation. The established concentration shifts in alloy and ceramic could be reproduced. However, their positive effects on shear bond strength were not confirmed. The mechanical bond appears to be of greater importance for metal-ceramic bonding.

  10. Evaluation of metal-ceramic bond characteristics of three dental Co-Cr alloys prepared with different fabrication techniques.

    Science.gov (United States)

    Wang, Hongmei; Feng, Qing; Li, Ning; Xu, Sheng

    2016-12-01

    Limited information is available regarding the metal-ceramic bond strength of dental Co-Cr alloys fabricated by casting (CAST), computer numerical control (CNC) milling, and selective laser melting (SLM). The purpose of this in vitro study was to evaluate the metal-ceramic bond characteristics of 3 dental Co-Cr alloys fabricated by casting, computer numerical control milling, and selective laser melting techniques using the 3-point bend test (International Organization for Standardization [ISO] standard 9693). Forty-five specimens (25×3×0.5 mm) made of dental Co-Cr alloys were prepared by CAST, CNC milling, and SLM techniques. The morphology of the oxidation surface of metal specimens was evaluated by scanning electron microscopy (SEM). After porcelain application, the interfacial characterization was evaluated by SEM equipped with energy-dispersive spectrometry (EDS) analysis, and the metal-ceramic bond strength was assessed with the 3-point bend test. Failure type and elemental composition on the debonding interface were assessed by SEM/EDS. The bond strength was statistically analyzed by 1-way ANOVA and Tukey honest significant difference test (α=.05). The oxidation surfaces of the CAST, CNC, and SLM groups were different. They were porous in the CAST group but compact and irregular in the CNC and SLM groups. The metal-ceramic interfaces of the SLM and CNC groups showed excellent combination compared with those of the CAST group. The bond strength was 37.7 ±6.5 MPa for CAST, 43.3 ±9.2 MPa for CNC, and 46.8 ±5.1 MPa for the SLM group. Statistically significant differences were found among the 3 groups tested (P=.028). The debonding surfaces of all specimens exhibited cohesive failure mode. The oxidation surface morphologies and thicknesses of dental Co-Cr alloys are dependent on the different fabrication techniques used. The bond strength of all 3 groups exceed the minimum acceptable value of 25 MPa recommended by ISO 9693; hence, dental Co-Cr alloy

  11. [The bonding mechanisms of base metals for metal-ceramic crown microstructure analysis of bonding agent and gold bond between porcelain and base metals].

    Science.gov (United States)

    Wang, C C; Hsu, C S

    1996-06-01

    layer. 5. A white-grayish oxidized layer appeared at the metal-ceramic interfaces but the thickness of oxidized layer was not obviously different. 6. The use of bonding agent at metal-ceramic interface leads to the deposition of many Sn elements at about 40 microns range within the porcelain surface. 7. Second interaction phases at the porcelain layer appeared when gold bonding agent was used, and a 50-100 microns microleakage occurred at the metal-ceramic interface.

  12. Electric strength of metal-ceramic brazed units of thermionic energy converters in cesium vapours

    International Nuclear Information System (INIS)

    Belousenko, A.P.; Vasilchenko, A.V.; Nikolaev, Y.V.

    1989-01-01

    The investigation of electric strength characteristics of the hollow metal-ceramic brazed units of thermionic energy converters with the insulator 1 = 10-50 mm from polycrystal aluminum oxide at the temperature T = 450-750 degrees and the cesium vapour pressure P Cs = 10 - 1 -10 3 Pa has been carried out. The experimental dependencies of the break-down voltage of the brazed units on the temperature, parameter P Cs · 1 and the value of surface electric resistance of the insulators are given as well as the empiric equations obtained with the help of experimental data for calculating the break-down voltage. A mechanism of ceramic insulator influence on electric strength characteristics of the cesium gap is investigated. A breakdown model explaining this influence is proposed

  13. Effects of soldering methods on tensile strength of a gold-palladium metal ceramic alloy.

    Science.gov (United States)

    Ghadhanfari, Husain A; Khajah, Hasan M; Monaco, Edward A; Kim, Hyeongil

    2014-10-01

    The tensile strength obtained by conventional postceramic application soldering and laser postceramic welding may require more energy than microwave postceramic soldering, which could provide similar tensile strength values. The purpose of the study was to compare the tensile strength obtained by microwave postceramic soldering, conventional postceramic soldering, and laser postceramic welding. A gold-palladium metal ceramic alloy and gold-based solder were used in this study. Twenty-seven wax specimens were cast in gold-palladium noble metal and divided into 4 groups: laser welding with a specific postfiller noble metal, microwave soldering with a postceramic solder, conventional soldering with the same postceramic solder used in the microwave soldering group, and a nonsectioned control group. All the specimens were heat treated to simulate a normal porcelain sintering sequence. An Instron Universal Testing Machine was used to measure the tensile strength for the 4 groups. The means were analyzed statistically with 1-way ANOVA. The surface and fracture sites of the specimens were subjectively evaluated for fracture type and porosities by using a scanning electron microscope. The mean (standard deviation) ultimate tensile strength values were as follows: nonsectioned control 818 ±30 MPa, microwave 516 ±34 MPa, conventional 454 ±37 MPa, and laser weld 191 ±39 MPa. A 1-way ANOVA showed a significant difference in ultimate tensile strength among the groups (F3,23=334.5; Ptensile strength for gold and palladium noble metals than either conventional soldering or laser welding. Conventional soldering resulted in a higher tensile strength than laser welding. Under the experimental conditions described, either microwave or conventional postceramic soldering would appear to satisfy clinical requirements related to tensile strength. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. Bond strength of masonry

    NARCIS (Netherlands)

    Pluijm, van der R.; Vermeltfoort, A.Th.

    1992-01-01

    Bond strength is not a well defined property of masonry. Normally three types of bond strength can be distinguished: - tensile bond strength, - shear (and torsional) bond strength, - flexural bond strength. In this contribution the behaviour and strength of masonry in deformation controlled uniaxial

  15. Surface analysis applied to metal-ceramic and bioceramic interfacial bonding

    International Nuclear Information System (INIS)

    Smart, R.St.C.; Arora, P.S.; Steveson, M.; Kawashima, N.; Cavallaro, G.P.; Ming, H.; Skinner, W.M.

    1999-01-01

    Full text: Low temperature plasma reactions, combined with sol-gel coatings, have been used to produce a variety of ceramic surface layers on metal substrates and interfacial layers between metals and oxides or other ceramics. These layers can be designed to be compositionally and functionally graded from the metal to bulk ceramic material, eg. silica, alumina, hydroxyapatite. The graded layers are generally <50nm thick, continuous, fully bonded to the substrate and deformable without disbonding. The objectives in design of these layers have been to produce: metal surfaces protected from oxidation, corrosion and acid attack; improved metal-ceramic bonding; and bioceramic titanium-based interfaces to bioactive hydroxyapatite for improved dental and medical implants. Modified Auger parameter studies for Si in XPS spectra show that the structure on the metal surfaces grades from amorphous, dehydroxylated silica on the outer surface through layer silicates, chain silicates, pyrosilicates to orthosilicates close to the metal interface. At the metal interface, detached grains of the metal are imaged with interpenetration of the oxide and silicate species linking the layer to the oxidised metal surface. The ∼30nm layer has a substantially increased frictional load compared with the untreated oxidised metal, i.e. behaviour consistent with either stronger adhesion of the coating to the substrate or a harder surface. The composition, structure and thickness of these layers can be controlled by the duration of each plasma reaction and the choice of the final reagent. The mechanisms of reaction in each process step have been elucidated with a combination of XPS, TOF-SIMS, TEM, SEM and FTIR. Similar, graded titanium/oxide/silicate/silica ceramic surface layers have been shown to form using the low temperature plasma reactions on titanium alloys used in medical and dental implants. Thicker (i.e. μm) overlayers of ceramic materials can be added to the graded surface layers

  16. Methods for surface treating metals, ceramics, and plastics before adhesive bonding

    International Nuclear Information System (INIS)

    Althouse, L.P.

    1976-01-01

    Methods for pretreating the surfaces of metals, ceramics, and plastics before they are coated with adhesive and used in assembly are described. The treatments recommended have been used successfully in the laboratory at LLL. Many are used in the assembly of nuclear devices. However, an unusual alloy or complex configuration may require trials before a specific surface treatment is chosen

  17. Investigation of the bonding strength and bonding mechanisms of SOFCs interconnector-electrode interfaces

    Czech Academy of Sciences Publication Activity Database

    Boccaccini, D. N.; Ševeček, O.; Frandsen, L. H.; Dlouhý, Ivo; Molin, S.; Cannio, M.; Hjelm, J.; Hendriksen, P. V.

    2016-01-01

    Roč. 162, č. 1 (2016), s. 250-253 ISSN 0167-577X Institutional support: RVO:68081723 Keywords : Metal-ceramic bond strength * Schwickerath crack-initiation test * SOC interfaces Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 2.572, year: 2016

  18. A comparison of tensile bond strengths of resin-retained prostheses made using five alloys.

    Science.gov (United States)

    Rubo, J H; Pegoraro, L F; Ferreira, P M

    1996-01-01

    This in vitro study evaluated the bond strength of metal frameworks cast using Ni-Cr, Ni-Cr-Be, Cu-Al, type IV gold, and noble metal ceramic alloy with and without tin electroplating. The castings were luted to human teeth using Panavia Ex resin. It was found that tin electroplating had a negative effect for the Cu-Al and type IV gold alloys and a positive effect for gold for metal ceramic restorations. The best results were obtained using the Ni-Cr alloy.

  19. Fatigue Fracture Strength of Implant-Supported Full Contour Zirconia and Metal Ceramic Fixed Partial Dentures

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    Fariborz Vafaee

    2017-10-01

    Full Text Available Objectives: Zirconia restorations have been suggested as a more durable and more appealing alternative to metal restorations. However, their mechanical properties may be negatively affected by fatigue due to superficial stresses or low temperature degradation. This study aimed to assess the fatigue fracture strength of three-unit implant-supported full contour zirconia and pre-sintered cobalt-chromium (Co-Cr alloy posterior fixed partial dentures (FPDs.Materials and Methods: In this in-vitro experimental study, 28 posterior three-unit implant-supported FPDs were fabricated of full contour zirconia and pre-sintered Co-Cr alloy, and were cemented on implant abutments. To simulate the oral environment, FPDs were subjected to 10,000 thermal cycles between 5-55°C for 30 seconds, and were then transferred to a chewing simulator (100,000 cycles, 50 N, 0.5 Hz. Afterwards, fatigue fracture strength was measured using a universal testing machine. Data were analyzed by Mann-Whitney U test.Results: The mean and standard deviation of fracture strength were 2108.6±440.1 N in full contour zirconia, and 3499.9±1106.5 N in pre-sintered Co-Cr alloy. According to Mann- Whitney U test, the difference in this respect was statistically significant between the two groups (P=0.007.Conclusions: Since the fracture strength values obtained in the two groups were significantly higher than the maximum mean masticatory load in the oral environment, both materials can be used for fabrication of posterior three-unit FPDs, depending on the esthetic demands of patients.

  20. [Research progress in CoCr metal-ceramic alloy fabricated by selective laser melting].

    Science.gov (United States)

    Yan, X; Lin, H

    2018-02-09

    Cobalt-chromium alloys have been applied to dental porcelain fused to metal (PFM) restorations over the past decades owing to their excellent corrosion resistance, good biocompatibility and low price. The production of CoCr metal-ceramic restorations has always been based on traditional lost-wax casting techniques. However, in recent years, selective laser melting (SLM) is becoming more and more highly valued by dental laboratories and dental practitioners due to its individuation, precision and efficiency. This paper mainly reviews the recent researches on the production process of copings, microstructure, mechanical property, metal-ceramic bond strength, fit of copings, corrosion resistance and biocompatibility of SLM CoCr metal-ceramic alloy.

  1. A contribution to the study of metal-ceramic bonding by direct vacuum brazing with reactive metals

    International Nuclear Information System (INIS)

    Guimaraes, A.S.

    1988-01-01

    Wettability and bonding tests were utilized to evaluate the behaviour of various specials alloys, for work at high temperature under vacuum, for the inter-bonding of silicon carbide, alumina ceramic, graphite (for electrical applications) and petroleum coke and their joining with themselves as the metals titanium, molybdenum, nickel and copper. The joints exhibiting effective bonding were investigated by means of optical microscopy, scanning electron microscopy and X-rays diffraction. Elemental mapping of the constituents and quantitative chemical microanalysis were also undertaken, via the energy dispersive analysis of X-rays (SEM/EDS). On the basis of the results the possible mechanisms of bond-formation have been discussed. It was verified that: a) of the filler metals studied, those which exhibited effective wettability on all the above materials were: 49Cu-49Ti-2Be, Zircaloy4-5Be and a commercial alloy Ticusil, which consisted of a Cu-Ag eutectic with a small addition of pure Ti, of nominal composition 26.7Cu-68.8Ag-4.5Ti; b) the alloys with high levels of reactive metals such as Ti and Zr tended to form low ductility bonds due to the formation of hard, brittle phases; c) the copper suffered pronounced erosion when in direct contact with alloys of high Ti and Zr contents, due to the formation of phases whose melting points were below the brazing temperature of those materials; e) the compounds detected as reaction products were identified as, TiC in the samples rich in carbon, such as the SiC ceramic and graphite joints, or the oxides Cu2Ti2O5 and Cu3TiO4 in the bonding of alumina to alloys including Ti in their composition or in that of the filler metal, proving that the effectiveness of the bond is dependent upon an initial and indispensable chemical bonding. (author)

  2. Effect of heating palladium-silver alloys on ceramic bond strength.

    Science.gov (United States)

    Li, Jie-yin; Li, Rui-nan; Chang, Shao-hai; Zhuang, Pei-lin; Liao, Juan-kun; Ye, Xiu-hua; Ye, Jian-tao

    2015-11-01

    The effects of different heat treatments on the internal oxidation and metal-ceramic bond in Pd-Ag alloys with different trace elements require further documentation. The purpose of this in vitro study was to determine whether heat treatment affects the metal-ceramic bond strength of 2 Pd-Ag alloys containing different trace elements. Thirteen cast specimens (25×3×0.5 mm) from each of 2 Pd-Ag alloy groups (W-1 and Argelite 61+3) were allocated to heat treatments before porcelain application: heating under reduced atmospheric pressure of 0.0014 MPa and 0.0026 MPa and heating under normal atmospheric pressure. Bond strengths were evaluated using a 3-point bending test according to ISO9693. Results were analyzed using 2-way ANOVA and Tukey HSD test (α=.05). Visual observation was used to determine the failure types of the fractured specimens. Scanning electron microscopy and energy dispersive spectroscopy were used to study morphologies, elemental compositions, and distributions in the specimens. The W-1 group had a mean bond strength significantly higher than that of Argelite 61+3 (PHeating under reduced atmospheric pressures of 0.0014 MPa and 0.0026 MPa resulted in similar bond strengths (P=.331), and both pressures had significantly higher bond strengths than that of heating under normal atmospheric pressure (P=.002, PHeating under different air pressures resulted in Pd-Ag alloys that contained either Sn or In and Ga, with various degrees of internal oxidation and different quantities of metallic nodules. Heating under reduced atmospheric pressure effectively improved the bond strength of the ceramic-to-Pd-Ag alloys. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  3. Viscoelastic analysis of a dental metal-ceramic system

    Science.gov (United States)

    Özüpek, Şebnem; Ünlü, Utku Cemal

    2012-11-01

    Porcelain-fused-to-metal (PFM) restorations used in prosthetic dentistry contain thermal stresses which develop during the cooling phase after firing. These thermal stresses coupled with the stresses produced by mechanical loads may be the dominant reasons for failures in clinical situations. For an accurate calculation of these stresses, viscoelastic behavior of ceramics at high temperatures should not be ignored. In this study, the finite element technique is used to evaluate the effect of viscoelasticity on stress distributions of a three-point flexure test specimen, which is the current international standard, ISO 9693, to characterize the interfacial bond strength of metal-ceramic restorative systems. Results indicate that the probability of interfacial debonding due to normal tensile stress is higher than that due to shear stress. This conclusion suggests modification of ISO 9693 bond strength definition from one in terms of the shear stress only to that accounting for both normal and shear stresses.

  4. Effect of laser welding on the titanium ceramic tensile bond strength

    Directory of Open Access Journals (Sweden)

    Rodrigo Galo

    2011-08-01

    Full Text Available Titanium reacts strongly with elements, mainly oxygen at high temperature. The high temperature of titanium laser welding modifies the surface, and may interfere on the metal-ceramic tensile bond strength. OBJECTIVE: The influence of laser welding on the titanium-ceramic bonding has not yet been established. The purpose of this in vitro study was to analyze the influence of laser welding applied to commercially pure titanium (CpTi substructure on the bond strength of commercial ceramic. The influence of airborne particle abrasion (Al2O3 conditions was also studied. MATERIAL AND METHODS: Forty CpTi cylindrical rods (3 mm x 60 mm were cast and divided into 2 groups: with laser welding (L and without laser welding (WL. Each group was divided in 4 subgroups, according to the size of the particles used in airborne particle abrasion: A - Al2O3 (250 µm; B - Al2O3 (180 µm; C - Al2O3 (110 µm; D - Al2O3 (50 µm. Ceramic rings were fused around the CpTi rods. Specimens were invested and their tensile strength was measured at fracture with a universal testing machine at a crosshead speed of 2.0 mm/min and 200 kgf load cell. Statistical analysis was carried out with analysis of variance and compared using the independent t test (p<0.05. RESULTS: Significant differences were found among all subgroups (p<0.05. The highest and the lowest bond strength means were recorded in subgroups WLC (52.62 MPa and LD (24.02 MPa, respectively. CONCLUSION: Airborne particle abrasion yielded significantly lower bond strength as the Al2O3 particle size decreased. Mechanical retention decreased in the laser-welded specimens, i.e. the metal-ceramic tensile bond strength was lower.

  5. Essential Factors Influencing the Bonding Strength of Cold-Sprayed Aluminum Coatings on Ceramic Substrates

    Science.gov (United States)

    Drehmann, R.; Grund, T.; Lampke, T.; Wielage, B.; Wüstefeld, C.; Motylenko, M.; Rafaja, D.

    2018-02-01

    The present work summarizes the most important results of a research project dealing with the comprehensive investigation of the bonding mechanisms between cold-sprayed Al coatings and various poly- and monocrystalline ceramic substrates (Al2O3, AlN, Si3N4, SiC, MgF2). Due to their exceptional combination of properties, metallized ceramics are gaining more and more importance for a wide variety of applications, especially in electronic engineering. Cold spray provides a quick, flexible, and cost-effective one-step process to apply metallic coatings on ceramic surfaces. However, since most of the existing cold-spray-related publications focus on metallic substrates, only very little is known about the bonding mechanisms acting between cold-sprayed metals and ceramic substrates. In this paper, the essential factors influencing the bonding strength in such composites are identified. Besides mechanical tensile strength testing, a thorough analysis of the coatings and especially the metal/ceramic interfaces was conducted by means of HRTEM, FFT, STEM, EDX, EELS, GAXRD, and EBSD. The influence of substrate material, substrate temperature, and particle size is evaluated. The results suggest that, apart from mechanical interlocking, the adhesion of cold-sprayed metallic coatings on ceramics is based on a complex interplay of different mechanisms such as quasiadiabatic shearing, static recrystallization, and heteroepitaxial growth.

  6. Comparison of porcelain bond strength of different metal frameworks prepared by using conventional and recently introduced fabrication methods.

    Science.gov (United States)

    Kaleli, Necati; Saraç, Duygu

    2017-07-01

    Most studies evaluating dental laser sintering systems have focused on the marginal accuracy of the restorations. However, the bond strength at the metal-ceramic interface is another important factor that affects the survival of restorations, and currently, few studies focus on this aspect. The purpose of this in vitro study was to compare the porcelain bond strength of cobalt-chromium (Co-Cr) metal frameworks prepared by using the conventional lost-wax technique, milling, direct metal laser sintering (DMLS), and laser cusing, a direct process powder-bed system. A total of 96 metal frameworks (n=24 in each group) were prepared by using conventional lost-wax (group C), milling (group M), DMLS (group LS), and direct process powder-bed (group LC) methods according to International Organization for Standardization standard ISO 9693-1. After porcelain application, a 3-point bend test was applied to each specimen by using a universal testing machine. Data were statistically analyzed using 1-way ANOVA and Tukey honest significant difference tests (α=.05). Failure types at the metal-ceramic interfaces were examined using stereomicroscopy. Additionally, 1 specimen from each group was prepared for scanning electron microscopy analysis to evaluate the surface topography of metal frameworks. The mean bond strength was 38.08 ±3.82 MPa for group C, 39.29 ±3.51 MPa for group M, 40.73 ±3.58 MPa for group LS, and 41.24 ±3.75 MPa for group LC. Statistically significant differences were observed among the 4 groups (P=.016). All groups, except for LS, exhibited adhesive and mixed type bond failure. Both of the laser sintering methods were found to be successful in terms of metal-ceramic bond strength. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  7. Amalgam shear bond strength to dentin using different bonding agents.

    Science.gov (United States)

    Vargas, M A; Denehy, G E; Ratananakin, T

    1994-01-01

    This study evaluated the shear bond strength of amalgam to dentin using five different bonding agents: Amalgambond Plus, Optibond, Imperva Dual, All-Bond 2, and Clearfil Liner Bond. Flat dentin surfaces obtained by grinding the occlusal portion of 50 human third molars were used for this study. To contain the amalgam on the tooth surface, cylindrical plastic molds were placed on the dentin and secured with sticky wax. The bonding agents were then applied according to the manufacturers' instructions or light activated and Tytin amalgam was condensed into the plastic molds. The samples were thermocycled and shear bond strengths were determined using an Instron Universal Testing Machine. Analysis by one-way ANOVA indicated significant difference between the five groups (P < 0.05). The bond strength of amalgam to dentin was significantly higher with Amalgambond Plus using the High-Performance Additive than with the other four bonding agents.

  8. Determination of the bonding strength in solid oxide fuel cells’interfaces by Schwickerath crack initiation test

    Czech Academy of Sciences Publication Activity Database

    Boccaccini, D. N.; Ševeček, O.; Frandsen, L. H.; Dlouhý, Ivo; Molin, S.; Charlas, B.; Hjelm, J.; Cannio, M.; Hendriksen, P. V.

    2017-01-01

    Roč. 37, č. 11 (2017), s. 3565-3578 ISSN 0955-2219 Institutional support: RVO:68081723 Keywords : Schwickerath crack-initiation test * Three-point bending test * SOFC interfaces * Metal-ceramic bond strength Subject RIV: JI - Composite Materials OBOR OECD: Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics Impact factor: 3.411, year: 2016 https://apps.webofknowledge.com/full_record.do?product=WOS&search_mode=GeneralSearch&qid=3&SID=S1ftxS2ACYn8QwRNK3P&page=1&doc=1

  9. Comparison of shear bond strength of the stainless steel metallic brackets bonded by three bonding systems

    Directory of Open Access Journals (Sweden)

    Mehdi Ravadgar

    2013-09-01

    Full Text Available Introduction: In orthodontic treatment, it is essential to establish a satisfactory bond between enamel and bracket. After the self-etch primers (SEPs were introduced for the facilitation of bracket bonding in comparison to the conventional etch-and-bond system, multiple studies have been carried out on their shear bond strengths which have yielded different results. This study was aimed at comparing shear bond strengths of the stainless steel metallic brackets bonded by three bonding systems. Methods: In this experimental in vitro study, 60 extracted human maxillary premolar teeth were randomly divided into three equal groups: in the first group, Transbond XT (TBXT light cured composite was bonded with Transbond plus self-etching primer (TPSEP in the second group, TBXT composite was bonded with the conventional method of acid etching and in the third group, the self cured composite Unite TM bonding adhesive was bonded with the conventional method of acid etching. In all the groups, Standard edgewise-022 metallic brackets (American Orthodontics, Sheboygan, USA were used. Twenty-four hours after the completion of thermocycling, shear bond strength of brackets was measured by Universal Testing Machine (Zwick. In order to compare the shear bond strengths of the groups, the variance analysis test (ANOVA was adopted and p≤0.05 was considered as a significant level. Results: Based on megapascal, the average shear bond strength for the first, second, and third groups was 8.27±1.9, 9.78±2, and 8.92±2.5, respectively. There was no significant difference in the shear bond strength of the groups. Conclusions: Since TPSEP shear bond strength is approximately at the level of the conventional method of acid etching and within the desirable range for orthodontic brackets shear bond strength, applying TPSEP can serve as a substitute for the conventional method of etch and bond, particularly in orthodontic operations.

  10. Comparison of shear bond strength of the stainless steel metallic brackets bonded by three bonding systems

    Directory of Open Access Journals (Sweden)

    Mehdi Ravadgar

    2013-09-01

    Full Text Available Introduction: In orthodontic treatment, it is essential to establish a satisfactory bond between enamel and bracket. After the self-etch primers (SEPs were introduced for the facilitation of bracket bonding in comparison to the conventional etch-and-bond system, multiple studies have been carried out on their shear bond strengths which have yielded different results. This study was aimed at comparing shear bond strengths of the stainless steel metallic brackets bonded by three bonding systems. Methods: In this experimental in vitro study, 60 extracted human maxillary premolar teeth were randomly divided into three equal groups: in the first group, Transbond XT (TBXT light cured composite was bonded with Transbond plus self-etching primer (TPSEP; in the second group, TBXT composite was bonded with the conventional method of acid etching; and in the third group, the self cured composite Unite TM bonding adhesive was bonded with the conventional method of acid etching. In all the groups, Standard edgewise-022 metallic brackets (American Orthodontics, Sheboygan, USA were used. Twenty-four hours after the completion of thermocycling, shear bond strength of brackets was measured by Universal Testing Machine (Zwick. In order to compare the shear bond strengths of the groups, the variance analysis test (ANOVA was adopted and p≤0.05 was considered as a significant level. Results: Based on megapascal, the average shear bond strength for the first, second, and third groups was 8.27±1.9, 9.78±2, and 8.92±2.5, respectively. There was no significant difference in the shear bond strength of the groups. Conclusions: Since TPSEP shear bond strength is approximately at the level of the conventional method of acid etching and within the desirable range for orthodontic brackets shear bond strength, applying TPSEP can serve as a substitute for the conventional method of etch and bond, particularly in orthodontic operations.

  11. Microtensile bond strength of enamel after bleaching.

    Science.gov (United States)

    Lago, Andrea Dias Neves; Garone-Netto, Narciso

    2013-01-01

    To evaluate the bond strength of a composite resin to the bovine enamel bleached with 35% hydrogen peroxide. It was used an etching-and-rinse adhesive system employed immediately, 7 and 14 days after the bleaching. Twenty bovine teeth were randomly distributed into 4 groups (n = 5), 3 experimental and 1 control. G1: Unbleached + restoration 14 days after storage in artificial saliva (control); G2: Bleached + restoration immediately after bleaching; G3: Bleached + restoration 7 days after bleaching; G4: Bleached + restoration 14 days after bleaching. Their buccal enamel surfaces were flattened, and a 25 mm² (5 × 5 mm) area from each one of these regions was outlined so as to standardize the experimental region. Universal hybrid composite resin Filtek™Z350 was inserted into four layers of 1 mm each and photo-activated. The bond strength was quantitatively evaluated by a microtensile test (1.0 mm/min) 24 h after the restorative procedures. The failure mode was assessed through scanning electron microscopy (SEM). There was a significant reduction in the bond strength of the restored teeth immediately after the bleaching (G2). There were no significant differences in enamel bond strength between groups G1, G3, and G4. There was a predominance of adhesive and mixed (cohesive + adhesive) failure in all groups. The 7-day-period after the end of the bleaching with 35% hydrogen peroxide was enough to achieve the appropriate values of bond strength to the enamel.

  12. Shear Bond Strength of Orthodontic Brackets Bonded to Zirconium Crowns.

    Science.gov (United States)

    Mehmeti, Blerim; Azizi, Bleron; Kelmendi, Jeta; Iljazi-Shahiqi, Donika; Alar, Željko; Anić-Milošević, Sandra

    2017-06-01

    An increasing demand for esthetic restorations has resulted in an increased use of all-ceramic restorations, such as zirconium. However, one of the challenges the orthodontist must be willing to face is how to increase bond strength between the brackets and various ceramic restorations.Bond strength can beaffected bybracket type, by the material that bracketsaremade of, and their base surface design or retention mode. ​: A im: of this study was to perform a comparative analysis of the shear bond strength (SBS) of metallic and ceramic orthodontic brackets bonded to all-zirconium ceramic surfaces used for prosthetic restorations, and also to evaluate the fracture mode of these two types of orthodontic brackets. Twenty samples/semi-crowns of all-zirconium ceramic, on which orthodontic brackets were bonded, 10 metallic and 10 ceramic polycrystalline brackets, were prepared for this research. SBS has been testedby Universal Testing Machine, with a load applied using a knife edged rod moving at a fixed rate of 1 mm/min, until failure occurred. The force required to debond the brackets was recorded in Newton, then SBS was calculated to MPa. In addition, the samples were analyzed using a digital camera magnifier to determine Adhesive Remnant Index (ARI). Statistical data were processed using t-test, and the level of significance was set at α = 0.05. Higher shear bond strength values were observed in metallic brackets bonded to zirconium crowns compared tothoseof ceramic brackets, with a significant difference. During the test, two of the ceramic brackets were partially or totally damaged. Metallic brackets, compared to ceramic polycrystalline brackets, seemed tocreate stronger adhesion with all-zirconium surfaces due to their better retention mode. Also, ceramic brackets showed higher fragility during debonding.

  13. Production of metal and metal-ceramic coatings on D-Gun Ob

    International Nuclear Information System (INIS)

    Gavrilenko, T.P.; Nikolaev, Y.A.; Ulianitsky, V.Y.

    1995-01-01

    Optimization of the detonation spraying process has been made for the production of metal and metal-ceramics coatings with the D-Gun Ob. Owing to the ability of Ob to work with several fuels and an inert diluent simultaneously, variation of detonation regimes in a wide range is possible, and because of localized powder injection in the D-Gun barrel, high uniformity of parameters of powder particles is achieved. The best conditions for particle heating and acceleration were calculated with the help of mathematical simulation, and the corresponding regimes were realized on D-Gun Ob. High-quality aluminum, copper, nickel, and nickel-chromium-silicon-carbon-boron alloy coatings were produced by using only propane fuel. Chromium carbide with nickel and tungsten carbide with cobalt coatings were produced with addition of acetylene. Optimal efficiency and high bonding strength were achieved for all powders. Data on microhardness, bonding strength, and efficiency are presented

  14. Metal-ceramic joint assembly

    Science.gov (United States)

    Li, Jian

    2002-01-01

    A metal-ceramic joint assembly in which a brazing alloy is situated between metallic and ceramic members. The metallic member is either an aluminum-containing stainless steel, a high chromium-content ferritic stainless steel or an iron nickel alloy with a corrosion protection coating. The brazing alloy, in turn, is either an Au-based or Ni-based alloy with a brazing temperature in the range of 9500 to 1200.degree. C.

  15. Mullite/Mo interfaces formed by Intrusion bonding

    Energy Technology Data Exchange (ETDEWEB)

    Bartolome, Jose F.; Diaz, Marcos; Moya, Jose S.; Saiz, Eduardo; Tomsia, Antoni P.

    2003-04-30

    The microstructure and strength of Mo/mullite interfaces formed by diffusion bonding at 1650 C has been analyzed. Interfacial metal-ceramic interlocking contributes to flexural strength of approx. 140 MPa as measured by 3 point bending. Saturation of mullite with MoO2 does not affect the interfacial strength.

  16. Mullite/Mo interfaces formed by Intrusion bonding

    OpenAIRE

    Bartolome, Jose F.; Diaz, Marcos; Moya, Jose S.; Saiz, Eduardo; Tomsia, Antoni P.

    2003-01-01

    The microstructure and strength of Mo/mullite interfaces formed by diffusion bonding at 1650oC has been analyzed. Interfacial metal-ceramic interlocking contributes to flexural strength of approx. 140 MPa as measured by 3 point bending. Saturation of mullite with MoO2 does not affect the interfacial strength.

  17. Microtensile bond strength of enamel after bleaching

    Directory of Open Access Journals (Sweden)

    Andréa Dias Neves Lago

    2013-01-01

    Full Text Available Objective: To evaluate the bond strength of a composite resin to the bovine enamel bleached with 35% hydrogen peroxide. It was used an etching-and-rinse adhesive system employed immediately, 7 and 14 days after the bleaching. Materials and Methods: Twenty bovine teeth were randomly distributed into 4 groups (n = 5, 3 experimental and 1 control. G1: Unbleached + restoration 14 days after storage in artificial saliva (control; G2: Bleached + restoration immediately after bleaching; G3: Bleached + restoration 7 days after bleaching; G4: Bleached + restoration 14 days after bleaching. Their buccal enamel surfaces were flattened, and a 25 mm² (5 × 5 mm area from each one of these regions was outlined so as to standardize the experimental region. Universal hybrid composite resin Filtek™Z350 was inserted into four layers of 1 mm each and photo-activated. The bond strength was quantitatively evaluated by a microtensile test (1.0 mm/min 24 h after the restorative procedures. The failure mode was assessed through scanning electron microscopy (SEM. Results: There was a significant reduction in the bond strength of the restored teeth immediately after the bleaching (G2. There were no significant differences in enamel bond strength between groups G1, G3, and G4. There was a predominance of adhesive and mixed (cohesive + adhesive failure in all groups. Conclusion: The 7-day-period after the end of the bleaching with 35% hydrogen peroxide was enough to achieve the appropriate values of bond strength to the enamel.

  18. Comparison of the bond strength of ceramics to Co-Cr alloys made by casting and selective laser melting.

    Science.gov (United States)

    Lawaf, Shirin; Nasermostofi, Shahbaz; Afradeh, Mahtasadat; Azizi, Arash

    2017-02-01

    Considering the importance of metal-ceramic bond, the present study aimed to compare the bond strength of ceramics to cobalt-chrome (Co-Cr) alloys made by casting and selective laser melting (SLM). In this in-vitro experimental study, two sample groups were prepared, with one group comprising of 10 Co-Cr metal frameworks fabricated by SLM method and the other of 10 Co-Cr metal frameworks fabricated by lost wax cast method with the dimensions of 0.5 × 3 × 25 mm (following ISO standard 9693). Porcelain with the thickness of 1.1 mm was applied on a 3 × 8-mm central rectangular area of each sample. Afterwards, bond strengths of the samples were assessed with a Universal Testing Machine. Statistical analysis was performed with Kolmogorov-Smirnov test and T-test. Bond strength in the conventionally cast group equaled 74.94 ± 16.06 MPa, while in SLM group, it equaled 69.02 ± 5.77 MPa. The difference was not statistically significant ( P ≤ .05). The results indicated that the bond strengths between ceramic and Co-Cr alloys made by casting and SLM methods were not statistically different.

  19. Enamel Bond Strength of New Universal Adhesive Bonding Agents.

    Science.gov (United States)

    McLean, D E; Meyers, E J; Guillory, V L; Vandewalle, K S

    2015-01-01

    Universal bonding agents have been introduced for use as self-etch or etch-and-rinse adhesives depending on the dental substrate and clinician's preference. The purpose of this study was to evaluate the shear bond strength (SBS) of composite to enamel using universal adhesives compared to a self-etch adhesive when applied in self-etch and etch-and-rinse modes over time. Extracted human third molars were used to create 120 enamel specimens. The specimens were ground flat and randomly divided into three groups: two universal adhesives and one self-etch adhesive. Each group was then subdivided, with half the specimens bonded in self-etch mode and half in etch-and-rinse mode. The adhesives were applied as per manufacturers' instructions, and composite was bonded using a standardized mold and cured incrementally. The groups were further divided into two subgroups with 10 specimens each. One subgroup was stored for 24 hours and the second for six months in 37°C distilled water and tested in shear. Failure mode was also determined for each specimen. A three-way analysis of variance (ANOVA) found a significant difference between groups based on bonding agent (p0.05). Clearfil SE in etch-and-rinse and self-etch modes had more mixed fractures than either universal adhesive in either mode. Etching enamel significantly increased the SBS of composite to enamel. Clearfil SE had significantly greater bond strength to enamel than either universal adhesive, which were not significantly different from each other.

  20. Evaluation of the mechanical properties and porcelain bond strength of cobalt-chromium dental alloy fabricated by selective laser melting.

    Science.gov (United States)

    Wu, Lin; Zhu, Haiting; Gai, Xiuying; Wang, Yanyan

    2014-01-01

    Limited information is available regarding the microstructure and mechanical properties of dental alloy fabricated by selective laser melting (SLM). The purpose of this study was to evaluate the mechanical properties of a cobalt-chromium (Co-Cr) dental alloy fabricated by SLM and to determine the correlation between its microstructure and mechanical properties and its porcelain bond strength. Five metal specimens and 10 metal ceramic specimens were fabricated to evaluate the mechanical properties of SLM Co-Cr dental alloy (SLM alloy) with a tensile test and its porcelain bond strength with a 3-point bending test. The relevant properties of the SLM alloy were compared with those of the currently used Co-Cr dental alloy fabricated with conventional cast technology (cast alloy). The Student t test was used to compare the results of the SLM alloy and the cast alloy (α=.05). The microstructure of the SLM alloy was analyzed with a metallographic microscope; the metal ceramic interface of the SLM porcelain bonded alloy was studied with scanning electron microscopy, energy dispersive x-ray spectroscopy, and an electron probe microanalyzer. Both the mean (standard deviation) yield strength (884.37 ± 8.96 MPa) and tensile strength (1307.50 ±10.65 MPa) of the SLM alloy were notably higher than yield strength (568.10 ± 30.94 MPa) and tensile strength (758.73 ± 25.85 MPa) of the currently used cast alloy, and the differences were significant (P.05). Microstructure analysis suggested that the SLM alloy had a dense and obviously orientated microstructure, which led to excellent mechanical properties. Analysis from scanning electron microscopy, energy dispersive x-ray spectroscopy, and the electron probe microanalyzer indicated that the SLM alloy had an intermediate layer with elemental interpenetration between the alloy and the porcelain, which resulted in an improved bonding interface. Compared with the currently used cast alloy, SLM alloy possessed improved mechanical

  1. Noble metal alloys for metal-ceramic restorations.

    Science.gov (United States)

    Anusavice, K J

    1985-10-01

    A review of the comparative characteristics and properties of noble metal alloys used for metal-ceramic restorations has been presented. Selection of an alloy for one's practice should be based on long-term clinical data, physical properties, esthetic potential, and laboratory data on metal-ceramic bond strength and thermal compatibility with commercial dental porcelains. Although gold-based alloys, such as the Au-Pt-Pd, Au-Pd-Ag, and Au-Pd classes, may appear to be costly compared with the palladium-based alloys, they have clearly established their clinical integrity and acceptability over an extended period of time. Other than the relatively low sag resistance of the high gold-low silver content alloys and the potential thermal incompatibility with some commercial porcelain products, few clinical failures have been observed. The palladium-based alloys are less costly than the gold-based alloys. Palladium-silver alloys require extra precautions to minimize porcelain discoloration. Palladium-copper and palladium-cobalt alloys may also cause porcelain discoloration, as copper and cobalt are used as colorants in glasses. The palladium-cobalt alloys are least susceptible to high-temperature creep compared with all classes of noble metals. Nevertheless, insufficient clinical data exist to advocate the general use of the palladium-copper and palladium-cobalt alloys at the present time. One should base the selection and use of these alloys in part on their ability to meet the requirements of the ADA Acceptance Program. A list of acceptable or provisionally acceptable alloys is available from the American Dental Association and is published annually in the Journal of the American Dental Association. Dentists have the legal and ethical responsibility for selection of alloys used for cast restorations. This responsibility should not be delegated to the dental laboratory technician. It is advisable to discuss the criteria for selection of an alloy with the technician and the

  2. Determine bond strength by ultrasonic measurement

    International Nuclear Information System (INIS)

    Brown, C.M.

    1978-01-01

    Application of ultrasonic methods for the evaluation and measurement of bond strength has been the object of numerous investigations in the last fifteen years. Some investigators have reported good success (in limited application) while others have experienced dismal failure. One problem common to all investigations was the difficulty in extracting and isolating the many components which comprise the ultrasonic signal reflected from a bonded interface. Part of this problem was due to manually extracting individual parameters from large volumes of raw data. However, with the vast technology now available in the field of signal analysis and computerized data processing, it is feasible to isolate and analyze individual parameters within the ultrasonic signal for great volumes of raw data

  3. Enamel and dentin bond strength following gaseous ozone application.

    Science.gov (United States)

    Cadenaro, Milena; Delise, Chiara; Antoniollo, Francesca; Navarra, Ottavia Chiara; Di Lenarda, Roberto; Breschi, Lorenzo

    2009-08-01

    To evaluate the effects of gaseous ozone application on enamel and dentin bond strength produced by two self-etching adhesive systems. The shear bond strength test was conducted to assess adhesion on enamel (protocol 1), while the microtensile bond strength test was performed on dentin (protocol 2). Protocol 1: 96 bovine incisors were randomly divided into 4 groups, and enamel surfaces were bonded in accordance with the following treatments: (1E) ozone + Clearfil Protect Bond; (2E) Clearfil Protect Bond (control); (3E) ozone + Xeno III; (4E) Xeno III (control). Ozone gas was applied for 80 s. Shear bond strength was measured with a universal testing machine. Protocol 2: 40 noncarious human molars were selected. Middle/deep dentin was exposed and bonded in accordance with the following treatments: (1D) ozone+Clearfil Protect Bond; (2D) Clearfil Protect Bond (control); (3D) ozone+Xeno III (4D) Xeno III (control). Four-mm-thick buildups were built on the adhesives, then specimens were sectioned in accordance with the nontrimming technique. Specimens were stressed until failure occurred, and failure modes were analyzed. Shear bond and microtensile bond strength data were analyzed using two-way ANOVA and Tukey's post-hoc test. No statistical differences were found between ozone treated specimens and controls, neither on enamel nor on dentin irrespective of the tested adhesive. Clearfil Protect Bond showed higher bond strength to enamel than Xeno III, irrespective of the ozone treatment (p enamel and dentin bond strength.

  4. Effect of simulated pulpal pressure on composite bond strength to ...

    African Journals Online (AJOL)

    Statistical significance was determined by T-test (p < 0.05). There was a statistically significant difference in the mean microtensile bond strengths between the groups (p < 0.0005). Simulated pulpal pressure had a negative effect on microtensile bond strength of laser ablated dentin when Single Bond adhesive system was ...

  5. Bond strength of compomers to dentin using acidic primers.

    Science.gov (United States)

    Tate, W H; You, C; Powers, J M

    1999-10-01

    To determine the in vitro bond strengths of seven compomer/bonding agent restorative systems to human dentin. Seven compomer/bonding agents were bonded to human dentin, stored in water at 37 degrees C for 24 hours, and debonded in tension. Bonding conditions were with and without phosphoric acid etching, with and without the use of combined primer/bonding agents, and under moist and wet bond interfaces. Without phosphoric acid etching, F2000/F2000 Compomer Primer/Adhesive and F2000/Single Bond Dental Adhesive System were less sensitive to dentin wetness. With moist dentin, bond strengths of Dyract/Prime & Bond 2.1, Dyract AP/Prime & Bond 2.1, Hytac/OSB light-curing, one-component bonding agent, F2000/Single Bond, and Freedom/STAE single component light-cured dentin/enamel adhesive system, were improved with phosphoric acid etching. Also, with moist dentin, the bond strength of F2000/F2000 Compomer Primer/Adhesive in the 3M Clicker dispensing system was higher without phosphoric acid etching, whereas bonds of Compoglass/Syntac Single-component were not affected by phosphoric acid etching. Bonding did not occur without primer/bonding agent, regardless of surface condition or use of phosphoric acid etching.

  6. Comparative evaluation of shear bond strength of metallic brackets bonded with two different bonding agents under dry conditions and with saliva contamination

    Directory of Open Access Journals (Sweden)

    Mashallah Khanehmasjedi

    2017-02-01

    Conclusion: Application of Single Bond and Assure bonding agents resulted in adequate bond strength of brackets to tooth structures. Contamination with saliva significantly decreased the bond strength of Assure bonding agent compared with dry conditions.

  7. A Comparison of Shear Bond Strength of Two Different Techniques with that of Initially Bonded Brackets

    Directory of Open Access Journals (Sweden)

    Abdolhamid Zafarmand

    2014-01-01

    Conclusion: However, there was no significant difference in the shear strength responses of three groups. The results of the study showed that both techniques of rebonding of failed brackets can provide effective bonding strengths similar to the primary strength.

  8. Bond strength and microleakage of current dentin adhesives.

    Science.gov (United States)

    Fortin, D; Swift, E J; Denehy, G E; Reinhardt, J W

    1994-07-01

    The purpose of this in vitro study was to evaluate shear bond strengths and microleakage of seven current-generation dentin adhesive systems. Standard box-type Class V cavity preparations were made at the cemento-enamel junction on the buccal surfaces of eighty extracted human molars. These preparations were restored using a microfill composite following application of either All-Bond 2 (Bisco), Clearfil Liner Bond (Kuraray), Gluma 2000 (Miles), Imperva Bond (Shofu), OptiBond (Kerr), Prisma Universal Bond 3 (Caulk), Scotchbond Multi-Purpose (3M), or Scotchbond Dual-Cure (3M) (control). Lingual dentin of these same teeth was exposed and polished to 600-grit. Adhesives were applied and composite was bonded to the dentin using a gelatin capsule technique. Specimens were thermocycled 500 times. Shear bond strengths were determined using a universal testing machine, and microleakage was evaluated using a standard silver nitrate staining technique. Clearfill Liner Bond and OptiBond, adhesive systems that include low-viscosity, low-modulus intermediate resins, had the highest shear bond strengths (13.3 +/- 2.3 MPa and 12.9 +/- 1.5 MPa, respectively). Along with Prisma Universal Bond 3, they also had the least microleakage at dentin margins of Class V restorations. No statistically significant correlation between shear bond strength and microleakage was observed in this study. Adhesive systems that include a low-viscosity intermediate resin produced the high bond strengths and low microleakage. Similarly, two materials with bond strengths in the intermediate range had significantly increased microleakage, and one material with a bond strength in the low end of the spectrum exhibited microleakage that was statistically greater. Thus, despite the lack of statistical correlation, there were observable trends.

  9. Metal-ceramic materials. Study and prediction of effective mechanical properties

    International Nuclear Information System (INIS)

    Karakulov, Valerii V.; Smolin, Igor Yu.

    2016-01-01

    Mechanical behavior of stochastic metal-ceramic composite materials was numerically simulated on mesoscopic scale level. Deformation of mesoscopic volumes of composites, whose structure consists of a metal matrix and randomly distributed ceramic inclusions, was numerically simulated. The results of the numerical simulation were used for evaluation of the effective elastic and strength properties of metal-ceramic materials with different parameters of the structure. The values of the effective mechanical properties of investigated materials were obtained, and the character of the dependence of the effective elastic and strength properties on the structure parameters of composites was determined.

  10. Effects of surface treatments on bond strength of dental Ti-20Cr and Ti-10Zr alloys to porcelain

    International Nuclear Information System (INIS)

    Lin, Hsi-Chen; Wu, Shih-Ching; Ho, Wen-Fu; Huang, Ling-Hsiu; Hsu, Hsueh-Chuan

    2010-01-01

    The purpose of this study was to investigate the effect of surface treatments, including sandblasting and grinding, on the bond strength between a low-fusing porcelain and c.p. Ti, Ti-20Cr and Ti-10Zr alloys. The surface treatments were divided into 2 groups. Grinding surface treatment was applied to the first group, which served as the control, and sandblasting was applied to the second group. After treatment, low-fusing porcelain (Titankeramik) was fired onto the surface of the specimens. A universal testing machine was used to perform a 3-point bending test. The metal-ceramic interfaces were subjected to scanning electron microscopic analysis. Of the sandblasted samples, the debonding test showed that Ti-20Cr alloy had the strongest (31.50 MPa) titanium-ceramic bond (p < 005), followed by c.p. Ti (29.4 MPa) and Ti-10Zr (24.3 MPa). Of the grinded samples, Ti-20Cr alloy showed 27.3 MPa titanium-ceramic bond (p < 005), followed by c.p. Ti (14.3 MPa) and Ti-10Zr (failure). The SEM micrographs of the metal surface after debonding showed residual porcelain retained on all samples. On the whole, sandblasting surface treatment appears to have had a more beneficial effect on the Ti-ceramic bond strength than grinding surface treatment. Furthermore, surface treatment of Ti-20Cr with either grinding or sandblasting resulted in adequate bond strength, which exceeded the lower limit value in the ISO 9693 standard (25 MPa).

  11. In Vitro Comparison of the Bond Strength between Ceramic Repair Systems and Ceramic Materials and Evaluation of the Wettability.

    Science.gov (United States)

    Kocaağaoğlu, Hasan; Manav, Taha; Albayrak, Haydar

    2017-04-01

    When fracture of an all-ceramic restoration occurs, it can be necessary to repair without removing the restoration. Although there are many studies about the repair of metal-ceramic restorations, there are few about all-ceramic restorations. The aim of this study was to evaluate the shear bond strength between ceramic repair systems and esthetic core materials and to evaluate the wettability of all-ceramic core materials. Disk-like specimens (N = 90) made of three dental ceramic infrastructure materials (zirconia ceramic, alumina ceramic, glass ceramic) were polished with silicon carbide paper, prepared for bonding (abrasion with 30 μm diamond rotary cutting instrument). Thirty specimens of each infrastructure were obtained. Each infrastructure group was divided into three subgroups; they were bonded using 3 repair systems: Bisco Intraoral Repair Kit, Cimara & Cimara Zircon Repair System, and Clearfil Repair System. After 1200 thermocycles, shear bond strength was measured in a universal testing machine at a 0.5 mm/min crosshead speed. In addition, the contact angle values of the infrastructures after surface treatments were examined for wettability. Data were analyzed by using ANOVA and Tukey post hoc tests. Although there were no significant differences among the repair systems (p > 0.05) in the glass ceramic and zirconia groups, a significant difference was found among the repair systems in alumina infrastructure (p 0.05); however, a statistically significant difference was found among the repair systems (p < 0.05). No difference was found among the infrastructures and repair systems in terms of contact angle values. Cimara & Cimara Zircon Repair System had higher bond strength values than the other repair systems. Although no difference was found among the infrastructures and repair systems, contact wettability angle was decreased by surface treatments compared with polished surfaces. © 2015 by the American College of Prosthodontists.

  12. Evaluation of microtensile and tensile bond strength tests ...

    African Journals Online (AJOL)

    2015-11-03

    Nov 3, 2015 ... Bond strength tests and Er,Cr:YSGG laser frequency. 586 ... power, 90% air pressure, 75% water pressure, 45 s irradiation ..... geometry on the measurement of the tensile bond strength to dentin. J Dent ... Bur‑cut enamel and.

  13. The effect of air thinning on dentin adhesive bond strength.

    Science.gov (United States)

    Hilton, T J; Schwartz, R S

    1995-01-01

    The purpose of this study was to determine if air thinning three dentin adhesives would affect bond strength to dentin. Ninety human molars were mounted in acrylic and the occlusal surfaces ground to expose a flat dentin surface. Thirty teeth were randomly assigned to one of the following dentin bonding agent/composite combinations: A) Universal Bond 3/TPH (Caulk), B) All-Bond 2/Bis-Fil-P (Bisco), and C) Scotchbond Multi-Purpose/Z-100 (3m). The primers were applied following the manufacturers' instructions. The adhesives were applied by two methods. A thin layer of adhesive was applied with a brush to 15 specimens in each group and light cured. Adhesive was brushed on to the remaining 15 teeth in the group, air thinned for 3 seconds, and then polymerized. The appropriate composite was applied in 2 mm increments and light cured utilizing a 5 mm-in-diameter split Teflon mold. Following 3 months of water storage, all groups were shear tested to failure on an Instron Universal Testing Machine. Bond strength was significantly higher in all groups when the dentin bonding agent was painted on without being air thinned. Scotchbond Multi-Purpose had significantly higher bond strength than All-Bond 2, which had significantly higher bond strength than Universal Bond 3.

  14. Strength of Al and Al-Mg/alumina bonds prepared using ultrahigh vacuum diffusion bonding

    International Nuclear Information System (INIS)

    King, W.E.; Campbell, G.H.; Wien, W.L.; Stoner, S.L.

    1994-01-01

    The authors have measured the cross-breaking strength of Al and Al-Mg alloys bonded with alumina. Diffusion bonding of Al and Al-Mg alloys requires significantly more bonding time than previously thought to obtain complete bonding. In contrast to previous diffusion bonding studies, fracture morphologies are similar to those obtained in bonds formed by liquid phase reaction; i.e., bonds are as strong or stronger than the ceramic; and fracture tends to propagate in the metal for pure Al and near the interface in the ceramic for the alloys. There are indications that the fracture morphology depends on Mg content and therefore on plasticity in the metal

  15. Effects of etching time on enamel bond strengths.

    Science.gov (United States)

    Triolo, P T; Swift, E J; Mudgil, A; Levine, A

    1993-12-01

    This study evaluated the effects of etching time on bond strengths of composite to enamel. Proximal surfaces of extracted molars were etched with either a conventional etchant (35% phosphoric acid) or one of two dentin/enamel conditioners, 10% maleic acid (Scotchbond Multi-Purpose Etchant), or a solution of oxalic acid, aluminum nitrate, and glycine (Gluma 1 & 2 Conditioner). Each agent was applied for 15, 30, or 60 seconds. Specimens etched with 35% phosphoric acid had the highest mean bond strengths at each etching time. At the manufacturer's recommended application times, the other two agents gave significantly lower shear bond strengths than phosphoric acid.

  16. Bond strength tests between silicon wafers and duran tubes (fusion bonded fluidic interconnects)

    NARCIS (Netherlands)

    Fazal, I.; Berenschot, Johan W.; de Boer, J.H.; Jansen, Henricus V.; Elwenspoek, Michael Curt

    2005-01-01

    The fusion bond strength of glass tubes with standard silicon wafers is presented. Experiments with plain silicon wafers and those coated with silicon oxide and silicon nitride are presented. Results obtained are discussed in terms of homogeneity and strength of fusion bond. High pressure testing

  17. Comparison of Shear Bond Strengths of three resin systems for a Base Metal Alloy bonded to

    Directory of Open Access Journals (Sweden)

    Jlali H

    1999-12-01

    Full Text Available Resin-bonded fixed partial dentures (F.P.D can be used for conservative treatment of partially edentulous"npatients. There are numerous studies regarding the strength of resin composite bond to base meta! alloys. Shear bond"nstrength of three resin systems were invistigated. In this study these systems consisted of: Panavia Ex, Mirage FLC and"nMarathon V. Thirty base metal specimens were prepared from rexillium III alloy and divided into three groups. Then each"ngroup was bonded to enamel of human extracted molar teeth with these systems. All of specimens were stored in water at"n37ac for 48 hours. A shear force was applied to each specimen by the instron universal testing machine. A statistical"nevaluation of the data using one-way analysis of variance showed that there was highly significant difference (P<0.01"nbetween the bond strengths of these three groups."nThe base metal specimens bonded with panavia Ex luting agent, exhibited the highest mean bond strength. Shear bond"nstrength of the specimens bonded to enamel with Mirage F1C showed lower bond strenght than panavia EX. However, the"nlowest bond strength was obtained by the specimens bonded with Marathon V.

  18. Strength of Bond Covenants and Bond Assessment Framework

    Directory of Open Access Journals (Sweden)

    Noel Yahanpath

    2012-06-01

    Full Text Available We examine bond covenants of 29 New Zealand bond issues between 2001 and 2007.Results from the study indicate that protection provided for bondholders is weak and limited.On average, only 2-3 types of covenants are embedded with the issues and only 27% of thesecovenants provide full protection to the bondholders. However, bondholders are not compensated for taking the additional risk. We propose an alternative assessment framework that directly assesses the level of protection offered to bondholders. We calculate thecovenant quality score for the issues and classify them into four levels of protection: very high protection, moderate, low and very low. Recent legislative changes will go some way towards improving investor protection and confidence, but the effect is yet to be seen. This proposed scoring framework can be used by potential investors to complement the traditional credit ratings when making their investment decisions.

  19. Evaluation of Calcium Silicate Cement Bond Strength after Using ...

    African Journals Online (AJOL)

    2018-01-24

    Jan 24, 2018 ... (chloroform, Endosolv E, orange oil, and eucalyptol) on the push‑out bond strength of calcium ... rotary files, lasers, heating apparatuses, or ultrasonic instruments. .... essential factor for the success of endodontic treatments.

  20. The effect of different surface treatments on the shear bond strength of luting cements to titanium.

    Science.gov (United States)

    Abi-Rached, Filipe de Oliveira; Fonseca, Renata Garcia; Haneda, Isabella Gagliardi; de Almeida-Júnior, Antonio Alves; Adabo, Gelson Luis

    2012-12-01

    Although titanium presents attractive physical and mechanical properties, there is a need for improving the bond at the titanium/luting cement interface for the longevity of metal ceramic restorations. The purpose of this study was to evaluate the effect of surface treatments on the shear bond strength (SBS) of resin-modified glass ionomer and resin cements to commercially pure titanium (CP Ti). Two hundred and forty CP Ti cast disks (9.0 × 3.0 mm) were divided into 8 surface treatment groups (n=30): 1) 50 µm Al(2)O(3) particles; 2) 120 µm Al(2)O(3) particles; 3) 250 µm Al(2)O(3) particles; 4) 50 µm Al(2)O(3) particles + silane (RelyX Ceramic Primer); 5) 120 µm Al(2)O(3) particles + silane; 6) 250 µm Al(2)O(3) particles + silane; 7) 30 µm silica-modified Al(2)O(3) particles (Cojet Sand) + silane; and 8) 120 µm Al(2)O(3) particles, followed by 110 µm silica-modified Al(2)O(3) particles (Rocatec). The luting cements 1) RelyX Luting 2; 2) RelyX ARC; or 3) RelyX U100 were applied to the treated CP Ti surfaces (n=10). Shear bond strength (SBS) was tested after thermal cycling (5000 cycles, 5°C to 55°C). Data were analyzed by 2-way analysis of variance (ANOVA) and the Tukey HSD post hoc test (α=.05). Failure mode was determined with a stereomicroscope (×20). The surface treatments, cements, and their interaction significantly affected the SBS (Pbehavior for all surface treatments. For both cements, only the group abraded with 50 μm Al(2)O(3) particles had lower SBS than the other groups (P<.05). For RelyX ARC, regardless of silane application, abrasion with 50 μm Al(2)O(3) particles resulted in significantly lower SBS than abrasion with 120 μm and 250 μm particles, which exhibited statistically similar SBS values to each other. Rocatec + silane promoted the highest SBS for RelyX ARC. RelyX U100 presented the highest SBS mean values (P<.001). All groups showed a predominance of adhesive failure mode. The adhesive capability of RelyX Luting 2 and RelyX U

  1. Evaluation of microtensile and tensile bond strength tests ...

    African Journals Online (AJOL)

    Objectives: The aim of the present study was to compare two different bond strength test methods (tensile and microtensile) in investing the influence of erbium, chromium: yttrium‑scandium‑gallium‑garnet (Er, Cr: YSGG) laser pulse frequency on resin‑enamel bonding. Materials and Methods: One‑hundred and twenty‑five ...

  2. Shear bond strength of metallic brackets: influence of saliva contamination

    Directory of Open Access Journals (Sweden)

    Luciana Borges Retamoso

    2009-06-01

    Full Text Available OBJECTIVE: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III on orthodontic metallic brackets bonded to human enamel. MATERIAL AND METHODS: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer's instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000 running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91 was significantly higher than that of AS (8.58±1.73 and XS (10.39±4.06 groups (p<0.05. Regarding the bond failure pattern, TS group had significantly higher scores of no adhesive remaining on the tooth in the bonding area than other groups considering the adhesive remnant index (ARI used to evaluate the amount of adhesive left on the enamel. CONCLUSIONS: Saliva contamination showed little influence on the 24-h shear bond strength of orthodontic brackets.

  3. Effects of blood contamination on resin-resin bond strength.

    Science.gov (United States)

    Eiriksson, Sigurdur O; Pereira, Patricia N R; Swift, Edward J; Heymann, Harald O; Sigurdsson, Asgeir

    2004-02-01

    Incremental placement and curing of resin composites has been recommended. However, this requires longer operating time, and therefore, increased risk of contamination. The purpose of this study was to evaluate the effects of blood contamination on microtensile bond strengths (microTBS) between resin interfaces and to determine the best decontamination method to re-establish the original resin-resin bond strength. The top surfaces of 64, 4-mm composite blocks (Z-250, Renew, APX, Pertac II) were untreated as the control, or were treated as follows: blood applied and dried on the surface (Treatment 1), blood applied, rinsed, dried (Treatment 2), blood applied, rinsed, and an adhesive applied (Single Bond, One-Step, Clearfil SE, Prompt L-Pop) (Treatment 3). Fresh composite was applied and light-cured in 2-mm increments. After 24 h storage in water, the specimens were sectioned into 0.7-mm thick slabs, trimmed to a cross-sectional area of 1 mm(2), and loaded to failure at a crosshead speed of 1 mm/min using an Instron universal testing machine. Data were analyzed using two-way ANOVA and Fisher's PLSD test (pcontamination resulted in resin-resin bond strengths of only 1.0-13.1 MPa. Rinsing raised bond strengths to over 40 MPa for each material. Use of an adhesive further increased bond strengths except for Pertac II. Rinsing blood from contaminated surfaces increases the resin-resin bond strength significantly and the application of an appropriate adhesive increases the bond strength to control levels.

  4. Bond strength investigation of two shot moulded polymer

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul

    This report on the project “Bond strength investigation of two shot moulded polymers” has been submitted for fulfilling the requirements for the course “Experimental Plastic Technology – 42234” at IPL-DTU. Two shot moulding is a classic manufacturing process to combine two different polymers...... in a single product and it is getting more and more importance day by day. One of the biggest challenges of two shot moulding is to achieve a reasonably good bonding between two polymers. The purpose of this project is to investigate the effects of different process, material and machine parameters...... on the bond strength of two shot moulded polymers. For the experiments two engineering polymers (PS and ABS) were used. After all the experimental work, several parameters were found which could effectively control the bond strength of two shot moulded polymers. This report also presents different aspects...

  5. Effect of intracanal medicament on bond strength of fibre posts

    Directory of Open Access Journals (Sweden)

    Huda Melike Bayram

    2016-07-01

    Full Text Available The aim of this study was to evaluate the effect of calcium hydroxide (CH, triple antibiotic paste (TAP and double antibiotic paste (DAP on the push-out bond strengths of three different self-adhesive resin cements. Forty-eight single-rooted human maxillary central incisors were selected. The crowns were removed and the root canals were performed. After the irrigation protocols, the post space was prepared. The teeth were then randomly divided into a control group (no intracanal medicament and three medicament groups (n = 12 for each group. After three weeks, the medicaments were removed using 17% ethylenediaminetetraacetic acid, 2.5% sodium hypochlorite and EndoActivator agitation. The teeth were divided into three subgroups according to the fibre-post luting cement: Maxcem Elite, RelyX Unicem and BisCem. The specimens were sectioned and the push-out test was performed. One-way analysis of variance and Tukey's post hoc tests were used for statistical analyses. Regarding the type of cement, BisCem had significantly lower bond strength values than Maxcem and RelyX. There was no significant difference between the bond strength values of Maxcem and RelyX (p > 0.05. The TAP-RelyX group had the highest bond strength value and the DAP-BisCem group had the lowest bond strength value. RelyX and Maxcem had higher bond strength to root canal dentin than BisCem. The bond strength of BisCem, RelyX and Maxcem was not negatively affected by the use of DAP, CH and TAP as intracanal medicaments.

  6. CHARACTERIZATION OF MONOLITHIC FUEL FOIL PROPERTIES AND BOND STRENGTH

    International Nuclear Information System (INIS)

    D E Burkes; D D Keiser; D M Wachs; J S Larson; M D Chapple

    2007-01-01

    Understanding fuel foil mechanical properties, and fuel/cladding bond quality and strength in monolithic plates is an important area of investigation and quantification. Specifically, what constitutes an acceptable monolithic fuel--cladding bond, how are the properties of the bond measured and determined, and what is the impact of fabrication process or change in parameters on the level of bonding? Currently, non-bond areas are quantified employing ultrasonic determinations that are challenging to interpret and understand in terms of irradiation impact. Thus, determining mechanical properties of the fuel foil and what constitutes fuel/cladding non-bonds is essential to successful qualification of monolithic fuel plates. Capabilities and tests related to determination of these properties have been implemented at the INL and are discussed, along with preliminary results

  7. Potential assisted fabrication of metal-ceramic composite coatings

    International Nuclear Information System (INIS)

    Knote, A.; Schindler, U.; Krueger, H.G.; Kern, H.

    2003-01-01

    A possibility to produce uniform metal-ceramic composite coatings with a high content of ceramic particles up to 60 vol.% will be presented in this study. This method includes a combination of electrophoretic deposition and electrolytic deposition by several steps. A yttria-stabilized zirconia coating (Tosoh TZ-8Y) was first electrophoretically deposited on a ferritic steel plate and then sintered by 1100 C to an open porous layer. In the next step nickel was electrodeposited into the pores of the layer. By a final annealing step it was possible to improve the bonding of the composit coating on the substrate by diffusion of the metal components. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [de

  8. Bond strength of dental adhesive systems irradiated with ionizing radiation.

    Science.gov (United States)

    Dibo da Cruz, Adriana; Goncalves, Luciano de Souza; Rastelli, Alessandra Nara de Souza; Correr-Sobrinho, Lorenco; Bagnato, Vanderlei Salvador; Boscolo, Frab Norberto

    2010-04-01

    The aim of the present paper was to determine the effect of different types of ionizing radiation on the bond strength of three different dentin adhesive systems. One hundred twenty specimens of 60 human teeth (protocol number: 032/2007) sectioned mesiodistally were divided into 3 groups according to the adhesives systems used: SB (Adper Single Bond Plus), CB (Clearfil SE Bond) and AP (Adper Prompt Self-Etch). The adhesives were applied on dentin and photo-activated using LED (Lec 1000, MMoptics, 1000 mW/cm2). Customized elastomer molds (0.5 mm thickness) with three orifices of 1.2 mm diameter were placed onto the bonding areas and filled with composite resin (Filtek Z-250), which was photo-activated for 20 s. Each group was subdivided into 4 subgroups for application of the different types of ionizing radiation: ultraviolet radiation (UV), diagnostic x-ray radiation (DX), therapeutic x-ray radiation (TX) and without irradiation (control group, CG). Microshear tests were carried out (Instron, model 4411), and afterwards the modes of failure were evaluated by optical and scanning electron microscope and classified using 5 scores: adhesive failure, mixed failures with 3 significance levels, and cohesive failure. The results of the shear bond strength test were submitted to ANOVA with Tukey's test and Dunnett's test, and the data from the failure pattern evaluation were analyzed with the Mann Whitney test (p = 0.05). No change in bond strength of CB and AP was observed after application of the different radiation types, only SB showed increase in bond strength after UV (p = 0.0267) irradiation. The UV also changed the failure patterns of SB (p = 0.0001). The radio-induced changes did not cause degradation of the restorations, which means that they can be exposed to these types of ionizing radiation without weakening the bond strength.

  9. Shear bond strength of hydrophilic adhesive systems to enamel.

    Science.gov (United States)

    Hara, A T; Amaral, C M; Pimenta, L A; Sinhoreti, M A

    1999-08-01

    To compare the enamel shear bond strength of four hydrophilic adhesive systems: one multiple-bottle (Scotchbond Multi-Purpose Plus), two one-bottle (Stae, Single Bond) and one self-etching (Etch & Prime). 120 bovine incisor teeth were obtained, embedded in polyester resin, polished to 600 grit to form standardized enamel surfaces, and randomly assigned to four groups (n = 30). Each adhesive system was used on enamel according to the manufacturer's instructions, and resin-based composite (Z100) cylinders with 3 mm diameter and 5 mm height were bonded. Specimens were stored in humid environment for 1 week, and bond strength was determined using a universal testing machine, at a crosshead speed of 0.5 mm/minute. The mean shear bond strength values (MPa +/- SD) were: Single Bond: 24.28 +/- 5.27 (a); Scotchbond Multi-Purpose Plus: 21.18 +/- 4.35 (ab); Stae: 19.56 +/- 4.71 (b); Etch & Prime 3.0: 15.13 +/- 4.92 (c). ANOVA revealed significant difference in means (P < 0.01) and Tukey's test showed the statistical differences that are expressed by different letters for each group. It could be concluded that the self-etching adhesive system did not provide as good a bond to enamel surface, as did the one- and multiple-bottle systems.

  10. Bond strength with various etching times on young permanent teeth

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W.N.; Lu, T.C. (School of Dentistry, National Defense Medical Center, Taipei, Taiwan (China))

    1991-07-01

    Tensile bond strengths of an orthodontic resin cement were compared for 15-, 30-, 60-, 90-, or 120-second etching times, with a 37% phosphoric acid solution on the enamel surfaces of young permanent teeth. Fifty extracted premolars from 9- to 16-year-old children were used for testing. An orthodontic composite resin was used to bond the bracket directly onto the buccal surface of the enamel. The tensile bond strengths were tested with an Instron machine. Bond failure interfaces between bracket bases and teeth surfaces were examined with a scanning electron microscope and calculated with mapping of energy-dispersive x-ray spectrometry. The results of tensile bond strength for 15-, 30-, 60-, or 90-second etching times were not statistically different. For the 120-second etching time, the decrease was significant. Of the bond failures, 43%-49% occurred between bracket and resin interface, 12% to 24% within the resin itself, 32%-40% between resin and tooth interface, and 0% to 4% contained enamel fragments. There was no statistical difference in percentage of bond failure interface distribution between bracket base and resin, resin and enamel, or the enamel detachment. Cohesive failure within the resin itself at the 120-second etching time was less than at other etching times, with a statistical significance. To achieve good retention, to decrease enamel loss, and to reduce moisture contamination in the clinic, as well as to save chairside time, a 15-second etching time is suggested for teenage orthodontic patients.

  11. Microtensile bond strength to enamel affected by hypoplastic amelogenesis imperfecta.

    Science.gov (United States)

    Yaman, Batu Can; Ozer, Fusun; Cabukusta, Cigdem Sozen; Eren, Meltem M; Koray, Fatma; Blatz, Markus B

    2014-02-01

    This study compared the microtensile bond strengths (μTBS) of two different self-etching (SE) and etchand- rinse (ER) adhesive systems to enamel affected by hypoplastic amelogenesis imperfecta (HPAI) and analyzed the enamel etching patterns created by the two adhesive systems using scanning electron microscopy (SEM). Sixteen extracted HPAI-affected molars were used for the bond strength tests and 2 molars were examined under SEM for etching patterns. The control groups consisted of 12 healthy third molars for μTBS tests and two molars for SEM. Mesial and distal surfaces of the teeth were slightly ground flat. The adhesive systems and composite resin were applied to the flat enamel surfaces according to the manufacturers' instructions. The tooth slabs containing composite resin material on their mesial and distal surfaces were cut in the mesio-distal direction with a slow-speed diamond saw. The slabs were cut again to obtain square, 1-mm-thick sticks. Finally, each stick was divided into halves and placed in the μTBS tester. Bond strength tests were performed at a speed of 0.5 mm/min. Data were analyzed with two-way ANOVA and Tukey's tests. There was no significant difference between the bond strength values of ER and SE adhesives (p > 0.05). However, significant differences were found between HPAI and control groups (p systems provide similar bond strengths to HPAI-affected enamel surfaces.

  12. Comparative Evaluation of Effects of Laser Modalities on Shear Bond Strengths of Veneering Porcelains to Laser Sintered Substructures: An In Vitro Study.

    Science.gov (United States)

    Gorler, Oguzhan; Saygin, Aysegul Goze

    2017-06-01

    Laser modalities and direct metal laser sintering (DMLS) have a potential to enhance micromechanical bonding between dental super- and infrastructures. However, the effect of different manufacturing methods on the metal-ceramic bond strength needs further evaluation. We investigated the effect of surface treatment with Er:YAG, Nd:YAG, and Ho:YAG lasers on the shear bond strength (SBS) of high-fusion dental porcelains (Vita and G-Ceram) to infrastructures prepared with DMLS in vitro settings. Study specimens (n = 128) were randomly divided into study subsets (n = 8), considering treatment types applied on the surface of infrastructures, including sandblasting and selected laser modalities; infrastructure types as direct laser sintered (DLS) and Ni-Cr based; and superstructure porcelains as Vita and G-Ceram. The SBS test was performed to assess the effectiveness of surface modifications that were also examined with a stereo microscope. Considering laser procedure types, the highest SBS values were obtained by Er:YAG laser, followed by, with a decreasing efficiency, Ho:YAG laser and sandblasting procedures, and Nd:YAG laser procedure (p laser decreases the bonding of Vita and G-Ceram in all the infrastructures compared with sandblasting. Considering porcelains, the highest SBS values were obtained by Vita (p laser procedures caused surface irregularities as revealed by the stereo microscopic examination. In current experimental settings, Er:YAG laser applied to DLS infrastructure veneered with Vita porcelain increases bonding strength more distinctly, and Nd:YAG laser applied to Ni-Cr-based infrastructure veneered with G-Ceram porcelain alters bonding strength unfavorably.

  13. Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-Filled Composites

    OpenAIRE

    Chalipa, Javad; Akhondi, Mohammad Sadegh Ahmad; Arab, Sepideh; Kharrazifard, Mohammad Javad; Ahmadyar, Maryam

    2013-01-01

    Objectives: The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel...

  14. Tensile bond strength of metal bracket bonding to glazed ceramic surfaces with different surface conditionings.

    Science.gov (United States)

    Akhoundi, Ms Ahmad; Kamel, M Rahmati; Hashemi, Sh Mahmood; Imani, M

    2011-01-01

    The objective of this study was to compare the tensile bond strength of metal brackets bonding to glazed ceramic surfaces using three various surface treatments. Forty two glazed ceramic disks were assigned to three groups. In the first and second groups the specimens were etched with 9.5% hydrofluoric acid (HFA). Subsequently in first group, ceramic primer and adhesive were applied, but in second group a bonding agent alone was used. In third group, specimens were treated with 35% phosphoric acid followed by ceramic primer and adhesive application. Brackets were bonded with light cure composites. The specimens were stored in distilled water in the room temperature for 24 hours and thermocycled 500 times between 5°C and 55°C. The universal testing machine was used to test the tensile bond strength and the adhesive remenant index scores between three groups was evaluated. The data were subjected to one-way ANOVA, Tukey and Kruskal-Wallis tests respectively. The tensile bond strength was 3.69±0.52 MPa forfirst group, 2.69±0.91 MPa for second group and 3.60±0.41 MPa for third group. Group II specimens showed tensile strength values significantly different from other groups (Ptensile bond strength.

  15. Bonding polycarbonate brackets to ceramic: : Effects of substrate treatment on bond strength

    NARCIS (Netherlands)

    Özcan, Mutlu; Vallittu, Pekka K.; Peltomäki, Timo; Huysmans, Marie-Charlotte; Kalk, Warner

    2004-01-01

    This study evaluated the effects of 5 different surface conditioning methods on the bond strength of polycarbonate brackets bonded to ceramic surfaces with resin based cement. Six disc-shaped ceramic specimens (feldspathic porcelain) with glazed surfaces were used for each group. The specimens were

  16. Shear bond strength of indirect composite material to monolithic zirconia.

    Science.gov (United States)

    Sari, Fatih; Secilmis, Asli; Simsek, Irfan; Ozsevik, Semih

    2016-08-01

    This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (α=.05). Bond strength was significantly lower in untreated specimens than in sandblasted specimens (Pcomposite material and monolithic zirconia.

  17. Microstructure and bonding strength of Ni-based alloy coating

    Directory of Open Access Journals (Sweden)

    LIU Qing

    2006-05-01

    Full Text Available A Ni-Cr-B-Si coating technique was developed and successfully applied on austenite grey iron substrate in a conventional resistance furnace under graphite powder protection. The microstructure, phase distribution, chemical composition profile and microhardness along the coating layer depth were investigated. Shear strength of the coating was also tested. Microanalysis shows that the coating is consist of γ-Ni solution and γ-Ni+Ni3B lamellar eutectic, as well as small amount of Cr5B3 particles. Diffusion induced metallurgical bonding occurs at the coating/substrate interfaces, and the higher the temperature, the more sufficient elements diffused, the broader interfusion region and the larger bonding strength, but it has an optimum value. And the bonding strength at the interface can be enable to reach 250-270 MPa, which is nearly the same as that of processed by flame spray. The microhardness along the coating layer depth shows a gradient distribution manner.

  18. Dentine bond strength and antimicrobial activity evaluation of adhesive systems.

    Science.gov (United States)

    André, Carolina Bosso; Gomes, Brenda Paula Figueiredo Almeida; Duque, Thais Mageste; Stipp, Rafael Nobrega; Chan, Daniel Chi Ngai; Ambrosano, Glaucia Maria Bovi; Giannini, Marcelo

    2015-04-01

    This study evaluated the dentine bond strength (BS) and the antibacterial activity (AA) of six adhesives against strict anaerobic and facultative bacteria. Three adhesives containing antibacterial components (Gluma 2Bond (glutaraldehyde)/G2B, Clearfil SE Protect (MDPB)/CSP and Peak Universal Bond (PUB)/chlorhexidine) and the same adhesive versions without antibacterial agents (Gluma Comfort Bond/GCB, Clearfil SE Bond/CSB and Peak LC Bond/PLB) were tested. The AA of adhesives and control groups was evaluated by direct contact method against four strict anaerobic and four facultative bacteria. After incubation, according to the appropriate periods of time for each microorganism, the time to kill microorganisms was measured. For BS, the adhesives were applied according to manufacturers' recommendations and teeth restored with composite. Teeth (n=10) were sectioned to obtain bonded beams specimens, which were tested after artificial saliva storage for one week and one year. BS data were analyzed using two-way ANOVA and Tukey test. Saliva storage for one year reduces the BS only for GCB. In general G2B and GCB required at least 24h for killing microorganisms. PUB and PLB killed only strict anaerobic microorganisms after 24h. For CSP the average time to eliminate the Streptococcus mutans and strict anaerobic oral pathogens was 30 min. CSB showed no AA against facultative bacteria, but had AA against some strict anaerobic microorganisms. Storage time had no effect on the BS for most of the adhesives. The time required to kill bacteria depended on the type of adhesive and never was less than 10 min. Most of the adhesives showed stable bond strength after one year and the Clearfil SE Protect may be a good alternative in restorative procedures performed on dentine, considering its adequate bond strength and better antibacterial activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Experimental investigation of bond strength under high loading rates

    Directory of Open Access Journals (Sweden)

    Michal Mathias

    2015-01-01

    Full Text Available The structural behaviour of reinforced concrete is governed significantly by the transmission of forces between steel and concrete. The bond is of special importance for the overlapping joint and anchoring of the reinforcement, where rigid bond is required. It also plays an important role in the rotational capacity of plastic hinges, where a ductile bond behaviour is preferable. Similar to the mechanical properties of concrete and steel also the characteristics of their interaction changes with the velocity of the applied loading. For smooth steel bars with its main bond mechanisms of adhesion and friction, nearly no influence of loading rate is reported in literature. In contrast, a high rate dependence can be found for the nowadays mainly used deformed bars. For mechanical interlock, where ribs of the reinforcing steel are bracing concrete material surrounding the bar, one reason can be assumed to be in direct connection with the increase of concrete compressive strength. For splitting failure of bond, characterized by the concrete tensile strength, an even higher dynamic increase is observed. For the design of Structures exposed to blast or impact loading the knowledge of a rate dependent bond stress-slip relationship is required to consider safety and economical aspects at the same time. The bond behaviour of reinforced concrete has been investigated with different experimental methods at the University of the Bundeswehr Munich (UniBw and the Joint Research Centre (JRC in Ispra. Both static and dynamic tests have been carried out, where innovative experimental apparatuses have been used. The bond stress-slip relationship and maximum pull-out-forces for varying diameter of the bar, concrete compressive strength and loading rates have been obtained. It is expected that these experimental results will contribute to a better understanding of the rate dependent bond behaviour and will serve for calibration of numerical models.

  20. Shear Bond Strengths of Different Adhesive Systems to Biodentine

    Science.gov (United States)

    Odabaş, Mesut Enes; Bani, Mehmet; Tirali, Resmiye Ebru

    2013-01-01

    The aim of this study was to measure the shear bond strength of different adhesive systems to Biodentine with different time intervals. Eighty specimens of Biodentine were prepared and divided into 8 groups. After 12 minutes, 40 samples were randomly selected and divided into 4 groups of 10 each: group 1: (etch-and-rinse adhesive system) Prime & Bond NT; group 2: (2-step self-etch adhesive system) Clearfil SE Bond; group 3: (1-step self-etch adhesive systems) Clearfil S3 Bond; group 4: control (no adhesive). After the application of adhesive systems, composite resin was applied over Biodentine. This procedure was repeated 24 hours after mixing additional 40 samples, respectively. Shear bond strengths were measured using a universal testing machine, and the data were subjected to 1-way analysis of variance and Scheffé post hoc test. No significant differences were found between all of the adhesive groups at the same time intervals (12 minutes and 24 hours) (P > .05). Among the two time intervals, the lowest value was obtained for group 1 (etch-and-rinse adhesive) at a 12-minute period, and the highest was obtained for group 2 (two-step self-etch adhesive) at a 24-hour period. The placement of composite resin used with self-etch adhesive systems over Biodentine showed better shear bond strength. PMID:24222742

  1. Characterization of Dentine to Assess Bond Strength of Dental Composites

    Directory of Open Access Journals (Sweden)

    Saad Liaqat

    2015-04-01

    Full Text Available This study was performed to develop alternating dentine adhesion models that could help in the evaluation of a self-bonding dental composite. For this purpose dentine from human and ivory was characterized chemically and microscopically before and after acid etching using Raman and SEM. Mechanical properties of dentine were determined using 3 point bend test. Composite bonding to dentine, with and without use of acid pre-treatment and/or the adhesive, were assessed using a shear bond test. Furthermore, micro gap formation after restoration of 3 mm diameter cavities in dentine was assessed by SEM. Initial hydroxyapatite level in ivory was half that in human dentine. Surface hydroxyapatites decreased by approximately half with every 23 s of acid etch. The human dentine strength (56 MPa was approximately double that of ivory, while the modulus was almost comparable to that of ivory. With adhesive use, average shear bond strengths were 30 and 26 MPa with and without acid etching. With no adhesive, average bond strength was 6 MPa for conventional composites. This, however, increased to 14 MPa with a commercial flowable “self–bonding” composite or upon addition of low levels of an acidic monomer to the experimental composite. The acidic monomer additionally reduced micro-gap formation with the experimental composite. Improved bonding and mechanical properties should reduce composite failures due to recurrent caries or fracture respectively.

  2. Estimation and comparison of tensile bond strengths at resin-dentin ...

    African Journals Online (AJOL)

    Nigerian Dental Journal ... Result: Etch-and-rinse adhesive Adper Single Bond 2 Total Etch® yielded high bond strength ... The self etch systems though convenient to use, do not match the bond strengths of conventional total etch systems.

  3. Comparison of shear bond strength of stainless steel brackets bonded with three light- cured adhesives

    Directory of Open Access Journals (Sweden)

    Zahra Minaei Basharik

    2015-09-01

    Full Text Available Introduction: The bonding process of the brackets to enamel has been a critical issue in orthodontic research. The purpose of this study was to evaluate the shear bond strength of 3 light-cured adhesives (transbond XT, Z250, light bond. Materials &Methods: In this study sixty extracted human premolars were collected and randomly divided into 3 test groups. All teeth were etched by 37% phosphoric acid. In first group brackets were bonded by Transbond XT adhesive, in group two brackets were bonded by Light bond adhesive and in third group were bonded by filtek Z250 composite. All of them were cured with Ortholux xt for 40 seconds.24 hours after thermocycling, Shear Bond Strength (SBS values of these brackets were recorded using a Universal Testing Machine. Adhesive Remnant Index (ARI scores were determined after the failure of the brackets, using Stereo Microscope the data were analyzed using ANOVA and Chi-square tests. Results: Mean shear bond strength of Transbond XT, light bond and Z250 were 28.9±2.25 MPa, 25.06±1.98 MPa and 26.8±2.57 MPa, respectively. No significant difference was observed in the SBS among the groups and a clinically acceptable SBS was found for the three adhesives. ARI scores were not significantly different between the various groups (P>0.05. Conclusion: This study showed that the Z250 can be used as light bond and transbond xt to bond orthodontic brackets and ARI and SBS scores were not significantly different.

  4. The assessment of bond strength between heat damaged concrete and high strength fibre reinforced concrete

    Science.gov (United States)

    Zahid, M. Z. A. Mohd; Muhamad, K.

    2017-09-01

    The aim of this study is to assess the bond strength between heat damaged concrete and high strength fibre reinforced concrete (HPFRC). Firstly, this paper presents the various steps taken to prepare the HPFRC with self-compacting property. The minimum targeted slump flow is 600 mm and minimum targeted compressive strength is 80 MPa. The key mix variables considered are such as type of superplasticizer, water cement ratio and silica fume content. Then, the bond strength between the heat damaged concrete with HPFRC was examined. The experimental parameters are heating temperature, surface treatment technique and curing method and the results show that, all experimental parameters are significantly affected the bond strength between heat damaged concrete and HPFRC.

  5. Tensile Bond Strength of Metal Bracket Bonding to Glazed Ceramic Surfaces With Different Surface Conditionings

    Directory of Open Access Journals (Sweden)

    M. Imani

    2011-12-01

    Full Text Available Objective: The objective of this study was to compare the tensile bond strength of metal brackets bonding to glazed ceramic surfaces using three various surface treatments.Materials and Methods: Forty two glazed ceramic disks were assigned to three groups. In the first and second groups the specimens were etched with 9.5% hydrofluoric acid (HFA. Subsequently in first group, ceramic primer and adhesive were applied, but in second group a bonding agent alone was used. In third group, specimens were treated with 35% phosphoric acid followed by ceramic primerand adhesive application. Brackets were bonded with light cure composites. The specimens were stored in distilled water in the room temperature for 24 hours and thermocycled 500 times between 5°C and 55°C. The universal testing machine was used to test the tensile bond strength and the adhesive remenant index scores between three groups was evaluated. The data were subjected to one-way ANOVA, Tukey and Kruskal-Wallis tests respectively.Results: The tensile bond strength was 3.69±0.52 MPa forfirst group, 2.69±0.91 MPa for second group and 3.60±0.41 MPa for third group. Group II specimens showed tensile strength values significantly different from other groups (P<0.01.Conclusion: In spite of limitations in laboratory studies it may be concluded that in application of Scotch bond multipurpose plus adhesive, phosphoric acid can be used instead of HFA for bonding brackets to the glazed ceramic restorations with enough tensile bond strength.

  6. Bond strength of resin composite to differently conditioned amalgam

    NARCIS (Netherlands)

    Ozcan, M; Vallittu, PK; Huysmans, MC; Kalk, W; Vahlberg, T

    Bulk fracture of teeth, where a part of the amalgam restoration and/or the cusp is fractured, is a common clinical problem. The aim of this study was to evaluate the effect of different surface conditioning methods on the shear bond strength of a hybrid resin composite to fresh amalgam. Amalgams (N

  7. ADHESIVE SYSTEM AFFECTS REPAIR BOND STRENGTH OF RESIN COMPOSITE

    Directory of Open Access Journals (Sweden)

    Özgür IRMAK

    2017-10-01

    Full Text Available Purpose: This study evaluated the effects of different adhesive systems on repair bond strength of aged resin composites. Materials and Methods: Ninety composite discs were built and half of them were subjected to thermal aging. Aged and non-aged specimens were repaired with resin composite using three different adhesive systems; a two-step self-etch adhesive, a two-step total-etch adhesive and a one-step self-etch adhesive; then they were subjected to shear forces. Data were analyzed statistically. Results: Adhesive type and aging significantly affected the repair bond strengths (p<0.0001. No statistical difference was found in aged composite groups repaired with two-step self- etch or two-step total-etch adhesive. One-step self-etch adhesive showed lower bond strength values in aged composite repair (p<0.0001. Conclusion: In the repair of aged resin composite, two-step self-etch and two-step total-etch adhesives exhibited higher shear bond strength values than that of one-step self-etch adhesive.

  8. Shear Bond Strength of a Novel Porcelain Repair System for ...

    African Journals Online (AJOL)

    2018-04-04

    Apr 4, 2018 ... Each fracture type was examined under a stereomicroscope .... fracture types. Statistical analysis. The normal distribution of data was examined using the Kolmogorov–Smirnov test. Shear bond strength data of repaired CAD/CAM .... adhesives to enamel, dentine, and porcelain surfaces can be compared.

  9. Effect of simulated pulpal pressure on composite bond strength to ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Key words: Bond strength, laser treatment, pulpal pressure, resin composite. INTRODUCTION ... bilities for operative and esthetic dentistry (Kato and. Nakabayashi ... E-mail: kimyais@tbzmed.ac.ir. Tel: 0098411- ... pulse repetition rate of 20 pulses per second (20 Hz). ..... Stern RH, Sognnaes RF (1965).

  10. Bond strength of plasma sprayed ceramic coatings on phosphate steels

    Czech Academy of Sciences Publication Activity Database

    Pokorný, P.; Mastný, L.; Sýkora, V.; Pala, Zdeněk; Brožek, Vlastimil

    2015-01-01

    Roč. 54, č. 2 (2015), s. 411-414 ISSN 0543-5846 R&D Projects: GA ČR(CZ) GAP108/12/1872 Institutional support: RVO:61389021 Keywords : phosphating * plasma spraying * ceramic coatings * corrosion * bond strength Subject RIV: CA - Inorganic Chemistry Impact factor: 0.959, year: 2014

  11. Fluoride release/recharging ability and bond strength of glass ...

    African Journals Online (AJOL)

    2015-08-17

    Aug 17, 2015 ... 2017 Nigerian Journal of Clinical Practice | Published by Wolters Kluwer - ... Objectives: The aim of this in vitro study was to evaluate the microtensile bond strength (μTBS) of different glass ... Glass ionomer cements (GICs) have often been used as the ... with nano‑fluoride‑/hydroxyapatite or resin‑modified.

  12. Relationship between thin-film bond strength as measured by a scratch test, and indentation hardness for bonding agents.

    Science.gov (United States)

    Kusakabe, Shusuke; Rawls, H Ralph; Hotta, Masato

    2016-03-01

    To evaluate thin-film bond strength between a bonding agent and human dentin, using a scratch test, and the characteristics and accuracy of measurement. One-step bonding agents (BeautiBond; Bond Force; Adper Easy Bond; Clearfil tri-S Bond) and two-step bonding agents (Cleafil SE Bond; FL-Bond II) were investigated in this study. Flat dentin surfaces were prepared for extracted human molars. The dentin surfaces were ground and bonding agents were applied and light cured. The thin-film bond strength test of the specimens was evaluated by the critical load at which the coated bonding agent failed and dentin appeared. The scratch mark sections were then observed under a scanning electron microscope. Indentation hardness was evaluated by the variation in depth under an applied load of 10gf. Data were compared by one-way ANOVA with the Scheffé's post hoc multiple comparison test (pstrength and indentation hardness were analyzed using analysis of correlation and covariance. The thin-film bond strength of two-step bonding agents were found to be significantly higher than that of one-step bonding agents with small standard deviations. Scratch marks consistently showed adhesive failure in the vicinity of the bonding agent/dentin interface. The indentation hardness showed a trend that two-step bonding agents have greater hardness than one-step bonding agents. A moderately significant correlation (r(2)=0.31) was found between thin-film bond strength and indentation hardness. Thin-film bond strength test is a valid and reliable means of evaluating bond strength in the vicinity of the adhesive interface and is more accurate than other methods currently in use. Further, the thin-film bond strength is influenced by the hardness of the cued bonding agent. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  13. Repair Bond Strength of Aged Resin Composite after Different Surface and Bonding Treatments

    Directory of Open Access Journals (Sweden)

    Michael Wendler

    2016-07-01

    Full Text Available The aim of this study was to compare the effect of different mechanical surface treatments and chemical bonding protocols on the tensile bond strength (TBS of aged composite. Bar specimens were produced using a nanohybrid resin composite and aged in distilled water for 30 days. Different surface treatments (diamond bur, phosphoric acid, silane, and sandblasting with Al2O3 or CoJet Sand, as well as bonding protocols (Primer/Adhesive were used prior to application of the repair composite. TBS of the specimens was measured and the results were analyzed using analysis of variance (ANOVA and the Student–Newman–Keuls test (α = 0.05. Mechanically treated surfaces were characterized under SEM and by profilometry. The effect of water aging on the degree of conversion was measured by means of FTIR-ATR spectroscopy. An important increase in the degree of conversion was observed after aging. No significant differences in TBS were observed among the mechanical surface treatments, despite variations in surface roughness profiles. Phosphoric acid etching significantly improved repair bond strength values. The cohesive TBS of the material was only reached using resin bonding agents. Application of an intermediate bonding system plays a key role in achieving reliable repair bond strengths, whereas the kind of mechanical surface treatment appears to play a secondary role.

  14. Effect of Delayed Bonding and Antioxidant Application on the Bond Strength to Enamel after Internal Bleaching.

    Science.gov (United States)

    Kılınç, Halil İbrahim; Aslan, Tuğrul; Kılıç, Kerem; Er, Özgür; Kurt, Gökmen

    2016-07-01

    This study evaluated the effect of delayed bonding and antioxidant application (AA, 10% sodium ascorbate) after internal bleaching (35% carbamide peroxide) on the shear bond strength of an adhesive cement to enamel. Eighty-four human maxillary central incisors were endodontically treated. The control group remained unbleached with no AA. Experimental groups were all internally bleached. The buccal enamel was finished and polished with metallographic paper to a refinement of #600, in order to obtain a 5-mm(2) flat bonding area. An adhesive cement (Clearfil Esthetic) was placed into a plastic tube with internal diameter of 3 mm and a 3-mm height and cured on the enamel. Bonding occurred either immediately after bleaching (group Im), a 7-day delay (group 7), or a 14-day delay (group 14), and half the specimens were treated with antioxidant application (groups Im-AA, 7-AA, and 14-AA). Shear bond strength testing was performed on a universal testing machine, and data were analyzed with ANOVA and Fisher test (5%). Delaying of bonding is a useful factor for enhancing shear bond strength (p adhesive cementation to enamel is recommended only when delayed 14 days, or delayed 7 days with sodium ascorbate application. © 2015 by the American College of Prosthodontists.

  15. Microtensile bond strength of eleven contemporary adhesives to enamel.

    Science.gov (United States)

    Inoue, Satoshi; Vargas, Marcos A; Abe, Yasuhiko; Yoshida, Yasuhiro; Lambrechts, Paul; Vanherle, Guido; Sano, Hidehiko; Van Meerbeek, Bart

    2003-10-01

    To compare the microtensile bond strength (microTBS) to enamel of 10 contemporary adhesives, including three one-step self-etch systems, four two-step self-etch systems and three two-step total-etch systems, with that of a conventional three-step total-etch adhesive. Resin composite (Z100, 3M) was bonded to flat, #600-grit wet-sanded enamel surfaces of 18 extracted human third molars using the adhesives strictly according to the respective manufacturer's instructions. After storage overnight in 37 degrees C water, the bonded specimens were sectioned into 2-4 thin slabs of approximately 1 mm thickness and 2.5 mm width. They were then trimmed into an hourglass shape with an interface area of approximately 1 mm2, and subsequently subjected to microTBS-testing with a cross-head speed of 1 mm/minute. The microTBS to enamel varied from 3.2 MPa for the experimental one-step self-etch adhesive PQ/Universal (self-etch) to 43.9 MPa for the two-step total-etch adhesive Scotchbond 1. When compared with the conventional three-step total-etch adhesive OptiBond FL, the bond strengths of most adhesives with simplified application procedures were not significantly different, except for two one-step self-etch adhesives, experimental PQ/Universal (self-etch) and One-up Bond F, that showed lower bond strengths. Specimen failures during sample preparation were recorded for the latter adhesives as well.

  16. Clinical study on the reasons for and location of failures of metal-ceramic restorations and survival of repairs

    NARCIS (Netherlands)

    Ozcan, M; Niedermeier, W

    2002-01-01

    Purpose: A recently introduced technique, the Cojet system, using SiOx (Al2O3 coated with silisic acid), provides ultrafine mechanical retention by sandblasting, as well as a chemicophysical bond between the metal/ceramic and the composite resin. This study determined the reasons for and locations

  17. In vitro Comparative Evaluation of Tensile Bond Strength of 6(th), 7(th) and 8(th) Generation Dentin Bonding Agents.

    Science.gov (United States)

    Kamble, Suresh S; Kandasamy, Baburajan; Thillaigovindan, Ranjani; Goyal, Nitin Kumar; Talukdar, Pratim; Seal, Mukut

    2015-05-01

    Newer dentin bonding agents were developed to improve the quality of composite restoration and to reduce time consumption in its application. The aim of the present study was to evaluate tensile bond strength of 6(th), 7(th) and 8(th) generation bonding agents by in vitro method. Selected 60 permanent teeth were assigned into 20 in each group (Group I: 6(th) generation bonding agent-Adper SE plus 3M ESPE, Group II: 7(th) generation bonding agent-G-Bond GC Corp Japan and Group III: 8(th) generation dentin adhesives-FuturaBond, DC, Voco, Germany). With high-speed diamond disc, coronal dentin was exposed, and selected dentin bonding agents were applied, followed by composite restoration. All samples were saved in saline for 24 h and tensile bond strength testing was done using a universal testing machine. The obtained data were tabulated and statistically analyzed using ANOVA test. The tensile bond strength readings for 6(th) generation bonding agent was 32.2465, for 7(th) generation was 31.6734, and for 8(th)-generation dentine bonding agent was 34.74431. The highest tensile bond strength was seen in 8(th) generation bonding agent compared to 6(th) and 7(th) generation bonding agents. From the present study it can be conclude that 8(th) generation dentine adhesive (Futura DC, Voco, Germany) resulted in highest tensile bond strength compared to 6(th) (Adper SE plus, 3M ESPE) and 7(th) generation (G-Bond) dentin bonding agents.

  18. Bond lengths and bond strengths in compounds of the 5f elements

    International Nuclear Information System (INIS)

    Zachariasen, W.H.

    1975-01-01

    The variation of bond length (D) with bond strength (S) in normal valence compounds of 3d, 4d, 5d-4f, and 6d-5f elements can be represented approximately as D(S)=D(0.5) F(S), where D(0.5) is a characteristic constant for a given bond and F(S) an empirical function which is the same for all bonds. A bond strength Ssub(ij)=ssub(ji) is assigned to the bond between atoms i and j such that Σsub(j) Ssub(ij)=vsub(i) and Σsub(i) Ssub(ij)=vsub(j), where vsub(i) and vsub(j) are the normal valences of the two atoms. The function F(S) decreases monotonically with increasing S, and is normalized to unity at S=0.5, so that the constant D(0.5) has the physical meaning of being the bond length adjusted to S=0.5. The method described above was used to interpret and systematize the experimental results on bond lengths in oxides, halides, and oxyhalides of the 5f elements. (U.S.)

  19. Effect of composite warming on shear bond strength.

    Science.gov (United States)

    McDaniel, Thomas F; Sigrist, Thomas W; Johnson, Gary M

    2018-01-01

    Several manufacturers produce devices designed to warm composite resins used in restorative dentistry. Previous investigators have examined the effects of heating composite restorative resins prior to placement and polymerization. Heating has been reported to reduce viscosity, improve ease of placement, enhance monomer conversion, and reduce microleakage. The aim of the present study was to compare shear bond strengths of room temperature (22°C) and prewarmed (54°C) restorative composite resin. Extracted bovine mandibular incisors were sectioned sagittally and embedded in acrylic cylinders. Enamel was selectively etched with 37% phosphoric acid, rinsed, and dried. Self-etching primer was applied to both enamel and dentin. Self-etching adhesive was then applied and photopolymerized. Composite resin capsules were then divided into prewarmed and room temperature groups. Fourteen composite specimens prewarmed in an incubator were applied to the prepared enamel and dentin and photopolymerized. Fourteen room temperature composite specimens were likewise placed. After storage in water for 24 hours, all composite specimens were subjected to shear stress testing. The resulting data were analyzed with a t test (P = 0.05). There was no statistically significant difference between the shear bond strengths of the prewarmed and room temperature composite resin specimens. Warming does not appear to affect bond strength of composite resin bonded to both dentin and enamel.

  20. Bond strength test of acrylic artificial teeth with prosthetic base

    Directory of Open Access Journals (Sweden)

    Erna Kurnikasari

    2008-07-01

    Full Text Available Denture consists of acrylic artificial teeth and acrylic prothesis base bond chemically with a bond strength of 315 kgF/cm2. Most of the commercial acrylic artificial teeth do not specify their specifications and all of those acrylic artificial teeth do not include mechanical data (bond strength. The aim of this study is to discover which acrylic artificial teeth meet ADA specification no. 15. This study is a descriptive analytic study performed to 5 acrylic artificial teeth posterior brands commonly used by dentists and technicians. From each brand, 3 sample teeth were taken. The acrylic artificial teeth were prepared into a rectangular shape and were attached between acrylic prothesis base simulation and jigs. The sample was given tensile load using a Universal Testing Machine. The amount of force that causes the teeth to be fractured was recorded and the bond strength was calculated. The results of the study show that the average value for the five acrylic artificial teeth for the five brands were as followed: Brand A, 125.993 kgF/cm2; B, 188.457 kgF/cm2; C, 175.880 kgF/cm2; D, 153.373 kgF/cm2; E, 82.839 kgF/cm2. The data can be tested statistically by using One Way ANOVA test and Dunnett test (alpha = 0.05. From the study, it is concluded that the five acrylic artificial teeth have a bond strength below the ADA specification no. 15.

  1. Comparison of shear bond strength of amalgam bonded to primary and permanent dentin

    Directory of Open Access Journals (Sweden)

    Mahdi S

    2008-06-01

    Full Text Available Amalgam′s non-adhesive characteristics necessitate cavity preparations incorporating retentive features, which often require the removal of non-carious tooth structure. Use of adhesives beneath amalgam restorations, would be helpful to overcome this disadvantage. This study was undertaken to compare the mean shear bond strength of amalgam bonded to primary and permanent dentin, to evaluate the efficacy of amalgam adhesives in pediatric dentistry.27 primary and 28 permanent posterior teeth with intact buccal or lingual surfaces were grounded to expose dentin and wet-polished with 400-grit silicone carbide paper. Scotchbond Multi Purpose Plus adhesive system was applied to the dentin surfaces and light cured. Amalgam was condensed onto the treated dentin through a plastic mold.shear bond strength testing was done using an Instron Universal testing machine, at a crosshead speed of 0.5 mm/min.The data were analyzed by independent samples t-test The difference among the two groups was not statistically significant (p>0.05 Bonded amalgam showed the same level of bond strength to primary and permanent dentin; so, application of amalgam bonding agents in pediatric dentistry can be recommended.

  2. A novel bonding method for fabrication of PET planar nanofluidic chip with low dimension loss and high bonding strength

    International Nuclear Information System (INIS)

    Yin, Zhifu; Zou, Helin; Sun, Lei; Xu, Shenbo; Qi, Liping

    2015-01-01

    Plastic planar nanofluidic chips are becoming increasingly important for biological and chemical applications. However, the majority of the present bonding methods for planar nanofluidic chips suffer from high dimension loss and low bonding strength. In this work, a novel thermal bonding technique based on O 2 plasma and ethanol treatment was proposed. With the assistance of O 2 plasma and ethanol, the PET (polyethylene terephthalate) planar nanofluidic chip can be bonded at a low bonding temperature of 50 °C. To increase the bonding rate and bonding strength, the O 2 plasma parameters and thermal bonding parameters were optimized during the bonding process. The tensile test indicates that the bonding strength of the PET planar nanofluidic chip can reach 0.954 MPa, while the auto-fluorescence test demonstrates that there is no leakage or blockage in any of the bonded micro- or nanochannels. (paper)

  3. Bond strength of adhesive resin cement with different adhesive systems

    OpenAIRE

    Lorenzoni e Silva, Fabrizio; Pamato, Saulo; Kuga, Milton-Carlos; S?, Marcus-Vinicius-Reis; Pereira, Jefferson-Ricardo

    2017-01-01

    Background To assess the immediate bond strength of a dual-cure adhesive resin cement to the hybridized dentin with different bonding systems. Material and Methods Fifty-six healthy human molars were randomly divided into 7 groups (n=8). After 3 longitudinal sections, the central cuts were included in PVC matrix and were submitted to dentin hybridization according to the groups: G1 - etch & rinse system with 3-step (Apder? Scotchbond? Multi-Purpose, 3M ESPE), G2 - etch & rinse system with 3-s...

  4. Strength and leak testing of plasma activated bonded interfaces

    DEFF Research Database (Denmark)

    Visser, M.M.; Weichel, Steen; Reus, Roger De

    2002-01-01

    on detection of changes in membrane deflections. The detection limit for leak was 8E-13 mbar l/s. For comparison, strength and leak tests were also performed with regular fusion bonded wafers annealed at 1100 degreesC. The PAB was found to withstand post-processing steps such as RCA cleaning, 24 h in de......-ionised water (DIW), 24 h in 2.5% HF, 24 h in acetone and 60 s in a resist developer. By analysing the thin silicon oxide present on the surfaces to be bonded with optical methods, the influence of pre-cleaning and activation process parameters was investigated....

  5. Analysis of factors influencing the bond strength in roll bonding processes

    Science.gov (United States)

    Khaledi, Kavan; Wulfinghoff, Stephan; Reese, Stefanie

    2018-05-01

    Cold Roll Bonding (CRB) is recognized as an industrial technique in which the metal sheets are joined together in order to produce laminate metal composites. In this technique, a metallurgical bond resulting from severe plastic deformation is formed between the rolled metallic layers. The main objective of this paper is to analyse different factors which may affect the bond formation in rolling processes. To achieve this goal, first, an interface model is employed which describes both the bonding and debonding. In this model, the bond strength evolution between the metallic layers is calculated based on the film theory of bonding. On the other hand, the debonding process is modelled by means of a bilinear cohesive zone model. In the numerical section, different scenarios are taken into account to model the roll bonding process of metal sheets. The numerical simulation includes the modelling of joining during the roll bonding process followed by debonding in a Double Cantilever Beam (DCB) peeling test. In all simulations, the metallic layers are regarded as elastoplastic materials subjected to large plastic deformations. Finally, the effects of some important factors on the bond formation are numerically investigated.

  6. Bond strength and stress measurements in thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Gell, M.; Jordan, E. [Univ. of Connecticut, Storrs, CT (United States)

    1995-10-01

    Thermal barrier coatings have been used extensively in aircraft gas turbines for more than 15 years to insulate combustors and turbine vanes from the hot gas stream. Plasma sprayed thermal barrier coatings (TBCs) provide metal temperature reductions as much as 300{degrees}F, with improvements in durability of two times or more being achieved. The introduction of TBCs deposited by electron beam physical vapor deposition (EB-PVD) processes in the last five years has provided a major improvement in durability and also enabled TBCs to be applied to turbine blades for improved engine performance. To meet the aggressive Advanced Turbine Systems goals for efficiency, durability and the environment, it will be necessary to employ thermal barrier coatings on turbine airfoils and other hot section components. For The successful application of TBCs to ATS engines with 2600{degrees}F turbine inlet temperatures and required component lives 10 times greater than those for aircraft gas turbine engines, it is necessary to develop quantitative assessment techniques for TBC coating integrity with time and cycles in ATS engines. Thermal barrier coatings in production today consist of a metallic bond coat, such as an MCrAlY overlay coating or a platinum aluminide (Pt-Al) diffusion coating. During heat treatment, both these coatings form a thin, tightly adherent alumina (Al{sub 2}O{sub 3}) film. Failure of TBC coatings in engine service occurs by spallation of the ceramic coating at or near the bond coat to alumina or the alumina to zirconia bonds. Thus, it is the initial strength of these bonds and the stresses at the bond plane, and their changes with engine exposure, that determines coating durability. The purpose of this program is to provide, for the first time, a quantitative assessment of TBC bond strength and bond plane stresses as a function of engine time and cycles.

  7. Effect of mode of polymerization of bonding agent on shear bond strength of autocured resin composite luting cements.

    Science.gov (United States)

    Dong, Cecilia C S; McComb, Dorothy; Anderson, James D; Tam, Laura E

    2003-04-01

    There have been anecdotal reports of low bond strength with autocured resin composite materials, particularly when light-cured bonding agents that combine primer and adhesive in a 1-bottle preparation are used. The objective of this study was to determine if the mode of polymerization of the bonding agent influences the strength of the attachment of autocured resin composite luting cements to dentin. The shear bond strength of 2 resin luting cements, Calibra and RelyX ARC, polymerized by autocuring, in combination with 4 different bonding agents, Scotchbond Multipurpose Plus, Prime & Bond NT, IntegraBond and Single Bond, polymerized to bovine dentin by light-curing, autocuring or dual-curing, was determined. The pH of each bonding agent and its components was measured. Two-way analysis of variance was used to test the effect of cement and adhesive on shear bond strength. For each bonding agent, the adhesive variable combined the factors product brand and mode of polymerization. With significant interaction among the above variables, the least square means of the 16 combinations of resin cement and adhesive were compared. There was no consistent relationship between shear bond strength and mode of polymerization of the bonding agent. Significant differences in bond strength were specific to the proprietary brand of bonding agent. The pH of the bonding agent depends on the manufacturer's formulation, and low pH may contribute to low bond strength. The low in vitro bond strength occurring with some combinations of bonding agent and resin cement could be clinically significant.

  8. Bond strength of composite resin to enamel: assessment of two ethanol wet-bonding techniques.

    Directory of Open Access Journals (Sweden)

    Maryam Khoroushi

    2014-04-01

    Full Text Available Ethanol wet-bonding (EWB technique has been stated to decrease degradation of resin-dentin bond. This study evaluated the effect of two EWB techniques on composite resin-to-enamel bond strength.Silicon carbide papers were used to produce flat enamel surfaces on the buccal faces of forty-five molars. OptiBond FL (OFL adhesive was applied on enamel surfaces in three groups of 15 namely: Enamel surface and OFL (control;Protocol 1 of the EWB technique: absolute ethanol was applied to water-saturated acid-etched enamel surfaces for 1 minute before the application of ethanol-solvated hydrophobic adhesive resin of OFL 3 times;Protocol 2: progressive ethanol replacement; water was gradually removed from the enamel matrix using ascending ethanol concentrations before OFL application. Composite build-ups were made and the specimens were stored for 24 hours at 37°C and 100% relative humidity. Shear bond strength test was performed using a universal testing machine at 1 mm/min crosshead speed. Fracture patterns were evaluated microscopically. Data were analyzed with one-way ANOVA and Fisher's exact test (α=0.05.There were no significant differences in bond strength between the groups (P=0.73. However, regarding failure patterns, the highest cohesive enamel fractures were recorded in groups 2 and 3.In this study, although both methods of EWB did not influence immediate bond strength of composite resin to enamel, the majority of failure patterns occurred cohesively in enamel.

  9. On the modification of metal/ceramic interfaces by low energy ion/atom bombardment during film growth

    International Nuclear Information System (INIS)

    Rigsbee, J.M.; Scott, P.A.; Knipe, R.K.; Hock, V.F.

    1986-01-01

    Elemental Cu and Ti films have been deposited onto ceramic substrates with a plasma-aided physical vapor deposition (ion-plating) process. This paper discusses how the structure and chemistry of the metallic film and the metal/ceramic interface are modified by low energy ion and neutral atom bombardment. Emphasis is placed on determining how low energy ion/neutral atom bombardment affects the strength of the metal/ceramic interface. Analyses of the film, interface and substrate regions have employed scanning Auger microprobe, secondary ion mass spectroscopy, SEM/STEM-energy dispersive X-ray and TEM/STEM imaging and microdiffraction techniques. (Auth.)

  10. Are Bonding Agents being Effective on the Shear Bond Strength of Orthodontic Brackets Bonded to the Composite?

    Directory of Open Access Journals (Sweden)

    Fahimeh Farzanegan

    2014-06-01

    Full Text Available Introduction: One of the clinical problems in orthodontics is the bonding of brackets tocomposite restorations. The aim of this study was to evaluate the shear bondstrength of brackets bonded to composite restorations using Excite. Methods:Forty brackets were bonded to composite surfaces, which were embedded inacrylic resin. One of the following four protocols was employed for surfacepreparation of the composite: group 1 37% phosphoric acid for 60 seconds, group2 roughening with a diamond bur plus 37% phosphoric acid for 60 seconds, group3 37% phosphoric acid for 60 seconds and the applying Excite®, group4 roughening with diamond bur plus 37% phosphoric acid for 60 seconds andapplying Excite®. Maxillary central brackets were bonded onto thecomposite prepared samples with Transbond XT. Shear Bond Strength (SBS wasmeasured by a universal testing machine. The ANOVA and Tukey test was utilizedfor data analysis. Results: There was a significant difference betweenthe four groups (P

  11. Comparison of Shear Bond Strength of RMGI and Composite Resin for Orthodontic Bracket Bonding

    Science.gov (United States)

    Yassaei, Soghra; Davari, Abdolrahim; Goldani Moghadam, Mahjobeh; Kamaei, Ahmad

    2014-01-01

    Objective: The aim of this study was to compare the shear bond strength (SBS) of resin modified glass ionomer (RMGI) and composite resin for bonding metal and ceramic brackets. Materials and Methods: Eighty-eight human premolars extracted for orthodontic purposes were divided into 4 groups (n=22). In groups 1 and 2, 22 metal and ceramic brackets were bonded using composite resin (Transbond XT), respectively. Twenty-two metal and ceramic brackets in groups 3 and 4, respectively were bonded using RMGI (Fuji Ortho LC, Japan). After photo polymerization, the teeth were stored in water and thermocycled (500 cycles between 5° and 55°). The SBS value of each sample was determined using a Universal Testing Machine. The amount of residual adhesive remaining on each tooth was evaluated under a stereomicroscope. Statistical analyses were done using two-way ANOVA. Results: RMGI bonded brackets had significantly lower SBS value compared to composite resin bonded groups. No statistically significant difference was observed between metal and ceramic brackets bonded with either the RMGI or composite resin. The comparison of the adhesive remnant index (ARI) scores between the groups indicated that the bracket failure mode was significantly different among groups (Porthodontic bonding purposes; however the provided SBS is still within the clinically acceptable range. PMID:25628663

  12. Microtensile bond strength of silorane-based composite specific adhesive system using different bonding strategies

    Directory of Open Access Journals (Sweden)

    Laura AlveBastos

    2015-02-01

    Full Text Available Objectives The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE, the specific self-etching adhesive system (Adhesive System P90, 3M ESPE was used with and without pre-etching (Pre-etching/Silorane and Silorane groups. Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray, with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups, or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE (Three-step/Methacrylate group (n = 6. The restored teeth were sectioned into stick-shaped test specimens (1.0 × 1.0 mm, and coupled to a universal test machine (0.5 mm/min to perform microtensile testing. Results Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p < 0.05. However, it was not significantly different from Preetching/Silorane and Methacrylate groups. Conclusions Pre-etching increased bond strength of silorane-based composite specific adhesive system to dentin.

  13. Factors affecting the shear bond strength of metal and ceramic brackets bonded to different ceramic surfaces.

    Science.gov (United States)

    Abu Alhaija, Elham S J; Abu AlReesh, Issam A; AlWahadni, Ahed M S

    2010-06-01

    The aims of this study were to evaluate the shear bond strength (SBS) of metal and ceramic brackets bonded to two different all-ceramic crowns, IPS Empress 2 and In-Ceram Alumina, to compare the SBS between hydrofluoric acid (HFA), phosphoric acid etched, and sandblasted, non-etched all-ceramic surfaces. Ninety-six all-ceramic crowns were fabricated resembling a maxillary left first premolar. The crowns were divided into eight groups: (1) metal brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (2) metal brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (3) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (4) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (5) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched IPS Empress 2 crowns; (6) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched In-Ceram crowns; (7) metal brackets bonded to sandblasted, non-etched IPS Empress 2 crowns; and (8) metal brackets bonded to sandblasted, non-etched In-Ceram crowns. Metal and ceramic orthodontic brackets were bonded using a conventional light polymerizing adhesive resin. An Instron universal testing machine was used to determine the SBS at a crosshead speed of 0.1 mm/minute. Comparison between groups was performed using a univariate general linear model and chi-squared tests. The highest mean SBS was found in group 3 (120.15 +/- 45.05 N) and the lowest in group 8 (57.86 +/- 26.20 N). Of all the variables studied, surface treatment was the only factor that significantly affected SBS (P Empress 2 and In-Ceram groups.

  14. Repair bond strength of resin composite to bilayer dental ceramics

    Science.gov (United States)

    2018-01-01

    PURPOSE The purpose of this study was to investigate the effect of various surface treatments (ST) on the shear bond strength of resin composite to three bilayer dental ceramics made by CAD/CAM and two veneering ceramics. MATERIALS AND METHODS Three different bilayer dental ceramics and two different veneering ceramics were used (Group A: IPS e.max CAD+IPS e.max Ceram; Group B: IPS e.max ZirCAD+IPS e.max Ceram, Group C: Vita Suprinity+Vita VM11; Group D: IPS e.max Ceram; Group E: Vita VM11). All groups were divided into eight subgroups according to the ST. Then, all test specimens were repaired with a nano hybrid resin composite. Half of the test specimens were subjected to thermocycling procedure and the other half was stored in distilled water at 37℃. Shear bond strength tests for all test specimens were carried out with a universal testing machine. RESULTS There were statistically significant differences among the tested surface treatments within the all tested fracture types (P.00125). CONCLUSION This study revealed that HF etching for glass ceramics and sandblasting for zirconia ceramics were adequate for repair of all ceramic restorations. The effect of ceramic type exposed on the fracture area was not significant on the repair bond strength of resin composites to different ceramic types. PMID:29713430

  15. Bond strength between zirconium ceramic and dual resinous cement

    Directory of Open Access Journals (Sweden)

    João Galan Junior

    2010-04-01

    Full Text Available Objective: To assess the influence of different surface treatments on the bond strength between the resinous cement Panavia F (Kuraray Co. Ltd., Osaka, Japan and the structure of In-Ceram YZ (Vita Zahnfabrik, Bad Säckingen, Germany. Methods: Fifteen ceramic blocks were assessed: Group 1, finishing with abrasive paper; Group 2, finishing, airborne Al2O3 particle abrasion and silanization; Group 3, finishing, airborne particle abrasion, silicatization and silanization. After treatment, the blocks received cementation of resin composite cylinders with Panavia F (Kuraray Co. Ltd., Osaka, Japan and were submitted to the shear bond strength test in a universal testing machine. Results: The results were statistically analyzed (ANOVA and multiple comparison Student-Newman-Keuls test: Group 1 (9.66 ± 1.67 MPa < Group 2 (16.61 ± 3.38 MPa = Group 3 (19.23 ± 5.69 MPa, with p = 0.007. Conclusion: The structures of the In-Ceram YZ system (Vita Zahnfabrik, Bad Säckingen, Germany associated with Panavia F (Kuraray Co. Ltd., Osaka, Japan require previous etching to achieve greater bond strength between the ceramic and cement, and this treatment may be performed with airborne particle abrasion I or traditional silicatization, both followed by silanization.

  16. Effect of clearfil protect bond and transbond plus self-etch primer on shear bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    S Hamid Raji

    2011-01-01

    Conclusion: The shear bond strength of clearfil protect bond and transbond plus self-etch primer was enough for bonding the orthodontic brackets. The mode of failure of bonded brackets with these two self-etch primers is safe for enamel.

  17. Social-bond strength influences vocally mediated recruitment to mobbing.

    Science.gov (United States)

    Kern, Julie M; Radford, Andrew N

    2016-11-01

    Strong social bonds form between individuals in many group-living species, and these relationships can have important fitness benefits. When responding to vocalizations produced by groupmates, receivers are expected to adjust their behaviour depending on the nature of the bond they share with the signaller. Here we investigate whether the strength of the signaller-receiver social bond affects response to calls that attract others to help mob a predator. Using field-based playback experiments on a habituated population of wild dwarf mongooses (Helogale parvula), we first demonstrate that a particular vocalization given on detecting predatory snakes does act as a recruitment call; receivers were more likely to look, approach and engage in mobbing behaviour than in response to control close calls. We then show that individuals respond more strongly to these recruitment calls if they are from groupmates with whom they are more strongly bonded (those with whom they preferentially groom and forage). Our study, therefore, provides novel evidence about the anti-predator benefits of close bonds within social groups. © 2016 The Author(s).

  18. Shear bond strength of orthodontic brackets bonded with different self-etching adhesives.

    Science.gov (United States)

    Scougall Vilchis, Rogelio José; Yamamoto, Seigo; Kitai, Noriyuki; Yamamoto, Kohji

    2009-09-01

    The purpose of this study was to compare the shear bond strength (SBS) of orthodontic brackets bonded with 4 self-etching adhesives. A total of 175 extracted premolars were randomly divided into 5 groups (n = 35). Group I was the control, in which the enamel was etched with 37% phosphoric acid, and stainless steel brackets were bonded with Transbond XT (3M Unitek, Monrovia, Calif). In the remaining 4 groups, the enamel was conditioned with the following self-etching primers and adhesives: group II, Transbond Plus and Transbond XT (3M Unitek); group III, Clearfil Mega Bond FA and Kurasper F (Kuraray Medical, Tokyo, Japan); group IV, Primers A and B, and BeautyOrtho Bond (Shofu, Kyoto, Japan); and group V, AdheSE and Heliosit Orthodontic (Ivoclar Vivadent AG, Liechtenstein). The teeth were stored in distilled water at 37 degrees C for 24 hours and debonded with a universal testing machine. The adhesive remnant index (ARI) including enamel fracture score was also evaluated. Additionally, the conditioned enamel surfaces were observed under a scanning electron microscope. The SBS values of groups I (19.0 +/- 6.7 MPa) and II (16.6 +/- 7.3 MPa) were significantly higher than those of groups III (11.0 +/- 3.9 MPa), IV (10.1 +/- 3.7 MPa), and V (11.8 +/- 3.5 MPa). Fluoride-releasing adhesives (Kurasper F and BeautyOrtho Bond) showed clinically acceptable SBS values. Significant differences were found in the ARI and enamel fracture scores between groups I and II. The 4 self-etching adhesives yielded SBS values higher than the bond strength (5.9 to 7.8 MPa) suggested for routine clinical treatment, indicating that orthodontic brackets can be successfully bonded with any of these self-etching adhesives.

  19. Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials.

    Science.gov (United States)

    Hellak, Andreas; Ebeling, Jennifer; Schauseil, Michael; Stein, Steffen; Roggendorf, Matthias; Korbmacher-Steiner, Heike

    2016-01-01

    Objective. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of two self-etching no-mix adhesives (iBond ™ and Scotchbond ™ ) on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT ™ . Materials and Methods . A total of 270 surfaces (1 enamel and 8 restorative surfaces, n = 30) were randomly divided into three adhesive groups. In group 1 (control) brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2) and Scotchbond Universal adhesive (group 3) were used. The SBS was measured using a Zwicki 1120 ™ testing machine. The ARI and SBS were compared statistically using the Kruskal-Wallis test ( P ≤ 0.05). Results . Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions . Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain), with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended.

  20. Evaluation of the anti-cariogenic potential and bond strength to enamel of different fluoridated materials used for bracket bonding

    OpenAIRE

    SILVA, Sérgio Ricardo da; SILVA, Luciana Alves Herdy da; BASTING, Roberta Tarkany; LIMA-ARSATI, Ynara Bosco de Oliveira

    2017-01-01

    Abstract Objective To evaluate the in vitro and in situ anti-cariogenic potential and bond strength to enamel of materials containing fluoride (F), used for bracket bonding: Transbond XT (GT, negative control), Transbond Plus Color Change (GTF), Transbond-Self-Etching Primer (GSAF) and Vitremer (GV, positive control). Material and method In the in vitro study, the specimens were premolars with bonded brackets (n=12/group). After pH cycling, the F release, bond strength, fracture mode and pr...

  1. Bond strength of cementitious borehole plugs in welded tuff

    International Nuclear Information System (INIS)

    Akgun, H.; Daemen, J.J.K.

    1991-02-01

    Axial loads on plugs or seals in an underground repository due to gas, water pressures and temperature changes induced subsequent to waste and plug emplacement lead to shear stresses at the plug/rock contact. Therefore, the bond between the plug and rock is a critical element for the design and effectiveness of plugs in boreholes, shafts or tunnels. This study includes a systematic investigation of the bond strength of cementitious borehole plugs in welded tuff. Analytical and numerical analysis of borehole plug-rock stress transfer mechanics is performed. The interface strength and deformation are studied as a function of Young's modulus ratio of plug and rock, plug length and rock cylinder outside-to-inside radius ratio. The tensile stresses in and near an axially loaded plug are analyzed. The frictional interface strength of an axially loaded borehole plug, the effect of axial stress and lateral external stress, and thermal effects are also analyzed. Implications for plug design are discussed. The main conclusion is a strong recommendation to design friction plugs in shafts, drifts, tunnels or boreholes with a minimum length to diameter ratio of four. Such a geometrical design will reduce tensile stresses in the plug and in the host rock to a level which should minimize the risk of long-term deterioration caused by excessive tensile stresses. Push-out tests have been used to determine the bond strength by applying an axial load to cement plugs emplaced in boreholes in welded tuff cylinders. A total of 130 push-out tests have been performed as a function of borehole size, plug length, temperature, and degree of saturation of the host tuff. The use of four different borehole radii enables evaluation of size effects. 119 refs., 42 figs., 20 tabs

  2. Real space in situ bond energies: toward a consistent energetic definition of bond strength.

    Science.gov (United States)

    Menéndez-Crespo, Daniel; Costales, Aurora; Francisco, Evelio; Martin Pendas, Angel

    2018-04-14

    A rigorous definition of intrinsic bond strength based on the partitioning of a molecule into real space fragments is presented. Using the domains provided by the quantum theory of atoms in molecules (QTAIM) together with the interacting quantum atoms (IQA) energetic decomposition, we show how an in situ bond strength, matching all the requirements of an intrinsic bond energy, can be defined between each pair of fragments. Total atomization or fragmentation energies are shown to be equal to the sum of these in situ bond energies (ISBEs) if the energies of the fragments are measured with respect to their in-the-molecule state. These energies usually lie above the ground state of the isolated fragments by quantities identified with the standard fragment relaxation or deformation energies, which are also provided by the protocol. Deformation energies bridge dissociation energies with ISBEs, and can be dissected using well-known tools of real space theories of chemical bonding. Similarly, ISBEs can be partitioned into ionic and covalent contributions, and this feature adds to the chemical appeal of the procedure. All the energetic quantities examined are observable and amenable, in principle, to experimental determination. Several systems, exemplifying the role of each energetic term herein presented are used to show the power of the approach. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Microtensile bond strength of silorane-based composite specific adhesive system using different bonding strategies

    OpenAIRE

    Bastos, Laura Alves; Sousa, Ana Beatriz Silva; Drubi-Filho, Brahim; Panzeri Pires-de-Souza, Fernanda de Carvalho; Garcia, Lucas da Fonseca Roberti

    2014-01-01

    Objectives The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/S...

  4. Bond strength of two component injection moulded MID

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2006-01-01

    Most products of the future will require industrially adapted, cost effective production processes and on this issue two-component (2K) injection moulding is a potential candidate for MID manufacturing. MID based on 2k injection moulded plastic part with selectively metallised circuit tracks allows...... the two different plastic materials in the MID structure require good bonding between them. This paper finds suitable combinations of materials for MIDs from both bond strength and metallisation view-point. Plastic parts were made by two-shot injection moulding and the effects of some important process...... the integration of electrical and mechanical functionalities in a real 3D structure. If 2k injection moulding is applied with two polymers, of which one is plateable and the other is not, it will be possible to make 3D electrical structures directly on the component. To be applicable in the real engineering field...

  5. Equilibrium and non-equilibrium metal-ceramic interfaces

    International Nuclear Information System (INIS)

    Gao, Y.; Merkle, K.L.

    1992-01-01

    Metal-ceramic interfaces in thermodynamic equilibrium (Au/ZrO 2 ) and non-equilibrium (Au/MgO) have been studied by TEM and HREM. In the Au/ZrO 2 system, ZrO 2 precipitates formed by internal oxidation of a 7%Zr-Au alloy show a cubic ZrO 2 phase. It appears that formation of the cubic ZrO 2 is facilitated by alignment with the Au matrix. Most of the ZrO 2 precipitates have a perfect cube-on-cube orientation relationship with the Au matrix. The large number of interfacial steps observed in a short-time annealing experiment indicate that the precipitates are formed by the ledge growth mechanism. The lowest interfacial energy is indicated by the dominance of closed-packed [111] Au/ZrO 2 interfaces. In the Au/MgO system, composite films with small MgO smoke particles embedded in a Au matrix were prepared by a thin film technique. HREM observations show that most of the Au/MgO interfaces have a strong tendency to maintain a dense lattice structure across the interfaces irrespective of whether the interfaces are incoherent or semi-coherent. This paper reports that this indicates that there may be a relatively strong bond between MgO and Au

  6. Shear Bond Strength of Three Orthodontic Bonding Systems on Enamel and Restorative Materials

    Directory of Open Access Journals (Sweden)

    Andreas Hellak

    2016-01-01

    Full Text Available Objective. The aim of this in vitro study was to determine the shear bond strength (SBS and adhesive remnant index (ARI score of two self-etching no-mix adhesives (iBond™ and Scotchbond™ on different prosthetic surfaces and enamel, in comparison with the commonly used total etch system Transbond XT™. Materials and Methods. A total of 270 surfaces (1 enamel and 8 restorative surfaces, n=30 were randomly divided into three adhesive groups. In group 1 (control brackets were bonded with Transbond XT primer. In the experimental groups iBond adhesive (group 2 and Scotchbond Universal adhesive (group 3 were used. The SBS was measured using a Zwicki 1120™ testing machine. The ARI and SBS were compared statistically using the Kruskal–Wallis test (P≤0.05. Results. Significant differences in SBS and ARI were found between the control group and experimental groups. Conclusions. Transbond XT showed the highest SBS on human enamel. Scotchbond Universal on average provides the best bonding on all other types of surface (metal, composite, and porcelain, with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures on restorative materials in patients. If metal brackets have to be bonded to a metal surface, the use of a dual-curing resin is recommended.

  7. Shear bond strength of two bonding systems on dentin surfaces prepared with Er:YAG laser

    International Nuclear Information System (INIS)

    Dall'Magro, Eduardo

    2001-01-01

    The purpose of this study was to examine the shear bond strength of two bonding dentin systems, one 'one step' (Single Bond - 3M) and one 'self-etching' (Prompt-L-ESPE), when applied on dentin surfaces prepared with Er:YAG laser (2,94μm) that underwent ar not, acid etched. Forty one human molars just extracted were selected and after the cut with diamond disc and included in acrylic resin, resulting in 81 specimens (hemi crowns). After, the specimens were divided in one group treated with sand paper and another two groups treated with Er:YAG laser with 200 mJ and 250 mJ of energy and 2 Hz of frequency. Next, the prepared surfaces received three treatments with following application: 1) acid + Single Bond + Z 250 resin, 2) prompt-L-Pop + Z 250 resin, and 3) acid without, Single Bond + Z 250 resin. The Z 250 resin was applied and photopolymerized in increments on a Teflon matrix that belonged to an apparatus called 'Assembly Apparatus' machine producing cylinders of 3,5 mm of diameter and 5 mm of height. After these specimens were submitted to thermo cycling during 1 minute the 55 deg C and during 1 minute with 5 deg C with a total of 500 cycles for specimen, and the measures of shear bond strength were abstained using EMIC model DL 2000 rehearsed machine, with speed of 0,5 mm/min, measuring the final rupture tension (Mpa). The results showed an statistic superiority of 5% of probability level in dentin flattened with sandpaper and with laser using 200 mJ of energy with aspect to the ones flattened with laser using 250 mJ of energy. It was observed that using 'Single Bond' bonding dentin system the marks were statistically superior at 5% of probability with reference to the use of the Prompt-L-Pop adhesive system. So, it was concluded that Er:YAG Laser with 200 mJ of energy produced similar dentin cavity prepare than sandpaper and Single Bond seemed the best bonding agent system between restorative material and dentin. (author)

  8. Metal-ceramic alloys in dentistry: a review.

    Science.gov (United States)

    Roberts, Howard W; Berzins, David W; Moore, B Keith; Charlton, David G

    2009-02-01

    The purpose of this article is to review basic information about the alloys used for fabricating metal-ceramic restorations in dentistry. Their compositions, properties, advantages, and disadvantages are presented and compared. In addition to reviewing traditional noble-metal and base-metal metal-ceramic alloys, titanium and gold composite alloys are also discussed. A broad search of the published literature was performed using Medline to identify pertinent current articles on metal-ceramic alloys as well as articles providing a historical background about the development of these alloys. Textbooks, the internet, and manufacturers' literature were also used to supplement this information. The review discusses traditional as well as more recently-developed alloys and technologies used in dentistry for fabricating metal-ceramic restorations. Clear advantages and disadvantages for these alloy types are provided and discussed as well as the role that compositional variations have on the alloys' performance. This information should enable clinicians and technicians to easily identify the important physical properties of each type and their primary clinical indications. A number of alloys and metals are available for metal-ceramic use in dentistry. Each has its advantages and disadvantages, primarily based on its specific composition. Continuing research and development are resulting in the production of new technologies and products, giving clinicians even more choices in designing and fabricating metal-ceramic restorations.

  9. Effects of recycling and bonding agent application on bond strength of stainless steel orthodontic brackets.

    Science.gov (United States)

    Bahnasi, Faisal I; Abd-Rahman, Aida Na; Abu-Hassan, Mohame I

    2013-10-01

    1) to assess different methods of recycling orthodontic brackets, 2) to evaluate Shear Bond Strength (SBS) of (a) new, (b) recycled and (c) repeated recycled stainless steel brackets (i) with and (ii) without bracket base primer. A total of 180 extracted human premolar teeth and 180 premolar stainless steel brackets were used. One hundred teeth and 100 brackets were divided into five groups of 20-teeth each. Four methods of recycling orthodontic brackets were used in each of the first four groups while the last one (group V) was used as the control. Groups (I-V) were subjected to shear force within half an hour until the brackets debond. SBS was measured and the method showing the highest SBS was selected. A New group (VI) was recycled twice with the selected method. Six subgroups (1-6) were established; the primer was applied for three sub-groups, and the composite was applied for all brackets. Brackets were subjected to the same shear force, and SBS was measured for all sub-groups. There was a significant difference between the mean SBS of the sandblasting method and the means of SBS of each of the other three methods. There was however, no significant difference between the mean SBS of the new bracket and the mean SBS of recycled bracket using sandblasting. The mean SBS of all sub-groups were more than that recommended by Reynolds (17) in 1975. Brackets with primer showed slightly higher SBS compared to those of brackets without bonding agent. To decrease cost, sandblasted recycled orthodontic brackets can be used as an alternative to new brackets. It is recommended to apply a bonding agent on the bracket base to provide greater bond strength. Key words:Recycled bracket, shear bond strength, sandblasting, stainless steel orthodontic bracket.

  10. Effects of recycling and bonding agent application on bond strength of stainless steel orthodontic brackets

    Science.gov (United States)

    Bahnasi, Faisal I.; Abu-Hassan, Mohame I.

    2013-01-01

    Objectives: 1) to assess different methods of recycling orthodontic brackets, 2) to evaluate Shear Bond Strength (SBS) of (a) new, (b) recycled and (c) repeated recycled stainless steel brackets (i) with and (ii) without bracket base primer. Study Design: A total of 180 extracted human premolar teeth and 180 premolar stainless steel brackets were used. One hundred teeth and 100 brackets were divided into five groups of 20-teeth each. Four methods of recycling orthodontic brackets were used in each of the first four groups while the last one (group V) was used as the control. Groups (I-V) were subjected to shear force within half an hour until the brackets debond. SBS was measured and the method showing the highest SBS was selected. A New group (VI) was recycled twice with the selected method. Six subgroups (1-6) were established; the primer was applied for three sub-groups, and the composite was applied for all brackets. Brackets were subjected to the same shear force, and SBS was measured for all sub-groups. Results: There was a significant difference between the mean SBS of the sandblasting method and the means of SBS of each of the other three methods. There was however, no significant difference between the mean SBS of the new bracket and the mean SBS of recycled bracket using sandblasting. The mean SBS of all sub-groups were more than that recommended by Reynolds (17) in 1975. Brackets with primer showed slightly higher SBS compared to those of brackets without bonding agent. Conclusion: To decrease cost, sandblasted recycled orthodontic brackets can be used as an alternative to new brackets. It is recommended to apply a bonding agent on the bracket base to provide greater bond strength. Key words:Recycled bracket, shear bond strength, sandblasting, stainless steel orthodontic bracket. PMID:24455081

  11. A comparison of shear bond strength of orthodontic brackets bonded with four different orthodontic adhesives

    Science.gov (United States)

    Sharma, Sudhir; Tandon, Pradeep; Nagar, Amit; Singh, Gyan P; Singh, Alka; Chugh, Vinay K

    2014-01-01

    Objectives: The objective of this study is to compare the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets bonded with four different orthodontic adhesives. Materials and Methods: Eighty newly extracted premolars were bonded to 0.022 SS brackets (Ormco, Scafati, Italy) and equally divided into four groups based on adhesive used: (1) Rely-a-Bond (self-cure adhesive, Reliance Orthodontic Product, Inc., Illinois, USA), (2) Transbond XT (light-cure adhesive, 3M Unitek, CA, USA), (3) Transbond Plus (sixth generation self-etch primer, 3M Unitek, CA, USA) with Transbond XT (4) Xeno V (seventh generation self-etch primer, Dentsply, Konstanz, Germany) with Xeno Ortho (light-cure adhesive, Dentsply, Konstanz, Germany) adhesive. Brackets were debonded with a universal testing machine (Model No. 3382 Instron Corp., Canton, Mass, USA). The adhesive remnant index (ARI) was recordedIn addition, the conditioned enamel surfaces were observed under a scanning electron microscope (SEM). Results: Transbond XT (15.49 MPa) attained the highest bond strength. Self-etching adhesives (Xeno V, 13.51 MPa; Transbond Plus, 11.57 MPa) showed clinically acceptable SBS values and almost clean enamel surface after debonding. The analysis of variance (F = 11.85, P adhesives left on the tooth) to be the most prevalent in Transbond XT (40%), followed by Rely-a-Bond (30%), Transbond Plus with Transbond XT (15%), and Xeno V with Xeno Ortho (10%). Under SEM, enamel surfaces after debonding of the brackets appeared porous when an acid-etching process was performed on the surfaces of Rely-a-Bond and Transbond XT, whereas with self-etching primers enamel presented smooth and almost clean surfaces (Transbond Plus and Xeno V group). Conclusion: All adhesives yielded SBS values higher than the recommended bond strength (5.9-7–8 MPa), Seventh generation self-etching primer Xeno V with Xeno Ortho showed clinically acceptable SBS and the least amount of residual adhesive left on the

  12. Effects of recycling and bonding agent application on bond strength of stainless steel orthodontic brackets

    OpenAIRE

    Bahnasi, Faisal I.; Abd-Rahman, Aida NA.; Abu-Hassan, Mohame I.

    2013-01-01

    Objectives: 1) to assess different methods of recycling orthodontic brackets, 2) to evaluate Shear Bond Strength (SBS) of (a) new, (b) recycled and (c) repeated recycled stainless steel brackets (i) with and (ii) without bracket base primer. Study Design: A total of 180 extracted human premolar teeth and 180 premolar stainless steel brackets were used. One hundred teeth and 100 brackets were divided into five groups of 20-teeth each. Four methods of recycling orthodontic brackets were used in...

  13. Bond Strength of Resin Cements to Dentin Using New Universal Bonding Agents

    Science.gov (United States)

    2015-06-30

    and acidic simplified adhesives is a well-studied phenomenon (Kanehira et al., 2006). A chemical incompatibility may occur in the oxygen-inhibited...not completely eliminate this incompatibility (Tay et al., 2003). Recently, new “universal adhesives ” have been introduced. These universal...potential incompatibilities with self-curing resin materials. Low bond strength between self-curing resin materials and acidic simplified adhesives is

  14. Enamel shear bond strength of two orthodontic self-etching bonding systems compared to Transbond™ XT.

    Science.gov (United States)

    Hellak, Andreas; Rusdea, Patrick; Schauseil, Michael; Stein, Steffen; Korbmacher-Steiner, Heike Maria

    2016-11-01

    The aim of this in vitro study was to compare the shear bond strength (SBS) and Adhesive Remnant Index (ARI) scores of two self-etching no-mix adhesives (Prompt L-Pop™ and Scotchbond™) for orthodontic appliances to the commonly used total etch system Transbond XT™ (in combination with phosphoric acid). In all, 60 human premolars were randomly divided into three groups of 20 specimens each. In group 1 (control), brackets were bonded with Transbond™ XT primer. Prompt L-Pop™ (group 2) and Scotchbond™ Universal (group 3) were used in the experimental groups. Lower premolar brackets were bonded by light curing the adhesive. After 24 h of storage, the shear bond strength (SBS) was measured using a Zwicki 1120 testing machine. The adhesive remnant index (ARI) was determined under 10× magnification. The Kruskal-Wallis test was used to statistically compare the SBS and the ARI scores. No significant differences in the SBS between any of the experimental groups were detected (group 1: 15.49 ± 3.28 MPa; group 2: 13.89 ± 4.95 MPa; group 3: 14.35 ± 3.56 MPa; p = 0.489), nor were there any significant differences in the ARI scores (p = 0.368). Using the two self-etching no-mix adhesives (Prompt L-Pop™ and Scotchbond™) for orthodontic appliances does not affect either the SBS or ARI scores in comparison with the commonly used total-etch system Transbond™ XT. In addition, Scotchbond™ Universal supports bonding on all types of surfaces (enamel, metal, composite, and porcelain) with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures.

  15. Microtensile bond strength of silorane-based composite specific adhesive system using different bonding strategies.

    Science.gov (United States)

    Bastos, Laura Alves; Sousa, Ana Beatriz Silva; Drubi-Filho, Brahim; Panzeri Pires-de-Souza, Fernanda de Carvalho; Garcia, Lucas da Fonseca Roberti

    2015-02-01

    The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/Silorane and Silorane groups). Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE) were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray), with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups), or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE) (Three-step/Methacrylate group) (n = 6). The restored teeth were sectioned into stick-shaped test specimens (1.0 × 1.0 mm), and coupled to a universal test machine (0.5 mm/min) to perform microtensile testing. Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p adhesive system to dentin.

  16. Comparative evaluation of shear bond strength of metallic brackets bonded with two different bonding agents under dry conditions and with saliva contamination.

    Science.gov (United States)

    Khanehmasjedi, Mashallah; Naseri, Mohammad Ali; Khanehmasjedi, Samaneh; Basir, Leila

    2017-02-01

    This study compared the shear bond strength of metallic brackets bonded with Single Bond and Assure bonding agents under dry and saliva-contamination conditions. Sixty sound premolar teeth were selected, and stainless-steel brackets were bonded on enamel surfaces with Single Bond and Assure bonding agents under dry condition or with saliva contamination. Shear bond strength values of brackets were measured in a universal testing machine. The adhesive remnant index scores were determined after debonding of the brackets under a stereomicroscope. One-way analysis of variance (ANOVA) was used to analyze bond strength. Two-by-two comparisons were made with post hoc Tukey tests (pbrackets to tooth structure were 9.29±8.56 MPa and 21.25±8.93 MPa with the use of Assure resin bonding agent under saliva-contamination and dry conditions, respectively. These values were 10.13±6.69 MPa and 14.09±6.6 MPa, respectively, under the same conditions with the use of Single Bond adhesive. Contamination with saliva resulted in a significant decrease in the bond strength of brackets to tooth structure with the application of Assure adhesive resin (pbrackets to tooth structures. Contamination with saliva significantly decreased the bond strength of Assure bonding agent compared with dry conditions. Copyright © 2016. Published by Elsevier Taiwan LLC.

  17. Comparison of the tensile bond strength of high-noble, noble, and base metal alloys bonded to enamel.

    Science.gov (United States)

    Sen, D; Nayir, E; Pamuk, S

    2000-11-01

    Although the bond strengths of various resin composite luting materials have been reported in the literature, the evaluation of these systems with various cast alloys of different compositions has not been completely clarified. To evaluate the tensile bond strength of sandblasted high-noble, noble, and base metal alloys bonded to etched enamel by 2 different bonding agents of different chemical composition: Panavia-Ex (BIS-GMA) and Super-Bond (4-META acrylic). Flat enamel surfaces were prepared on buccal surfaces of 60 extracted noncarious human incisors. Teeth were divided into 3 groups of 20 each. Twenty circular disks of 5 mm diameter were prepared for casting for each group. Group I was cast with a high-noble, group II with a noble, and group III with a base metal alloy. The surfaces of the disks were sandblasted with 250 microm Al(2)O(3). Ten disks of each group were bonded to exposed enamel surfaces with Super-Bond and 10 disks with Panavia-Ex as recommended by the manufacturer. The tensile bond strength was measured with an Instron universal testing machine with a crosshead speed of 0.5 mm/min until failure occurred. Two-way ANOVA was used to evaluate the results. The differences in bond strengths of Super-Bond and Panavia-Ex with different alloys were not significant. The highest bond strengths were obtained in base metal alloys, followed by noble and high-noble alloys. These results were significant. Panavia-Ex and Super-Bond exhibited comparable tensile bond strengths. For both luting agents, the highest bond strengths were achieved with base metal alloys and the lowest with high-noble alloys.

  18. Relationship between surface area for adhesion and tensile bond strength--evaluation of a micro-tensile bond test.

    Science.gov (United States)

    Sano, H; Shono, T; Sonoda, H; Takatsu, T; Ciucchi, B; Carvalho, R; Pashley, D H

    1994-07-01

    The purpose of this study was to test the null hypothesis that there is no relationship between the bonded surface area of dentin and the tensile strength of adhesive materials. The enamel was removed from the occlusal surface of extracted human third molars, and the entire flat surface was covered with resin composite bonded to the dentin to form a flat resin composite crown. Twenty-four hours later, the bonded specimens were sectioned parallel to the long axis of the tooth into 10-20 thin sections whose upper part was composed of resin composite with the lower half being dentin. These small sections were trimmed using a high speed diamond bur into an hourglass shape with the narrowest portion at the bonded interface. Surface area was varied by altering the specimen thickness and width. Tensile bond strength was measured using custom-made grips in a universal testing machine. Tensile bond strength was inversely related to bonded surface area. At surface areas below 0.4 mm2, the tensile bond strengths were about 55 MPa for Clearfil Liner Bond 2 (Kuraray Co., Ltd.), 38 MPa for Scotchbond MP (3M Dental Products), and 20 MPa for Vitremer (3M Dental Products). At these small surface areas all of the bond failures were adhesive in nature. This new method permits measurement of high bond strengths without cohesive failure of dentin. It also permits multiple measurements to be made within a single tooth.

  19. A structural bond strength model for glass durability

    International Nuclear Information System (INIS)

    Feng, Xiangdong; Metzger, T.B.

    1996-01-01

    A glass durability model, structural bond strength (SBS) model was developed to correlate glass durability with its composition. This model assumes that the strengths of the bonds between cations and oxygens and the structural roles of the individual elements in the glass arc the predominant factors controlling the composition dependence of the chemical durability of glasses. The structural roles of oxides in glass are classified as network formers, network breakers, and intermediates. The structural roles of the oxides depend upon glass composition and the redox state of oxides. Al 2 O 3 , ZrO 2 , Fe 2 O 3 , and B 2 O 3 are assigned as network formers only when there are sufficient alkalis to bind with these oxides. CaO can also improve durability by sharing non-bridging oxygen with alkalis, relieving SiO 2 from alkalis. The percolation phenomenon in glass is also taken into account. The SBS model is applied to correlate the 7-day product consistency test durability of 42 low-level waste glasses with their composition with an R 2 of 0.87, which is better than 0.81 obtained with an eight-coefficient empirical first-order mixture model on the same data set

  20. EFFECT OF SURFACE CONDTIONINGON BOND STRENGTH TO ENAMEL AND DENTIN

    Directory of Open Access Journals (Sweden)

    M MOUSAVINASAB

    2002-09-01

    Full Text Available Introduction. Compoglass is a trade mark of dental compomers and because of its partially resinus structure, surface conditioning of dental surfaces is needed for a better bonding process. In this study, the effect of enamel and dentin conditioning procedure on shear bond strength (SBS of compoglass to tooth surfaces was studied. Methods. four groups each one including 11 sound premolars were chosen and their surfaces were prepared as following groups: group1, unconitioned dentin; group 2, dentin conditioning with phosphoric acid 35%; group 3, dentin conditioning with polyacrylic acid 20% group 4, unconditioning enamel; group 5, enamel conditioning with phosphoric acid 35%; and group 6, enamel conditioning with polyacrylic acid 20%. Compoglass was bonded to prepared surfaces and after fixation of the samples in acrylic molds, all samples were tested under shear force of instron testing machine at a rate of 1 mm/min speed. Results. The mean SBS obtained in these 6 groups were 6.207, 8.057, 10.146, 25.939 and 11.827 mpa. the mode of fracture also studied using a streomicroscope. Statistical analysis of the results showed that the maximum SBS obtained in group 5 and the lowest SBS about 6.207 mpa obtained in group 1. Despite increase in SBS group 2 and 3, there was no statistical differncies between group 1, 2 and 3. Discussion. Based on results of this study, conditioning of enamel and dentin surface due to improve SBS is recommeneded.

  1. Effect of Sandblasting on Shear Bond Strength Composite Resin Veneer

    Directory of Open Access Journals (Sweden)

    Octarina Octarina

    2013-07-01

    Full Text Available Attachment between restoration and enamel surface in indirect resin composite veneer restoration (IRCV is obtained using multi-step (MS resin cement. Recently, a one step self-adhesive dual-cured resin cement (SADRC was introduced. Objective: To determine the effect of sandblasting on shear bond strength (SBS of IRCV to enamel using MS resin cement and SADRC. Methods: Forty specimens of buccal surface of enamel human were light-cured in Solidilite chamber and were divided into two groups: IRCV without sandblasting (n=20 and with sandblasting for 10 seconds (n=20 and then bonded to enamel using MS (n=10 and SADRC (n=10, respectively. After 24h SBS of specimens were tested using a Universal Testing Machine. Data were analyzed statistically by one-way ANOVA. Results: The average SBS value of IRCV without SB and bonded with MS was 18.95+7.80MPa and MS with SB was 19.30+ SB (4.85+2.12MPa and SADRC with SB (9.57+3.45MPa(p<0.05. Conclusion: increased SBS VIRK to enamel using MS resin cement than SADRC.  

  2. A critical Examination of the Phenomenon of Bonding Area - Bonding Strength Interplay in Powder Tableting.

    Science.gov (United States)

    Osei-Yeboah, Frederick; Chang, Shao-Yu; Sun, Changquan Calvin

    2016-05-01

    Although the bonding area (BA) and bonding strength (BS) interplay is used to explain complex tableting behaviors, it has never been experimentally proven. The purpose of this study is to unambiguously establish the distinct contributions of each by decoupling the contributions from BA and BS. To modulate BA, a Soluplus® powder was compressed into tablets at different temperatures and then broken following equilibration at 25°C. To modulate BS, tablets were equilibrated at different temperatures. To simultaneously modulate BA and BS, both powder compression and tablet breaking test were carried out at different temperatures. Lower tablet tensile strength is observed when the powder is compressed at a lower temperature but broken at 25°C. This is consistent with the increased resistance to polymer deformation at lower temperatures. When equilibrated at different temperatures, the tensile strength of tablets prepared under identical conditions increases with decreasing storage temperature, indicating that BS is higher at a lower temperature. When powder compression and tablet breaking are carried out at the same temperature, the profile with a maximum tensile strength at 4°C is observed due to the BA-BS interplay. By systematically varying temperature during tablet compression and breaking, we have experimentally demonstrated the phenomenon of BA-BS interplay in tableting.

  3. Efficacy of microtensile versus microshear bond testing for evaluation of bond strength of dental adhesive systems to enamel

    NARCIS (Netherlands)

    El Zohairy, A.A.; Saber, M.H.; Abdalla, A.I.; Feilzer, A.J.

    2010-01-01

    Objective The aim of the study was to evaluate the efficacy of the microtensile bond test (μTBS) and the microshear bond test (μSBS) in ranking four dental adhesives according to bond strength to enamel and identify the modes of failure involved. Materials and methods Forty-four caries-free human

  4. A Unique Method to Describe the Bonding Strength in a Bonded Solid–Solid Interface by Contact Acoustic Nonlinearity

    International Nuclear Information System (INIS)

    Jian-Jun, Chen; De, Zhang; Yi-Wei, Mao; Jian-Chun, Cheng

    2009-01-01

    We present a unique method to describe the bonding strength at a bonded solid–solid interface in a multilayered composite material by contact acoustic nonlinearity (CAN) parameter. A CAN model on the bonded solid–solid interface is depicted. It can be seen from the model that CAN parameter is very sensitive to the bonding strength at the interface. When an incident focusing acoustic longitudinal wave scans the interface in two dimensions, the transmitted wave can be used to extract CAN parameter. The contour of the bonding strength for a sample is obtained by CAN parameter. The results show that the region with weak bonding strength can be easily distinguished from the contour

  5. Bond strength of self-etch adhesives after saliva contamination at different application steps.

    Science.gov (United States)

    Cobanoglu, N; Unlu, N; Ozer, F F; Blatz, M B

    2013-01-01

    This study evaluated and compared the effect of saliva contamination and possible decontamination methods on bond strengths of two self-etching adhesive systems (Clearfil SE Bond [CSE], Optibond Solo Plus SE [OSE]). Flat occlusal dentin surfaces were created on 180 extracted human molar teeth. The two bonding systems and corresponding composite resins (Clearfil AP-X, Kerr Point 4) were bonded to the dentin under six surface conditions (n=15/group): group 1 (control): primer/bonding/composite; group 2: saliva/drying/primer/bonding/composite; group 3: primer/saliva/rinsing/drying/primer/bonding/composite; group 4: primer/saliva/rinsing/drying/bonding/composite; group 5: primer/bonding (cured)/saliva/rinsing/drying/primer/bonding/composite; group 6: primer/bonding (cured)/saliva/removing contaminated layer with a bur/rinsing/drying/primer/bonding/composite. Shear bond strength was tested after specimens were stored in distilled water at 37°C for 24 hours. One-way analysis of variance and Tukey post hoc tests were used for statistical analyses. For CSE, groups 2, 3, and 4 and for OSE, groups 6, 2, and 4 showed significantly lower bond strengths than the control group (pcontamination occurred after light polymerization of the bonding agent, repeating the bonding procedure recovered the bonding capacity of both self-etch adhesives. However, saliva contamination before or after primer application negatively affected their bond strength.

  6. Evaluating resin-enamel bonds by microshear and microtensile bond strength tests: effects of composite resin

    Directory of Open Access Journals (Sweden)

    Andrea Mello de Andrade

    2010-12-01

    Full Text Available OBJECTIVES: The aims of this study were to evaluate the effect of resin composite (Filtek Z250 and Filtek Flow Z350 and adhesive system [(Solobond Plus, Futurabond NR (VOCO and Adper Single Bond (3M ESPE] on the microtensile (μTBS and microshear bond strength (μSBS tests on enamel, and to correlate the bond strength means between them. MATERIAL AND METHODS: Thirty-six extracted human molars were sectioned to obtain two tooth halves: one for μTBS and the other one for μSBS. Adhesive systems and resin composites were applied to the enamel ground surfaces and light-cured. After storage (37(0C/24 h specimens were stressed (0.5 mm/min. Fracture modes were analyzed under scanning electron microscopy. The data were analyzed using two-way ANOVA and Tukey's test (α=0.05. RESULTS: The correlation between tests was estimated with Pearson's product-moment correlation statistics (α =0.05. For both tests only the main factor resin composite was statistically significant (p<0.05. The correlation test detected a positive (r=0.91 and significant (p=0.01 correlation between the tests. CONCLUSIONS: The results were more influenced by the resin type than by the adhesives. Both microbond tests seem to be positive and linearly correlated and can therefore lead to similar conclusions.

  7. Evaluating resin-enamel bonds by microshear and microtensile bond strength tests: effects of composite resin

    Science.gov (United States)

    de ANDRADE, Andrea Mello; MOURA, Sandra Kiss; REIS, Alessandra; LOGUERCIO, Alessandro Dourado; GARCIA, Eugenio Jose; GRANDE, Rosa Helena Miranda

    2010-01-01

    Objectives The aims of this study were to evaluate the effect of resin composite (Filtek Z250 and Filtek Flow Z350) and adhesive system [(Solobond Plus, Futurabond NR (VOCO) and Adper Single Bond (3M ESPE)] on the microtensile (µTBS) and microshear bond strength (µSBS) tests on enamel, and to correlate the bond strength means between them. Material and methods Thirty-six extracted human molars were sectioned to obtain two tooth halves: one for µTBS and the other one for µSBS. Adhesive systems and resin composites were applied to the enamel ground surfaces and light-cured. After storage (37ºC/24 h) specimens were stressed (0.5 mm/ min). Fracture modes were analyzed under scanning electron microscopy. The data were analyzed using two-way ANOVA and Tukey's test (α=0.05). Results The correlation between tests was estimated with Pearson's product-moment correlation statistics (α =0.05). For both tests only the main factor resin composite was statistically significant (padhesives. Both microbond tests seem to be positive and linearly correlated and can therefore lead to similar conclusions. PMID:21308290

  8. Investigation of Bond Strength in Centrifugal Lining of Babbitt on Cast Iron

    Science.gov (United States)

    Diouf, Papa; Jones, Alan

    2010-03-01

    The quality of the bond between Babbitt metal and a cast iron substrate was evaluated for centrifugal casting and static casting using the Chalmers bond strength method and scanning electron microscopy (SEM). The effect of three different centrifugal casting parameters, the speed of revolution, the pouring rate, and the cooling rate, was investigated. The bond strength and the microstructure at the bond interface were predominantly affected by the cooling rate, with a fast cooling rate resulting in better properties. The speed of revolution and the pouring rate only had a small effect on the bond strength, with faster revolution and faster pouring rate resulting in slightly better bonds.

  9. Evaluation of fracture toughness for metal/ceramics composite materials by means of miniaturized specimen technique

    International Nuclear Information System (INIS)

    Saito, Masahiro; Takahashi, Hideaki; Jeong, Hee-Don; Kawasaki, Akira; Watanabe, Ryuzo

    1991-01-01

    In order to evaluate fracture strength for Y 2 O 3 -ZrO 2 , 3 mol% Y 2 O 3 -ZrO 2 (PSZ)/SUS 304 composite materials, Macor as a machinable ceramics and comercially available ceramics (SiC, Si 3 N 4 , PSZ, Al 2 O 3 ), fracture toughness tests were carried out by use of RCT or bending specimens. On the other hand, the fracture strength of these materials was evaluated and inspected the correlation between fracture toughness and fracture stress of small punch (SP) or modified small punch (MSP) test data to predict the fracture toughness value by using miniaturized specimens. Characteristic of the MSP testing method is the ability to evaluate elastic modulus (Young's modulus), fracture strength, yield strength, fracture strain, and fracture energy, etc., with high accuracy and good reproducibility for brittle materials. For a series of metal/ ceramics composites which from ductile to brittle, this paper clarified clear the applicable range for SP and MSP testing methods, which suggested that the simultaneous use of SP and MSP test methods can evaluate the fracture strength of metal/ ceramics composites. (author)

  10. Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-filled Composites

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Ahmad Akhoundi

    2013-01-01

    Full Text Available Objectives: The purpose of this study was to evaluate the shear bond strength (SBS of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI was also evaluated using a stereomicroscope. Results: AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91± 2.13 and Filtek TM Supreme XT (6.04± 2.01. Statistical analysis revealed a significant difference between groups II and III (P 0.05. Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Conclusion: Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

  11. Evaluation of shear bond strength of orthodontic brackets bonded with nano-filled composites.

    Science.gov (United States)

    Chalipa, Javad; Akhondi, Mohammad Sadegh Ahmad; Arab, Sepideh; Kharrazifard, Mohammad Javad; Ahmadyar, Maryam

    2013-09-01

    The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel) were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI) was also evaluated using a stereomicroscope. AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91±2.13) and Filtek TM Supreme XT (6.04±2.01). Statistical analysis revealed a significant difference between groups II and III (P 0.05). Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

  12. Improved bonding strength of bioactive cermet Cold Gas Spray coatings.

    Science.gov (United States)

    Gardon, M; Concustell, A; Dosta, S; Cinca, N; Cano, I G; Guilemany, J M

    2014-12-01

    The fabrication of cermet biocompatible coatings by means Cold Gas Spray (CGS) provides prosthesis with outstanding mechanical properties and the required composition for enhancing the bioactivity of prosthetic materials. In this study, hydroxyapatite/Titanium coatings were deposited by means of CGS technology onto titanium alloy substrates with the aim of building-up well-bonded homogeneous coatings. Powders were blended in different percentages and sprayed; as long as the amount of hydroxyapatite in the feedstock increased, the quality of the coating was reduced. Besides, the relation between the particle size distribution of ceramic and metallic particles is of significant consideration. Plastic deformation of titanium particles at the impact eased the anchoring of hard hydroxyapatite particles present at the top surface of the coating, which assures the looked-for interaction with the cells. Coatings were immersed in Hank's solution for 1, 4 and 7 days; bonding strength value was above 60 MPa even after 7 days, which enhances common results of HAp coatings obtained by conventional thermal spray technologies. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Fatigue strength of a single lap joint SPR-bonded

    International Nuclear Information System (INIS)

    Di Franco, G.; Fratini, L.; Pasta, A.

    2011-01-01

    In the last years, hybrid joints, meaning with this the joints which consist in combining a traditional mechanical joint to a layer of adhesive, are gradually attracting the attention of various sectors of the construction of vehicles and transportation industries, for their better performance compared to just mechanical joints (self-piercing riveting SPR, riveting, and so on) or just to bonded joints.The paper investigates the fatigue behavior of a single lap joint self-piercing riveted (SPR) and bonded throughout fatigue tests. The considered geometric configuration allowed the use of two rivets placed longitudinally; an epoxy resin was used as adhesive. In the first part of the work static characterization of the joints was carried out through tensile tests. Then fatigue tests were made with the application of different levels of load. The fatigue curves were also obtained at the varying the distance between the two rivets in order to better assess the joint strength for a given length of overlap.

  14. Shear bond strength of a new one-bottle dentin adhesive.

    Science.gov (United States)

    Swift, E J; Bayne, S C

    1997-08-01

    To test the shear bond strength of a new adhesive, 3M Single Bond, to dentin surfaces containing different degrees of moisture. Two commercially available one-bottle adhesives (Prime & Bond, One-Step) and a conventional three-step system (Scotchbond Multi-Purpose Plus) were included for comparison. 120 bovine teeth were embedded in acrylic and the labial surfaces were polished to 600 grit to create standardized dentin surfaces for testing. Resin composite was bonded to dentin using a gelatin capsule technique. Four adhesive systems were evaluated with three different degrees of surface moisture (moist, wet, and overwet). Shear bond strengths of adhesives to dentin were determined using a universal testing machine and analyzed by ANOVA and Tukey's post hoc tests. Single Bond had mean shear bond strengths of 19.2, 23.2 and 20.3 MPa to moist, wet, and overwet dentin, respectively. Bond strengths of the three-component system Scotchbond Multi-Purpose Plus ranged from 23.1 to 25.3 MPa, but were not significantly higher than the values for Single Bond. Prime & Bond had bond strengths similar to those of Single Bond, but One-Step had significantly lower bond strengths (P < 0.05) in the wet and overwet conditions.

  15. Effect of Curing Direction on Microtensile Bond Strength of Fifth and Sixth Generation Dental Adhesives

    Directory of Open Access Journals (Sweden)

    Ali Nadaf

    2012-09-01

    Full Text Available Background and Aims: Composite restorative materials and dental adhesives are usually cured with light sources. The light direction may influence the bond strength of dental adhesives. The aim of this study was to evaluate the effect of light direction on the microtensile bond strength of fifth and sixth generation dental adhesives.Materials and Methods: Prime & Bond NT and Clearfil SE bond were used with different light directions.Sixty human incisor teeth were divided into 4 groups (n=15. In groups A and C, Clearfil SE bond with light curing direction from buccal was used for bonding a composite resin to dentin. In groups B and D, Prime & Bond NT with light curing direction from composite was used. After thermocycling the specimens were subjected to tensile force until debonding occurred and values for microtensile bond strength were recorded. The data were analyzed using two-way ANOVA and Tukey post hoc test.Results: The findings showed that the bond strength of Clearfil SE bond was significantly higher than that of Prime&Bond NT (P<0.001. There was no significant difference between light curing directions (P=0.132.Conclusion: Light curing direction did not have significant effect on the bond strength. Sixth generation adhesives was more successful than fifth generation in terms of bond strength to dentin.

  16. Tensile bond strength of hydroxyethyl methacrylate dentin bonding agent on dentin surface at various drying techniques

    Directory of Open Access Journals (Sweden)

    Kun Ismiyatin

    2010-06-01

    Full Text Available Background: There are several dentin surface drying techniques to provide a perfect resin penetration on dentin. There are two techniques which will be compared in this study. The first technique was by rubbing dentin surface gently using cotton pellet twice, this technique is called blot dry technique. The second technique is by air blowing dentin surface for one second and continued by rubbing dentin surface gently using moist cotton. Purpose: This experiment was aimed to examine the best dentin surface drying techniques after 37% phosphoric acid etching to obtain the optimum tensile bond strength between hydroxyethyl methacrylate (HEMA and dentin surface. Method: Bovine teeth was prepared flat to obtain the dentin surface and than was etched using 37% phosphoric acid for 15 seconds. After etching the dentin was cleaned using 20 cc plain water and dried with blot dry techniques (group I, or dried with air blow for one second (group II, or dried with air blow for one second, and continued with rubbing gently using moist cotton pellet (group III, and without any drying as control group (group IV. After these drying, the dentin surfaces were applied with resin dentin bonding agent and put into plunger facing the composite mould. The antagonist plunger was filled with composite resin. After 24 hours, therefore bond strength was measured using Autograph. Result: Data obtained was analyzed using One-Way ANOVA with 95% confidence level and continued with LSD test on p≤0.05. The result showed that the highest tensile bond strength was on group I, while the lowest on group IV. Group II and IV, III and IV, II and III did not show signigicant difference (p>0.05. Conclusion: Dentin surface drying techniques through gentle rubbing using cotton pellet twice (blot dry technique gave the greatest tensile bond strength.Latar belakang masalah: Tehnik pengeringan permukaan dentin agar resin dapat penetrasi dengan sempurna adalah dengan cara pengusapan secara

  17. Comparison of shear bond strength between unfilled resin to dry enamel and dentin bonding to moist and dry enamel

    Directory of Open Access Journals (Sweden)

    Yasini E.

    2005-05-01

    Full Text Available Statement of Problem: The use of dentine bondings on enamel and dentin in total etch protocols has recently become popular. Unfilled resin is hydrophobic and dentin bonding is hydrophilic in nature. This chemical difference could be effective in enamel bonding process. Purpose: The aim of this study was to compare the shear bond strength of unfilled resin to dry enamel and dentin bonding to dry and moist enamel. Materials and Methods: In this experimental study, a total of 30 incisor teeth were used. The specimens were randomly assigned to three groups of 10. 37% phosphoric acid etchant was applied to the enamel surfaces in each group for 15 seconds, rinsed with water for 20 seconds and dried for 20 seconds with compressed air in groups one and two. After conditioning, group 1 received unfilled resin (Margin Bond, Colten and group 2 received dentin bonding (Single Bond, 3M and in group 3 after conditioning and rinsing with water, a layer of dentin bonding (Single Bond was applied on wet enamel. The enamel and dentin bonding were light cured for 20 seconds. A ring mold 3.5 mm in diameter and 2 mm height was placed over the specimens to receive the composite filling material (Z100, 3M. The composite was cured for 40 seconds. The specimens were thermocycled and shear bond strengths were determined using an Instron Universal Testing Machine. The findings were analyzed by ANOVA One-Way and Tukey HSD tests. Results: Shear bond strength of dentin bonding to dry enamel was significantly less than unfilled resin to dry enamel (P<0.05. There was no significant difference between the bond strength of dentin bonding to moist and dry enamel. In addition bond strength of dentin bonding to wet enamel was not significantly different from unfilled resin to dry enamel. Conclusion: Based on the findings of this study, it is suggested that enamel surface should remain slightly moist after etching before bonding with single bond but when using unfilled resin, the

  18. Effect of a New Surface Treatment Solution on the Bond Strength of Composite to Enamel

    Science.gov (United States)

    2016-06-01

    Bond Strength of Composite to Enamel " is appropriately acknowledged and, beyond brief excerpts, is with the permission of the copyright owner...Solution on the Bond Strength of Composite to Enamel ABSTRACT Clean & Boost (Apex Dental Materials) is a novel surface treatment solution...designed to be used in place of phosphoric acid to increase the bond strength of self-etch adhesives to enamel and more effectively remove contaminants

  19. Influence of disinfectant solutions on the tensile bond strength of a fourth generation dentin bonding agent

    Directory of Open Access Journals (Sweden)

    BOCANGEL Jorge Saldivar

    2000-01-01

    Full Text Available The purpose of the present study was to evaluate the influence of different disinfectant solutions on the tensile bond strength of a fourth generation dentin bonding agent. Forty non carious human molars were selected. Teeth were embedded in acrylic resin and ground until the exposure of a flat superficial dentin surface. Teeth were randomly divided in 4 groups and treated as follows: Group 1 - 2.5% NaOCl for 40 seconds; Group 2 - 2% chlorhexidine for 40 seconds; Group 3 - 1.23% acidulated fluoride for 4 minutes; and Group 4 - control (without disinfectant solution. Following treatments, Scotchbond Multipurpose Plus® (3M was used according to the manufacturer's instructions. After that, the test specimens were built with composite resin (Z100®-3M, using a standard Teflon matrix. The specimens were stored in distilled water for 24 hours at a temperature of 37ºC. The tensile strength test was performed using a Mini Instrom testing machine. The mean values obtained for each group, in MPa, were: Group 1 - 7.37 (± 2.51; Group 2 - 11.25 (± 4.65; Group 3 - 9.80 (± 3.11; and Group 4 - 10.96 (± 3.37. The results were submitted to statistical analysis using the ANOVA test, and no statistical significant differences among the groups were found. It can be concluded that the different disinfectant substances used in this research do not adversely affect dentin adhesion.

  20. Bond strength of stainless steel orthodontic brackets bonded to prefabricated acrylic teeth.

    Science.gov (United States)

    Wan Abdul Razak, Wan Salbiah; Sherriff, Martyn; Bister, Dirk; Seehra, Jadbinder

    2017-06-01

    The purpose of this in-vitro study was to evaluate the force to debond stainless steel orthodontic brackets bonded to acrylic teeth using different combinations of adhesive and surface treatments. One hundred prefabricated upper lateral incisor acrylic teeth were divided into 4 equal groups: Transbond XT® adhesive only (Group 1, control), Transbond XT® adhesive with sandblasting (Group 2), Transbond XT® adhesive with abrasion / + methyl methacrylate (MMA) (Group 3) and Triad® Gel only (Group 4). The force in Newtons (N) to debond the brackets was measured. One-way analysis of variance (ANOVA) and pairwise multi-comparison of means (Šidak's adjustment) were undertaken. The highest force to debond was recorded for Group 2 (275.7 N; SD 89.0) followed by Group 3 (241.9 N; SD 76.0), Group 1 (142.7 N; SD 36.7) and Group 4 (67.9 N; SD 21.1). Significant differences in bond strength measurements between the experimental groups were detected. Mean force values for the groups revealed no significant differences between Group 2 and Group 3 (p>0.05). Both sandblasting and surface abrasion/+ application of methyl methacrylate (MMA) in combination with Transbond XT® adhesive are recommended for bonding stainless orthodontic brackets to acrylic teeth.

  1. The influence of main bar corrosion on bond strength in selfcompacting concrete

    Science.gov (United States)

    Ayop, S. S.; Emhemed, A. N. K.; Jamaluddin, N.; Sadikin, A.

    2017-11-01

    The experimental study was conducted to determine the influence of main bar corrosion on bond strength in self-compacting concrete (SCC). A total 16 tension pullout tests specimens reinforced with 10 mm and 14 mm diameter bar were used for the bond strength test. The properties of SCC were determined from the slump flow, T50cm, V-funnel and L box test. Reinforcing bars in the concrete were submitted to impressed current to accelerate the corrosion of the bar. It was found that the relationship between bond strength and concrete strength in un-corroded specimens differed from that of corroded specimens set in high-strength concrete because of brittleness in the corroded specimens, which caused a sudden loss of bond strength. The results revealed that specimens of un-corroded and corroded showed a higher percentage of bond strength degradation during the pullout tests.

  2. Shear bond strength of one-step self-etch adhesives: pH influence

    Science.gov (United States)

    Poggio, Claudio; Beltrami, Riccardo; Scribante, Andrea; Colombo, Marco; Chiesa, Marco

    2015-01-01

    Background: The aim of this study was to compare the shear bond strength of four one-step self-etch adhesives with different pH values to enamel and dentin. Materials and Methods: In this in vitro study, 200 bovine permanent mandibular incisors were used. Four one-step self-etch adhesives with different pH values were tested both on enamel and on dentin: Adper™ Easy Bond Self-Etch Adhesive (pH = 0.8-1), Futurabond NR (pH=2), G-aenial Bond (pH = 1.5), Clearfil S3 Bond (pH = 2.7). After adhesive systems application, a nanohybrid composite resin was inserted into the bonded surface. The specimens were placed in a universal testing machine. The shear bond strength was performed at a cross-head speed of 1 mm/min until the sample rupture. The shear bond strength values (MPa) of the different groups were compared with analysis of variance after that Kolmogorov and Smirnov tests were applied to assess normality of distributions. P enamel shear bond strength, the highest shear bond strength values were reported with Futurabond NR (P adhesive systems showed lower shear bond strength values with significant differences between them (P 0.05). Conclusion: The pH values of adhesive systems did not influence significantly their shear bond strength to enamel or dentin. PMID:26005459

  3. Strength of bond with Comspan Opaque to three silicoated alloys and titanium.

    Science.gov (United States)

    Hansson, O

    1990-06-01

    In Sweden high-gold alloys or cobalt-chromium alloys are used for resin-bonded prostheses. The bond strength between a resin cement and different sandblasted or silicoated metals were measured before and after thermocycling; in connection with this some rapid thermocycling methods were studied. The effect of different storage times and different protection coatings on bond strength were tested. Finally, the influence of rubbing and contamination with saliva on bond strength were investigated. Silicoating increased the bond strength significantly. The highest bond strengths were these of silicoated Wirobond and titanium, unsusceptible to thermal stress; the bond strengths of the sandblasted metals were the weakest, and sensitive to thermocycling as well. The influence on bond strength for silicoated gold alloys, protected with an unpolymerized composite resin coating, stored in sealed plastic bags up to 7 days, was negligible. Rubbing and contamination with saliva did not influence bond strength. Preferably, silicoated Wirobond and titanium should be used for resin-bonded prostheses, but gold alloys may still be adequate for clinical use. The experimental method described for storing, sealing, and cleaning the silicoated metal surfaces in this article can be recommended for laboratory and clinical use.

  4. Effect of Two-minute Application of 35% Sodium Ascorbate on Composite Bond Strength following Bleaching.

    Science.gov (United States)

    Ismail, Eman H; Kilinc, Evren; Hardigan, Patrick C; Rothrock, James K; Thompson, Jeffrey Y; Garcia-Godoy, Cristina

    2017-10-01

    The aim of this study is to assess the effect of 35% sodium ascorbate on microtensile bond strength of dentin immediately after bleaching with 35% hydrogen peroxide. A total of 25 sound human 3 rd molars were collected. Teeth were randomly divided into five groups for different treatments: Group I [bleaching + immediate bonding (i.e., restoration)], group II (bleaching + delayed bonding), group III (bleaching + sodium ascorbate + immediate bonding), group IV (bleaching + sodium ascorbate + delayed bonding), and group V (bonding only). After bleaching, but before bonding, groups II and IV were stored for 1 week in deionized water at 37°C. All samples were bonded using OptiBoned FL (Kerr) and Filtek Supreme (3M/ESPE). Teeth were sectioned into 1 × 1 mm 2 bars, and microtensile bond strength was tested with a universal testing machine (Instron 8841) at a cross-head speed of 0.5 mm/minute. Microtensile bond strength differed significantly across the five groups, with a significant reduction in microtensile bond strength observed for samples in group I relative to samples in any of the other treatment groups (p bleaching on composite bonding strength to dentin. The negative effects of bleaching on composite bonding can be neutralized by the application of the reversing agent sodium ascorbate thus, increasing the efficiency of clinic chair time. This is clinically relevant for those patients requiring restorative treatment immediately after in-office bleaching.

  5. The Effect on Final Bond Strength of Bracket Manipulation Subsequent To Initial Positioning

    Science.gov (United States)

    Beebe, David A.

    The shear bond strength of light activated orthodontic adhesives varies according to the composition of the material, placement protocol, and time prior to light curing. Manipulating brackets after their initial placement on a tooth can disrupt the adhesive's polymerization and compromise final bond strength. No previous research has investigated how a specific degree of manipulation, and the amount of time elapsed prior to curing, under specific lighting conditions, affects the orthodontic adhesives shear bond strength. Victory SeriesRTM, MBT prescription, premolar (3M Unitek, Monrovia, CA) orthodontic brackets were bonded using three different adhesives to sixty (60) bicuspids and varying the time after bracket manipulation before curing. The shear bond strength was calculated for each specimen. The brackets were debonded and the same teeth were rebonded with new, identical brackets, using the same protocol and under the same conditions. The results showed a statistically significant difference between the shear bond strength of Transbond XT and Grengloo, with Transbond XT having the highest strength. There was also a statistically significance difference in bond strength between the group cured 30 seconds after manipulation and the groups manipulated at different intervals prior to curing, with the 30 second group having the highest bond strength. This study confirms that various orthodontic adhesives have different bond strengths depending on manipulation and varying times prior to curing each adhesive.

  6. Investigation of the shear bond strength to dentin of universal adhesives applied with two different techniques

    Directory of Open Access Journals (Sweden)

    Elif Yaşa

    2017-09-01

    Full Text Available Objective: The aim of this study was to evaluate the shear bond strength of universal adhesives applied with self-etch and etch&rinse techniques to dentin. Materials and Method: Fourty-eight sound extracted human third molars were used in this study. Occlusal enamel was removed in order to expose the dentinal surface, and the surface was flattened. Specimens were randomly divided into four groups and were sectioned vestibulo-lingually using a diamond disc. The universal adhesives: All Bond Universal (Group 1a and 1b, Gluma Bond Universal (Group 2a and 2b and Single Bond Universal (Group 3a and 3b were applied onto the tooth specimens either with self-etch technique (a or with etch&rinse technique (b according to the manufacturers’ instructions. Clearfil SE Bond (Group 4a; self-etch and Optibond FL (Group 4b; etch&rinse were used as control groups. Then the specimens were restored with a nanohybrid composite resin (Filtek Z550. After thermocycling, shear bond strength test was performed with a universal test machine at a crosshead speed of 0.5 mm/min. Fracture analysis was done under a stereomicroscope (×40 magnification. Data were analyzed using two-way ANOVA and post-hoc Tukey tests. Results: Statistical analysis showed significant differences in shear bond strength values between the universal adhesives (p<0.05. Significantly higher bond strength values were observed in self-etch groups (a in comparison to etch&rinse groups (b (p<0.05. Among all groups, Single Bond Universal showed the greatest shear bond strength values, whereas All Bond Universal showed the lowest shear bond strength values with both application techniques. Conclusion: Dentin bonding strengths of universal adhesives applied with different techniques may vary depending on the adhesive material. For the universal bonding agents tested in this study, the etch&rinse technique negatively affected the bond strength to dentin.

  7. [Effects of surface treatment and adhesive application on shear bond strength between zirconia and enamel].

    Science.gov (United States)

    Li, Yinghui; Wu, Buling; Sun, Fengyang

    2013-03-01

    To evaluate the effects of sandblasting and different orthodontic adhesives on shear bond strength between zirconia and enamel. Zirconia ceramic samples were designed and manufactured for 40 extracted human maxillary first premolars with CAD/CAM system. The samples were randomized into 4 groups for surface treatment with sandblasting and non-treated with adhesives of 3M Transbond XT or Jingjin dental enamel bonding resin. After 24 h of bonded fixation, the shear bond strengths were measured by universal mechanical testing machine and analyzed with factorial variance analysis. The shear bond strength was significantly higher in sandblasting group than in untreated group (Padhesives of Transbond XT and dental enamel bonding resin (P>0.05). The shear bond strength between zirconia and enamel is sufficient after sandblasting regardless of the application of either adhesive.

  8. Effect of nanotechnology in self-etch bonding systems on the shear bond strength of stainless steel orthodontic brackets

    OpenAIRE

    Hammad, Shaza M.; El-Wassefy, Noha; Maher, Ahmed; Fawakerji, Shafik M.

    2017-01-01

    ABSTRACT Objective: To evaluate the effect of silica dioxide (SiO2) nanofillers in different bonding systems on shear bond strength (SBS) and mode of failure of orthodontic brackets at two experimental times. Methods: Ninety-six intact premolars were divided into four groups: A) Conventional acid-etch and primer Transbond XT; B) Transbond Plus self-etch primer; and two self-etch bonding systems reinforced with silica dioxide nanofiller at different concentrations: C) Futurabond DC at 1%; D...

  9. Influence of application methods of one-step self-etching adhesives on microtensile bond strength

    Directory of Open Access Journals (Sweden)

    Chul-Kyu Choi,

    2011-05-01

    Full Text Available Objectives The purpose of this study was to evaluate the effect of various application methods of one-step self-etch adhesives to microtensile resin-dentin bond strength. Materials and Methods Thirty-six extracted human molars were used. The teeth were assigned randomly to twelve groups (n = 15, according to the three different adhesive systems (Clearfil Tri-S Bond, Adper Prompt L-Pop, G-Bond and application methods. The adhesive systems were applied on the dentin as follows: 1 The single coating, 2 The double coating, 3 Manual agitation, 4 Ultrasonic agitation. Following the adhesive application, light-cure composite resin was constructed. The restored teeth were stored in distilled water at room temperature for 24 hours, and prepared 15 specimens per groups. Then microtensile bond strength was measured and the failure mode was examined. Results Manual agitation and ultrasonic agitation of adhesive significantly increased the microtensile bond strength than single coating and double coating did. Double coating of adhesive significantly increased the microtensile bond strength than single coating did and there was no significant difference between the manual agitation and ultrasonic agitation group. There was significant difference in microtensile bonding strength among all adhesives and Clearfil Tri-S Bond showed the highest bond strength. Conclusions In one-step self-etching adhesives, there was significant difference according to application methods and type of adhesives. No matter of the material, the manual or ultrasonic agitation of the adhesive showed significantly higher microtensile bond strength.

  10. [Bond strengths of customized titanium brackets manufactured by selective laser melting].

    Science.gov (United States)

    Zou, Dao-xing; Wang, Ze-min; Guo, Hong-ming; Li, Song; Bai, Yu-xing

    2013-07-01

    To investigate the bond strengths of customized titanium bracket manufactured by selective laser melting. Eighty human premolars which had been extracted for orthodontic purpose were collected and divided randomly (by random table) into two groups (customized bracket group and 3M bracket group, 40 molars in each group). The 35% phosphoric acid was used for etching and the brackets were bonded with 3M Unitek bonding adhesive. All bonded specimens were placed in saline for 24 hours at room temperature and were tested on DWD3050 electronic testing machine to determine the shear bond strength and tensile bond strength. After debonding, the adhesive remnant indexes (ARI) were recorded. The shear bond strengths of customized brackets was 6.80 (6.20, 8.32) MPa, which was significantly lower than that of the 3M brackets [10.46 (9.72, 11.48) MPa] (Z = -3.463, P < 0.05). And the tensile bond strengths of customized brackets was (6.93 ± 1.21) MPa, which was significantly higher than that of the 3M brackets [(5.88 ± 1.23) MPa] (t = 2.81, P < 0.05). No significant difference was found in the ARI between two different kinds of the brackets. The shear bond strength and tensile bond strength of both kinds of brackets were enough for clinic application.

  11. Effect of Adhesive Type on the Shear Bond Strength of Metal Brackets to Two Ceramic Substrates

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Ahmad Akhoundi

    2014-04-01

    Full Text Available Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin.Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM.The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05. There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected.Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.

  12. Do the Microshear Test Variables Affect the Bond Strength Values?

    Directory of Open Access Journals (Sweden)

    Andrea M. Andrade

    2012-01-01

    Full Text Available Little is known about the effect of specimen preparation and testing protocols on the micro-shear bond strength (μSBS results. To evaluate whether variations in polyethylene rod use affect (μSBS. Human dentin disks were randomly distributed into six groups (: polyethylene tube (3 levels and adhesive system (2 levels. In Group 1, polyethylene tubes filled with polymerized composite were placed on adhesive covered surfaces. Tubes were removed 24 h after water storage, leaving the rods only. In Group 2, the same procedure was performed; however, tubes were kept in place during testing. In Group 3, composite rods without tubes were placed on adhesive covered dentin. In all groups, adhesives were photoactivated after positioning filled tubes/rods on adhesive covered surfaces. Specimens were tested under shear mode and the data subjected to a two-way ANOVA and Tukey’s tests. Groups 1 and 2 resulted in statistically similar mean μSBS (; however, a greater number of pretest failures were observed for Group 1. Higher μSBS values were detected for Group 3, irrespective of adhesive system used (. Removing the polyethylene tube before composite rod is placed on dentin affects μSBS values.

  13. Comparison of bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and a universal adhesive.

    Science.gov (United States)

    Lee, Ji-Yeon; Ahn, Jaechan; An, Sang In; Park, Jeong-Won

    2018-02-01

    The aim of this study is to compare the shear bond strengths of ceramic brackets bonded to zirconia surfaces using different zirconia primers and universal adhesive. Fifty zirconia blocks (15 × 15 × 10 mm, Zpex, Tosoh Corporation) were polished with 1,000 grit sand paper and air-abraded with 50 µm Al 2 O 3 for 10 seconds (40 psi). They were divided into 5 groups: control (CO), Metal/Zirconia primer (MZ, Ivoclar Vivadent), Z-PRIME Plus (ZP, Bisco), Zirconia Liner (ZL, Sun Medical), and Scotchbond Universal adhesive (SU, 3M ESPE). Transbond XT Primer (used for CO, MZ, ZP, and ZL) and Transbond XT Paste was used for bracket bonding (Gemini clear ceramic brackets, 3M Unitek). After 24 hours at 37°C storage, specimens underwent 2,000 thermocycles, and then, shear bond strengths were measured (1 mm/min). An adhesive remnant index (ARI) score was calculated. The data were analyzed using one-way analysis of variance and the Bonferroni test ( p = 0.05). Surface treatment with primers resulted in increased shear bond strength. The SU group showed the highest shear bond strength followed by the ZP, ZL, MZ, and CO groups, in that order. The median ARI scores were as follows: CO = 0, MZ = 0, ZP = 0, ZL = 0, and SU = 3 ( p < 0.05). Within this experiment, zirconia primer can increase the shear bond strength of bracket bonding. The highest shear bond strength is observed in SU group, even when no primer is used.

  14. GROUT-CONCRETE INTERFACE BOND PERFORMANCE: EFFECT OF INTERFACE MOISTURE ON THE TENSILE BOND STRENGTH AND GROUT MICROSTRUCTURE.

    Science.gov (United States)

    De la Varga, I; Muñoz, J F; Bentz, D P; Spragg, R P; Stutzman, P E; Graybeal, B A

    2018-05-01

    Bond between two cementitious materials is crucial in applications such as repairs, overlays, and connections of prefabricated bridge elements (PBEs), to name just a few. It is the latter that has special interest to the authors of this paper. After performing a dimensional stability study on grout-like materials commonly used as connections between PBEs, it was observed that the so-called 'non-shrink' cementitious grouts showed a considerable amount of early-age shrinkage. This might have negative effects on the integrity of the structure, due not only to the grout material's early degradation, but also to a possible loss of bond between the grout and the prefabricated concrete element. Many factors affect the bond strength between two cementitious materials (e.g., grout-concrete), the presence of moisture at the existing concrete substrate surface being one of them. In this regard, pre-moistening the concrete substrate surface prior to the application of the grout material is sometimes recommended for bond enhancement. This topic has been the focus of numerous research studies in the past; however, there is still controversy among practitioners on the real benefits that this practice might provide. This paper evaluates the tensile bond performance of two non-shrink cementitious grouts applied to the exposed aggregate surface of a concrete substrate, and how the supply of moisture at the grout-concrete interface affects the bond strength. "Pull-off" bond results show increased tensile bond strength when the concrete surface is pre-moistened. Reasons to explain the observed increased bond strength are given after a careful microstructural analysis of the grout-concrete interface. Interfaces where sufficient moisture is provided to the concrete substrate such that moisture movement from the grout is prevented show reduced porosity and increased hydration on the grout side of the interface, which is thought to directly contribute to the increased tensile bond

  15. 3rd Workshop on metal ceramic materials for functional applications

    Energy Technology Data Exchange (ETDEWEB)

    Korb, G [Oesterreichisches Forschungszentrum Seibersdorf, 2444 Seibersdorf (Austria)

    1998-12-31

    This workshop contains contributions about materials and processing, characterization and modeling of properties and applications of metallic ceramics and composite structures. It was held on behalf of the Taiwan-Austrian scientific collaboration in Vienna, June 4{sup th} - 6{sup th} 1997. (Suda)

  16. 3rd Workshop on metal ceramic materials for functional applications

    International Nuclear Information System (INIS)

    Korb, G.

    1997-01-01

    This workshop contains contributions about materials and processing, characterization and modeling of properties and applications of metallic ceramics and composite structures. It was held on behalf of the Taiwan-Austrian scientific collaboration in Vienna, June 4 th - 6 th 1997. (Suda)

  17. Shear bond strength of composite bonded with three adhesives to Er,Cr:YSGG laser-prepared enamel.

    Science.gov (United States)

    Türkmen, Cafer; Sazak-Oveçoğlu, Hesna; Günday, Mahir; Güngör, Gülşad; Durkan, Meral; Oksüz, Mustafa

    2010-06-01

    To assess in vitro the shear bond strength of a nanohybrid composite resin bonded with three adhesive systems to enamel surfaces prepared with acid and Er,Cr:YSGG laser etching. Sixty extracted caries- and restoration-free human maxillary central incisors were used. The teeth were sectioned 2 mm below the cementoenamel junction. The crowns were embedded in autopolymerizing acrylic resin with the labial surfaces facing up. The labial surfaces were prepared with 0.5-mm reduction to receive composite veneers. Thirty specimens were etched with Er,Cr:YSGG laser. This group was also divided into three subgroups, and the following three bonding systems were then applied on the laser groups and the other three unlased groups: (1) 37% phosphoric acid etch + Bond 1 primer/adhesive (Pentron); (2) Nano-bond self-etch primer (Pentron) + Nano-bond adhesive (Pentron); and (3) all-in-one adhesive-single dose (Futurabond NR, Voco). All of the groups were restored with a nanohybrid composite resin (Smile, Pentron). Shear bond strength was measured with a Zwick universal test device with a knife-edge loading head. The data were analyzed with two-factor ANOVA. There were no significant differences in shear bond strength between self-etch primer + adhesive and all-in-one adhesive systems for nonetched and laser-etched enamel groups (P > .05). However, bond strength values for the laser-etched + Bond 1 primer/adhesive group (48.00 +/- 13.86 MPa) were significantly higher than the 37% phosphoric acid + Bond 1 primer/adhesive group (38.95 +/- 20.07 MPa) (P enamel surface more effectively than 37% phosphoric acid for subsequent attachment of composite material.

  18. Post-bleaching application of an antioxidant on dentin bond strength of three dental adhesives

    Directory of Open Access Journals (Sweden)

    Maryam Khoroushi

    2012-01-01

    Conclusions: The findings suggest that bond strength of resin to bleached dentin may be affected with the adhesive system. Reduced SBS to bleached dentin can be amended by the use of SA as an antioxidizing agent. However, the amount of reversed bond strength subsequent to applying antioxidant might be related to the kind of dental adhesive.

  19. In-vitro orthodontic bond strength testing : A systematic review and meta-analysis

    NARCIS (Netherlands)

    Finnema, K.J.; Ozcan, M.; Post, W.J.; Ren, Y.J.; Dijkstra, P.U.

    INTRODUCTION: The aims of this study were to systematically review the available literature regarding in-vitro orthodontic shear bond strength testing and to analyze the influence of test conditions on bond strength. METHODS: Our data sources were Embase and Medline. Relevant studies were selected

  20. Investigation of the bond strength between the photo-sensitive polymer SU-8 and Au

    DEFF Research Database (Denmark)

    Nordstrom, Maria; Johansson, Alicia; Sanches-Noguerón, E.

    2004-01-01

    promotors between the SU-8 and Au (ii) the effect of the processing sequence, either keeping SU-8 as bottum layer or Au (iii) varying the UV exposure dosage of the SU-8. For comparison, also the bond strength between SU-8 and other materials was measured. We report on bond strength of 4.8 +/- 1.2 MPa...

  1. Effect of different surface treatments on bond strength, surface and microscopic structure of zirconia ceramic

    Directory of Open Access Journals (Sweden)

    Zeinab R. El-Shrkawy

    2016-06-01

    Conclusions: (1 Surface treatments of Y-TZP ceramic together with MDP primer and silane-coupling agent application improve the bond strength to resin cement. (2 Plasma-Silica coating and plasma-oxygen treatment, both are valuable methods that improve the bond strength of resin cement to Y-TZP ceramic. (3 Silica coating by plasma technology provides durable bond strength and can be a promising alternative pretreatment before silane application to enhance bonding with zirconia ceramic. (4 Tetragonal-monoclinic phase transformation had occurred in Y-TZP samples received both types of plasma treatment.

  2. The Relative Hydrogen Bonding Strength of Oxygen and Nitrogen Atoms as a Proton Acceptor

    International Nuclear Information System (INIS)

    Hyun, Jong Cheol; Lee, Ho Jin; Kim, Nak Kyoon; Choi, Young Sang; Park, Jeung Hee; Yoon, Chang Ju

    1999-01-01

    The thermodynamic parameters for the formation of the hydrogen bonding were widely used to understand the protein- ligand interaction. We have been interested in the hydrogen bonding strength of various proton acceptors toward the amide in a nonpolar solvent, This work is in the line of our interest. In drug design, the functional group is often replaced in order to enhance or reduce the binding affinity, which is usually determined by hydrogen bonding strength. Therefore, to understand this biochemical process the knowledge of relative hydrogen bonding strength is of importance.

  3. Comparative in vitro study of the shear bond strength of brackets bonded with restorative and orthodontic resins

    Directory of Open Access Journals (Sweden)

    Hassan Isber

    2011-02-01

    Full Text Available The aim of this study was to evaluate the shear bond strength of brackets bonded with different restorative systems and compare it with that afforded by an established orthodontic bonding system. Seventy human bicuspids were used, divided into five different groups with 14 teeth each. Whereas a specific orthodontic bonding resin (TransbondTM XT was used in the control group, the restorative systems Charisma, Tetric Ceram, TPH Spectrum and Z100 were used in the other four groups. Seven days after bonding the brackets to the samples, shear forces were applied under pressure in a universal testing machine. The data collected was evaluated using the ANOVA test and, when a difference was identified, the Tukey test was applied. A 5% level of significance was adopted. The mean results of the shear bond strength tests were as follows: Group 1 (Charisma, 14.98 MPa; Group 2 (Tetric Ceram, 15.16 MPa; Group 3 (TPH, 17.70 MPa; Group 4 (Z100, 13.91 MPa; and Group 5 or control group (TransbondTM XT, 17.15 MPa. No statistically significant difference was found among the groups. It was concluded that all tested resins have sufficient bond strength to be recommended for bonding orthodontic brackets.

  4. Shear bond strength of resin composite bonded with two adhesives: Influence of Er: YAG laser irradiation distance

    Science.gov (United States)

    Shirani, Farzaneh; Birang, Reza; Malekipour, Mohammad Reza; Hourmehr, Zahra; Kazemi, Shantia

    2014-01-01

    Background: Dental surfaces prepared with different Er:YAG laser distance may have different characteristics compared with those prepared with conventional instruments. The aim of this study was to investigate the effect of Er:YAG laser irradiation distance from enamel and dentin surfaces on the shear bond strength of composite with self-etch and etch and rinse bonding systems compared with conventional preparation method. Materials and Methods: Two hundred caries-free human third molars were randomly divided into twenty groups (n = 10). Ten groups were designated for enamel surface (E1-E10) and ten for dentin surface (D1-D10). Er: YAG laser (2940 nm) was used on the E1-E8 (240 mJ, 25 Hz) and D1-D8 (140 mJ, 30 Hz) groups at four different distances of 0.5 (standard), 2, 4 and 11 mm. Control groups (E9, E10, D9 and D10) were ground with medium grit diamond bur. The enamel and dentin specimens were divided into two subgroups that were bonded with either Single Bond or Clearfil SE Bond. Resin composite (Z100) was dispensed on prepared dentin and enamel. The shear bond strengths were tested using a universal testing machine. Data were analyzed by SPSS12 statistical software using three way analysis of variance, Tukey and independent t-test. P enamel and dentin substrates (P enamel surfaces (in both bonding agent subgroups) and on dentin surfaces (in the Single Bond subgroup). Conclusion: Laser irradiation decreases shear bond strength. Irradiation distance affects shear bond strength and increasing the distance would decrease the negative effects of laser irradiation. PMID:25540665

  5. Effect of a New Salivary Contaminant Removal Method on Bond Strength

    Science.gov (United States)

    2014-08-31

    was to evaluate the effect of various salivary- contaminant removal methods on the shear bond strength of resin cement to hydrofluoric-acid (HF) etched...mold (Ultradent) to a height of 3mm and light cured . Specimens were stored for 24 hours in 37°C distilled water and then tested in shear in a... contamination which may compromise the bond strength of the resin cement to the ceramic (Aboush, 1998; van Schalkwyk et al., 2003). Saliva affects bond

  6. The impact of chlorhexidine mouth rinse on the bond strength of polycarbonate orthodontic brackets.

    Science.gov (United States)

    Hussein, Farouk Ahmed; Hashem, Mohammed Ibrahim; Chalisserry, Elna P; Anil, Sukumaran

    2014-11-01

    The purpose of the current in-vivo study was to assess the effect of using 0.12% chlorhexidine (CHX) mouth rinse, before bonding, on shear bond strength of polycarbonate brackets bonded with composite adhesive. Eighteen orthodontic patients with a mean age 21.41 ± 1.2 years, who were scheduled to have 2 or more first premolars extracted, were included in this study. Patients were referred for an oral prophylaxis program which included, in part, the use of a mouth rinse. Patients were divided into 2 groups, a test group of 9 patients who used 0.12% CHX gluconate mouth rinse twice daily and a control group of 9 patients who used a mouth rinse without CHX, but with same color. After 1 week, polycarbonate brackets were bonded to first premolars with Transbond XT composite adhesive. Premolars were extracted after 28 days and tested for shear bond strength on a universal testing machine. Student's t-test was used to compare shear bond strengths of both groups. No statistically significant difference was found in bond strengths' values between both groups. The test group (with CHX) has mean shear bond strength of 14.21 ± 2.42 MPa whereas the control group (without CHX) revealed a mean strength of 14.52 ± 2.31 MPa. The use of 0.12% CHX mouth rinse, for one week before bonding, did not affect the shear bond strength of polycarbonate brackets bonded with Transbond composite. Furthermore, these brackets showed clinically acceptable bond strength.

  7. Effect of Storage Time on Bond Strength and Nanoleakage Expression of Universal Adhesives Bonded to Dentin and Etched Enamel.

    Science.gov (United States)

    Makishi, P; André, C B; Ayres, Apa; Martins, A L; Giannini, M

    2016-01-01

    To investigate bond strength and nanoleakage expression of universal adhesives (UA) bonded to dentin and etched enamel. Extracted human third molars were sectioned and ground to obtain flat surfaces of dentin (n = 36) and enamel (n = 48). Dentin and etched enamel surfaces were bonded with one of two UAs, All-Bond Universal (ABU) or Scotchbond Universal (SBU); or a two-step self-etching adhesive, Clearfil SE Bond (CSEB). A hydrophobic bonding resin, Adper Scotchbond Multi-Purpose Bond (ASMP Bond) was applied only on etched enamel. Following each bonding procedure, resin composite blocks were built up incrementally. The specimens were sectioned and subjected to microtensile bond strength (MTBS) testing after 24 hours or one year water storage, or immersed into ammoniacal silver nitrate solution after aging with 10,000 thermocycles and observed using scanning electron microscopy. The percentage distribution of silver particles at the adhesive/tooth interface was calculated using digital image-analysis software. The MTBS (CSEB = SBU > ABU, for dentin; and CSEB > ABU = SBU = ASMP Bond, for etched enamel) differed significantly between the adhesives after 24 hours. After one year, MTBS values were reduced significantly within the same adhesive for both substrates (analysis of variance, Bonferroni post hoc, padhesives for etched enamel. Silver particles could be detected within the adhesive/dentin interface of all specimens tested. Kruskal-Wallis mean ranks for nanoleakage in ABU, SBU, and CSEB were 16.9, 18.5 and 11, respectively (p>0.05). In the short term, MTBS values were material and dental-substrate dependent. After aging, a decrease in bonding effectiveness was observed in all materials, with nanoleakage at the adhesive/dentin interface. The bonding of the UAs was equal or inferior to that of the conventional restorative systems when applied to either substrate and after either storage period.

  8. Effect of a whitening agent application on enamel bond strength of self-etching primer systems.

    Science.gov (United States)

    Miyazaki, Masashi; Sato, Hikaru; Sato, Tomomi; Moore, B Keith; Platt, Jeffrey A

    2004-06-01

    Though reduction in bond strength after tooth whitening has been reported, little is known about it's effect on enamel bond strength of two-step bonding systems that exclude phosphoric acid etching prior to bonding agent application. The purpose of this study was to determine the effect of whitening procedure using an in-office whitening agent on enamel bond strength of self-etching primer systems. Three self-etching primer systems, Imperva Fluoro Bond, Mac Bond II, Clearfil SE Bond, and a one-bottle adhesive system Single Bond as a control material, were used. Bovine mandibular incisors were mounted in self-curing resin and the facial enamel or dentin surfaces were ground wet on 600-grit SiC paper. An in-office whitening agent, Hi-Lite was applied on the tooth surface according to the manufacturer's instruction. Bonding procedures were done soon after rinsing off the whitening agent or after 24 hours storage in distilled water. Specimens without whitening procedure were prepared as controls. Fifteen specimens per test group were stored in 37 degrees C distilled water for 24 hours, then shear tested at a crosshead speed of 1.0 mm/minute. One-way ANOVA followed by Duncan multiple range test were used for statistical analysis of the results. For the specimens made soon after rinsing off the whitening agent, a significant decrease in enamel bond strength was observed for all the bonding systems used. For the specimens made after 24 hours storage in water, a small decrease in enamel bond strength was observed and no significant differences were found compared to those of controls (without whitening). From the results of this study, enamel bond strengths of the self-etching primer systems might be affected to a lesser degree after rinsing with water followed by 24 hours storage in water.

  9. Enamel Wetness Effects on Microshear Bond Strength of Different Bonding Agents (Adhesive Systems): An in vitro Comparative Evaluation Study.

    Science.gov (United States)

    Kulkarni, Girish; Mishra, Vinay K

    2016-05-01

    The purpose of this study was to compare the effect of enamel wetness on microshear bond strength using different adhesive systems. To evaluate microshear bond strength of three bonding agents on dry enamel; to evaluate microshear bond strength of three bonding agents on wet enamel; and to compare microshear bond strength of three different bonding agents on dry and wet enamel. Sixty extracted noncarious human premolars were selected for this study. Flat enamel surfaces of approximately 3 mm were obtained by grinding the buccal surfaces of premolars with water-cooled diamond disks. This study evaluated one etch-and-rinse adhesive system (Single Bond 2) and two self-etching adhesive systems (Clearfil SE Bond and Xeno-V). The specimens were divided into two groups (n = 30). Group I (dry) was air-dried for 30 seconds and in group II (wet) surfaces were blotted with absorbent paper to remove excess water. These groups were further divided into six subgroups (n = 10) according to the adhesives used. The resin composite, Filtek Z 250, was bonded to flat enamel surfaces that had been treated with one of the adhesives, following the manufacturer's instructions. After being stored in water at 37°C for 24 hours, bonded specimens were stressed in universal testing machine (Fig. 3) at a crosshead speed of 1 mm/min. The data were evaluated with one-way and two-way analysis of variance (ANOVA), t-test, and Tukey's Multiple Post hoc tests (a = 0.05). The two-way ANOVA and Tukey's Multiple Post hoc tests showed significant differences among adhesive systems, but wetness did not influence microshear bond strength (p = 0.1762). The one-way ANOVA and t-test showed that the all-in-one adhesive (Xeno-V) was the only material influenced by the presence of water on the enamel surface. Xeno-V showed significantly higher microshear bond strength when the enamel was kept wet. Single Bond 2 adhesive showed significantly higher microshear bond strength as compared with Xeno-V adhesive but no

  10. Shear bond strength of precoated orthodontic brackets: an in vivo study

    OpenAIRE

    Hassan, Ali H

    2010-01-01

    Ali H HassanDepartment of Preventive Dental Sciences, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi ArabiaObjective: To evaluate the shear bond strength of precoated orthodontic brackets bonded with self-etching primer relative to that of noncoated conventionally-bonded brackets at two different time intervals.Methods: Twenty-one subjects were selected for randomized split-mouth bonding of two types of brackets to the maxillary arch. Half of the teeth had precoated brackets b...

  11. Effect of Adhesive Type on the Shear Bond Strength of Metal Brackets to Two Ceramic Substrates

    OpenAIRE

    Mohammad Sadegh Ahmad Akhoundi; Farzaneh Aghajani; Javad Chalipa; Amir Hooman Sadrhaghighi

    2014-01-01

    Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin.Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting,...

  12. Comparison of hydroxyapatite and dental enamel for testing shear bond strengths.

    Science.gov (United States)

    Imthiaz, Nishat; Georgiou, George; Moles, David R; Jones, Steven P

    2008-05-01

    To investigate the feasibility of using artificial hydroxyapatite as a future biomimetic laboratory substitute for human enamel in orthodontic bond strength testing by comparing the shear bond strengths and nature of failure of brackets bonded to samples of hydroxyapatite and enamel. One hundred and fifty hydroxyapatite discs were prepared by compression at 20 tons and fired in a furnace at 1300 degrees C. One hundred and five enamel samples were prepared from the buccal and palatal/lingual surfaces of healthy premolars extracted for orthodontic purposes. Orthodontic brackets were bonded to each sample and these were subjected to shear bond strength testing using a custom-made jig mounted in an Instron Universal Testing Machine. The force value at bond failure was obtained, together with the nature of failure which was assessed using the Adhesive Remnant Index. The mean shear bond strength for the enamel samples was 16.62 MPa (95 per cent CI: 15.26, 17.98) and for the hydroxyapatite samples 20.83 MPa (95 per cent CI: 19.68, 21.98). The difference between the two samples was statistically significant (p enamel samples scored 2 or 3, while 49 per cent of the hydroxyapatite samples scored 0 or 1. Hydroxyapatite was an effective biomimetic substrate for bond strength testing with a mean shear bond strength value (20.83 MPa) at the upper end of the normal range attributed to enamel (15-20 MPa). Although the difference between the shear bond strengths for hydroxyapatite and enamel was statistically significant, hydroxyapatite could be used as an alternative to enamel for comparative laboratory studies until a closer alternative is found. This would eliminate the need for extracted teeth to be collected. However, it should be used with caution for quantitative studies where true bond strengths are to be investigated.

  13. Water and saliva contamination effect on shear bond strength of brackets bonded with a moisture-tolerant light cure system.

    Science.gov (United States)

    Vicente, Ascensión; Mena, Ana; Ortiz, Antonio José; Bravo, Luis Alberto

    2009-01-01

    To evaluate the effects of water and saliva contamination on shear bond strength of brackets bonded with a moisture-tolerant light cure system. Brackets were bonded to 240 bovine lower incisors divided into 12 groups. Four bonding procedures were evaluated, including (1) TSEP/Transbond XT, (2) TMIP/ Transbond XT, (3) TSEP/Transbond PLUS, and (4) TMIP/Transbond PLUS, each under three different bonding conditions: without contamination, with water contamination, and with saliva contamination. Shear bond strength was measured with a universal testing machine. The adhesive remnant on the teeth was quantified with the use of image analyzing equipment. Without contamination, bond strengths for the four procedures were similar (P > .05). TSEP/Tranbond PLUS and TMIP/Transbond PLUS left significantly less adhesive on the teeth after debonding than TSEP/Transbond XT and TMIP/Transbond XT (P .017), although for TMIP/ Transbond XT, both variables showed significant reductions after contamination (P < .017). TSEP/Transbond PLUS, TMIP/Transbond PLUS, and TSEP/Transbond XT showed greater tolerance to wet conditions than was shown by TMIP/Transbond XT.

  14. Comparison of shear bond strength of orthodontic brackets bonded using two different hydrophilic primers: An in vitro study

    Directory of Open Access Journals (Sweden)

    M Kumaraswamy Anand

    2014-01-01

    Full Text Available Context: Salivary control and maintenance of a dry operating field is a prime requisite of orthodontic bonding. Moisture insensitive primer (MIP with a clinical significant bond strength values have a better edge over the conventional hydrophobic bonding systems. Aim: The aim of this study is to investigate the effectiveness of two hydrophilic primers with respect to conventional hydrophobic primer by comparing their shear bond strength (SBS and adhesive-failure locations after contamination with saliva and saliva substitute. Materials and Methods: A total of 150 extracted human premolars were randomly divided into five group s ; Group A (Transbond MIP/saliva substitute, Group B (Opal Primo/saliva substitute, Group C (Transbond MIP/natural saliva, Group D (Opal Primo/natural saliva, control group - Group E (Transbond XT/dry, adhesive-Transbond XT used for all five groups and bonded using stainless steel brackets. Shear forces were applied to the samples with a universal testing machine. SBSs was measured in megapascals. The mode of bond failure was determined using the adhesive remnant index (ARI. Results: The mean SBS produced by Transbond MIP was higher than Opal Primo, which was statistically significant according to one-way analysis of variance. Both the tested groups showed lesser bond strength values than Transbond XT (the control. ARI scores revealed that there was no statistically significant difference in the site of bond failure between study groups. ARI scores were found to be lower for study groups suggesting adhesive failure, compared to higher ARI scores for the control group suggesting cohesive failure. Conclusion: Transbond XT adhesive with Transbond MIP or Opal Primo have clinically acceptable bond strength in wet fields. Opal Primo is a viable option to use as a hydrophilic primer clinically.

  15. Bond strength of the porcelain repair system to all-ceramic copings and porcelain.

    Science.gov (United States)

    Lee, Sang J; Cheong, Chan Wook; Wright, Robert F; Chang, Brian M

    2014-02-01

    The purpose of this study was to investigate the shear bond strength of the porcelain repair system on alumina and zirconia core ceramics, comparing this strength with that of veneering porcelain. Veneering ceramic (n = 12), alumina core (n = 24), and zirconia core (n = 24) blocks measuring 10 × 5 × 5 mm(3) were fabricated. Veneering ceramic blocks were used as the control. Alumina and zirconia core blocks were divided into 2 groups (n = 12 each), and a slot (2 × 2 × 4 mm(3)) filled with veneering ceramics was prepared into one of the alumina and zirconia core groups (n = 12). Followed by surface treatments of micro-abrasion with 30 μm alumina particles, etching with 35% phosphoric acid and silane primer and bond, composite resin blocks (2 × 2 × 2 mm(3)) were built up and light polymerized onto the treated surfaces by 3 configurations: (a) composite blocks bonded onto veneering ceramic surface alone, (b) composite blocks bonded onto alumina core or zirconia core surfaces, (c) a 50% surface area of the composite blocks bonded to veneering ceramics and the other 50% surface area of the composite blocks to alumina core or zirconia core surfaces. The shear bond strength of the composite to each specimen was tested by a universal testing machine at a 0.5 mm/min crosshead speed. The shear bond strength was analyzed by unpaired t-tests for within the configuration groups and ANOVA for among the different configuration groups. When the mean shear bond strength was compared within groups of the same configuration, there were no statistically significant differences. Comparison of the shear bond strength among groups of different configurations revealed statistically significant differences. The mean shear bond strength of composite onto 100% veneering ceramic surface and composite onto 50% veneering 50% all-ceramic cores was statistically higher than that of composite onto 100% all-ceramic cores; however, the differences of the shear bond strength of composite bonded

  16. Microtensile bond strength of contemporary adhesives to primary enamel and dentin.

    Science.gov (United States)

    Marquezan, Marcela; da Silveira, Bruno Lopes; Burnett, Luiz Henrique; Rodrigues, Célia Regina Martins Delgado; Kramer, Paulo Floriani

    2008-01-01

    The purpose of this study was to assess bond strength of three self-etching and two total-etch adhesive systems bonded to primary tooth enamel and dentin. Forty extracted primary human molars were selected and abraded in order to create flat buccal enamel and occlusal dentin surfaces. Teeth were assigned to one of the adhesive systems: Adper Scotch Bond Multi Purpose, Adper Single Bond 2, Adper Prompt L-Pop, Clearfil SE Bond and AdheSE. Immediately to adhesive application, a composite resin (Filtek Z250) block was built up. After 3 months of water storage, each sample was sequentially sectioned in order to obtain sticks with a square cross-sectional area of about 0.72 mm2. The specimens were fixed lengthways to a microtensile device and tested using a universal testing machine with a 50-N load cell at a crosshead speed of 0.5 mm/min. Microtensile bond strength values were recorded in MPa and compared by Analysis of Variance and the post hoc Tukey test (a = 0.05). In enamel, Clearfil SE Bond presented the highest values, followed by Adper Single Bond 2, AdheSE and Adper Scotch Bond Multi Purpose, without significant difference. The highest values in dentin were obtained with Adper Scotch Bond Multi Purpose and all other adhesives did not present significant different values from that, except Adper Prompt L-Pop that achieved the lowest bond strength in both substrates. Adper Scotch Bond Multi Purpose and Adper Single Bond 2 presented significantly lower values in enamel than in dentin although all other adhesives presented similar results in both substrates. contemporary adhesive systems present similar behaviors when bonded to primary teeth, with the exception of the one-step self-etching system; and self-etching systems can achieve bond strength values as good in enamel as in dentin of primary teeth.

  17. Papain-based gel for biochemical caries removal: influence on microtensile bond strength to dentin

    Directory of Open Access Journals (Sweden)

    Evandro Piva

    2008-12-01

    Full Text Available This study investigated the influence of a papain-based gel (Papacárie for chemo-mechanical caries removal on bond strength to dentin. Human molars were assigned to the following groups: Group 1: sound teeth were flattened to expose dentin; Group 2: after flattening of surfaces, the papain-based gel was applied on the sound dentin; Group 3: overlying enamel from carious teeth was removed and mechanical excavation of dentin was conducted; Group 4: chemo-mechanical excavation of carious dentin was conducted using the papain-based gel. The Prime&Bond NT or Clearfil SE Bond adhesive systems were used for restorative procedures. A microtensile bond strength test was performed, and the modes of failure were determined under SEM. The data were submitted to two-way ANOVA and Tukey's test (p < 0.05. No significant differences were observed between the sound dentin groups. For both excavation methods, Clearfil presented a significantly higher bond strength than Prime&Bond NT. Also, for Clearfil, the mechanically excavated samples disclosed a significantly higher bond strength than the chemo-mechanically ones. For Prime&Bond NT, no significant differences were detected between the excavation methods. Predominance of mixed failures for the sound substrate and of adhesive failures for the carious dentin one was detected. The bond strength to carious dentin of the self-etching system was negatively affected by chemo-mechanical excavation using the papain-based gel.

  18. SHORT- AND LONG-TERM BOND STRENGTHS OF A GOLD STANDARD

    Directory of Open Access Journals (Sweden)

    Safa TUNCER

    2015-04-01

    Full Text Available Purpose: The aim of this study was to investigate the micro tensile bond strength of a self-etch adhesive system following 1 year storage in water. Materials and Methods: 10 sound human molar teeth were used for micro tensile bond strength test. Twostep self-etch dentin adhesive (Clearfil SE Bond® was applied to the flat dentin surfaces according to the manufacturer’s instructions. Composite blocks (Z- 250; 3M ESPE of 5 mm in height have been prepared by using layering technique. Teeth were stored in water for 24 hours at 37°C and longitudinally sectioned to obtain dentin sticks of 1 mm2.Randomly selected samples from half of the teeth were immediately subjected to micro tensile test and. Remaining specimens were tested after 1 year storage in water. Bond strengths were calculated in megapascal (MPa. Results: Means and standard deviations of the Clearfil SE Bond® micro tensile bond strength values were, respectively, 37.31 ± 13.77 MPa and 24.78 ± 2.99 MPa after 24 h and 1 year of storage in water. The difference was statistically significant (p=0.031. Conclusion: Long-term storage in water decreased the micro tensile bond strength values of the twostep self-etch adhesive which has been accepted as the gold standard in bond strength tests.

  19. [Bonding strength of resin and tooth enamel after teeth bleaching with cold plasma].

    Science.gov (United States)

    Zhu, Meng-meng; Wang, Guo-min; Sun, Ke; Li, Ying-long; Pan, Jie

    2016-02-18

    To investigate the immediate bond strength and surface structure of resin and the tooth enamel which treated by cold plasma. In the study, 40 bovine incisors were divided into two equal parts. In this sense, all enamel adhesive samples were prepared and then randomly divided into 4 groups (n =20). group 1: acid + single bond 2+resin composite (control group); group 2:beyond bleaching+ acid+single bond 2+resin composite; group 3: treated by cold plasma for 5 minutes+ acid+single bond 2+resin composite; group 4: treated by cold plasma for 5 minutes+single bond 2+resin composite. Single bond 2 bonding system and Filtek Z250 resin were used in this experiment. The shear bond strength was tested by universal testing machine. The surface of the enamel in different processes was observed by scanning electron microscope (SEM). Statistical analyses by the single factor analysis of variance and multiple pairwise comparisons were performed with SPSS 17.0 . The shear bond strength of group 4 (8.60 MPa) was significantly lower than that of the other three groups (Penamel treated by cold plasma had slight molten form, which was different from etched enamel surface.The fractured surface of group 3 was mix fracture, which was similar to the control group (group 1). Compared with the conventional clinic bleaching, immediate bond strength of resin-enamel that treated by cold plasma has not been affected.

  20. Push-out bond strength of bioceramic materials in a synthetic tissue fluid.

    Directory of Open Access Journals (Sweden)

    Noushin Shokouhinejad

    2013-12-01

    Full Text Available This study compared the push-out bond strength of EndoSequence Root Repair Material (ERRM and Bioaggregate (BA, new bioceramic materials, to that of mineral trioxide aggregate (MTA after incubation in phosphate-buffered saline (PBS, a synthetic tissue fluid, for either 1 week or 2 months.One-hundred and twenty root sections were filled with ProRoot MTA, BA, or ERRM. Each tested material was then randomly divided into two subgroups (n = 20: root sections were immersed in PBS for 1 week or 2 months. The bond strengths were measured using a universal testing machine. After that, the failure modes were examined with stereomicroscopy and scanning electron microscopy (SEM. The push-out data and failure mode categories were analyzed by two-way ANOVA and chi-square tests, respectively.The bond strength of ERRM was significantly higher than that of BA and MTA at both incubation periods. No significant difference was found between the bond strength of MTA and BA at either 1 week or 2 months. Increasing the incubation time to 2 months resulted in a significant increase in bond strength of all the materials. The failure mode was mainly mixed for MTA and BA, but cohesive for ERRM at both incubation periods.ERRM had significantly higher bond strength to root canal walls compared to MTA and BA. Increasing the incubation time significantly improved the bond strength and bioactive reaction products of all materials.

  1. Shear bond strength between an indirect composite layering material and feldspathic porcelain-coated zirconia ceramics.

    Science.gov (United States)

    Fushiki, Ryosuke; Komine, Futoshi; Blatz, Markus B; Koizuka, Mai; Taguchi, Kohei; Matsumura, Hideo

    2012-10-01

    This study aims to evaluate the effect of both feldspathic porcelain coating of zirconia frameworks and priming agents on shear bond strength between an indirect composite material and zirconia frameworks. A total of 462 airborne-particle-abraded zirconia disks were divided into three groups: untreated disks (ZR-AB), airborne-particle-abraded zirconia disks coated with feldspathic porcelain, (ZR-PO-AB), and hydrofluoric acid-etched zirconia disks coated with feldspathic porcelain (ZR-PO-HF). Indirect composite (Estenia C&B) was bonded to zirconia specimens with no (CON) or one of four priming agents--Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + activator), Estenia Opaque primer, or Porcelain Liner M Liquid B (PLB)--with or without an opaque material (Estenia C&B Opaque). All specimens were tested for shear bond strength before and after 20,000 thermocycles. The Steel-Dwass test and Mann-Whitney U test were used to compare shear bond strength. In ZR-AB specimens, the initial bond strength of the CPB and CPB + Activator groups was significantly higher as compared with the other three groups (P material, bond strength was significantly lower in ZR-AB specimens than in ZR-PO-AB and ZR-PO-HF specimens (P composite to zirconia independent of surface treatment. The use of a silane coupling agent and opaque material yields durable bond strength between the indirect composite and feldspathic-porcelain-coated zirconia. The results of the present study suggest that feldspathic porcelain coating of zirconia frameworks is an effective method to obtain clinically acceptable bond strengths of a layering indirect composite material to a zirconia framework.

  2. Tensile Bond Strength of Self Adhesive Resin Cement After Various Surface Treatment of Enamel.

    Science.gov (United States)

    Sekhri, Sahil; Mittal, Sanjeev; Garg, Sandeep

    2016-01-01

    In self adhesive resin cements adhesion is achieved to dental surface without surface pre-treatment, and requires only single step application. This makes the luting procedure less technique-sensitive and decreases postoperative sensitivity. The purpose of this study was to evaluate bond strength of self adhesive resin after surface treatment of enamel for bonding base metal alloy. On the labial surface of 64 central incisor rectangular base metal block of dimension 6 mm length, 5mm width and 1 mm height was cemented with RelyX U200 and Maxcem Elite self adhesive cements with and without surface treatment of enamel. Surface treatment of enamel was application of etchant, one step bonding agent and both. Tensile bond strength of specimen was measured with universal testing machine at a cross head speed of 1mm/min. Least tensile bond strength (MPa) was in control group i.e. 1.33 (0.32) & 1.59 (0.299), Highest bond strength observed when enamel treated with both etchant and bonding agent i.e. 2.72 (0.43) & 2.97 (0.19) for Relyx U200 and Elite cement. When alone etchant and bonding agent were applied alone bond strength is 2.19 (0.18) & 2.24 (0.47) for Relyx U200, and 2.38 (0.27) 2.49 (0.16) for Max-cem elite. Mean bond strength was higher in case of Max-cem Elite as compared to RelyX U200 resin cement, although differences were non-significant (p > 0.05). Surface treatment of enamel increases the bond strength of self adhesive resin cement.

  3. Tensile Bond Strength of Self Adhesive Resin Cement After Various Surface Treatment of Enamel

    Science.gov (United States)

    Sekhri, Sahil; Garg, Sandeep

    2016-01-01

    Introduction In self adhesive resin cements adhesion is achieved to dental surface without surface pre-treatment, and requires only single step application. This makes the luting procedure less technique-sensitive and decreases postoperative sensitivity. Aim The purpose of this study was to evaluate bond strength of self adhesive resin after surface treatment of enamel for bonding base metal alloy. Materials and Methods On the labial surface of 64 central incisor rectangular base metal block of dimension 6 mm length, 5mm width and 1 mm height was cemented with RelyX U200 and Maxcem Elite self adhesive cements with and without surface treatment of enamel. Surface treatment of enamel was application of etchant, one step bonding agent and both. Tensile bond strength of specimen was measured with universal testing machine at a cross head speed of 1mm/min. Results Least tensile bond strength (MPa) was in control group i.e. 1.33 (0.32) & 1.59 (0.299), Highest bond strength observed when enamel treated with both etchant and bonding agent i.e. 2.72 (0.43) & 2.97 (0.19) for Relyx U200 and Elite cement. When alone etchant and bonding agent were applied alone bond strength is 2.19 (0.18) & 2.24 (0.47) for Relyx U200, and 2.38 (0.27) 2.49 (0.16) for Max-cem elite. Mean bond strength was higher in case of Max-cem Elite as compared to RelyX U200 resin cement, although differences were non–significant (p > 0.05). Conclusion Surface treatment of enamel increases the bond strength of self adhesive resin cement. PMID:26894165

  4. An in vitro Evaluation of Shear Bond Strength of Adhesive Precoated Brackets

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    A S Sibi

    2014-01-01

    Full Text Available Newer materials have been introduced in the field of orthodontics to improve clinical efficacy as well as to simplify the technique. In an effort to reduce the time and steps to bond orthodontic attachments, adhesive precoated (APC brackets were introduced. In this study, an attempt is made to evaluate the shear bond strength (SBS and debonding behavior of APC brackets compared with uncoated ceramic brackets. A total of 60 human premolar teeth were divided into two groups of 30 each, bonded with APC ceramic brackets and uncoated ceramic brackets. Group I bonded with APC brackets as prescribed by the manufacturers and group II was bonded with conventional bonding using Turbobond. After bonding, sthe samples were kept in distilled water at 37°C for 24 hours and a universal testing mechine was used to apply an occlusal shear force at a speed of 0.5 mm/min. The shear bond strength of the groups was compared using Student t-test and the debonding behavior were compared using Mann-Whitney′s U test. Mean shear bond strength and standard deviation of the groups were group I - 9.09 ± 2.5 MPa and group II - 12.95 ± 2.81 MPa. There were significant differences in bond strength observed between the two groups. The debonding behavior showed an adhesive remnant index score of 0.90 ± 0.08 for group I and 1.10 ± 0.04 for group II, which indicates there is significant difference between each other. When considering the values required for optimum bond strength, APC brackets in this study showed adequate bond strength and could be used for routine clinical use.

  5. Influence of glass particle size of resin cements on bonding to glass ceramic: SEM and bond strength evaluation.

    Science.gov (United States)

    Valentini, Fernanda; Moraes, Rafael R; Pereira-Cenci, Tatiana; Boscato, Noéli

    2014-05-01

    This study investigated the effect of the filler particle size (micron or submicron) of experimental resin cements on the microtensile bond strength to a glass-ceramic pretreated with hydrofluoric acid (HFA) etching or alumina airborne-particle abrasion (AA). Cements were obtained from a Bis-GMA/TEGDMA mixture filled with 60 mass% micron-sized (1 ± 0.2 µm) or submicron-sized (180 ± 30 µm) Ba-Si-Al glass particles. Ceramic blocks (PM9; VITA) were treated with 10% HFA for 60 s or AA for 15 s. Silane and adhesive were applied. Ceramic blocks were bonded to resin composite blocks (Z250; 3M ESPE) using one of the cements. Bonded specimens were sectioned into beams (n = 20/group) and subjected to microtensile bond strength tests. Data were analyzed using ANOVA and Student-Newman-Keuls' tests (5%). Failure modes were classified under magnification. Morphologies of the treated ceramic surfaces and bonded interfaces were evaluated by scanning electron microscopy. The HFA-submicron group had lower bond strengths than the other groups. All AA-submicron specimens debonded prematurely. Mixed failures were predominant for HFA groups, whereas interfacial failures predominated for AA groups. SEM revealed a honeycomb-like aspect in the HFA-treated ceramic, whereas the AA-treated groups showed an irregular retentive pattern. Continuity of cement infiltration along the bonded interface was more uniform for HFA-treated compared to AA-treated specimens. Cracks toward the bulk of the ceramic were observed in AA-treated specimens. Particle size significantly influenced the ceramic bond strength, whereas surface treatment had a minor effect. Copyright © 2014 Wiley Periodicals, Inc.

  6. Shear bond strength of self-etch and total-etch bonding systems at different dentin depths

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    Ana Carolina Maito Villela-Rosa

    2011-04-01

    Full Text Available The purpose of this study was to evaluate the dentin shear bond strength of four adhesive systems (Adper Single Bond 2, Adper Prompt L-Pop, Magic Bond DE and Self Etch Bond in regards to buccal and lingual surfaces and dentin depth. Forty extracted third molars had roots removed and crowns bisected in the mesiodistal direction. The buccal and lingual surfaces were fixed in a PVC/acrylic resin ring and were divided into buccal and lingual groups assigned to each selected adhesive. The same specimens prepared for the evaluation of superficial dentin shear resistance were used to evaluate the different depths of dentin. The specimens were identified and abraded at depths of 0.5, 1.0, 1.5 and 2.0 mm. Each depth was evaluated by ISO TR 11405 using an EMIC-2000 machine regulated at 0.5 mm/min with a 200 Kgf load cell. We performed statistical analyses on the results (ANOVA, Tukey and Scheffé tests. Data revealed statistical differences (p < 0.01 in the adhesive and depth variation as well as adhesive/depth interactions. The Adper Single Bond 2 demonstrated the highest mean values of shear bond strength. The Prompt L-Pop product, a self-etching adhesive, revealed higher mean values compared with Magic Bond DE and Self Etch Bond adhesives, a total and self-etching adhesive respectively. It may be concluded that the shear bond strength of dentin is dependent on material (adhesive system, substrate depth and adhesive/depth interaction.

  7. Manufacturing process for the metal ceramic hybrid fuel cladding tube

    International Nuclear Information System (INIS)

    Jung, Yang Il; Kim, Sun Han; Park, Jeong Yong

    2012-01-01

    For application in LWRs with suppressed hydrogen release, a metal-ceramic hybrid cladding tube has been proposed. The cladding consists of an inner zirconium tube and outer SiC fiber matrix SiC ceramic composite. The inner zirconium allows the matrix to remain fully sealed even if the ceramic matrix cracks through. The outer SiC composite can increase the safety margin by taking the merits of the SiC itself. However, it is a challenging task to fabricate the metal-ceramic hybrid tube. Processes such as filament winding, matrix impregnation, and surface costing are additionally required for the existing Zr based fuel cladding tubes. In the current paper, the development of the manufacturing process will be introduced

  8. Manufacturing process for the metal ceramic hybrid fuel cladding tube

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yang Il; Kim, Sun Han; Park, Jeong Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-10-15

    For application in LWRs with suppressed hydrogen release, a metal-ceramic hybrid cladding tube has been proposed. The cladding consists of an inner zirconium tube and outer SiC fiber matrix SiC ceramic composite. The inner zirconium allows the matrix to remain fully sealed even if the ceramic matrix cracks through. The outer SiC composite can increase the safety margin by taking the merits of the SiC itself. However, it is a challenging task to fabricate the metal-ceramic hybrid tube. Processes such as filament winding, matrix impregnation, and surface costing are additionally required for the existing Zr based fuel cladding tubes. In the current paper, the development of the manufacturing process will be introduced.

  9. Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Claudia Tavares Machado

    2012-01-01

    Conclusions: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.

  10. Metallized ceramic vacuum pipe for particle beams

    International Nuclear Information System (INIS)

    Butler, B.L.; Featherby, M.

    1990-01-01

    A ceramic vacuum chamber segment in the form of a long pipe of rectangular cross section has been assembled from standard shapes of alumina ceramic using glass bonding techniques. Prior to final glass bonding, the internal walls of the pipe are metallized using an electroplating technology. These advanced processes allow for precision patterning and conductivity control of surface conducting films. The ability to lay down both longitudinal and transverse conductor patterns separated by insulating layers of glass give the accelerator designer considerable freedom in tailoring longitudinal and transverse beam pipe impedances. Assembly techniques of these beam pipes are followed through two iterations of semi-scale pipe sections made using candidate materials and processes. These demonstrate the feasibility of the concepts and provide parts for electrical characterization and for further refinement of the approach. In a parallel effort, a variety of materials, joining processes and assembly procedures have been tried to assure flexibility and reliability in the construction of 10-meter long sections to any required specifications

  11. Shear Bond Strength of a Novel Porcelain Repair System for ...

    African Journals Online (AJOL)

    2018-04-04

    Apr 4, 2018 ... ceramic restorations are cemented with resin cements, removing ... causes physical alteration to increase the bonding of the resin to the ceramic ..... Static and fatigue mechanical behavior of three dental CAD/CAM ceramics.

  12. The esthetic metal-ceramic margin: a comparison of techniques.

    Science.gov (United States)

    Prince, J; Donovan, T

    1983-08-01

    Metal-ceramic crowns with all-porcelain labial margins may have esthetic and biologic advantages. Several techniques for making these restorations have been described in the prosthodontic literature. The authors used all the techniques and compared the results in terms of quality and degree of difficulty in construction. Clinically acceptable results can be achieved with all described techniques. The advantages and disadvantages of each method are summarized in Table I.

  13. Collarless metal ceramic restorations to obscure the umbrella effect

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    Afroz Shaista

    2010-01-01

    Full Text Available Esthetics with porcelain fused to metal restoration in the anterior region can be adversely affected due to the inadequate teeth preparations and design of the prosthesis. We presented here a case report where esthetics was compromised due to darkening of the interdental papilla and marginal gingival and overcontoured restorations in relation to porcelain fused to metal restorations. Good esthetic results were obtained by using basic principles of tooth preparation and using collarless metal ceramic restorations.

  14. Ion-plated metal/ceramic interfaces

    International Nuclear Information System (INIS)

    Rigsbee, J.M.; Scott, P.A.; Knipe, R.K.; Ju, C.P.; Hock, V.F.

    1986-01-01

    Elemental Cu and Ti films have been deposited onto magnesia-alumina-silica ceramic substrates with a plasma-aided physical vapour deposition (ion-plating) process. Modifications in the structure and chemistry of the film, interface and substrate regions were investigated as a function of deposition process parameters (eg applied bias, voltage and current). The strength of the Cu/ceramic interface was found to be strongly influenced by both applied substrate bias voltage and substrate roughness. Films deposited with an applied substrate bias showed increasing adhesive strength with increasing bias. Microchemical analysis indicated that this enhanced adhesion is directly correlated with the development of a chemically graded interface region. The adhesive strength of the ion plated Cu films was also found to be improved with increasing substrate smoothness. The behaviour of Ti was found to be quite different from that of Cu. Ti generally has superior adhesion. This adhesion decreased for films deposited with a high bias voltage/current. From interfacial TEM it is shown that this is due to the formation of a compound at the Ti/ceramic interface. The thickness of this compound is important in adhesion. (UK)

  15. Microtensile bond strength of three simplified adhesive systems to caries-affected dentin.

    Science.gov (United States)

    Scholtanus, J D; Purwanta, Kenny; Dogan, Nilgun; Kleverlaan, Cees J; Feilzer, Albert J

    2010-08-01

    The purpose of the study was to determine the microtensile bond strength of three different simplified adhesive systems to caries-affected dentin. Fifteen extracted human molars with primary carious lesions were ground flat until dentin was exposed. Soft caries-infected dentin was excavated with the help of caries detector dye. On the remaining hard dentin, a standardized smear layer was created by polishing with 600-grit SiC paper. Teeth were divided into three groups and treated with one of the three tested adhesives: Adper Scotchbond 1 XT (3M ESPE), a 2-step etch-andrinse adhesive, Clearfil S3 Bond (Kuraray), a 1-step self-etching or all-in-one adhesive, and Clearfil SE Bond (Kuraray), a 2-step self-etching adhesive. Five-mm-thick composite buildups (Z-250, 3M ESPE) were built and light cured. After water storage for 24 h at 37ºC, the bonded specimens were sectioned into bars (1.0 x 1.0 mm; n = 20 to 30). Microtensile bond strength of normal dentin specimens and caries-affected dentin specimens was measured in a universal testing machine (crosshead speed = 1 mm/min). Data were analyzed using two-way ANOVA and Tukey's post-hoc test (p adhesives were found. Adper Scotchbond 1 XT and Clearfil S3 Bond showed significantly lower bond strength values to caries-affected dentin. For Clearfil SE Bond, bond strength values to normal and caries-affected dentin were not significantly different. All the tested simplified adhesives showed similar bond strength values to normal dentin. For the tested 2-step etch-and-rinse adhesive and the all-in-one adhesive, the bond strength values to caries-affected dentin were lower than to normal dentin.

  16. Effect of Nanofiller Addition to an Experimental Dentin Adhesive on Microtensile Bond Strength to Human Dentin

    Directory of Open Access Journals (Sweden)

    SH. Kasraei

    2009-06-01

    Full Text Available Objective: The purpose of the study was to evaluate the influence of adding nanofiller particles to a dentin bonding agent on resin-dentin bond strength.Materials and Methods: Fifty-four human intact premolar teeth were divided in to 6 groups of nine. The teeth were ground on occlusal surfaces and polished with 320 and then 600 grit silicon carbide papers. An experimental bonding system based on acetone/alcoholsolvent was provided with filler contents of 0.0, 0.5, 1.0, 2.5, 5.0, and 10.0 weight percent fumed silica nanofiller. After dentin surface etching, rinsing and blot drying, the experimentalbonding agents were applied to dentin surface. A composite resin was, then,bonded to the dentin on the bonding agent. The specimens were thermocycled for 500 cycles and sectioned in stick form. After two week of storage in distilled water, resin-dentin microtensile bond strength of the specimens was measured. Data were analyzed by one way ANOVA and DunnettT3 tests.Results: Bond strength to dentin was significantly affected by the filler level. Minimum and maximum resin-microtensile bond strength was in the experimental bonding agent with no filler (5.88 MPa and with filler level of 1.0 weight percent (15.15 MPa, respectively,and decreased with the increase of filler content down to 8.95 MPa for the filler level of 10.0 weight percent.Conclusion: Filler content seems to be one of the important factors influencing the bond strength of dental adhesives. Maximum dentin bond strength was obtained with 1% silanized nanofiller silica added to experimental adhesive system.

  17. Influence of surface treatments on the shear bond strength of orthodontic brackets to porcelain

    Science.gov (United States)

    Wang, Cong; Zeng, Jishan; Wang, Shaoan; Yang, Zheng; Huang, Qian; Chen, Pixiu; Zhou, Shujuan; Liu, Xiaoqing

    2008-11-01

    The purpose of this study was to investigate the effect of various surface treatments after different storage time and thermocycling on the shear bond strength of orthodontic brackets to the feldspathic porcelain surfaces. 128 disc-shaped porcelain specimens were randomly assigned to the following surface treatments: 9.6% HFA, 9.6% HFA combined with silane, 50 μ aluminum trioxide sandblasting followed by silane and application of silane after 37% phosphoric acid. Metal or ceramic brackets were bonded onto each treated porcelain facet with light cured resin. The samples were stored in 37 °C water 1 day or 7 days, thermocycled 500 times from 5 to 55 °C. The shear bond strengths were measured (1 mm/min), and statistically analyzed. The bond failure sites were classified according to ARI system. The surface of the glazed, sandblasted, hydrofluoric and phosphoric acid etched porcelain were examined with SEM. All groups achieved reasonable bond strengths to withstand the application of orthodontic forces. Water storage for 7 days caused lower shear bond strength than that of 1 day. But there is no statistically significant difference between the two groups. The mean shear bond strength provided by ceramic bracket with mechanical retention had no statistical difference with that of metal bracket. Therefore, the optimal treatment for orthodontic brackets bonding to feldspathic porcelain was to apply phosphoric acid combined with silane.

  18. Effect of newer antioxidants on the bond strength of composite on bleached enamel

    Directory of Open Access Journals (Sweden)

    M Manoharan

    2016-01-01

    Full Text Available Aim: The study aims to evaluate the effect of the application of two antioxidants on the bond strength of composite resin to bleached enamel. Materials and Methods: Eighty enamel surfaces were obtained from forty human extracted premolars. Specimens were randomly divided into four groups (n = 20. Group 1: No bleaching (control; Group 2a: Bleaching with 15% carbamide peroxide gel; Group 2b: Bleaching, followed by application of 10% sodium ascorbate gel; Group 2c: Bleaching, followed by application of 5% proanthocyanidin agent. Surfaces were etched followed by application of total etch bonding system, and composite resin cylinders were bonded. Specimens were tested for shear bond strength. Statistical Analysis Used: One-way analysis of variance was used for multiple group comparison and post hoc Tukey′s test for individual group-wise comparison. Results: Significantly higher shear bond strength values were observed in Group 2c and 2b as compared with Group 1 and 2a (P < 0.05. Among the antioxidants, Group 2c showed significantly higher shear bond strength values than Group 2b (P < 0.05. Conclusion: It can be concluded that the use of antioxidant before bonding procedures on bleached enamel completely neutralizes the deleterious effects of bleaching and increases the bond strength significantly.

  19. Eroded dentin does not jeopardize the bond strength of adhesive restorative materials

    Directory of Open Access Journals (Sweden)

    Janaina Barros Cruz

    2012-08-01

    Full Text Available This in vitro study evaluated the bond strength of adhesive restorative materials to sound and eroded dentin. Thirty-six bovine incisors were embedded in acrylic resin and ground to obtain flat buccal dentin surfaces. Specimens were randomly allocated in 2 groups: sound dentin (immersion in artificial saliva and eroded dentin (pH cycling model - 3× / cola drink for 7 days. Specimens were then reassigned according to restorative material: glass ionomer cement (KetacTM Molar Easy Mix, resin-modified glass ionomer cement (VitremerTM or adhesive system with resin composite (Adper Single Bond 2 + Filtek Z250. Polyethylene tubes with an internal diameter of 0.76 mm were placed over the dentin and filled with the material. The microshear bond test was performed after 24 h of water storage at 37ºC. The failure mode was evaluated using a stereomicroscope (400×. Bond strength data were analyzed with two-way ANOVA and Tukey's post hoc tests (α = 0.05. Eroded dentin showed bond strength values similar to those for sound dentin for all materials. The adhesive system showed the highest bond strength values, regardless of the substrate (p < 0.0001. For all groups, the adhesive/mixed failure prevailed. In conclusion, adhesive materials may be used in eroded dentin without jeopardizing the bonding quality. It is preferable to use an etch-and-rinse adhesive system because it shows the highest bond strength values compared with the glass ionomer cements tested.

  20. Effects of surface treatment of provisional crowns on the shear bond strength of brackets

    Directory of Open Access Journals (Sweden)

    Josiane Xavier de Almeida

    2013-08-01

    Full Text Available OBJECTIVE: To assess the adhesive resistance of metallic brackets bonded to temporary crowns made of acrylic resin after different surface treatments. METHODS: 180 specimens were made of Duralay and randomly divided into 6 groups (n = 30 according to surface treatment and bonding material: G1 - surface roughening with Soflex and bonding with Duralay; G2 - roughening with aluminum oxide blasting and bonding with Duralay; G3 - application of monomer and bonding with Duralay; G4 - roughening with Soflex and bonding with Transbond XT; G5 - roughening with aluminum oxide blasting and bonding with Transbond XT and G6: application of monomer and bonding with Transbond. The results were statistically assessed by ANOVA/Games-Howell. RESULTS: The means (MPa were: G1= 18.04, G2= 22.64, G3= 22.4, G4= 9.71, G5= 11.23, G6= 9.67. The Adhesive Remnant Index (ARI ranged between 2 and 3 on G1, G2 and G3 whereas in G4, G5 and G6 it ranged from 0 to 1, showing that only the material affects the pattern of adhesive flaw. CONCLUSION: The surface treatment and the material influenced adhesive resistance of brackets bonded to temporary crowns. Roughening by aluminum blasting increased bond strength when compared to Soflex, in the group bonded with Duralay. The bond strength of Duralay acrylic resin was superior to that of Transbond XT composite resin.

  1. Shear Bond Strength of Orthodontic Brackets to Tooth Enamel After Treatment With Different Tooth Bleaching Methods.

    Science.gov (United States)

    Vahid Dastjerdi, Elahe; Khaloo, Negar; Mojahedi, Seyed Masoud; Azarsina, Mohadese

    2015-11-01

    Bleaching treatments decrease shear bond strength between orthodontic brackets and teeth; although definite results have not been reported in this regard. This study determined the effects of different bleaching protocols on the shear bond strength of orthodontic brackets to teeth. This experimental study was performed in Iran. Forty-eight extracted human premolars were randomly assigned into four groups. In the control group, no bleaching treatment was performed. In groups 2 - 4, the bleaching procedures were performed using carbamide peroxide 45%, carbamide peroxide 20% and diode laser, respectively. Two weeks later, brackets were bonded to teeth and thermocycled. The shear bond strengths of the brackets to the teeth were measured. Data was analyzed by one-way ANOVA and Dunnett post-hoc test. Shear bond strength of the brackets to the teeth were 10.54 ± 1.51, 6.37 ± 0.92, 7.67 ± 1.01 and 7.49 ± 1.19 MPa, in groups 1 - 4, respectively. Significant differences were found between control group and all other groups (P brackets to the teeth. 45% carbamide peroxide had a more significant effect on bond strength compared to 20% carbamide peroxide. The difference in bond strength was not significant between laser group and either carbamide peroxide groups.

  2. Shear Bond Strengths and Morphological Evaluation of Filled and Unfilled Adhesive Interfaces to Enamel and Dentine

    Science.gov (United States)

    Mortazavi, Vajihesadat; Fathi, Mohammadhosein; Ataei, Ebrahim; Khodaeian, Niloufar; Askari, Navid

    2012-01-01

    In this laboratory study shear bond strengths of three filled and one unfilled adhesive systems to enamel and dentine were compared. Forty-eight extracted intact noncarious human mandibular molars were randomly assigned to two groups of 24 one for bonding to enamel and the other for bonding to dentine. Buccal and lingual surfaces of each tooth were randomly assigned for application of each one of filled (Prime & Bond NT (PBNT), Optibond Solo Plus (OBSP), and Clearfil SE Bond (CSEB)) and unfilled (Single Bond (SB)) adhesive systems (n = 12). A universal resin composite was placed into the translucent plastic cylinders (3 mm in diameter and 2 mm in length) and seated against the enamel and dentine surfaces and polymerized for 40 seconds. Shear bond strength was determined using a universal testing machine, and the results were statistically analyzed using two-way ANOVA, one-way ANOVA, t-test, and Tukey HSD post hoc test with a 5% level of significance.There were no statistically significant differences in bond strength between the adhesive systems in enamel, but CSEB and SB exhibited significantly higher and lower bond strength to dentine, respectively, than the other tested adhesive systems while there were no statistically significant differences between PBNT and OBSP. PMID:23209471

  3. Shear Bond Strengths and Morphological Evaluation of Filled and Unfilled Adhesive Interfaces to Enamel and Dentine

    Directory of Open Access Journals (Sweden)

    Vajihesadat Mortazavi

    2012-01-01

    Full Text Available In this laboratory study shear bond strengths of three filled and one unfilled adhesive systems to enamel and dentine were compared. Forty-eight extracted intact noncarious human mandibular molars were randomly assigned to two groups of 24 one for bonding to enamel and the other for bonding to dentine. Buccal and lingual surfaces of each tooth were randomly assigned for application of each one of filled (Prime & Bond NT (PBNT, Optibond Solo Plus (OBSP, and Clearfil SE Bond (CSEB and unfilled (Single Bond (SB adhesive systems (n=12. A universal resin composite was placed into the translucent plastic cylinders (3 mm in diameter and 2 mm in length and seated against the enamel and dentine surfaces and polymerized for 40 seconds. Shear bond strength was determined using a universal testing machine, and the results were statistically analyzed using two-way ANOVA, one-way ANOVA, t-test, and Tukey HSD post hoc test with a 5% level of significance.There were no statistically significant differences in bond strength between the adhesive systems in enamel, but CSEB and SB exhibited significantly higher and lower bond strength to dentine, respectively, than the other tested adhesive systems while there were no statistically significant differences between PBNT and OBSP.

  4. Influence of dentinal regions on bond strengths of different adhesive systems.

    Science.gov (United States)

    Ozer, F; Unlü, N; Sengun, A

    2003-06-01

    This in vitro study assessed comparatively the shear bond strengths of three composite resins, 3M Valux Plus (3MVP), Herculite (H), Clearfil AP-X (CAP-X), a polyacid modified composite resin Dyract (D), and a resin modified glass-ionomer materials Vitremer (V), to cervical and buccal dentine regions of extracted human molar teeth. Four different bonding systems, 3M ScotchBond Multipurpose (SB), Clearfil Liner Bond 2 (LB2), Opti Bond (OB), and Prime & Bond 2.1 (PB 2.1) were used with the manufacturer's respective composite and compomer materials. One hundred freshly extracted mandibular molar teeth were selected for this study. Flat buccal dentine surfaces were created on 50 teeth and cylindrical rods of the five materials were bonded to the dentine surfaces. For assessment of cervical bond strengths, the materials were bonded to mesial and distal enamel bordered occlusal dentinal surfaces of the remaining 50 teeth. The five groups of restorative procedures were applied as follows; Group 1: SB + 3MVP, Group 2: LB2 + CAP-X, Group 3: OB + H, Group 4: PB2.1 + D, Group 5: Vitremer primer (VP) VP + V. Each restorative procedure thus had 20 specimens (10 buccal + 10 cervical). After 24 h of water storage (37 degrees C), the specimens were tested on a Universal Testing machine in shear with a cross head speed of 0.5 mm min-1. The bond strength values were calculated in MPa and the results were evaluated statistically using Kruskal-Wallis one-way/anova and Mann-Whitney U-tests. It was found that the bond strengths of SB + 3MVP, LB2 + CAP-X and VP + V to buccal dentine surfaces were significantly stronger (P 0.05). Vitremer was found the least successful adhesive material in terms of shear bond strength on both buccal and occluso-cervical dentine surfaces.

  5. Microshear bond strength of self-etching systems associated with a hydrophobic resin layer.

    Science.gov (United States)

    De Vito Moraes, André Guaraci; Francci, Carlos; Carvalho, Ceci Nunes; Soares, Silvio Peixoto; Braga, Roberto Ruggiero

    2011-08-01

    To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according to manufacturers' instructions, associated or not with a hydrophobic layer of unfilled resin. Six self-etching adhesives (Clearfil SE Bond, Kuraray Medical; AdheSE, Ivoclar Vivadent; Xeno III, Dentsply; I Bond, Heraeus-Kulzer; Bond Force, Tokuyama; Futurabond DC, Voco) were tested. The labial dentin of sixty bovine incisors was exposed, and the teeth were divided into two groups according to the application or not of an extra hydrophobic resin layer (Scotchbond Multi Purpose Plus, bottle 3). Six composite cylinders (Filtek Z250, 3M ESPE) were built up on each treated surface. Specimens were stored in distilled water at 37ºC for 24 h and then subjected to the microshear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. Microshear bond strength values were analyzed by 2-way ANOVA and Tukey's post-hoc test. Failure mode was determined using a stereomicroscope under 20X magnification. The application of the hydrophobic resin layer did not affect bond strength, except for AdheSE. However, the bond strengths with the hydrophobic layer were similar among the six tested systems (Clearfil: 17.1 ± 7.9; AdheSE: 14.5 ± 7.1; Xeno lll: 12.8 ± 7.7; I Bond: 9.5 ± 5.8; Bond Force: 17.5 ± 4.1; Futurabond: 7.7 ± 2.3). When used as recommended by the manufacturers, Bond Force presented statistically higher bond strength than AdheSE and I Bond (p AdheSE 1.6 ± 1.6; Xeno lll: 9.0 ± 3.8; I Bond: 3.0 ± 1.5; Bond Force: 14 ± 3.9; Futurabond: 8.8 ± 3.8). Failure mode was predominantly adhesive. The bond strength of the self-etching systems tested was not significantly affected by the application of a hydrophobic layer, but a significant improvement was observed in AdheSE.

  6. Evaluation of the anti-cariogenic potential and bond strength to enamel of different fluoridated materials used for bracket bonding

    Directory of Open Access Journals (Sweden)

    Sérgio Ricardo da SILVA

    2017-05-01

    Full Text Available Abstract Objective To evaluate the in vitro and in situ anti-cariogenic potential and bond strength to enamel of materials containing fluoride (F, used for bracket bonding: Transbond XT (GT, negative control, Transbond Plus Color Change (GTF, Transbond-Self-Etching Primer (GSAF and Vitremer (GV, positive control. Material and method In the in vitro study, the specimens were premolars with bonded brackets (n=12/group. After pH cycling, the F release, bond strength, fracture mode and presence of white spot lesions were assessed. In the in situ study, the specimens were enamel fragments with bonded brackets (n=12/group. Twelve volunteers wore palatal appliances in 4 phases, with cariogenic challenge. Bond strength, fracture mode and change in surface hardness (%SH were determined. Result Relative to the in vitro study, F release (ppm was: GT=0.257±0.068c; GTF=0.634±0.100b; GSAF=0.630±0.067b; GV=2.796±1.414a. Only GV showed no white spot lesions. Bond strength values (MPa were GT=7.62±7.18a; GTF=5.15±6.91ab; GSAF=3.42±2.97bc; GV=2.87±2.09c. Adhesive fracture was the most frequent type, except for GTF. In the in situ study, %SH was: GT=-56.0±18.3a; GTF=-57.6±11.9a; GSAF=-57.1±11.3a; GV=-52.4±25.8a. Bond strength values were GT=9.5±4.4a; GTF=11.1±5.9a; GSAF=13.2± 6.6a; GV=6.6±4.0a. Cohesive fracture in material was the most frequent type, except for GTF. Conclusion Vitremer (GV showed the highest anti-cariogenic potential in the in vitro study. However, it was not confirmed by the in situ study. Regarding bond strength values from the in situ study, all materials were shown to be adequate for clinical practice.

  7. The effect of pretreatment with fluoride on the tensile strength of orthodontic bonding

    International Nuclear Information System (INIS)

    Wang, W.N.; Sheen, D.H.

    1991-01-01

    White spot decalcifications and caries occurring adjacent to bonded orthodontic brackets have long been a concern to orthodontists. One procedure suggested to overcome this problem is fluoride treatment prior to bonding. The purpose of this study was to compare the tensile bond strength of orthodontic self-cured resin from Concise on teeth rinsed 4 minutes in 1.23% APF with untreated controls. Measurements were made on an Instron machine. Debonding interfaces were observed with a scanning electron microscope and energy dispersive x-ray spectrometry. Distributions were calculated. The tensile bond strengths of the fluoride-treated teeth and the untreated teeth were not significantly different. The debonding interfaces between resin and bracket base, within the resin itself, and between enamel and resin were similar in the two experimental groups. However, greater enamel detachment was seen within the fluoride pretreatment group. So while fluoride pretreatment does not significantly affect tensile bond strength, it may cause enamel detachment after debonding

  8. Coated steel rebar for enhanced concrete-steel bond strength and corrosion resistance.

    Science.gov (United States)

    2010-10-01

    This report summarizes the findings and recommendations on the use of enamel coating in reinforced concrete structures both for bond strength and : corrosion resistance of steel rebar. Extensive laboratory tests were conducted to characterize the pro...

  9. Two component injection moulding: an interface quality and bond strength dilemma

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2008-01-01

    on quality parameters of the two component parts. Most engineering applications of two component injection moulding calls for high bond strength between the two polymers, on the other hand a sharp and well-defined interface between the two polymers are required for applications like selective metallization...... of polymers, parts for micro applications and also for the aesthetic purpose of the final product. The investigation presented in this paper indicates a dilemma between obtaining reasonably good bond strength and at the same time keeping the interface quality suitable for applications. The required process...... conditions for a sharp and well-defined interface are exactly the opposite of what is congenial for higher bond strength. So in the production of two component injection moulded parts, there is a compromise to make between the interface quality and the bond strength of the two polymers. Also the injection...

  10. Retentive Shear Strengths of Various Bonding Attachment Bases: An in vitro Study

    Directory of Open Access Journals (Sweden)

    Abhishek Goyal

    2013-01-01

    Conclusion: Gemini brackets provided the best bond strengths clinically, followed by Mini Diagonali, Nu-Edge, Mini Twin, Mini Diamond and the Sapphire brackets in decreasing order as measured using the Weibull analysis.

  11. Immediate repair bond strengths of microhybrid, nanohybrid and nanofilled composites after different surface treatments

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    Objectives: To evaluate immediate repair bond strengths and failure types of resin composites with and without surface conditioning and characterize the interacting composite surfaces by their surface composition and roughness. Methods: Microhybrid, nanohybrid and nanofilled resin composites were

  12. Effect of hot-humid exposure on static strength of adhesive-bonded aluminum alloys

    Directory of Open Access Journals (Sweden)

    Rui Zheng

    2015-09-01

    Full Text Available The effect of hot-humid exposure (i.e., 40 °C and 98% R.H. on the quasi-static strength of the adhesive-bonded aluminum alloys was studied. Test results show that the hot-humid exposure leads to the significant decrease in the joint strength and the change of the failure mode from a mixed cohesive and adhesive failure with cohesive failure being dominant to adhesive failure being dominant. Careful analyses of the results reveal that the physical bond is likely responsible for the bond adhesion between L adhesive and aluminum substrates. The reduction in joint strength and the change of the failure mode resulted from the degradation in bond adhesion, which was primarily attributed to the corrosion of aluminum substrate. In addition, the elevated temperature exposure significantly accelerated the corrosion reaction of aluminum, which accelerated the degradation in joint strength.

  13. Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings.

    Science.gov (United States)

    Tsumita, M; Kokubo, Y; Kano, T

    2012-09-01

    The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling.

  14. The influence of salivary contamination on shear bond strength of dentin adhesive systems.

    Science.gov (United States)

    Park, Jeong-won; Lee, Kyung Chae

    2004-01-01

    This study evaluated the influence of salivary contamination during dentin bonding procedures on shear bond strength and investigated the effect of contaminant-removing treatments on the recovery of bond strength for two dentin bonding agents. One hundred and ten human molars were embedded in cylindrical molds with self-curing acrylic resin. The occlusal dentin surface was exposed by wet grinding with #800 silicon carbide abrasive paper. The teeth were divided into five groups for One-step (OS) (BISCO, Inc) and six groups for Clearfil SE Bond (SE) (Kuraray Co, Ltd, Osaka, Japan). For One-step, the grinding surface was treated with 32% phosphoric acid; BAC (BISCO Inc) and divided into five groups: OS control group (uncontaminated), OS I (salivary contamination, blot dried), OS II (salivary contamination, completely dried), OS III (salivary contamination, wash and blot dried) and OS IV (salivary contamination, re-etching for 10 seconds, wash and blot dried). For SE bond, the following surface treatments were done: SE control group (primer applied to the fresh dentin surface), SE I (after salivary contamination, primer applied), SE II (primer, salivary contamination, dried), SE III (primer, salivary contamination, wash and dried), SE IV (after procedure of SE II, re-application of primer) and SE V (after procedure of SE III, re-application of primer). Each bonding agent was applied and light cured for 10 seconds. Clearfil AP-X (Kuraray Co, Ltd) composite was packed into the Ultradent mount jig mold and light cured for 40 seconds. The bonded specimens were stored for 24 hours in a 37 degrees C waterbath. The shear bond strengths were measured using an Instron testing machine (Model 4202, Instron Corp). The data for each group were subjected to one-way ANOVA followed by the Newman-Keuls test to make comparisons among the groups. The results were as follows: In the One-step groups, the OS II group showed statistically significant lower shear bond strength than the OS

  15. Shear bond strength of two 2-step etch-and-rinse adhesives when bonding ceramic brackets to bovine enamel.

    Science.gov (United States)

    Godard, Marion; Deuve, Benjamin; Lopez, Isabelle; Hippolyte, Marie-Pascale; Barthélemi, Stéphane

    2017-09-01

    The present study assessed a fracture analysis and compared the shear bond strength (SBS) of two 2-step etch-and-rinse (E&R) adhesives when bonding ceramic orthodontic brackets to bovine enamel. Thirty healthy bovine mandibular incisors were selected and were equally and randomly assigned to 2 experimental groups. Ceramic brackets (FLI Signature Clear ® , RMO) were bonded onto bovine enamel using an adhesive system. In group 1 (n=15), the conventional E&R adhesive (OrthoSolo ® +Enlight ® , Ormco) was used, and in group 2 (n=15), the new E&R adhesive limited to ceramic bracket bonding (FLI ceramic adhesive ® : FLI sealant resin ® +FLI adhesive paste ® , RMO) was used. In order to obtain appropriate enamel surfaces, the vestibular surfaces of mandibular bovine incisors were flat ground. After bonding, all the samples were stored in distilled water at room temperature for 21 days and subsequently tested for SBS, using the Instron ® universal testing machine. The Adhesive Remnant Index (ARI) scores were evaluated. Failure modes were assessed using optical microscopy at magnification ×40. A statistic data analysis was performed using the Mann-Whitney U-test (Penamel/adhesive interface. A statistically significant difference was found for the ARI scores between the two groups (P=0.00996). Only two fractured brackets, which remained bonded onto the bovine enamel, were reported. Both occurred in group 1. When bonded to ceramic brackets, FLI ceramic adhesive ® (RMO) was demonstrated to be very predictable and safe for clinical application in enamel bonding, whereas the results obtained with the conventional adhesive system (OrthoSolo ® +Enlight ® , Ormco) were less reproducible and revealed slightly excessive shear bond strength values. Copyright © 2017 CEO. Published by Elsevier Masson SAS. All rights reserved.

  16. Dentin bond strength and degree of conversion evaluation of experimental self-etch adhesive systems

    OpenAIRE

    Yazdi, Fatemeh-Maleknejad; Moosavi, Horieh; Atai, Mohammad; Zeynali, Mahsa

    2015-01-01

    Background The aim of this study was to investigate the effect of different concentrations of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) monomer in one-step self-etch experimental adhesives on dentinal microshear bond strength (?SBS), their degree of conversion and bonded micro structure. Material and Methods Composite resin cylinders (Clearfil AP-X) were bonded on human sound molar dentinal surfaces by using five experimental one-step self-etching adhesives (1-SEAs) containing 0% ...

  17. Shear bond strength of metallic and ceramic brackets using color change adhesives

    Directory of Open Access Journals (Sweden)

    Aisha de Souza Gomes Stumpf

    2013-04-01

    Full Text Available OBJECTIVE: To determine the shear bond strength of orthodontic brackets using color change adhesives that are supposed to aid in removing excess of bonding material and compare them to a traditional adhesive. METHODS: Ninety metallic and ninety ceramic brackets were bonded to bovine incisors using two color change adhesives and a regular one. A tensile stress was applied by a universal testing machine. The teeth were observed in a microscope after debonding in order to determine the Adhesive Remnant Index (ARI. RESULTS: The statistical analysis (ANOVA, Tukey, and Kruskall-Wallis tests demonstrated that the mean bond strength presented no difference when metallic and ceramic brackets were compared but the bond resistance values were significantly different for the three adhesives used. The most common ARI outcome was the entire adhesive remaining on the enamel. CONCLUSIONS: The bond strength was similar for metallic and ceramic brackets when the same adhesive system was used. ARI scores demonstrated that bonding with these adhesives is safe even when ceramic brackets were used. On the other hand, bond strength was too low for orthodontic purposes when Ortho Lite Cure was used.

  18. The influence of water flow (reversal) on bond strength development in young masonry

    NARCIS (Netherlands)

    Groot, C.; Larbi, J.

    1999-01-01

    Water loss from the fresh mortar is believed to be related to mortar-brick bond strength development in masonry. Recent research on mortar-brick bond has shown that, particularly, effects of water flow on the composition and the hydration conditions of the mortar-brick interface have to be taken

  19. Assessing the effects of hydrogen peroxide bleaching agent on the shear bond strength of orthodontic brackets.

    Science.gov (United States)

    Andrighetto, Augusto Ricardo; de Leão Withers, Eduardo Henrique; Grando, Karlos Giovani; Ambrosio, Aldrieli Regina; Shimizu, Roberto Hideo; Melo, Ana Cláudia

    2016-01-01

    Tooth bleaching is, today, one of the most widespread cosmetic treatments in dental practice,  so it is important to determine whether it can interfere with orthodontic bonding or not. The aim of this study was to assess the in vitro effects of 35% hydrogen peroxide bleaching agent on the shear bond strength of orthodontic brackets. Forty-five upper bicuspids were divided into three groups (n = 15). In the control Group (C), the brackets were bonded without previous bleaching treatment. Group 1 (G1) was treated with 35% hydrogen peroxide bleaching agent 24 h before bracket bonding. Group 2 was also bleached, and the brackets were bonded after 30 days. The shear bond strength of the brackets was measured using an EMIC machine, and the results were analyzed by ANOVA. There were no statistically significant differences between the three groups (P > 0.05), with Group C showing a mean bond strength of 9.72 ± 2.63 MPa, G1 of 8.09 ± 2.63 MPa, and G2 of 11.15 ± 4.42 MPa. It was possible to conclude that 35% hydrogen peroxide bleaching agent does not affect the shear strength of orthodontic brackets bonded 24 h and 30 days after bleaching.

  20. Shear bond strength of metallic and ceramic brackets using color change adhesives.

    Science.gov (United States)

    Stumpf, Aisha de Souza Gomes; Bergmann, Carlos; Prietsch, José Renato; Vicenzi, Juliane

    2013-01-01

    To determine the shear bond strength of orthodontic brackets using color change adhesives that are supposed to aid in removing excess of bonding material and compare them to a traditional adhesive. Ninety metallic and ninety ceramic brackets were bonded to bovine incisors using two color change adhesives and a regular one. A tensile stress was applied by a universal testing machine. The teeth were observed in a microscope after debonding in order to determine the Adhesive Remnant Index (ARI). The statistical analysis (ANOVA, Tukey, and Kruskall-Wallis tests) demonstrated that the mean bond strength presented no difference when metallic and ceramic brackets were compared, but the bond resistance values were significantly different for the three adhesives used. The most common ARI outcome was the entire adhesive remaining on the enamel. The bond strength was similar for metallic and ceramic brackets when the same adhesive system was used. ARI scores demonstrated that bonding with these adhesives is safe even when ceramic brackets were used. On the other hand, bond strength was too low for orthodontic purposes when Ortho Lite Cure was used.

  1. Shear bond strength of orthodontic brackets and disinclusion buttons: effect of water and saliva contamination.

    Science.gov (United States)

    Sfondrini, Maria Francesca; Fraticelli, Danilo; Gandini, Paola; Scribante, Andrea

    2013-01-01

    The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons. 120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a) dry, (b) water contamination, and (c) saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values) and Chi squared test (ARI Scores). Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions. Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons.

  2. Effect of Enamel and Dentin Surface Treatment on the Self-Adhesive Resin Cement Bond Strength.

    Science.gov (United States)

    Mushashe, Amanda Mahmmad; Gonzaga, Carla Castiglia; Cunha, Leonardo Fernandes da; Furuse, Adilson Yoshio; Moro, Alexandre; Correr, Gisele Maria

    2016-01-01

    The aim of this study was to evaluate the effect of enamel and dentin surface treatment on the micro-shear bond strength of self-adhesive cement. Seventy-two extracted third molars had their crowns embedded in acrylic resin and worn to obtain a flat enamel or dentin surface. The enamel and dentin specimens were randomly assigned to 8 groups (n=12) that were based on surface treatment (11.5% polyacrylic acid solution or no treatment), substrate condition (wet or dry) and storage period (1 day or 90 days), and treated accordingly. Cylinders (1 × 1 mm) were fabricated using self-adhesive resin cement (RelyX U200) following the manufacturer's instructions. The specimens were stored in distilled water at 37 °C for either 1 day or 90 days and subjected to micro-shear bond strength test (EMIC DL 2000 at 0.5 mm/min). After this, the failure type of the specimens was determined. Data were subjected to statistical analysis (a=0.05). According to the results, the 11.5% polyacrylic acid application decreased the bond strength in both enamel and dentin samples. The moist groups showed higher bond strength than the dry ones, regardless of the substrate and surface treatment. Storage period did not influence bond strength. In conclusion, surface treatment with 11.5% polyacrylic acid and absence of moisture decreased the bond strength of the resin-cement (RelyU200), regardless of the storage period.

  3. Shear Bond Strength of Orthodontic Brackets and Disinclusion Buttons: Effect of Water and Saliva Contamination

    Science.gov (United States)

    Sfondrini, Maria Francesca; Fraticelli, Danilo; Gandini, Paola

    2013-01-01

    Purpose. The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons. Materials and Methods. 120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a) dry, (b) water contamination, and (c) saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values) and Chi squared test (ARI Scores). Results. Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions. Conclusions. Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons. PMID:23762825

  4. Shear Bond Strength of Orthodontic Brackets and Disinclusion Buttons: Effect of Water and Saliva Contamination

    Directory of Open Access Journals (Sweden)

    Maria Francesca Sfondrini

    2013-01-01

    Full Text Available Purpose. The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons. Materials and Methods. 120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a dry, (b water contamination, and (c saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values and Chi squared test (ARI Scores. Results. Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions. Conclusions. Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons.

  5. Enamel and dentin bond strengths of a new self-etch adhesive system.

    Science.gov (United States)

    Walter, Ricardo; Swift, Edward J; Boushell, Lee W; Braswell, Krista

    2011-12-01

    statement of problem:  Self-etch adhesives typically are mildly acidic and therefore less effective than etch-and-rinse adhesives for bonding to enamel.   The purpose of this study was to evaluate the enamel and dentin shear bond strengths of a new two-step self-etch adhesive system, OptiBond XTR (Kerr Corporation, Orange, CA, USA).   The labial surfaces of 80 bovine teeth were ground to create flat, 600-grit enamel or dentin surfaces. Composite was bonded to enamel or dentin using the new two-step self-etch system or a three-step etch-and-rinse (OptiBond FL, Kerr), two-step self-etch (Clearfil SE Bond, Kuraray America, Houston, TX, USA), or one-step self-etch adhesive (Xeno IV, Dentsply Caulk, Milford, DE, USA). Following storage in water for 24 hours, shear bond strengths were determined using a universal testing machine. The enamel and dentin data sets were subjected to separate analysis of variance and Tukey's tests. Scanning electron microscopy was used to evaluate the effects of each system on enamel.   Mean shear bond strengths to enamel ranged from 18.1 MPa for Xeno IV to 41.0 MPa for OptiBond FL. On dentin, the means ranged from 33.3 MPa for OptiBond FL to 47.1 MPa for Clearfil SE Bond. OptiBond XTR performed as well as Clearfil SE Bond on dentin and as well as OptiBond FL on enamel. Field emission scanning electron microscope revealed that OptiBond XTR produced an enamel etch pattern that was less defined than that of OptiBond FL (37.5% phosphoric acid) but more defined than that of Clearfil SE Bond or Xeno IV.   The new two-step self-etch adhesive system formed excellent bonds to enamel and dentin in vitro. OptiBond XTR, a new two-step self-etch adhesive system, is a promising material for bonding to enamel as well as to dentin. © 2011 Wiley Periodicals, Inc.

  6. Polar Flattening and the Strength of Halogen Bonding

    Czech Academy of Sciences Publication Activity Database

    Sedlák, Robert; Kolář, Michal H.; Hobza, Pavel

    2015-01-01

    Roč. 11, č. 10 (2015), s. 4727-4732 ISSN 1549-9618 R&D Projects: GA ČR GBP208/12/G016 Institutional support: RVO:61388963 Keywords : density functional theory * interaction energies * halogen bonding Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.301, year: 2015

  7. Interface strength and degradation of adhesively bonded porous aluminum oxides

    NARCIS (Netherlands)

    Abrahami, S.T.; de Kok, John M.M.; Gudla, Visweswara C.; Ambat, Rajan; Terryn, H.A.; Mol, J.M.C.

    2017-01-01

    For more than six decades, chromic acid anodizing has been the main step in the surface treatment of aluminum for adhesively bonded aircraft structures. Soon this process, known for producing a readily adherent oxide with an excellent corrosion resistance, will be banned by strict international

  8. The effect of enamel bleaching on the shear bond strengths of metal and ceramic brackets.

    Science.gov (United States)

    Oztaş, E; Bağdelen, G; Kiliçoğlu, H; Ulukapi, H; Aydin, I

    2012-04-01

    The aim of this study was to evaluate the effects of bleaching and delayed bonding on the shear bond strengths of metal and ceramic brackets bonded with light and chemically cure composite resin to human enamel. One hundred and twenty extracted human premolar teeth were randomly divided into three groups of 40 each. The first two groups were bleached with 20 per cent carbamide peroxide (CP) at-home bleaching agent. No bleaching procedures were applied to the third group and served as control. The first two and control groups were divided into equal subgroups according to different adhesive-bracket combinations. Specimens in group 1 (n = 40) were bonded 24 hours after bleaching process was completed while the specimens in group 2 (n = 40) were bonded 14 days after. The specimens in all groups were debonded with a Universal testing machine while the modified adhesive remnant index was used to evaluate fracture properties. No statistically significant differences were found between the shear bond strengths of metal and ceramic brackets bonded to bleached enamel after 24 hours, 14 days, and unbleached enamel with light or chemical cure adhesives (P > 0.05). The mode of failure was mostly at the bracket/adhesive interface and cohesive failures within the resin were also observed. Our findings indicated that at-home bleaching agents that contain 20 per cent CP did not significantly affect the shear bond strength of metal and ceramic orthodontic brackets to enamel when bonding is performed 24 hours or 14 days after bleaching.

  9. Comparison of bonding strengths of the sapwoods and heartwoods ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-17

    Dec 17, 2008 ... strengths formed by joining the sapwood and heartwood of chestnut (Castanea sativa Mill.), oak ... nated by tar oil or epoxy resin to protect against damage .... phenol formaldehyde ... Preparation of experimental samples.

  10. In Vitro Evaluation of Shear Bond Strength of Self Etching Primers to Dentin

    Directory of Open Access Journals (Sweden)

    Reena Vora

    2012-01-01

    Full Text Available Objectives: To evaluate and compare the shear bond strength of four self etching primer adhesives to dentin. Materials & Methods: A total of 75 extracted human maxillary and mandibular molars were selected for the study. The teeth were divided into 5 groups of 15 teeth each, Group A- AdheSE (Ivoclar Vivadent, Group B-Adper prompt (3M ESPE, Group C- i bond (Heraeus-Kulzer, Group D-XenoIII (Dentsply, De Trey Group E-Single bond (3M ESPE was used and served as control. All the adhesives were applied according to the manufacturer′s instructions. Composite post was built on these bonded surfaces using Z-100 hybrid composite. The teeth were subjected to thermocycling for 500 cycles between 5°C to 55°C. The teeth were then mounted on universal testing machine and fractured under a shearing load, applied at a speed of 0.2mm/min. The readings were noted, tabulated and shear bond strength calculated in Mega Pascal (Mpa units. Results: There was significant difference in the mean shear bond strength of the four self etching primers, adhesives tested. Shear strength values were in the range of 16.57 to 21.73 Mpa. Xeno III gave the highest mean of shear bond strength whereas Adhe SE showed the lowest value of shear strength. Conclusion: Based on the results of the study, it can be concluded that contemporary self etching primer adhesives bond successfully to dentin. Moreover the bonding ability of Self Etching Systems seems to be comparable to the conventional Total Etch Systems.

  11. Ultrastructural Analysis and Long-term Evaluation of Composite-Zirconia Bond Strength.

    Science.gov (United States)

    Aboushelib, Moustafa N; Ragab, Hala; Arnaot, Mohamed

    2018-01-01

    To evaluate the influence of different aging techniques on zirconia-composite microtensile bond strength using different surface treatments over a 5-year follow-up period. Zirconia disks received three surface treatments: airborne-particle abrasion with 50-μm aluminum oxide particles, selective infiltration etching (SIE), or fusion sputtering (FS). The specimens were bonded to pre-aged composite disks using a composite cement containing phosphate monomers (Panavia F2.0). Bonded specimens were sectioned into microbars (1 x 1 x 6 mm) using a precision cutting machine, and all microbars received thermocycling (15,000 cycles between 5°C and 55°C). Initial microtensile bond strength was evaluated, and the test was repeated after storage in the following media for five years (artificial saliva, 20% ethanol, 5% NaOH, 4% acetic acid, and 5% phosphoric acid). The test was repeated every 12 months for 5 years. Scanning electron microscopic images were used to analyze the zirconia-composite interface. A repeated measures ANOVA and Bonferroni post-hoc tests were used to analyze the data (n = 20, α = 0.05). Significantly higher microtensile bond strength was observed for SIE compared to fusion sputtering and airborne particle abrasion. Five years of artificial aging resulted in significant reduction of zirconia-composite bond strength for all tested specimens. Zirconia-composite bond strength was more sensitive to storage in sodium hydroxide and phosphoric acid, while it was least affected when stored under saliva. These changes were related to the mechanism of ultra-structural interaction between surface treatment and adhesive, as deterioration of the hybrid layer (composite-infiltrated ceramic) was responsible for bond degeneration. Zirconia-composite bond strength was influenced by 5 years of artificial aging.

  12. Effect of Nd: YAG laser irradiation on surface properties and bond strength of zirconia ceramics.

    Science.gov (United States)

    Liu, Li; Liu, Suogang; Song, Xiaomeng; Zhu, Qingping; Zhang, Wei

    2015-02-01

    This study investigated the effect of neodymium-doped yttrium aluminum garnet (Nd: YAG) laser irradiation on surface properties and bond strength of zirconia ceramics. Specimens of zirconia ceramic pieces were divided into 11 groups according to surface treatments as follows: one control group (no treatment), one air abrasion group, and nine laser groups (Nd: YAG irradiation). The laser groups were divided by applying with different output power (1, 2, or 3 W) and irradiation time (30, 60, or 90 s). Following surface treatments, the morphological characteristics of ceramic pieces was observed, and the surface roughness was measured. All specimens were bonded to resin cement. After, stored in water for 24 h and additionally aged by thermocycling, the shear bond strength was measured. Dunnett's t test and one-way ANOVA were performed as the statistical analyses for the surface roughness and the shear bond strength, respectively, with α = .05. Rougher surface of the ceramics could be obtained by laser irradiation with higher output power (2 and 3 W). However, cracks and defects were also found on material surface. The shear bond strength of laser groups was not obviously increased, and it was significantly lower than that of air abrasion group. No significant differences of the shear bond strength were found among laser groups treated with different output power or irradiation time. Nd: YAG laser irradiation cannot improve the surface properties of zirconia ceramics and cannot increase the bond strength of the ceramics. Enhancing irradiation power and extending irradiation time cannot induce higher bond strength of the ceramics and may cause material defect.

  13. Sealing ability and bond strength of four contemporary adhesives to enamel and to dentine.

    Science.gov (United States)

    Atash, R; Vanden Abbeele, A

    2005-12-01

    To compare the shear bond strength and microleakage of four adhesive systems to the enamel and dentine of primary bovine teeth. 120 bovine primary mandibular incisors were collected and stored in an aqueous 1% chloramine solution at room temperature for no longer than 3 months after extraction (80 for shear bond testing and 40 for microleakage evaluation). The adhesives tested were Clearfil SE bond (SE), Adper Prompt L Pop (LP), Xeno III (XE), and Prime and Bond NT (PB). For shear bond strength testing the specimens were wet ground to 600 grit SiC paper to expose a flat enamel or dentine surface. After bonding and restoration with Dyract AP (DAP), the teeth were subjected to shear stress using a universal testing machine. For microleakage evaluation, facial class V cavities were prepared half in enamel and half in cementum. All cavities were restored with DAP. After thermocycling and immersion in 2% methylene blue, the dye penetration was evaluated under a stereomicroscope. All data were analysed by Chi-square tests or Fisher's tests when adapted in order to determine the significant differences between groups. Results were considered as significant for p enamel 11.06 to 5.34, in decreasing order SE, LP, XE and PB and on dentine 10.47 to 4.74, in decreasing order SE, XE, LP and PB. Differences in bond strengths between the four systems on enamel and dentine were all statistically significant, excepted for XE vs LP (shear bond at dentine). No significant differences were recorded in the microleakage degree between the four adhesive systems on enamel and on dentine (p > 0.0.5). The highest shear bond strength was achieved by Clearfil SE bond and the lowest by Prime and Bond NT. There was no significant difference concerning the sealing ability of the four adhesive systems.

  14. Comparative Evaluation of shear Bond Strength of universal Dental Adhesives -An in vitro study.

    Science.gov (United States)

    Jayasheel, Arun; Niranjan, Nandini; Pamidi, Hemanthkumar; Suryakanth, Mayuri B

    2017-07-01

    Patient demand for tooth colored restorations and desire for minimally invasive restorations have made composites an indispensable part of the restorative process. An important factor affecting the intra-oral performance of composite restorations is bonding. Ninty six freshly extracted molar teeth were collected and occlusal 3mm is removed using a diamond disc to expose dentine. Following with samples were divided in to two main groups (self-etch & total etch). Each main group is again sub divided in to three groups each according to bonding agent used (Tetric N- Bond Universal, Single Bond Universal, Tetric N Bond Total etch in total etch group and Clear Fill SE in self etch group). Following which bonding protocol is followed according to manufacture instructions, a composite buildup of 2x3 mm is done on each specimen and then specimen were subjected to shear bond test under universal testing machine. All the readings were noted and subjected to statistical analysis using One way ANOVA and Tukey's posthoc test. It showed that there is no significant difference among the groups in both self-etch and total etch modes. It can be concluded that application of an etching step prior to Universal Adhesives significantly improves their dentine penetration pattern, although this does not affect their mean SBS. The bond strength values of the TBU regardless of application mode were comparable to SBU making them reliable for working under different clinical conditions. Key words: Dentine bonding agents, self-etch mode, total etch mode, shear bond strength.

  15. Corrosion-induced bond strength degradation in reinforced concrete-Analytical and empirical models

    International Nuclear Information System (INIS)

    Bhargava, Kapilesh; Ghosh, A.K.; Mori, Yasuhiro; Ramanujam, S.

    2007-01-01

    The present paper aims to investigate the relationship between the bond strength and the reinforcement corrosion in reinforced concrete (RC). Analytical and empirical models are proposed for the bond strength of corroded reinforcing bars. Analytical model proposed by Cairns.and Abdullah [Cairns, J., Abdullah, R.B., 1996. Bond strength of black and epoxy-coated reinforcement-a theoretical approach. ACI Mater. J. 93 (4), 362-369] for splitting bond failure and later modified by Coronelli [Coronelli, D. 2002. Corrosion cracking and bond strength modeling for corroded bars in reinforced concrete. ACI Struct. J. 99 (3), 267-276] to consider the corroded bars, has been adopted. Estimation of the various parameters in the earlier analytical model has been proposed by the present authors. These parameters include corrosion pressure due to expansive action of corrosion products, modeling of tensile behaviour of cracked concrete and adhesion and friction coefficient between the corroded bar and cracked concrete. Simple empirical models are also proposed to evaluate the reduction in bond strength as a function of reinforcement corrosion in RC specimens. These empirical models are proposed by considering a wide range of published experimental investigations related to the bond degradation in RC specimens due to reinforcement corrosion. It has been found that the proposed analytical and empirical bond models are capable of providing the estimates of predicted bond strength of corroded reinforcement that are in reasonably good agreement with the experimentally observed values and with those of the other reported published data on analytical and empirical predictions. An attempt has also been made to evaluate the flexural strength of RC beams with corroded reinforcement failing in bond. It has also been found that the analytical predictions for the flexural strength of RC beams based on the proposed bond degradation models are in agreement with those of the experimentally

  16. Interface strength and degradation of adhesively bonded porous aluminum oxides

    DEFF Research Database (Denmark)

    T. Abrahami, Shoshan; M. M. de Kok, John; Gudla, Visweswara Chakravarthy

    2017-01-01

    For more than six decades, chromic acid anodizing has been the main step in the surface treatment of aluminum for adhesivelybonded aircraft structures. Soon this process, known for producing a readily adherent oxide with an excellent corrosion resistance,will be banned by strict international....... The relationship between the anodizing conditions insulfuric and mixtures of sulfuric and phosphoric acid electrolytes and the formation and durability of bonding under variousenvironmental conditions was investigated. Scanning electron microscopy was used to characterize the oxide features. Selectedspecimens were...... studied with transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy to measureresin concentration within structurally different porous anodic oxide layers as a function of depth. Results show that there are twocritical morphological aspects for strong and durable bonding. First...

  17. Protein Modifiers Generally Provide Limited Improvement in Wood Bond Strength of Soy Flour Adhesives

    Science.gov (United States)

    Charles R. Frihart; Linda Lorenz

    2013-01-01

    Soy flour adhesives using a polyamidoamine-epichlorohydrin (PAE) polymeric coreactant are used increasingly as wood adhesives for interior products. Although these adhesives give good performance, higher bond strength under wet conditions is desirable. Wet strength is important for accelerated tests involving the internal forces generated by the swelling of wood and...

  18. Microshear bond strength of resin composite to teeth affected by molar hypomineralization using 2 adhesive systems.

    Science.gov (United States)

    William, Vanessa; Burrow, Michael F; Palamara, Joseph E A; Messer, Louise B

    2006-01-01

    When restoring hypomineralized first permanent molars, placement of cavo-surface margins can be difficult to ascertain due to uncertainty of the bonding capability of the tooth surface. The purpose of this study was to investigate the adhesion of resin composite bonded to control and hypomineralized enamel with an all-etch single-bottle adhesive or self-etching primer adhesive. Specimens of control enamel (N=44) and hypomineralized enamel (N=45) had a 0.975-mm diameter composite rod (Filtek Supreme Universal Restorative) bonded with either 3M ESPE Single Bond or Clearfil SE Bond following manufacturers' instructions. Specimens were stressed in shear at 1 mm/min to failure (microshear bond strength). Etched enamel surfaces and enamel-adhesive interfaces were examined under scanning electron microscopy. The microshear bond strength (MPa) of resin composite bonded to hypomineralized enamel was significantly lower than for control enamel (3M ESPE Single Bond=7.08 +/- 4.90 vs 16.27 +/- 10.04; Clearfil SE Bond=10.39 +/- 7.56 vs 19.63 +/- 7.42; P=.001). Fractures were predominantly adhesive in control enamel and cohesive in hypomineralized enamel. Scotchbond etchant produced deep interprismatic and intercrystal porosity in control enamel and shallow etch patterns with minimal intercrystal porosity in hypomineralized enamel. Control enamel appeared almost unaffected by SE Primer; hypomineralized enamel showed shallow etching. The hypomineralized enamel-adhesive interface was porous with cracks in the enamel. The control enamel-adhesive interface displayed a hybrid layer of even thickness. The microshear bond strength of resin composite bonded to hypomineralized enamel was significantly lower than for control enamel. This was supported by differences seen in etch patterns and at the enamel-adhesive interface.

  19. Effect of universal adhesive etching modes on bond strength to dual-polymerizing composite resins.

    Science.gov (United States)

    Michaud, Pierre-Luc; Brown, Matthew

    2018-04-01

    Information is lacking as to the effect on bond strength of the etching modes of universal adhesives when they are used to bond dual-polymerizing composite resins to dentin. The purpose of this in vitro study was to investigate the bonding of dual-polymerizing foundation composite resins to dentin when universal bonding agents are used in self-etch or etch-and-rinse modes. Sixty caries-free, extracted third molar teeth were sectioned transversely in the apical third of the crown and allocated to 12 groups (n=5). Three different bonding agents (Scotchbond Universal, OptiBond XTR, All-Bond Universal) were used to bond 2 different dual-polymerizing composite resins (CompCore AF or CoreFlo DC) to dentin, using 2 different etching approaches (etch-and-rinse or self-etch). The specimens were sectioned into sticks (1×1×8 mm) with a precision saw. The bond strength of the specimens was tested under microtensile force at a crosshead speed of 0.5 mm/min. The data were analyzed using a 3-way ANOVA, a Games-Howell post hoc comparisons model, and Student t tests with Bonferroni corrections (α=.05). In the overall model, the composite resin used had no effect on bond strength (P=.830). The etching protocol by itself also did not have a significant effect (P=.059), although a trend was present. The bonding agent, however, did have an effect (Pcomposite resins to dentin, no single etching protocol is better than another. Depending on which bonding agent is being used, one etching mode may perform better. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  20. Correlation among electronegativity, cation polarizability, optical basicity and single bond strength of simple oxides

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrov, Vesselin, E-mail: vesselin@uctm.edu [Department of Silicate Technology, University of Chemical Technology and Metallurgy, 8, Kl. Ohridski Blvd., Sofia 1756 (Bulgaria); Komatsu, Takayuki, E-mail: komatsu@mst.nagaokaut.ac.jp [Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka-cho, Nagaoka 940-2188 (Japan)

    2012-12-15

    A suitable relationship between free-cation polarizability and electronegativity of elements in different valence states and with the most common coordination numbers has been searched on the basis of the similarity in physical nature of both quantities. In general, the cation polarizability increases with decreasing element electronegativity. A systematic periodic change in the polarizability against the electronegativity has been observed in the isoelectronic series. It has been found that generally the optical basicity increases and the single bond strength of simple oxides decreases with decreasing the electronegativity. The observed trends have been discussed on the basis of electron donation ability of the oxide ions and type of chemical bonding in simple oxides. - Graphical abstract: This figure shows the single bond strength of simple oxides as a function of element electronegativity. A remarkable correlation exists between these independently obtained quantities. High values of electronegativity correspond to high values of single bond strength and vice versa. It is obvious that the observed trend in this figure is closely related to the type of chemical bonding in corresponding oxide. Highlights: Black-Right-Pointing-Pointer A suitable relationship between free-cation polarizability and electronegativity of elements was searched. Black-Right-Pointing-Pointer The cation polarizability increases with decreasing element electronegativity. Black-Right-Pointing-Pointer The single bond strength of simple oxides decreases with decreasing the electronegativity. Black-Right-Pointing-Pointer The observed trends were discussed on the basis of type of chemical bonding in simple oxides.

  1. In vitro analysis of shear bond strength and adhesive remnant index of different metal brackets

    Directory of Open Access Journals (Sweden)

    Fernanda de Souza Henkin

    Full Text Available ABSTRACT Introduction: There is a great variety of orthodontic brackets in the Brazilian market, and constantly evaluating them is critical for professionals to know their properties, so as to be able to choose which product best suits their clinical practice. Objectives: To evaluate the bond strength and the adhesive remnant index (ARI of different brands of metal brackets. Material and Methods: A total of 105 bovine incisors were used, and brackets of different brands were bonded to teeth. Seven different bracket brands were tested (MorelliTM, American OrthodonticsTM, TP OrthodonticsTM, Abzil-3MTM, OrthometricTM, TecnidentTM and UNIDENTM. Twenty-four hours after bonding, shear bond strength test was performed; and after debonding, the ARI was determined by using an optical microscope at a 10-fold increase. Results: Mean shear bond strength values ranged from 3.845 ± 3.997 (MorelliTM to 9.871 ± 5.106 MPa (TecnidentTM. The majority of the ARI index scores was 0 and 1. Conclusion: Among the evaluated brackets, the one with the lowest mean shear bond strength values was MorelliTM. General evaluation of groups indicated that a greater number of bond failure occurred at the enamel/adhesive interface.

  2. Effect of glutaraldehyde and ferric sulfate on shear bond strength of adhesives to primary dentin

    Directory of Open Access Journals (Sweden)

    Prabhakar A

    2008-12-01

    Full Text Available Aim: The present study was undertaken to evaluate the effect of alternative pulpotomy agents such as glutaraldehyde and ferric sulfate on the shear bond strength of self-etch adhesive systems to dentin of primary teeth. Materials and Methods: Eighty human primary molar teeth were sectioned in a mesiodistal direction and divided into experimental and control groups. Lingual dentin specimens in experimental groups were treated with glutaraldehyde and ferric sulfate. Buccal surfaces soaked in water served as control group. Each group was then divided into two groups based on the adhesive system used: Clearfil SE Bond and Adper Prompt L-Pop. A teflon mold was used to build the composite (Filtek Z-250 cylinders on the dentinal surface of all the specimens. Shear bond strength was tested for all the specimens with an Instron Universal Testing Machine. The failure mode analysis was performed with a Scanning Electron Microscope (SEM. Results: The results revealed that glutaraldehyde and ferric sulfate significantly reduced the shear bond strength of the tested adhesive systems to primary dentin. Clearfil SE Bond showed much higher shear bond strength than Adper Prompt L Pop to primary dentin. SEM analysis revealed a predominant cohesive failure mode for both adhesive systems. Conclusion: This study revealed that the pulpotomy medicaments glutaraldehyde and ferric sulfate adversely affected the bonding of self-etch adhesive systems to primary dentin.

  3. In vitro analysis of shear bond strength and adhesive remnant index of different metal brackets

    Science.gov (United States)

    Henkin, Fernanda de Souza; de Macêdo, Érika de Oliveira Dias; Santos, Karoline da Silva; Schwarzbach, Marília; Samuel, Susana Maria Werner; Mundstock, Karina Santos

    2016-01-01

    ABSTRACT Introduction: There is a great variety of orthodontic brackets in the Brazilian market, and constantly evaluating them is critical for professionals to know their properties, so as to be able to choose which product best suits their clinical practice. Objectives: To evaluate the bond strength and the adhesive remnant index (ARI) of different brands of metal brackets. Material and Methods: A total of 105 bovine incisors were used, and brackets of different brands were bonded to teeth. Seven different bracket brands were tested (MorelliTM, American OrthodonticsTM, TP OrthodonticsTM, Abzil-3MTM, OrthometricTM, TecnidentTM and UNIDENTM). Twenty-four hours after bonding, shear bond strength test was performed; and after debonding, the ARI was determined by using an optical microscope at a 10-fold increase. Results: Mean shear bond strength values ranged from 3.845 ± 3.997 (MorelliTM) to 9.871 ± 5.106 MPa (TecnidentTM). The majority of the ARI index scores was 0 and 1. Conclusion: Among the evaluated brackets, the one with the lowest mean shear bond strength values was MorelliTM. General evaluation of groups indicated that a greater number of bond failure occurred at the enamel/adhesive interface. PMID:28125142

  4. [Effects of magnetron sputtered ZrN on the bonding strength of titanium porcelain].

    Science.gov (United States)

    Zhou, Shu; Zhang, Wen-yan; Guang, Han-bing; Xia, Yang; Zhang, Fei-min

    2009-04-01

    To investigate the effect of magnetron sputtered ZrN on the bonding strength between a low-fusing porcelain (Ti/Vita titankeramik system) and commercially pure cast titanium. Sixteen specimens were randomly assigned to test group and control group (n=8). The control group received no surface treated. Magnetron sputtered ZrN film was deposited on the surface of specimens in the test group. Then the sixteen titanium-porcelain specimens were prepared in a rectangular shape and went through three-point bending test on a universal test machine. The bond strength of Ti/porcelain was recorded. The phase composition of the specimens was analyzed using X-ray diffraction (XRD). The interface at titanium and porcelain and the titanium surface after debonding were observed with a scanning electron microscopy (SEM) and analyzed using energy depressive spectrum (EDS). New phase of ZrN was found with XRD in the test group. Statistical analysis showed higher bond strength following ZrN surface treatment in the test group [(45.991+/-0.648) MPa] than that in the control group [(29.483+/-1.007) MPa] (P=0.000). Bonded ceramic could be observed in test group, the amount of bonded ceramic was more than that in the control group. No obvious bonded ceramic in control group was found. Magnetron sputtered ZrN can improve bond strength of Ti/Vita titankeramik system significantly.

  5. Problems in Standardization of Orthodontic Shear Bond Strength Tests; A Brief Review

    Directory of Open Access Journals (Sweden)

    M.S. A. Akhoundi

    2005-03-01

    Full Text Available Bonding brackets to the enamel surface has gained much popularity today. New adhesive systems have been introduced and marketed and a considerable increase in research regarding bond strength has been published. A considerable amount of these studies deal with shear bond strength of adhesives designed for orthodontic purpose.Previous studies have used variety of test designs. This diversity in test design is due to the fact that there is no standard method for evaluating shear bond strength in orthodontics. Therefore comparison of data obtained from different study is almost impossible.This article tries to briefly discuss the developments occurred in the process of shear bond strength measurement of orthodontic adhesives with an emphasis on the type of test set up and load application.Although the test designs for measuring shear bond strength in orthodontics are still far from ideal, attempts must be made to standardize these tests especially in order to makecomparison of different data easier. It is recommended that test designs be set up in such a manner that better matches with the purpose of the study.

  6. Effect of blood contamination on shear bond strength of orthodontic brackets and disinclusion buttons.

    Science.gov (United States)

    Sfondrini, Maria Francesca; Gatti, Sara; Scribante, Andrea

    2011-07-01

    Our aim was to assess the effect of blood contamination on the shear bonding strength and sites of failure of orthodontic brackets and bondable buttons. We randomly divided 160 bovine permanent mandibular incisors into 8 groups of 20 specimens each. Both orthodontic brackets (Step brackets, Leone, Sesto Fiorentino, Italy) and bondable buttons (Flat orthodontic buttons, Leone, Sesto Fiorentino, Italy) were tested on four different enamel surfaces: dry; contamination with blood before priming; after priming; and before and after priming. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bonding strength and the rate of adhesive failures were recorded. Data were analysed using the analysis of variance (ANOVA), Scheffè tests, and the chi-square test. Uncontaminated enamel surfaces showed the highest bonding strengths for both brackets and buttons. When they were contaminated with blood, orthodontic brackets had significantly lower shear strengths than bondable buttons (P=0.0001). There were significant differences in sites of failure among the groups for the various enamel surfaces (P=0.001). Contamination of enamel by blood during bonding lowers the strength of the bond, more so with orthodontic brackets than with bondable buttons. Copyright © 2010 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. Influence of previous acid etching on bond strength of universal adhesives to enamel and dentin.

    Science.gov (United States)

    Torres, Carlos Rocha Gomes; Zanatta, Rayssa Ferreira; Silva, Tatiane Josefa; Huhtala, Maria Filomena Rocha Lima; Borges, Alessandra Bühler

    2017-01-01

    The objective of this study was to evaluate the effect of acid pretreatment on the bond strength of composite resin bonded to enamel and dentin with 2 different universal self-etching adhesives. The null hypothesis was that the acid treatment performed prior to adhesive application would not significantly change the bond strength to enamel or dentin for either universal adhesive tested. A sample of 112 bovine incisors were selected and embedded in acrylic resin. Half were ground until a flat enamel surface was obtained, and the other half were polished until a 6 × 6-mm area of dentin was exposed, resulting into 2 groups (n = 56). The enamel and dentin groups were divided into 2 subgroups according to the adhesive system applied: Futurabond U or Scotchbond Universal. Each of these subgroups was divided into 2 additional subgroups (n = 14); 1 subgroup received phosphoric acid pretreatment, and 1 subgroup did not. The bond strength was assessed with a microtensile test. Data from enamel and dentin specimens were analyzed separately using 1-way analysis of variance. The acid pretreatment did not significantly change the bond strength of the adhesives tested, either to enamel (P = 0.4161) or to dentin (P = 0.4857). The acid etching pretreatment did not affect the bond strength to dentin and enamel when the tested universal multipurpose adhesive systems were used.

  8. Effect of Quaternary Ammonium Salt on Shear Bond Strength of Orthodontic Brackets to Enamel

    Directory of Open Access Journals (Sweden)

    Hannaneh Ghadirian

    2017-10-01

    Full Text Available Objectives: This study sought to assess the effect of quaternary ammonium salt (QAS on shear bond strength of orthodontic brackets to enamel.Materials and Methods: In this in vitro experimental study, 0, 10, 20 and 30% concentrations of QAS were added to Transbond XT primer. Brackets were bonded to 60 premolar teeth using the afore-mentioned adhesive mixtures, and the shear bond strength of the four groups (n=15 was measured using a universal testing machine. After debonding, the adhesive remnant index (ARI score was determined under a stereomicroscope. Data were analyzed using one-way ANOVA.Results: The mean and standard deviation of shear bond strength of the control and 10%, 20% and 30% groups were 23.54±6.31, 21.81±2.82, 20.83±8.35 and 22.91±5.66 MPa, respectively. No significant difference was noted in shear bond strength of the groups (P=0.83. Study groups were not different in terms of ARI scores (P=0.80.Conclusions: The results showed that addition of QAS to Transbond XT primer had no adverse effect on shear bond strength of orthodontic brackets.

  9. Evaluation of bond strength of isothermally aged plasma sprayed thermal barrier coating

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Jin; Lee, Dong Hoon; Koo, Jae Mean; Song, Sung Jin; Seok, Chang Sung [Sungkyunkwan University, Suwon (Korea, Republic of); Kim, Mun Young [Korea Plant Service and Engineering Co., Ltd., Seongnam (Korea, Republic of)

    2008-07-15

    In this study, disk type of thermal barrier coating system for gas turbine blade was isothermally aged in the furnace changing exposure time and temperature. For each aging condition, bond tests for three samples were conducted for evaluating degradation of adhesive or cohesive strength of thermal barrier coating system. For as-sprayed condition, the location of fracture in the bond test was in the middle of epoxy which have bond strength of 57 MPa. As specimens are degraded by thermal aging, bond strength gradually decreased and the location of failure was also changed from within top coat at the earlier stage of thermal aging to the interface between top coat and TGO at the later stage due to the delamination in the coating.

  10. Microtensile bond strength of composite resin to human enamel prepared using erbium: Yttrium aluminum garnet laser.

    Science.gov (United States)

    Delfino, Carina Sinclér; Souza-Zaroni, Wanessa Christine; Corona, Silmara Aparecida Milori; Palma-Dibb, Regina Guenka

    2007-02-01

    The Erbium: Yttrium Aluminum Garnet (YAG) laser used for preparation of cavity can alter the substrate and it could influence the bond strength of enamel. The aim of this in vitro study was to evaluate the influence of Er:YAG laser's energy using microtensile bond test. Three groups were obtained (cavity preparation) and each group was divided into two subgroups (adhesive system). After that the adhesive protocol was performed, sections with a cross-sectional area of 0.8 mm2 (+/-0.2 mm2) were obtained. The specimens were mounted in a universal testing machine (0.5 mm/min). Statistical analysis showed a decrease in bond strength for lased groups (p adhesive system was used the laser 300 mJ subgroup showed higher bond strength compared to the laser 250 mJ (p adhesive procedures than conventional bur-cut cavities. Copyright 2006 Wiley Periodicals, Inc.

  11. Effect of saliva decontamination procedures on shear bond strength of a one-step adhesive system.

    Science.gov (United States)

    Ülker, E; Bilgin, S; Kahvecioğlu, F; Erkan, A I

    2017-09-01

    To evaluate the effect of different saliva decontamination procedures on the shear bond strength of a one-step universal adhesive system (Single Bond™ Universal Adhesive, 3M ESPE, St. Paul, MN, USA). The occlusal surfaces of 75 human third molars were ground to expose dentin. The teeth were divided into the following groups: Group 1 (control group): Single Bond™ Universal Adhesive was applied to the prepared tooth according to the manufacturer's recommendations and light cured; no contamination procedure was performed. Group 2: Bonding, light curing, saliva contamination, and dry. Group 3: Bonding, light curing, saliva contamination, rinse, and dry. Group 4: After the procedure performed in Group 2, reapplication of bonding. Group 5: After the procedure performed in Group 3, reapplication of bonding. Then, composite resins were applied with cylindrical-shaped plastic matrixes and light cured. For shear bond testing, a notch-shaped force transducer apparatus was applied to each specimen at the interface between the tooth and composite until failure occurred. The data were statistically analyzed using one-way ANOVA. One-way ANOVA revealed significant differences in shear bond strength between the control group and experimental Groups 2 and 4 (P 0.05). The present in vitro study showed that water rinsing is necessary if cured adhesive resin is contaminated with saliva to ensure adequate bond strength.

  12. Adhesive bond strength evaluation in composite materials by laser-generated high amplitude ultrasound

    International Nuclear Information System (INIS)

    Perton, M; Blouin, A; Monchalin, J-P

    2011-01-01

    Adhesive bonding of composites laminates is highly efficient but is not used for joining primary aircraft structures, since there is presently no nondestructive inspection technique to ensure the quality of the bond. We are developing a technique based on the propagation of high amplitude ultrasonic waves to evaluate the adhesive bond strength. Large amplitude compression waves are generated by a short pulse powerful laser under water confinement and are converted after reflection by the assembly back surface into tensile waves. The resulting tensile stresses can cause a delamination inside the laminates or at the bond interfaces. The adhesion strength is evaluated by increasing the laser pulse energy until disbond. A good bond is unaffected by a certain level of stress whereas a weaker one is damaged. The method is shown completely non invasive throughout the whole composite assembly. The sample back surface velocity is measured by an optical interferometer and used to estimate stress history inside the sample. The depth and size of the disbonds are revealed by a post-test inspection by the well established laser-ultrasonic technique. Experimental results show that the proposed method is able to differentiate weak bond from strong bonds and to estimate quantitatively their bond strength.

  13. Factors Affecting the Shear Bond Strength of Orthodontic Brackets - a Review of In Vitro Studies.

    Science.gov (United States)

    Bakhadher, Waleed; Halawany, Hassan; Talic, Nabeel; Abraham, Nimmi; Jacob, Vimal

    2015-01-01

    The adhesive material used to bond orthodontic brackets to teeth should neither fail during the treatment period, resulting in treatment delays, untoward expenses or patient inconvenience nor should it damage the enamel on debonding at the end of the treatment. Although the effectiveness of a bonding system and any unfavorable effects on the enamel may be studied by conducting in-vivo studies, it is nearly impossible to independently analyze different variables that influence a specific bonding system in the oral environment. In-vitro studies, on the other hand, may utilize more standardized protocols for testing different bonding systems and materials available. Thus, the present review focused attention on in-vitro studies and made an attempt to discuss material-related, teeth-related (fluorotic vs non-fluorotic teeth) and other miscellaneous factors that influences the shear bond strength of orthodontic brackets. Within the limitations of this review, using conventional acid-etch technique, ceramic brackets and bonding to non-fluorotic teeth was reported to have a positive influence on the shear bond strength of orthodontic brackets, but higher shear bond strength found on using ceramic brackets can be dangerous for the enamel.

  14. Effects of endodontic tri-antibiotic paste on bond strengths of dentin adhesives to coronal dentin

    Directory of Open Access Journals (Sweden)

    Parvin Mirzakoucheki

    2015-05-01

    Full Text Available Objectives The aim of this study was to evaluate the effects of tri-antibiotic paste (TAP on microtensile bond strengths (MTBS of dental adhesives to dentin. Materials and Methods Sixty extracted molars had their occlusal surfaces flattened to expose dentin. They were divided into two groups, i.e., control group with no dentin treatment and experimental group with dentin treatment with TAP. After 10 days, specimens were bonded using self-etch (Filtek P90 adhesive or etch-and-rinse (Adper Single Bond Plus adhesives and restored with composite resin. Teeth were sectioned into beams, and the specimens were subjected to MTBS test. Data were analyzed using two-way ANOVA and post hoc Tukey tests. Results There was a statistically significant interaction between dentin treatment and adhesive on MTBS to coronal dentin (p = 0.003. Despite a trend towards worse MTBS being noticed in the experimental groups, TAP application showed no significant effect on MTBS (p = 0.064. Conclusions The etch-and-rinse adhesive Adper Single Bond Plus presented higher mean bond strengths than the self-etch adhesive Filtek P90, irrespective of the group. The superior bond performance for Adper Single Bond when compared to Filtek P90 adhesive was confirmed by a fewer number of adhesive failures. The influence of TAP in bond strength is insignificant.

  15. Microshear bond strength of composite resins to enamel and porcelain substrates utilizing unfilled versus filled resins.

    Science.gov (United States)

    Najafi-Abrandabadi, Ahmad; Najafi-Abrandabadi, Siamak; Ghasemi, Amir; Kotick, Philip G

    2014-11-01

    Failures such as marginal discoloration and composite chipping are still the problems of tooth-colored restorations on the substrate of enamel and porcelain, which some of these problems are consequently as a result of failures in the bonding layer. Using filled resin has been recently introduced to increase the bond strength of this layer. The aim of this study was to compare the microshear bond strength (μ-SBS) of composite resins to enamel incubated in periods of 24 h and 9 months and porcelain with unfilled resin and flowable composites (filled resin). In this in vitro study, two groups of 75 enamel samples with different storage times (24 h and 9 months) and a group of 75 porcelain samples were used. They were divided into 5 experimental groups of 15 samples in each. Composite cylinders in tygon tubes were bonded on the surface of acid-etched enamel and pretreated porcelain. Wave, Wave MV, Wave HV, Grandioflow and Margin Bond were used as bonding agents. The μ-SBS was measured at the speed of 1.0 mm/min. The bond strengths were analyzed with one-way analysis of variance (ANOVA) test followed by Tukey test. P composites (filled resins) can be used instead of unfilled resins in bonding composite resins to enamel and porcelain substrates.

  16. Long-term Bond Strength between Layering Indirect Composite Material and Zirconia Coated with Silicabased Ceramics.

    Science.gov (United States)

    Fushiki, Ryosuke; Komine, Futoshi; Honda, Junichi; Kamio, Shingo; Blatz, Markus B; Matsumura, Hideo

    2015-06-01

    This study evaluated the long-term shear bond strength between an indirect composite material and a zirconia framework coated with silica-based ceramics, taking the effect of different primers into account. A total of 165 airborne-particle abraded zirconia disks were subjected to one of three pretreatments: no pretreatment (ZR-AB), airborne-particle abrasion of zirconia coated with feldspathic porcelain (ZR-PO-AB), and 9.5% hydrofluoric acid etching of zirconia coated with feldspathic porcelain (ZR-PO-HF). An indirect composite material (Estenia C&B) was then bonded to the zirconia disks after they were treated with one of the following primers: Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + Activator), Estenia Opaque Primer (EOP), Porcelain Liner M Liquid B (PLB), or no priming (CON, control group). Shear bond strength was tested after 100,000 thermocycles, and the data were analyzed using the Steel-Dwass U-test (α = 0.05). For ZR-PO-AB and ZR-PO-HF specimens, bond strength was highest in the CPB+Activator group (25.8 MPa and 22.4 MPa, respectively). Bond strengths were significantly lower for ZR-AB specimens in the CON and PLB groups and for ZR-PO-AB specimens in the CON, CPB, and EOP groups. Combined application of a hydrophobic phosphate monomer (MDP) and silane coupling agent enhanced the long-term bond strength of indirect composite material to a zirconia coated with silica-based ceramics.

  17. Strength and water absorption characteristics of cement-bonded ...

    African Journals Online (AJOL)

    Contrary to conventional practice, the boards were fabricated in the laboratory without external pressure application. The effects of calcium chloride (CaCl2) addition on the hardening time, appearance, bending and compressive strength, and water absorption properties of the boards were also investigated. The boards had ...

  18. Shear strength of orthodontic bracket bonding with GIC bonding agent after the application of CPP-ACPF paste

    Directory of Open Access Journals (Sweden)

    Melisa Budipramana

    2013-03-01

    Full Text Available Background: White spot lesion is a major problem during fixed orthodontic treatment. This problem can be solved by minimizing white spot lesion before the treatment and using a fluoride-releasing bonding agent. The application of casein phosphopeptidesamorphous calcium phospate fluoride (CPP-ACPF paste as remineralization agent before treatment and GIC as orthodontic bonding agent is expected to overcome this problem as well as to strengthen GIC bonding. Purpose: To measure the shear strength of fix orthodontic appliance using GIC bonding with CPP-ACPF application prior treatment. Methods: In this study, 50 extracted premolars were randomly divided into 2 groups: group 1 as treatment group and group II as control group that was not given CPPACPF pretreatment. After having been cut and put into acrylic device, the samples in group I were given pretreatment with CPP-ACPF paste on enamel surface for 2 minutes twice a day as instructed in product label for 14 days. Orthodontic brackets were bonded with GIC bonding agent on all samples in both groups as instructed in product label. Then, the shear strength was measured by Autograph Shimatzu with crosshead speed 0.5 mm/minute. The data was analyzed with Independent t-test. Results: The mean shear bond strength in treatment group was 19.22 ± 4.04 MPa and in control group was 12.97 ± 3.97 MPa. Independent t-test analysis showed that there was a significant difference between treatment and control group (p<0.05. Conclusion: CPP-ACPF pretreatment could increase GIC orthodontic bonding shear strength.Latar belakang: Lesi putih karies merupakan masalah utama selama perawatan dengan peranti cekat ortodonti. Hal ini dapat diatasi dengan cara mengurangi lesi putih sebelum perawatan dengan menggunakan bahan bonding yang mengandung fluorida. Aplikasi pasta casein phosphopeptides-amorphous calcium phospate fluoride (CPP-ACPF sebagai bahan remineralisasi sebelum perawatan dan bahan bonding GIC diharapkan dapat

  19. Effects of silane application on the shear bond strength of ceramic orthodontic brackets to enamel surface

    Directory of Open Access Journals (Sweden)

    Pinandi Sri Pudyani

    2016-12-01

    Full Text Available Background: Fixed orthodontic appliances with ceramic brackets are used frequently to fulfill the aesthetic demand of patient through orthodontic treatment. Ceramic brackets have some weaknesses such as bond strength and enamel surface damage. In high bond strength the risk of damage in enamel surfaces increases after debonding. Purpose: This study aimed to determine the effect of silane on base of bracket and adhesive to shear bond strength and enamel structure of ceramic bracket. Method: Sixteen extracted upper premolars were randomly divided into four groups based on silane or no silane on the bracket base and on the adhesive surface. Design of the base on ceramic bracket in this research was microcrystalline to manage the influence of mechanical interlocking. Samples were tested in shear mode on a universal testing machine after attachment. Following it, adhesive remnant index (ARI scores were used to assess bond failure site. Statistical analysis was performed using a two-way Anova and the Mann-Whitney test. A scanning electron microscope (SEM with a magnification of 2000x was used to observe enamel structure after debonding. Result: Shear bond strength was increased between group without silane and group with silane on the base of bracket (p<0,05. There was no significance different between group without silane and group with silane on adhesive (p<0,05. Conclusion: Application of silane on base of bracket increases shear bond strength, however, application of silane on adhesive site does not increase shear bond strength of ceramic bracket. Most bonding failure occurred at the enamel adhesive interface and damage occurred on enamel structure in group contains silane of ceramic bracket.

  20. Microtensile bond strength of bulk-fill restorative composites to dentin.

    Science.gov (United States)

    Mandava, Jyothi; Vegesna, Divya-Prasanna; Ravi, Ravichandra; Boddeda, Mohan-Rao; Uppalapati, Lakshman-Varma; Ghazanfaruddin, M D

    2017-08-01

    To facilitate the easier placement of direct resin composite in deeper cavities, bulk fill composites have been introduced. The Mechanical stability of fillings in stress bearing areas restored with bulk-fill resin composites is still open to question, since long term clinical studies are not available so far. Thus, the objective of the study was to evaluate and compare the microtensile bond strength of three bulk-fill restorative composites with a nanohybrid composite. Class I cavities were prepared on sixty extracted mandibular molars. Teeth were divided into 4 groups (n= 15 each) and in group I, the prepared cavities were restored with nanohybrid (Filtek Z250 XT) restorative composite in an incremental manner. In group II, III and IV, the bulk-fill composites (Filtek, Tetric EvoCeram, X-tra fil bulk-fill restoratives) were placed as a 4 mm single increment and light cured. The restored teeth were subjected to thermocycling and bond strength testing was done using instron testing machine. The mode of failure was assessed by scanning electron microscope (SEM). The bond strength values obtained in megapascals (MPa) were subjected to statistical analysis, using SPSS/PC version 20 software.One-way ANOVA was used for groupwise comparison of the bond strength. Tukey's Post Hoc test was used for pairwise comparisons among the groups. The highest mean bond strength was achieved with Filtek bulk-fill restorative showing statistically significant difference with Tetric EvoCeram bulk-fill ( p composites. Adhesive failures are mostly observed with X-tra fil bulk fill composites, whereas mixed failures are more common with other bulk fill composites. Bulk-fill composites exhibited adequate bond strength to dentin and can be considered as restorative material of choice in posterior stress bearing areas. Key words: Bond strength, Bulk-fill restoratives, Configuration factor, Polymerization shrinkage.

  1. New endodontic obturation systems and their interfacial bond strength with intraradicular dentine - ex vivo studies.

    Science.gov (United States)

    Pawińska, M; Kierklo, A; Tokajuk, G; Sidun, J

    2011-01-01

    To comparatively evaluate adhesive properties of selected root canal fillings through the measurement of the material-dentine interfacial bond strength. Fifty extracted single-rooted human teeth with one canal each were prepared using Hero instruments to size 30.04. Teeth were divided into four subgroups depending on the root canal filling material and the method of obturation: Resilon/Epiphany - a thermoplastic method (IA), Resilon/Epiphany - a matching single-point method (IB), gutta-percha/Roeko Seal Automix - a thermoplastic method (IIA) and gutta-percha/Roeko Seal Automix - a matching single-point method (IIB). The obturated roots were cut perpendicular to the long axis to create 1.7 mm thick slices. The bond strength was measured for each test slice with push -out testing machine. The highest push-out bond strength was registered in subgroup IB (3.98 ± 1.33 MPa). Significantly lower bond strength was observed in subgroups IA (0.50 ± 0.24 MPa), IIA (0.33 ± 0.18 MPa) and IIB (0.08 ± 0.03 MPa) (pmaterial-dentine interfacial bond strength values were observed between IA and IIA, IA and IIB, IIA and IIB subgroups (p > 0.05). The push-out bond strength of the material-dentine interface was dependent on the type of material used and the root canal filling technique. The R/E system exhibited better adhesion ability to intraradicular dentine than G/RSA. The highest bond strength was observed for Resilon/Epiphany introduced with the single-cone technique.

  2. Effect of raw material ratios on the compressive strength of magnesium potassium phosphate chemically bonded ceramics

    International Nuclear Information System (INIS)

    Wang, Ai-juan; Yuan, Zhi-long; Zhang, Jiao; Liu, Lin-tao; Li, Jun-ming; Liu, Zheng

    2013-01-01

    The compressive strength of magnesium potassium phosphate chemically bonded ceramics is important in biomedical field. In this work, the compressive strength of magnesium potassium phosphate chemically bonded ceramics was investigated with different liquid-to-solid and MgO-to-KH 2 PO 4 ratios. X-ray diffractometer was applied to characterize its phase composition. The microstructure was imaged using a scanning electron microscope. The results showed that the compressive strength of the chemically bonded ceramics increased with the decrease of liquid-to-solid ratio due to the change of the packing density and the crystallinity of hydrated product. However, with the increase of MgO-to-KH 2 PO 4 weight ratio, its compressive strength increased firstly and then decreased. The low compressive strength in lower MgO-to-KH 2 PO 4 ratio might be explained by the existence of the weak phase KH 2 PO 4 . However, the low value of compressive strength with the higher MgO-to-KH 2 PO 4 ratio might be caused by lack of the joined phase in the hydrated product. Besides, it has been found that the microstructures were different in these two cases by the scanning electron microscope. Colloidal structure appeared for the samples with lower liquid-to-solid and higher MgO-to-KH 2 PO 4 ratios possibly because of the existence of amorphous hydrated products. The optimization of both liquid-to-solid and MgO-to-KH 2 PO 4 ratios was important to improve the compressive strength of magnesium potassium phosphate chemically bonded ceramics. - Highlights: • High packing density and amorphous hydrated phase improved the compressive strength. • Residual KH 2 PO 4 and poor bonding phase lower the compressive strength. • MPCBC fabricated with optimized parameters had the highest compressive strength

  3. Effect of nanotechnology in self-etch bonding systems on the shear bond strength of stainless steel orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Shaza M. Hammad

    Full Text Available ABSTRACT Objective: To evaluate the effect of silica dioxide (SiO2 nanofillers in different bonding systems on shear bond strength (SBS and mode of failure of orthodontic brackets at two experimental times. Methods: Ninety-six intact premolars were divided into four groups: A Conventional acid-etch and primer Transbond XT; B Transbond Plus self-etch primer; and two self-etch bonding systems reinforced with silica dioxide nanofiller at different concentrations: C Futurabond DC at 1%; D Optibond All-in-One at 7%. Each group was allocated into two subgroups (n = 12 according to experimental time (12 and 24 hours. SBS test was performed using a universal testing machine. ARI scores were determined under a stereomicroscope. Scanning electron microscopy (SEM and transmission electron microscopy (TEM were used to determine the size and distribution of nanofillers. One-way ANOVA was used to compare SBS followed by the post-hoc Tukey test. The chi-square test was used to evaluate ARI scores. Results: Mean SBS of Futurabond DC and Optibond All-in-One were significantly lower than conventional system, and there were no significant differences between means SBS obtained with all self-etch bonding systems used in the study. Lower ARI scores were found for Futurabond DC and Optibond All-in-One. There was no significant difference of SBS and ARI obtained at either time points for all bonding systems. Relative homogeneous distribution of the fillers was observed with the bonding systems. Conclusion: Two nanofilled systems revealed the lowest bond strengths, but still clinically acceptable and less adhesive was left on enamel. It is advisable not to load the brackets immediately to the maximum.

  4. Effect of nanotechnology in self-etch bonding systems on the shear bond strength of stainless steel orthodontic brackets

    Science.gov (United States)

    Hammad, Shaza M.; El-Wassefy, Noha; Maher, Ahmed; Fawakerji, Shafik M.

    2017-01-01

    ABSTRACT Objective: To evaluate the effect of silica dioxide (SiO2) nanofillers in different bonding systems on shear bond strength (SBS) and mode of failure of orthodontic brackets at two experimental times. Methods: Ninety-six intact premolars were divided into four groups: A) Conventional acid-etch and primer Transbond XT; B) Transbond Plus self-etch primer; and two self-etch bonding systems reinforced with silica dioxide nanofiller at different concentrations: C) Futurabond DC at 1%; D) Optibond All-in-One at 7%. Each group was allocated into two subgroups (n = 12) according to experimental time (12 and 24 hours). SBS test was performed using a universal testing machine. ARI scores were determined under a stereomicroscope. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to determine the size and distribution of nanofillers. One-way ANOVA was used to compare SBS followed by the post-hoc Tukey test. The chi-square test was used to evaluate ARI scores. Results: Mean SBS of Futurabond DC and Optibond All-in-One were significantly lower than conventional system, and there were no significant differences between means SBS obtained with all self-etch bonding systems used in the study. Lower ARI scores were found for Futurabond DC and Optibond All-in-One. There was no significant difference of SBS and ARI obtained at either time points for all bonding systems. Relative homogeneous distribution of the fillers was observed with the bonding systems. Conclusion: Two nanofilled systems revealed the lowest bond strengths, but still clinically acceptable and less adhesive was left on enamel. It is advisable not to load the brackets immediately to the maximum. PMID:28444018

  5. Shear Bond Strength of DentStat(trademark) for Bracket Bonding to Gold, Ceramic, and Enamel

    Science.gov (United States)

    2012-12-21

    they make a good choice for orthodontic bracket retention. According to a Cochrane review by Mandall (Mandall et al, 2002) all of their review...was developed as a temporary material for use in military field environments, can be used to effectively bond orthodontic brackets to type III gold... orthodontic composite resin adhesive, Transbond XTTM (3M Unitek Monrovia, California), as they are used to bond orthodontic brackets to gold

  6. Influence of different etching modes on bond strength and fatigue strength to dentin using universal adhesive systems.

    Science.gov (United States)

    Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Berry, Thomas P; Watanabe, Hedehiko; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

    2016-02-01

    The purpose of this study was to determine the dentin bonding ability of three new universal adhesive systems under different etching modes using fatigue testing. Prime & Bond elect [PE] (DENTSPLY Caulk), Scotchbond Universal [SU] (3M ESPE), and All Bond Universal [AU] (Bisco) were used in this study. A conventional single-step self-etch adhesive, Clearfil Bond SE ONE [CS] (Kuraray Noritake Dental) was also included as a control. Shear bond strengths (SBS) and shear fatigue strength (SFS) to human dentin were obtained in the total-etch mode and self-etch modes. For each test condition, 15 specimens were prepared for the SBS and 30 specimens for SFS. SEM was used to examine representative de-bonded specimens, treated dentin surfaces and the resin/dentin interface for each test condition. Among the universal adhesives, PE in total-etch mode showed significantly higher SBS and SFS values than in self-etch mode. SU and AU did not show any significant difference in SBS and SFS between the total-etch mode and self-etch mode. However, the single-step self-etch adhesive CS showed significantly lower SBS and SFS values in the etch-and-rinse mode when compared to the self-etch mode. Examining the ratio of SFS/SBS, for PE and AU, the etch-and-rinse mode groups showed higher ratios than the self-etch mode groups. The influence of different etching modes on dentin bond quality of universal adhesives was dependent on the adhesive material. However, for the universal adhesives, using the total-etch mode did not have a negative impact on dentin bond quality. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  7. Composite shear bond strength to dry and wet enamel with three self-etch adhesives

    Directory of Open Access Journals (Sweden)

    Shafiee F

    2006-01-01

    Full Text Available Background and Aim: The bonding mechanisms of self etching primers, based upon the simultaneous etching and priming of dentin, simplifies the bonding technique, but the efficiency of these systems is still controversial. This study compared the shear bond strength of three self etch adhesive systems in dry and wet conditions. Materials and Method: In this experimental study, 77 intact bovine lower incisors with flat 600 grit sanded enamel surface were fixed in acrylic molds and divided into 7 groups, of 11 teeth. The enamel surfaces were treated according to a special procedure as follows: Group 1: Prompt L-Pop (PLP in dry condition, Group 2: Prompt L-Pop in wet condition, Group 3: Clearfield SE Bond (CSEB in dry condition, Group 4: Clearfield SE Bond in wet condition, Group 5: iBond (iB in dry condition, Group 6: iBond in wet condition, Group 7: Margin Bond (Control in dry condition. Surfaces were air dried for ten seconds, or blot dried in wet condition. Composite resin was bonded on the enamel and built up by applying a cylindric teflon split mold (4 mm height 2mm diameter. After 24 hours storage in dionized water at room temperature, all specimens were thermocycled and shear bond test was employed by a universal testing machine (Instron with a cross-head speed of 1mm/min. The shear bond strength was recorded in MPa and data were analyzed with ANOVA and Scheffe statistical tests. P<0.05 was considered as statistically significant. The mode of failure was examined under a stereomicroscope. Results: 1- Shear bond strength of CSEB in dry condition (21.5 ± 4.8 MPa was significantly higher than PLP and iB groups (p<0.0001. 2- Shear bond strength of iB and PLP groups in dry condition (9.60 ± 2.2, 9.49 ± 3 MPa were significantly lower than CSEB and control (2.99 ± 5.1 MPa (P<0.0001. 3- There was no significant difference between PLP and iB groups in dry condition (P=1. 4- Shear bond strength of CSEB in wet condition (21.8 ± 3 MPa was

  8. Effects of surface treatment on bond strength between dental resin agent and zirconia ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Moradabadi, Ashkan [Department of Electrochemistry, Universität Ulm, Ulm (Germany); Roudsari, Sareh Esmaeily Sabet [Department of Optoelectonics, Universität Ulm, Ulm (Germany); Yekta, Bijan Eftekhari [School of Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Rahbar, Nima, E-mail: nrahbar@wpi.edu [Department of Civil and Environmental Engineering, Worcester Polytechnic Institute, Worcester, MA 01609 (United States)

    2014-01-01

    This paper presents the results of an experimental study to understand the dominant mechanism in bond strength between dental resin agent and zirconia ceramic by investigating the effects of different surface treatments. Effects of two major mechanisms of chemical and micromechanical adhesion were evaluated on bond strength of zirconia to luting agent. Specimens of yttrium-oxide-partially-stabilized zirconia blocks were fabricated. Seven groups of specimens with different surface treatment were prepared. 1) zirconia specimens after airborne particle abrasion (SZ), 2) zirconia specimens after etching (ZH), 3) zirconia specimens after airborne particle abrasion and simultaneous etching (HSZ), 4) zirconia specimens coated with a layer of a Fluorapatite-Leucite glaze (GZ), 5) GZ specimens with additional acid etching (HGZ), 6) zirconia specimens coated with a layer of salt glaze (SGZ) and 7) SGZ specimens after etching with 2% HCl (HSGZ). Composite cylinders were bonded to airborne-particle-abraded surfaces of ZirkonZahn specimens with Panavia F2 resin luting agent. Failure modes were examined under 30 × magnification and the effect of surface treatments was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SZ and HSZ groups had the highest and GZ and SGZ groups had the lowest mean shear bond strengths among all groups. Mean shear bond strengths were significantly decreased by applying a glaze layer on zirconia surfaces in GZ and SGZ groups. However, bond strengths were improved after etching process. Airborne particle abrasion resulted in higher shear bond strengths compared to etching treatment. Modes of failure varied among different groups. Finally, it is concluded that micromechanical adhesion was a more effective mechanism than chemical adhesion and airborne particle abrasion significantly increased mean shear bond strengths compared with another surface treatments. - Highlights: • Understanding the dominant mechanism of bonding

  9. Effects of green tea on the shear bond strength of orthodontic brackets after in-office vital bleaching.

    Science.gov (United States)

    Berger, Sandrine Bittencourt; Guiraldo, Ricardo Danil; Lopes, Murilo Baena; Oltramari-Navarro, Paula Vanessa; Fernandes, Thais Maria; Schwertner, Renata de Castro Alves; Ursi, Wagner José Silva

    2016-01-01

    The application of bleaching agents before placement of resin-bonded fixed appliances significantly, but temporarily, reduces bond strength to tooth structure. Antioxidants have been studied as a means to remove residual oxygen that compromises bonding to bleached enamel. This in vitro study evaluated whether green tea (GT) could restore the shear bond strength between bonded orthodontic brackets and bleached enamel. Six experimental groups were compared: group 1, no bleaching plus bracket bonding (positive control); group 2, bleaching with 35% hydrogen peroxide (HP) plus bracket bonding (negative control); group 3, 35% HP plus 10% sodium ascorbate (SA) plus bracket bonding; group 4, 35% HP plus 10% GT plus bracket bonding; group 5, no bleaching plus 10% SA plus bracket bonding; group 6, no bleaching plus 10% GT plus bracket bonding. Results suggested that GT, like SA, may be beneficial for bracket bonding immediately after bleaching.

  10. Effect of light aging on silicone-resin bond strength in maxillofacial prostheses.

    Science.gov (United States)

    Polyzois, Gregory; Pantopoulos, Antonis; Papadopoulos, Triantafillos; Hatamleh, Muhanad

    2015-04-01

    The aim of this study was to investigate the effect of accelerated light aging on bond strength of a silicone elastomer to three types of denture resin. A total of 60 single lap joint specimens were fabricated with auto-, heat-, and photopolymerized (n = 20) resins. An addition-type silicone elastomer (Episil-E) was bonded to resins treated with the same primer (A330-G). Thirty specimens served as controls and were tested after 24 hours, and the remaining were aged under accelerated exposure to daylight for 546 hours (irradiance 765 W/m(2) ). Lap shear joint tests were performed to evaluate bond strength at 50 mm/min crosshead speed. Two-way ANOVA and Tukey's test were carried out to detect statistical significance (p Accelerated light aging for 546 hours affects the bond strength of an addition-type silicone elastomer to three different denture resins. The bond strength significantly increased after aging for photo- and autopolymerized resins. All the bonds failed adhesively. © 2014 by the American College of Prosthodontists.

  11. Effect of Luting Cements On the Bond Strength to Turkom-Cera All-Ceramic Material

    Science.gov (United States)

    Al–Makramani, Bandar M. A.; Razak, Abdul A. A.; Abu–Hassan, Mohamed I.; Al–Sanabani, Fuad A.; Albakri, Fahad M.

    2018-01-01

    BACKGROUND: The selection of the appropriate luting cement is a key factor for achieving a strong bond between prepared teeth and dental restorations. AIM: To evaluate the shear bond strength of Zinc phosphate cement Elite, glass ionomer cement Fuji I, resin-modified glass ionomer cement Fuji Plus and resin luting cement Panavia-F to Turkom-Cera all-ceramic material. MATERIALS AND METHODS: Turkom-Cera was used to form discs 10mm in diameter and 3 mm in thickness (n = 40). The ceramic discs were wet ground, air - particle abraded with 50 - μm aluminium oxide particles and randomly divided into four groups (n = 10). The luting cement was bonded to Turkom-Cera discs as per manufacturer instructions. The shear bond strengths were determined using the universal testing machine at a crosshead speed of 0.5 mm/min. The data were analysed using the tests One Way ANOVA, the nonparametric Kruskal - Wallis test and Mann - Whitney Post hoc test. RESULTS: The shear bond strength of the Elite, Fuji I, Fuji Plus and Panavia F groups were: 0.92 ± 0.42, 2.04 ± 0.78, 4.37 ± 1.18, and 16.42 ± 3.38 MPa, respectively. There was the statistically significant difference between the four luting cement tested (p < 0.05). CONCLUSION: the phosphate-containing resin cement Panavia-F exhibited shear bond strength value significantly higher than all materials tested. PMID:29610618

  12. Shear bond strength of amalgam to dentin using different dentin adhesive systems

    Directory of Open Access Journals (Sweden)

    Farimah Sardari

    2012-01-01

    Full Text Available Background and Aims: The aim of this in vitro study was to assess the shear bond strength of amalgam to dentin using four dentin adhesive systems.Materials and Methods: One hundred human molars were selected. After enamel removal, a dentin cylinder with 3 mm thickness was prepared. Eighty specimens were resorted with amalgam and four dentin adhesive systems as follows (n=20: group 1, Scotch Bond Multi-Purpose; group 2, One Coat Bond; group 3, PQ1; and group 4, Panavia-F. In group 5, 20 specimens were resorted with amalgam and varnish as control group. The specimens were incubated at 37°C for 24 h. The shear bond strengths were then measured by using push out method. The data were analyzed by one-way ANOVA and post hoc Duncan's tests.Results: Mean values for bond strengths of test groups were as follows: group 1=21.03±8.9, group 2=23.47±9, group 3=13.16±8.8, group 4=20.07±8.9 and group 5=14.15±8.7 MPa±SD. One-way ANOVA showed the statistically significant difference between the bond strengths of five groups (P=0.001. Post hoc Duncan's test showed significant difference between groups 1and 3 (P=0.008, groups 1 and 5 (P=0.019, groups 2 and 5 (P=0.0008, groups 4 and 5 (P=0.042, and groups 3 and 4 (P=0.018.Conclusion: Results of this study showed that the bond strength of amalgam to dentin using One Coat Bond as dentin adhesive system was higher than that observed in other dentin adhesive systems.

  13. Does 8-methacryloxyoctyl trimethoxy silane (8-MOTS) improve initial bond strength on lithium disilicate glass ceramic?

    Science.gov (United States)

    Maruo, Yukinori; Nishigawa, Goro; Yoshihara, Kumiko; Minagi, Shogo; Matsumoto, Takuya; Irie, Masao

    2017-03-01

    Dental ceramic surfaces are modified with silane coupling agents, such as γ-methacryloxypropyl trimethoxy silane (γ-MPTS), to improve bond strength. For bonding between lithium disilicate glass ceramic and resin cement, the objective was to investigate if 8-methacryloxyoctyl trimethoxy silane (8-MOTS) could yield a similar performance as the widely used γ-MPTS. One hundred and ten lithium disilicate glass ceramic specimens were randomly divided into 11 groups (n=10) according to pretreatment regime. All specimens were pretreated with a different solution composed of one or a combination of these agents: 10 or 20wt% silane coupling agent of γ-MPTS or 8-MOTS, followed by a hydrolysis solution of acetic acid or 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). Each pretreated surface was luted to a stainless steel rod of 3.6mm diameter and 2.0mm height with resin cement. Shear bond strength between ceramic and cement was measured after 24-h storage in 37°C distilled water. 8-MOTS produced the same bonding performance as γ-MPTS. Both silane coupling agents significantly increased the bond strength of resin cement, depending on their concentration. When activated by 10-MDP hydrolysis solution, 20wt% concentration produced the highest values (γ-MPTS: 24.9±5.1MPa; 8-MOTS: 24.6±7.4MPa). Hydrolysis with acetic acid produced lower bond strengths than with 10-MDP. Silane coupling pretreatment with 8-MOTS increased the initial bond strength between lithium disilicate glass ceramic and resin cement, rendering the same bonding effect as the conventional γ-MPTS. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  14. Shear bond strength of three adhesive systems to enamel and dentin of permanent teeth

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    Niloofar Shadman

    2012-01-01

    Full Text Available Background and Aims: The purpose of this experimental study was to investigate the shear bond strength of three new adhesive systems to enamel and dentin of permanent human teeth using three new etch and rinse and self-etch adhesive systems.Materials and Methods: Sixty intact caries-free third molars were selected and randomly divided into 6 groups. Flat buccal and lingual enamel and dentin surfaces were prepared and mounted in the acrylic resin perpendicular to the plan of the horizon. Adhesives used in this study were Tetric N-Bond, AdheSE and AdheSE-One F (Ivoclar/Vivadent, Schaan, Liechtenstein. The adhesives were applied on the surfaces and cured with quartz tungsten halogen curing unit (600 mW/cm2 intensity for 20 s. After attaching composite to the surfaces and thermocycling (500 cycles, 5-55ºC, shear bond strength was measured using a universal testing machine at a crosshead speed of 0.5 mm/min. The failure modes were examined under a stereomicroscope. The data were statistically analyzed using T-test, one-way ANOVA, Tukey and Fisher's exact tests.Results: In enamel, Tetric N-Bond (28.57±4.58 MPa and AdheSE (21.97±7.6 MPa had significantly higher bond strength than AdheSE-One F (7.16±2.09 MPa (P0.05.Conclusion: Shear bond strength to dentin in Tetric N-Bond (etch and rinse system( was higher than self-etch adhesives (AdheSE and AdheSE-One F. The bond strength to enamel and dentin in two-step self-etch (AdheSE was higher than one-step self-etch (AdheSE-One F.

  15. Computer-aided study of key factors determining high mechanical properties of nanostructured surface layers in metal-ceramic composites

    Science.gov (United States)

    Konovalenko, Igor S.; Shilko, Evgeny V.; Ovcharenko, Vladimir E.; Psakhie, Sergey G.

    2017-12-01

    The paper presents the movable cellular automaton method. It is based on numerical models of surface layers of the metal-ceramic composite NiCr-TiC modified under electron beam irradiation in inert gas plasmas. The models take into account different geometric, concentration and mechanical parameters of ceramic and metallic components. The authors study the contributions of key structural factors in mechanical properties of surface layers and determine the ranges of their variations by providing the optimum balance of strength, strain hardening and fracture toughness.

  16. An Investigation of Bond Strength of Reinforcing Bars in Fly Ash and GGBS Based Geopolymer Concrete

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    Boopalan C.

    2017-01-01

    Full Text Available Geopolymers are amorphous aluminosilicate materials. Geopolymers are binders formed by alkali activation of Geopolymer Source Materials (GSM using an alkaline activator solution. Concretes made using Geopolymer binders are excellent alternative to the Ordinary Portland Cement concretes from strength, durability, and ecological considerations. Especially, usage of industrial waste materials such as Fly Ash and Slags as GSMs considerably lower the carbon footprint of concrete and mitigate the damage due to the unscientific dumping/disposal of these materials. To use the Geopolymer concrete (GPC for reinforced structural members, the composite action of reinforcing bars with Geopolymer concrete i.e. the bond behaviour should be well understood. This paper describes the bond behaviour of 12mm and 16mm dia. bars embedded in Fly ash and GGBS based Geopolymer concrete and conventional Portland Pozzolana cement concrete specimens investigated using the pull-out tests as per Indian Standard Code IS:2770(Part-I; the bond stresses and corresponding slips were found out. The bond stress increased with increase in compressive strength. The peak bond stress was found to be 4.3 times more than the design bond stress as per IS:456-2000. The Geopolymer concretes possess higher bond strength compared to the conventional cement concretes.

  17. Effect of Dentin Wetness on the Bond Strength of Universal Adhesives

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    An-Na Choi

    2017-10-01

    Full Text Available The effects of dentin wetness on the bond strength and adhesive interface morphology of universal adhesives have been investigated using micro-tensile bond strength (μTBS testing and confocal laser scanning microscopy (CLSM. Seventy-two human third molars were wet ground to expose flat dentin surfaces. They were divided into three groups according to the air-drying time of the dentin surfaces: 0 (without air drying, 5, and 10 s. The dentin surfaces were then treated with three universal adhesives: G-Premio Bond, Single Bond Universal, and All-Bond Universal in self-etch or etch-and-rinse mode. After composite build up, a μTBS test was performed. One additional tooth was prepared for each group by staining the adhesives with 0.01 wt % of Rhodamine B fluorescent dye for CLSM analysis. The data were analyzed statistically using ANOVA and Tukey’s post hoc tests (α = 0.05. Two-way ANOVA showed significant differences among the adhesive systems and dentin moisture conditions. An interaction effect was also observed (p < 0.05. One-way ANOVA showed that All-Bond Universal was the only material influenced by the wetness of the dentin surfaces. Wetness of the dentin surface is a factor influencing the micro-tensile bond strength of universal adhesives.

  18. Influence of intrapulpal pressure simulation on the bond strength of adhesive systems to dentin

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    Marcio Vivan Cardoso

    2008-06-01

    Full Text Available The purpose of this study was to evaluate the influence of intrapulpal pressure simulation on the bonding effectiveness of etch & rinse and self-etch adhesives to dentin. Eighty sound human molars were distributed into eight groups, according to the permeability level of each sample, measured by an apparatus to assess hydraulic conductance (Lp. Thus, a similar mean permeability was achieved in each group. Three etch & rinse adhesives (Prime & Bond NT - PB, Single Bond -SB, and Excite - EX and one self-etch system (Clearfil SE Bond - SE were employed, varying the presence or absence of an intrapulpal pressure (IPP simulation of 15 cmH2O. After adhesive and restorative procedures were carried out, the samples were stored in distilled water for 24 hours at 37°C, and taken for tensile bond strength (TBS testing. Fracture analysis was performed using a light microscope at 40 X magnification. The data, obtained in MPa, were then submitted to the Kruskal-Wallis test ( a = 0.05. The results revealed that the TBS of SB and EX was significantly reduced under IPP simulation, differing from the TBS of PB and SE. Moreover, SE obtained the highest bond strength values in the presence of IPP. It could be concluded that IPP simulation can influence the bond strength of certain adhesive systems to dentin and should be considered when in vitro studies are conducted.

  19. A comparison of finite element analysis with in vitro bond strength tests of the bracket-cement-enamel system

    NARCIS (Netherlands)

    Algera, T.J.; Feilzer, A.J.; Prahl-Andersen, B.; Kleverlaan, C.J.

    2011-01-01

    The aim of this study was to determine the in vitro shear bond strength (SBS) and tensile bond strength (TBS) of 45 metal brackets bonded with Transbond XT to bovine enamel. The SBS was determined by loading the short and the long sides of the bracket base. Testing took place after storage of the

  20. Bond strength of orthodontic light-cured resin-modified glass ionomer cement.

    Science.gov (United States)

    Cheng, Hsiang Yu; Chen, Chien Hsiu; Li, Chuan Li; Tsai, Hung Huey; Chou, Ta Hsiung; Wang, Wei Nan

    2011-04-01

    The purpose of this study was to compare the bond strengths and debonded interfaces achieved with light-cured resin-modified glass ionomer cement (RMGIC) and conventional light-cured composite resin. In addition, the effects of acid etching and water contamination were examined. One hundred human premolars were randomly divided into five equal groups. The mini Dyna-lock upper premolar bracket was selected for testing. The first four groups were treated with light-cured RMGIC with or without 15 per cent phosphoric acid-etching treatment and with or without water contamination preceding bracket bonding. The control samples were treated with the conventional light-cured Transbond composite resin under acid etching and without water contamination. Subsequently, the brackets were debonded by tensile force using an Instron machine. The modified adhesive remnant index (ARI) scores were assigned to the bracket base of the debonded interfaces using a scanning electron microscope. The bond strength and modified ARI scores were determined and analysed statistically by one-way analysis of variance and chi-square test. Under all four conditions, the bond strength of the light-cure RMGIC was equal to or higher than that of the conventional composite resin. The highest bond strength was achieved when using RMGIC with acid etching but without water contamination. The modified ARI scores were 2 for Fuji Ortho LC and 3 for Transbond. No enamel detachment was found in any group. Fifteen per cent phosphoric acid etching without moistening the enamel of Fuji Ortho LC provided the more favourable bond strength. Enamel surfaces, with or without water contamination and with or without acid etching, had the same or a greater bond strength than Transbond.

  1. Shear bond strength of different adhesive systems to normal and caries-affected dentin

    Directory of Open Access Journals (Sweden)

    Niloofar Shadman

    2015-10-01

    Full Text Available BACKGROUND AND AIM: According to the effect of the adhesive and substrate type on the bond strength, examination of the adhesive is required in all aspects. The aim of this study was to evaluate the shear bond strength of different adhesive systems to normal dentin (ND and caries affected dentin (CAD in permanent teeth. METHODS: Thirty extracted molars with small occlusal caries were selected. After preparation and determination of ND and CAD by caries detector, teeth were divided into three groups and treated with one of the two tested adhesives: Single Bond 2 (SB2, Scotchbond Universal with etch (SBU-ER, and Scotchbond Universal without etch (SBU-SE. Then composite (Filtek Z-250 XT were attached to the surfaces and cured. After water storage (24 hours and thermocycling (500 cycles 5-55 °C, bond strength was calculated and failure modes were determined by stereomicroscope. The data were analyzed by one-way ANOVA and post-hoc test [Tukey HSD (honest significant difference] and with P ˂ 0.050 as the level of significance. RESULTS: Only SBU-ER had significantly higher shear bond strength than SBU-SE in ND (P = 0.027 and CAD (P = 0.046. Bond strength in SBU-ER the highest and in SBU-SE had the lowest amounts in CAD and ND. There was no significant difference in each group between ND and CAD. CONCLUSION: The 2-step etch-and-rinse adhesive (SBU-ER had higher bond strength to ND and CAD than the selfetch adhesive (SBU-SE.

  2. Influence of matrix metalloproteinase synthetic inhibitors on dentin microtensile bond strength of resin cements.

    Science.gov (United States)

    Stape, T H S; Menezes, M S; Barreto, B C F; Aguiar, F H B; Martins, L R; Quagliatto, P S

    2012-01-01

    This study evaluated the effect of dentin pretreatment with 2% chlorhexidine (CHX) or 24% ethylenediamine tetra-acetic acid gel (EDTA) on the dentin microtensile bond strength (μTBS) of resin cements. Composite blocks were luted to superficial noncarious human dentin (n=10) using two resin cements (RelyX ARC [ARC] and RelyX U100 [U100]) and three dentin pretreatments (without pretreatment-control, CHX, and EDTA). CHX was applied for 60 seconds on the acid-etched dentin in the ARC/CHX group, and for the same time on smear layer-covered dentin in the U100/CHX group. EDTA was applied for 45 seconds on smear-covered dentin in the U100/EDTA group, and it replaced phosphoric acid conditioning in the ARC/EDTA group for 60 seconds. After storage in water for 24 hours, specimens were prepared for microtensile bond strength testing. The results were submitted to two-way analysis of variance (ANOVA) followed by Tukey test. ARC produced significantly higher μTBS (pEDTA was used. For ARC, no pretreatment and CHX produced higher μTBS than EDTA. For U100, EDTA produced higher μTBS; no statistical difference occurred between CHX pretreatment and when no pretreatment was performed. While CHX did not affect immediate dentin bond strength of both cements, EDTA improved bond strength of U100, but it reduced dentin bond strength of ARC.

  3. The effect of thermocycling on tensile bond strength of two soft liners.

    Science.gov (United States)

    Geramipanah, Farideh; Ghandari, Masoumeh; Zeighami, Somayeh

    2013-09-01

    Failure of soft liners depends mostly on separation from the denture base resin; therefore measurement of the bond strength is very important. The purpose of this study was to compare the tensile bond strength of two soft liners (Acropars, Molloplast-B) to denture base resin before and after thermocycling. Twenty specimens fromeach of the two different soft liners were processed according to the manufacturer's instructions between two polymethyl methacrylate (PMMA) sheets. Ten specimens in each group were maintained in 37°C water for 24 hours and 10 were thermocycled (5000 cycles) among baths of 5° and 55°C. The tensile bond strength was measured using a universal testing machine at a crosshead speed of 5 mm/min. Mode of failure was determined with SEM (magnification ×30). Two-way ANOVA was used to analyze the data. The mean and standard deviation of tensile bond strength of Acropars and Molloplast-B before thermocycling were 6.59±1.85 and1.51±0.22 MPa, respectively and 5.89±1.52 and1.37±0.18 MPa, respectively after thermocycling. There was no significant difference before and after thermocycling. Mode of failure in Acropars and Molloplast-B were adhesive and cohesive, respectivley. The bond strength of Acropars was significantly higher than Molloplast-B (P<0.05).

  4. The effect of ultrafast fiber laser application on the bond strength of resin cement to titanium.

    Science.gov (United States)

    Ates, Sabit Melih; Korkmaz, Fatih Mehmet; Caglar, Ipek Satıroglu; Duymus, Zeynep Yeşil; Turgut, Sedanur; Bagis, Elif Arslan

    2017-07-01

    The purpose of this study was to investigate the effect of ultrafast fiber laser treatment on the bond strength between titanium and resin cement. A total of 60 pure titanium discs (15 mm × 2 mm) were divided into six test groups (n = 10) according to the surface treatment used: group (1) control, machining; group (2) grinding with a diamond bur; group (3) ultrafast fiber laser application; group (4) resorbable blast media (RBM) application; group (5) electro-erosion with copper; and group (6) sandblasting. After surface treatments, resin cements were applied to the treated titanium surfaces. Shear bond strength testing of the samples was performed with a universal testing machine after storing in distilled water at 37 °C for 24 h. One-way ANOVA and Tukey's HSD post hoc test were used to analyse the data (P < 0.05). The highest bond strength values were observed in the laser application group, while the lowest values were observed in the grinding group. Sandblasting and laser application resulted in significantly higher bond strengths than control treatment (P < 0.05). Ultrafast fiber laser treatment and sandblasting may improve the bond strength between resin cement and titanium.

  5. UV irradiation improves the bond strength of resin cement to fiber posts.

    Science.gov (United States)

    Zhong, Bo; Zhang, Yong; Zhou, Jianfeng; Chen, Li; Li, Deli; Tan, Jianguo

    2011-01-01

    The purpose is to evaluate the effect of UV irradiation on the bond strength between epoxy-based glass fiber posts and resin cement. Twelve epoxy-based glass fiber posts were randomly divided into three groups. Group 1 (Cont.): No surface treatment. Group 2 (Low-UV): UV irradiation was conducted from a distance of 10 cm for 10 min. Group 3 (High-UV): UV irradiation was conducted from a distance of 1 cm for 3 min. A resin cement (CLEARFIL SA LUTING) was used for the post cementation to form resin slabs which contained fiber posts in the center. Microtensile bond strengths were tested and the mean bond strengths (MPa) were 18.81 for Cont. group, 23.65 for Low-UV group, 34.75 for High-UV group. UV irradiation had a significant effect on the bond strength (pUV irradiation demonstrates its capability to improve the bond strength between epoxy-based glass fiber posts and resin cement.

  6. Fragmentation and bond strength of airborne diesel soot agglomerates

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    Messerer Armin

    2008-06-01

    Full Text Available Abstract Background The potential of diesel soot aerosol particles to break up into smaller units under mechanical stress was investigated by a direct impaction technique which measures the degree of fragmentation of individual agglomerates vs. impact energy. Diesel aerosol was generated by an idling diesel engine used for passenger vehicles. Both the aerosol emitted directly and aerosol that had undergone additional growth by Brownian coagulation ("aging" was investigated. Optionally a thermo-desoption technique at 280°C was used to remove all high-volatility and the majority of low-volatility HC adsorbates from the aerosol before aging. Results It was found that the primary soot agglomerates emitted directly from the engine could not be fragmented at all. Soot agglomerates permitted to grow additionally by Brownian coagulation of the primary emitted particles could be fragmented to a maximum of 75% and 60% respectively, depending on whether adsorbates were removed from their surface prior to aging or not. At most, these aged agglomerates could be broken down to roughly the size of the agglomerates from the primary emission. The energy required for a 50% fragmentation probability of all bonds within an agglomerate was reduced by roughly a factor of 2 when aging "dry" agglomerates. Average bond energies derived from the data were 0.52*10-16 and 1.2*10-16 J, respectively. This is about 2 orders of magnitude higher than estimates for pure van-der-Waals agglomerates, but agrees quite well with other observations. Conclusion Although direct conclusions regarding the behavior of inhaled diesel aerosol in contact with body fluids cannot be drawn from such measurements, the results imply that highly agglomerated soot aerosol particles are unlikely to break up into units smaller than roughly the size distribution emitted as tail pipe soot.

  7. Fragmentation and bond strength of airborne diesel soot agglomerates

    Science.gov (United States)

    Rothenbacher, Sonja; Messerer, Armin; Kasper, Gerhard

    2008-01-01

    Background The potential of diesel soot aerosol particles to break up into smaller units under mechanical stress was investigated by a direct impaction technique which measures the degree of fragmentation of individual agglomerates vs. impact energy. Diesel aerosol was generated by an idling diesel engine used for passenger vehicles. Both the aerosol emitted directly and aerosol that had undergone additional growth by Brownian coagulation ("aging") was investigated. Optionally a thermo-desoption technique at 280°C was used to remove all high-volatility and the majority of low-volatility HC adsorbates from the aerosol before aging. Results It was found that the primary soot agglomerates emitted directly from the engine could not be fragmented at all. Soot agglomerates permitted to grow additionally by Brownian coagulation of the primary emitted particles could be fragmented to a maximum of 75% and 60% respectively, depending on whether adsorbates were removed from their surface prior to aging or not. At most, these aged agglomerates could be broken down to roughly the size of the agglomerates from the primary emission. The energy required for a 50% fragmentation probability of all bonds within an agglomerate was reduced by roughly a factor of 2 when aging "dry" agglomerates. Average bond energies derived from the data were 0.52*10-16 and 1.2*10-16 J, respectively. This is about 2 orders of magnitude higher than estimates for pure van-der-Waals agglomerates, but agrees quite well with other observations. Conclusion Although direct conclusions regarding the behavior of inhaled diesel aerosol in contact with body fluids cannot be drawn from such measurements, the results imply that highly agglomerated soot aerosol particles are unlikely to break up into units smaller than roughly the size distribution emitted as tail pipe soot. PMID:18533015

  8. Effect of thermal aging on the tensile bond strength at reduced areas of seven current adhesives.

    Science.gov (United States)

    Baracco, Bruno; Fuentes, M Victoria; Garrido, Miguel A; González-López, Santiago; Ceballos, Laura

    2013-07-01

    The purpose of this study was to determine the micro-tensile bond strength (MTBS) to dentin of seven adhesive systems (total and self-etch adhesives) after 24 h and 5,000 thermocycles. Dentin surfaces of human third molars were exposed and bonded with two total-etch adhesives (Adper Scotchbond 1 XT and XP Bond), two two-step self-etch adhesives (Adper Scotchbond SE and Filtek Silorane Adhesive System) and three one-step self-etch adhesives (G-Bond, Xeno V and Bond Force). All adhesive systems were applied following manufacturers' instructions. Composite buildups were constructed and the bonded teeth were then stored in water (24 h, 37 °C) or thermocycled (5,000 cycles) before being sectioned and submitted to MTBS test. Two-way ANOVA and subsequent comparison tests were applied at α = 0.05. Characteristic de-bonded specimens were analyzed using scanning electron microscopy (SEM). After 24 h water storage, MTBS values were highest with XP Bond, Adper Scotchbond 1 XT, Filtek Silorane Adhesive System and Adper Scotchbond SE and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. After thermocycling, MTBS values were highest with XP Bond, followed by Filtek Silorane Adhesive System, Adper Scotchbond SE and Adper Scotchbond 1 XT and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. Thermal aging induced a significant decrease in MTBS values with all adhesives tested. The resistance of resin-dentin bonds to thermal-aging degradation was material dependent. One-step self-etch adhesives obtained the lowest MTBS results after both aging treatments, and their adhesive capacity was significantly reduced after thermocycling.

  9. Bond strength of a composite resin to glass ionomer cements using different adhesive systems

    Directory of Open Access Journals (Sweden)

    Ana Carolina de Oliveira BECCI

    2017-08-01

    Full Text Available Abstract Introduction Glass ionomer cements are often used as a base or cavity lining prior to restorative material. Objective To evaluate the bond strength of a composite resin to different glass ionomer cements, when using a two-step conventional and self-etching adhesive systems. Material and method Three glass ionomer cements (Ketac Molar Easymix, Vitremer and Vitrebond, the composite resin Filtek Z350 XT and the adhesive systems Adper Single Bond 2, Clearfil SE Bond and Adper Easy One were used. As negative control, resin was bonded to cement without using an adhesive system. Holes (4 mm diameter, 2 mm deep prepared in acrilic bloks were filled with the glass ionomer cements (n=12/group. On the surface, an area of 1mm in diameter was delimited, the adhesive system was applied, and a specimen of composite resin with 1 mm height was made. After 24 hours storage (37 °C and 100% humidity, the microshear test was performed. Data were analyzed using two-way ANOVA and Tukey test for comparison between groups (α=0.05. Result The adhesive systems significantly improved the bond strenght of composite resin to glass ionomer cements (p≤0.001. There was no significant difference in bond strength when self-etching adhesive systems were compared with the simplified etch-and-rinse adhesive, except for Vitrebond where Clearfil SE Bond determined higher bond strength when compared to Adper Single Bond 2 (p=0.003. Conclusion Self-etching adhesive systems are a good option for establishing the bond between the composite resin and the glass ionomer cement.

  10. Numerical and experimental analysis of thermosonic bond strength considering interfacial contact phenomena

    International Nuclear Information System (INIS)

    He Jun; Guo Yongjin; Lin Zhongqin

    2008-01-01

    The theoretical equation of thermosonic bond strength involving interfacial deformation and microcontact phenomena is presented in this study. The constitutive equation of gold considering the ultrasonic softening mechanism was developed based on the thermosonic bonding experiments and coded into the FE software. The numerical model of bonding was established to estimate the surface exposure and the effective normal pressure. The real contact area was calculated by a microcontact model. Accordingly, the nominal bond strength can be obtained and verified by the experimental data. It is found that a better conjunction exists at the edge of the contact area because large surface exposure is produced there, which is also proved by the SEM image of a sheared ball bond. Increasing the bonding force or the ultrasonic power will increase the interfacial plastic deformation, the nominal and real contact areas, but decreases the effective normal pressure. The contact ratio increases to a maximum with the increase in the bonding force, and then decreases while it continues to decrease with the increase in the ultrasonic power. In addition, both the stress analysis and experimental result show that cratering and damage to the pad structure are easily produced below the edge region of the contact area under an excessive bonding force or ultrasonic power

  11. Comparison of shear bond strength of universal adhesives on etched and nonetched enamel.

    Science.gov (United States)

    Beltrami, Riccardo; Chiesa, Marco; Scribante, Andrea; Allegretti, Jessica; Poggio, Claudio

    2016-04-06

    The purpose of this study was to evaluate the effect of surface pretreatment with 37% phosphoric acid on the enamel bond strength of different universal adhesives. One hundred and sixty bovine permanent mandibular incisors freshly extracted were used as a substitute for human teeth. The materials tested in this study included 6 universal adhesives, and 2 self-etch adhesives as control. The teeth were assigned into 2 groups: In the first group, etching was performed using 37% phosphoric acid for 30 seconds. In the second group, no pretreatment agent was applied. After adhesive application, a nanohybrid composite resin was inserted into the enamel surface by packing the material into cylindrical-shaped plastic matrices. After storing, the specimens were placed in a universal testing machine. The normality of the data was calculated using the Kolmogorov-Smirnov test. Analysis of variance (ANOVA) was applied to determine whether significant differences in debond strength values existed among the various groups. Groups with phosphoric acid pretreatment showed significantly higher shear bond strength values than groups with no enamel pretreatment (p<0.001). No significant variation in shear strength values was detected when comparing the different adhesive systems applied onto enamel after orthophosphoric acid application (p>0.05). All adhesives provide similar bond strength values when enamel pretreatment is applied even if compositions are different. Bond strength values are lower than promised by manufacturers.

  12. Effect of confinement on bond strength of hot-dip galvanized lap splices in concrete structures

    International Nuclear Information System (INIS)

    Fakhran, Mazen

    2004-01-01

    Galvanizing the reinforcing steel is one of the methods used to protect bars against corrosion. Galvanizing is a hot dip process where the reinforcing bars are immersed in an aqueous pre flux solution of zinc ammonium chloride at a controlled temperature between 840 and 850 degrees F. In 2001, a research program was started at AUB to evaluate experimentally the effect of hot dip galvanizing on the bond capacity of tension lap splices anchored in full-scale beam specimens designed to fail in bond splitting mode. The test results indicated that the use of galvanized bars had a negligible effect on bond strength of reinforcement in normal strength. However, galvanizing caused an average of 20 percent decrease in bond strength of reinforcement in high strength concrete. The primary objective of research reported in this thesis, is the need to find a solution to eliminate the bond reduction of galvanized bars in high strength concrete. It is significant to evaluate the positive effect of the addition of transverse reinforcement in the splice region. The hypothesis to be tested is that such transverse reinforcement will insure uniform bond stress distribution over the entire splice region, thus mobilizing all bar lugs along the splice in the stress transfer mechanism between the bar and the surrounding concrete. Such mechanism might reduce the significant decrease in bond strength in high strength concrete due to galvanizing. To achieve this objective, eighteen full-scale beam specimens were tested in positive bending. Each beam was reinforced with bars spliced in a constant moment region at midspam. The splice length was chosen in such a way that the beams failed in bond splitting of the concrete cover in the splice region. The main variables were type of coating (black or galvanized bars), bar size (20, 25 and 32 mm), and amount of transverse reinforcement in the splice region (0, 2 or 4 stirrups). The test results indicated that confinement did not have a significant

  13. Effect of annealing procedure on the bonding of ceramic to cobalt-chromium alloys fabricated by rapid prototyping.

    Science.gov (United States)

    Tulga, Ayca

    2018-04-01

    An annealing procedure is a heat treatment process to improve the mechanical properties of cobalt-chromium (Co-Cr) alloys. However, information is lacking about the effect of the annealing process on the bonding ability of ceramic to Co-Cr alloys fabricated by rapid prototyping. The purpose of this in vitro study was to evaluate the effects of the fabrication techniques and the annealing procedure on the shear bond strength of ceramic to Co-Cr alloys fabricated by different techniques. Ninety-six cylindrical specimens (10-mm diameter, 10-mm height) made of Co-Cr alloy were prepared by casting (C), milling (M), direct process powder-bed (LaserCUSING) with and without annealing (CL+, CL), and direct metal laser sintering (DMLS) with annealing (EL+) and without annealing (EL). After the application of ceramic to the metal specimens, the metal-ceramic bond strength was assessed using a shear force test at a crosshead speed of 0.5 mm/min. Shear bond strength values were statistically analyzed by 1-way ANOVA and Tukey multiple comparison tests (α=.05). Although statistically significant differences were found among the 3 groups (M, 29.87 ±2.06; EL, 38.92 ±2.04; and CL+, 40.93 ±2.21; P=.002), no significant differences were found among the others (P>.05). The debonding surfaces of all specimens exhibited mixed failure mode. These results showed that the direct process powder-bed method is promising in terms of metal-ceramic bonding ability. The manufacturing technique of Co-Cr alloys and the annealing process influence metal-ceramic bonding. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. Effects of bond primers on bending strength and bonding of glass fibers in fiber-embedded maxillofacial silicone prostheses.

    Science.gov (United States)

    Hatamleh, Muhanad M; Watts, David C

    2011-02-01

    To evaluate the effect of three commonly used bond primers on the bending strength of glass fibers and their bond strength to maxillofacial silicone elastomer after 360 hours of accelerated daylight aging. Eighty specimens were fabricated by embedding resin-impregnated fiber bundles (1.5-mm diameter, 20-mm long) into maxillofacial silicone elastomer M511 (Cosmesil). Twenty fiber bundles served as control and did not receive surface treatment with primers, whereas the remaining 60 fibers were treated with three primers (n = 20): G611 (Principality Medical), A-304 (Factor II), and A-330-Gold (Factor II). Forty specimens were dry stored at room temperature (23 ± 1°C) for 24 hours, and the remaining specimens were aged using an environmental chamber under accelerated exposure to artificial daylight for 360 hours. The aging cycle included continuous exposure to quartz-filtered visible daylight (irradiance 760 W/m(2) ) under an alternating weathering cycle (wet for 18 minutes, dry for 102 minutes). Pull-out tests were performed to evaluate bond strength between fiber bundles and silicone using a universal testing machine at 1 mm/min crosshead speed. A 3-point bending test was performed to evaluate the bending strength of the fiber bundles. One-way Analysis of Variance (ANOVA), Bonferroni post hoc test, and an independent t-test were carried out to detect statistical significances (p accelerated daylight aging. Treatment with primer and accelerated daylight aging increased bending strength of glass fibers. © 2011 by The American College of Prosthodontists.

  15. Fibre-matrix bond strength studies of glass, ceramic, and metal matrix composites

    Science.gov (United States)

    Grande, D. H.; Mandell, J. F.; Hong, K. C. C.

    1988-01-01

    An indentation test technique for compressively loading the ends of individual fibers to produce debonding has been applied to metal, glass, and glass-ceramic matrix composites; bond strength values at debond initiation are calculated using a finite-element model. Results are correlated with composite longitudinal and interlaminar shear behavior for carbon and Nicalon fiber-reinforced glasses and glass-ceramics including the effects of matrix modifications, processing conditions, and high-temperature oxidation embrittlement. The data indicate that significant bonding to improve off-axis and shear properties can be tolerated before the longitudinal behavior becomes brittle. Residual stress and other mechanical bonding effects are important, but improved analyses and multiaxial interfacial failure criteria are needed to adequately interpret bond strength data in terms of composite performance.

  16. Bond Strength Mechanism of Fly Ash Based Geopolymer Mortars: A Review

    Science.gov (United States)

    Zailani, W. W. A.; Abdullah, M. M. A. B.; Razak, R. A.; Zainol, M. R. R. M. A.; Tahir, M. F. M.

    2017-11-01

    Geopolymer possess many excellent properties such as high compressive and bond strength, long term durability, better acid resistance and also known as a “Sustainable Material” due to its low carbon emission and low energy consumption. Thus, it is a good opportunity to develop and explore not only for cement and concrete but also as geopolymeric repair materials. This reviews showed that good bonding properties between geopolymeric repair material and concrete substrate is important in order to acquire an enhanced resistance against penetration of harmful substances and avoiding respalling of the repair material by understanding the bonding behaviour. Bond strength depends to the properties of the repair materials itself and also the surface preparations of concrete substrate.

  17. Electrophoretic Deposition for the Fabrication of High-Performance Metal-Ceramic Hybrid Cladding

    International Nuclear Information System (INIS)

    Park, Junghwan; Jung, Yangil; Park, Dongjun; Kim, Hyungil; Park, Jeongyong; Koo, Yanghyun

    2014-01-01

    Metal-ceramic hybrid cladding consisting of a Zr liner and SiC f /SiC composite is one of the candidate systems. To achieve a high-performance metal-ceramic hybrid cladding, it is important to synthesize the SiC f /SiC composites with high flexural strength. The most common interphases, such as pyrolytic carbon (PyC) and boron nitride (BN) coating, have been applied on the surface of SiC fibers by chemical vapor deposition (CVD) or chemical vapor infiltration (CVI). In addition, the SiC matrix phase for SiC f /SiC composites has been commonly formed by CVI and polymer infiltration and pyrolysis (PIP), which are very costly and complicated processes. For this reason, the fabrication process of SiC f /SiC composites that is low-cost and simple has been strongly needed. In this study, weak phase coating using a commercial colloidal carbon black suspension was performed on SiC fibers through electrophoretic deposition (EPD), and carbon-coated SiC f /SiC composites were fabricated by EPD. The mechanical properties at room temperature were evaluated to investigate the effect of the carbon interfacial layer on the mechanical properties of carbon-coated SiC f /SiC composites. In this study, it was concluded that the EPD method is effective for homogeneous carbon black coating on SiC fibers, and that the carbon coating layer on SiC fibers plays an important role in optimizing the interface between fibers and the matrix, and enhances the toughness of carbon-coated SiC f /SiC composites during fracture

  18. Electrophoretic Deposition for the Fabrication of High-Performance Metal-Ceramic Hybrid Cladding

    Energy Technology Data Exchange (ETDEWEB)

    Park, Junghwan; Jung, Yangil; Park, Dongjun; Kim, Hyungil; Park, Jeongyong; Koo, Yanghyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Metal-ceramic hybrid cladding consisting of a Zr liner and SiC{sub f}/SiC composite is one of the candidate systems. To achieve a high-performance metal-ceramic hybrid cladding, it is important to synthesize the SiC{sub f}/SiC composites with high flexural strength. The most common interphases, such as pyrolytic carbon (PyC) and boron nitride (BN) coating, have been applied on the surface of SiC fibers by chemical vapor deposition (CVD) or chemical vapor infiltration (CVI). In addition, the SiC matrix phase for SiC{sub f}/SiC composites has been commonly formed by CVI and polymer infiltration and pyrolysis (PIP), which are very costly and complicated processes. For this reason, the fabrication process of SiC{sub f}/SiC composites that is low-cost and simple has been strongly needed. In this study, weak phase coating using a commercial colloidal carbon black suspension was performed on SiC fibers through electrophoretic deposition (EPD), and carbon-coated SiC{sub f}/SiC composites were fabricated by EPD. The mechanical properties at room temperature were evaluated to investigate the effect of the carbon interfacial layer on the mechanical properties of carbon-coated SiC{sub f}/SiC composites. In this study, it was concluded that the EPD method is effective for homogeneous carbon black coating on SiC fibers, and that the carbon coating layer on SiC fibers plays an important role in optimizing the interface between fibers and the matrix, and enhances the toughness of carbon-coated SiC{sub f}/SiC composites during fracture.

  19. Hydrogen bond strengths in phosphorylated and sulfated amino acid residues.

    Directory of Open Access Journals (Sweden)

    Chaya Rapp

    Full Text Available Post-translational modification by the addition of an oxoanion functional group, usually a phosphate group and less commonly a sulfate group, leads to diverse structural and functional consequences in protein systems. Building upon previous studies of the phosphoserine residue (pSer, we address the distinct nature of hydrogen bonding interactions in phosphotyrosine (pTyr and sulfotyrosine (sTyr residues. We derive partial charges for these modified residues and then study them in the context of molecular dynamics simulation of model tripeptides and sulfated protein complexes, potentials of mean force for interacting residue pairs, and a survey of the interactions of modified residues among experimental protein structures. Overall, our findings show that for pTyr, bidentate interactions with Arg are particularly dominant, as has been previously demonstrated for pSer. sTyr interactions with Arg are significantly weaker, even as compared to the same interactions made by the Glu residue. Our work sheds light on the distinct nature of these modified tyrosine residues, and provides a physical-chemical foundation for future studies with the goal of understanding their roles in systems of biological interest.

  20. Effect of grape seed extract against biodegradation of composite resin-dentin shear bond strength

    Science.gov (United States)

    Generosa, D. M.; Suprastiwi, E.; Asrianti, D.

    2017-08-01

    This study aimed to analyze the effect of grape seed extract (GSE) on resin-dentin shear bond strength. A group of 48 dentin samples were divided into 6 groups. The six groups, each with eight specimens, included group 1 (control), group 2 (control + NaOCl 10%), group 3 (2.9% GSE application before etching), group 4 (2.9% GSE application before etching + NaOCl 10%), group 5 (2.9% GSE application after etching), and group 6 (2.9% GSE application after etching + NaOCl 10%). Shear bond strengths were measured using a universal testing machine. Statistical analysis was done with the Kruskal-Wallis test and the Mann-Whitney U test. The highest median value was in group 3, and the lowest value was in group 5. GSE can improve the shear bond strength (p = 0.002 and 0.001), but it has no effect on reducing biodegradation (p = 0.141).

  1. Improving the Bond Strength of Rice Husk Ash Concrete by Incorporating Polymer: A New Approach

    Directory of Open Access Journals (Sweden)

    D. K. Bangwar

    2018-02-01

    Full Text Available This paper gives an insight of how to improve the bond strength of cement in which concrete is replaced with rice husk ash. A concrete mix was prepared and was used in different types of mixes i.e. Control Mix, 10% cement substituted concrete with rice husk ash and polymer modified concrete by incorporation different dosages of polymer in the 10% cement substituted concrete. A bar of 12mm diameter, 300mm in length was placed in the center of the cylindrical specimens for pull out test. It was observed that the bond strength between concrete and steel decreases with the replacement of cement with ash, conversely the bond strength improves with the addition of polymer dosages.

  2. Behavior of bonded and unbonded prestressed normal and high strength concrete beams

    Directory of Open Access Journals (Sweden)

    O.F. Hussien

    2012-12-01

    This paper presents an experimental program conducted to study the behavior of bonded and unbounded prestressed normal strength (NSC and high strength concrete (HSC beams. The program consists of a total of nine beams; two specimens were reinforced with non-prestressed reinforcement, four specimens were reinforced with bonded tendons, and the remaining three specimens were reinforced with unbonded tendons. The overall dimensions of the beams are 160 × 340 × 4400-mm. The beams were tested under cyclic loading up to failure to examine its flexural behavior. The main variables in this experimental program are nominal concrete compressive strength (43, 72 and 97 MPa, bonded and unbonded tendons and prestressing index (0%, 70% and 100%. Theoretical analysis using rational approach was also carried out to predict the flexural behavior of the specimens. Evaluation of the analytical work is introduced and compared to the results of the experimental work.

  3. Dentin-composite bond strength measurement using the Brazilian disk test.

    Science.gov (United States)

    Carrera, Carola A; Chen, Yung-Chung; Li, Yuping; Rudney, Joel; Aparicio, Conrado; Fok, Alex

    2016-09-01

    This study presents a variant of the Brazilian disk test (BDT) for assessing the bond strength between composite resins and dentin. Dentin-composite disks (ϕ 5mm×2mm) were prepared using either Z100 or Z250 (3M ESPE) in combination with one of three adhesives, Adper Easy Bond (EB), Adper Scotchbond Multi-Purpose (MP) and Adper Single Bond (SB), and tested under diametral compression. Acoustic emission (AE) and digital image correlation (DIC) were used to monitor debonding of the composite from the dentin ring. A finite element (FE) model was created to calculate the bond strengths using the failure loads. Fracture modes were examined by scanning electron microscopy (SEM). Most specimens fractured along the dentin-resin composite interface. DIC and AE confirmed interfacial debonding immediately before fracture of the dentin ring. Results showed that the mean bond strength with EB (14.9±1.9MPa) was significantly higher than with MP (13.2±2.4MPa) or SB (12.9±3.0MPa) (p0.05). Z100 (14.5±2.3MPa) showed higher bond strength than Z250 (12.7±2.5MPa) (pstrength between dentin and composite, with zero premature failure, reduced variability in the measurements, and consistent failure at the dentin-composite interface. The new test could help to predict the clinical performance of adhesive systems more effectively and consistently by reducing the coefficient of variation in the measured bond strength. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Dentin-Composite Bond Strength Measurement Using the Brazilian Disk Test

    Science.gov (United States)

    Carrera, Carola A.; Chen, Yung-Chung; Li, Yuping; Rudney, Joel; Aparicio, Conrado; Fok, Alex

    2016-01-01

    Objectives This study presents a variant of the Brazilian disk test (BDT) for assessing the bond strength between composite resins and dentin. Methods Dentin-composite disks (φ 5 mm × 2 mm) were prepared using either Z100 or Z250 (3M ESPE) in combination with one of three adhesives, Adper Easy Bond (EB), Adper Scotchbond Multi-Purpose (MP) and Adper Single Bond (SB), and tested under diametral compression. Acoustic emission (AE) and digital image correlation (DIC) were used to monitor debonding of the composite from the dentin ring. A finite element (FE) model was created to calculate the bond strengths using the failure loads. Fracture modes were examined by scanning electron microscopy (SEM). Results Most specimens fractured along the dentin-resin composite interface. DIC and AE confirmed interfacial debonding immediately before fracture of the dentin ring. Results showed that the mean bond strength with EB (14.9±1.9 MPa) was significantly higher than with MP (13.2±2.4 MPa) or SB (12.9±3.0 MPa) (p0.05). Z100 (14.5±2.3 MPa) showed higher bond strength than Z250 (12.7±2.5 MPa) (padhesive failure mode. EB failed mostly at the dentin-adhesive interface, whereas MP at the composite-adhesive interface; specimens with SB failed at the composite-adhesive interface and cohesively in the adhesive. Conclusions The BDT variant showed to be a suitable alternative for measuring the bond strength between dentin and composite, with zero premature failure, reduced variability in the measurements, and consistent failure at the dentin-composite interface. PMID:27395367

  5. Influence of bleaching and desensitizing gel on bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Fernanda Alves Rodrigues Britto

    2015-04-01

    Full Text Available OBJECTIVE: The objective of this study was to assess, in vitro, the influence of bleaching gel and the use of desensitizing agent over bond strength of ceramic brackets bonded to bovine enamel. METHODS: One hundred bovine incisors were selected and randomly divided into five groups (n = 20: Group 1, control group (without bleaching; Group 2, bleached with 35% hydrogen peroxide; Group 3, bleached with 35% hydrogen peroxide (three applications, 15 minutes each and desensitizing agent applied for 10 minutes; Group 4, bleached with 35% hydrogen peroxide for 40 minutes; Group 5, bleached with 35% hydrogen peroxide for 40 minutes with desensitizing agent applied for 10 minutes. Brackets were bonded 7 days after bleaching and submitted to shear bond strength test after 24 hours at a compression rate of 1 mm/minute. After fracture, the adhesive remnant index (ARI was assessed under stereoscopic at 40 x magnification. Shear strength data (MPa were submitted to one-way ANOVA and Tukey's test with significance level set at 5%. RESULTS: Group 5 (29.33 MPa showed significantly higher bond strength than Group 1 (19.19 MPa, Group 2 (20.59 MPa and Group 4 (23.25 MPa, but with no difference in comparison to Group 3. There was no significant difference among the other groups. The adhesive remnant index showed predominance of score 3, that is, all resin remained adhered to enamel for all groups. CONCLUSION: Bleaching with 35% hydrogen peroxide with calcium associated with desensitizing agent application produced higher bond strength values of brackets bonded to bovine enamel.

  6. Comparative study to evaluate shear bond strength of RMGIC to composite resin using different adhesive systems

    Directory of Open Access Journals (Sweden)

    Manoj G Chandak

    2012-01-01

    Full Text Available Aim: The aim of the study is to compare and evaluate the role of new dental adhesives to bond composite to the resinmodified glass inomer cement (RMGIC. Materials and Methods: Thirty specimens were prepared on acrylic blocks, with wells prepared in it by drilling holes, to retain the RMGIC. The specimens were randomly divided into three groups of ten specimens each. In Group a thin layer of selfetch adhesive (3M ESPE was applied between the RMGIC and the composite resin FILTEK P60 (3M SPE. In Group II, total etch adhesive (Adeper Scotch bond 2, 3M ESPE was applied, and in Group III, there was no application of any adhesive between RMGIC and the composite resin. After curing all the specimens, the shear bond strength was measured using an Instron universal testing machine. Results: The results were drawn and tabulated using ANOVA-fishers and Dunnet D statistical tests.The maximum shear bond strength values were recorded in Group I specimens with self-etch adhesive showing a mean value of 2.74 when compared to the Group II adhesive (Total etch showing a mean shear strength of value 1.89, where no adhesive was used, showed a minimum mean shear bond strength of 1.42. There was a great and significant difference between Group I and Group II (P value 0.05 whereas, both Group I and Group II showed a vast and significant difference from Group III (P value = 0-001. Conclusion: Hence, this present study concludes that application of self-etch adhesive (3M ESPE, U.S.A in between RMGIC and composite resin increases the shear bond strength between RMGIC and the resin composites, as compared to the total-etch type adhesive (Adeper Scotch bond 2,3M ESPE, U.S.A as well as without application of the adhesive agent.

  7. Microtensile Bond Strength and Micromorphology of Bur-cut Enamel Using Five Adhesive Systems.

    Science.gov (United States)

    Vinagre, Alexandra; Ramos, João; Messias, Ana; Marques, Fernando; Caramelo, Francisco; Mata, António

    2015-04-01

    This study compared the microtensile bond strengths (μTBS) of two etch-and-rinse (ER) (OptiBond FL [OBFL]; Prime & Bond NT [PBNT]) and three self-etching (SE) (Clearfil SE Bond [CSEB]; Xeno III [XIII]; Xeno V+ [XV+]) adhesives systems to bur-prepared human enamel considering active (AA) and passive (PA) application of the self-etching systems. Ninety-six enamel surfaces were prepared with a medium-grit diamond bur and randomly allocated into 8 groups to receive adhesive restorations: G1: OBFL; G2: PBNT; G3: CSEB/PA; G4: CSEB/ AA; G5: XIII/PA; G6: XIII/AA; G7: XV+/PA; G8: XV+/AA. After composite buildup, samples were sectioned to obtain a total of 279 bonded sticks (1 mm2) that were submitted to microtensile testing (μTBS; 0.5 mm/min) after 24-h water storage (37°C). Etching patterns and adhesive interfacial ultramorphology were also evaluated with confocal laser scanning (CLSM) and scanning electron microscopy (SEM). Data was analyzed with one-way ANOVA (α = 0.05). Weibull probabilistic distribution was also determined. Regarding μTBS, both adhesive system and application mode yielded statistically significant differences (p systems together with CSEB/AA and XIII/PA recorded the highest and statistically similar bond strength results. XV+ presented very low bond strength values, regardless of the application mode. Among self-etching adhesives, CSEB produced significantly higher μTBS values when applied actively. Qualitative evaluation by SEM and CLSM revealed substantial differences between groups both in adhesive interfaces and enamel conditioning patterns. ER and SE adhesive systems presented distinctive bond strengths to bur-cut enamel. The application mode effect was adhesive dependent. Active application improved etching patterns and resin interfaces micromorphology.

  8. Repair bond strength of composite resin to sandblasted and laser irradiated Y-TZP ceramic surfaces.

    Science.gov (United States)

    Kirmali, Omer; Barutcigil, Çağatay; Ozarslan, Mehmet Mustafa; Barutcigil, Kubilay; Harorlı, Osman Tolga

    2015-01-01

    This study investigated the effects of different surface treatments on the repair bond strength of yttrium-stabilized tetragonal zirconia polycrystalline ceramic (Y-TZP) zirconia to a composite resin. Sixty Y-TZP zirconia specimens were prepared and randomly divided into six groups (n = 10) as follows: Group 1, surface grinding with Cimara grinding bur (control); Group 2, sandblasted with 30 µm silica-coated alumina particles; Group 3, Nd:YAG laser irradiation; Group 4, Er,Cr:YSGG laser irradiation; Group 5, sandblasted + Nd:YAG laser irradiation; and Group 6, sandblasted + Er,Cr:YSGG laser irradiation. After surface treatments, the Cimara(®) System was selected for the repair method and applied to all specimens. A composite resin was built-up on each zirconia surface using a cylindrical mold (5 × 3 mm) and incrementally filled. The repair bond strength was measured with a universal test machine. Data were analyzed using a one-way ANOVA and a Tukey HSD test (p = 0.05). Surface topography after treatments were evaluated by a scanning electron microscope (SEM). Shear bond strength mean values ranged from 15.896 to 18.875 MPa. There was a statistically significant difference between group 3 and the control group (p < 0.05). Also, a significant increase in bond strength values was noted in group 6 (p < 0.05). All surface treatment methods enhanced the repair bond strength of the composite to zirconia; however, there were no significant differences between treatment methods. The results revealed that Nd:YAG laser irradiation along with the combination of sandblasting and Er,Cr:YSGG laser irradiation provided a significant increase in bond strength between the zirconia and composite resin. © Wiley Periodicals, Inc.

  9. Relining effects on the push-out shear bond strength of glass fiber posts

    Directory of Open Access Journals (Sweden)

    Adriana Rosado Valente ANDRIOLI

    Full Text Available Abstract Introduction The correct use of glass fiber posts in endodontically treated teeth is essential for the clinical success of restorative treatment. Objective This study evaluated the push-out shear bond strength of relined (R or non-relined (NR glass fiber posts, cemented with self-adhesive resin cement [RelyXTM U100 (U100] and conventional resin cement [RelyXTM ARC (ARC]. Material and method Sixty human single-rooted teeth were endodontically treated and divided into ARC-NR; U100-NR; ARC-R; U100-R groups. The teeth were sectioned into cervical, middle and apical thirds, and subjected to the push-out test. Bond strength was analyzed by the Friedman test; cement and post types were compared by the Mann Whitney test. The pattern of failures was evaluated with digital camera through images at 200x magnification, and was classified as adhesive (at the cement/dentin or cement/post interface, cohesive (cement or post, and mixed failures. Result In ARC-NR, bond strength values were higher in the cervical third; in U100-NR and ARC-R they were similar between the thirds. In U100-R, in the cervical and middle thirds the bond strength values were similar, and there was lower value in the apical third. For non-relined glass fiber posts, the highest mean bond strength values were observed with self-adhesive resin cement. Whereas, relined posts cemented with conventional resin cement had stronger cement layer in comparison with non-relined fiber posts. Conclusion The post relining technique was efficient in ARC-R. ARC-NR and U100-R showed improved bond strength in the cervical region of canal walls. The main failures were adhesive at the cement-post interface.

  10. Computational study of the signature of hydrogen-bond strength on the infrared spectra of a hydrogen-bonded complex dissolved in a polar liquid

    International Nuclear Information System (INIS)

    Hanna, Gabriel; Geva, Eitan

    2010-01-01

    The signature of hydrogen-bond strength on the one- and two-dimensional infrared spectra of the hydrogen-stretch in a hydrogen-bonded complex dissolved in a polar liquid was investigated via mixed quantum-classical molecular dynamics simulations. Non-Condon effects were found to intensify with increasing hydrogen-bond strength and to shift oscillator strength from the stable configurations that correspond to the ionic and covalent tautomers into unstable configurations that correspond to the transition-state between them. The transition-state peak is observed to blue shift and increase in intensity with increasing hydrogen-bond strength, and to dominate the spectra in the case of a strong hydrogen-bond. It is argued that the application of multidimensional infrared spectroscopy in the region of the transition-state peak can provide a uniquely direct probe of the molecular events underlying breaking and forming of hydrogen-bonds in the condensed phase.

  11. Influence of Different Etching Modes on Bond Strength to Enamel using Universal Adhesive Systems.

    Science.gov (United States)

    Diniz, Ana Cs; Bandeca, Matheus C; Pinheiro, Larissa M; Dos Santosh Almeida, Lauber J; Torres, Carlos Rg; Borges, Alvaro H; Pinto, Shelon Cs; Tonetto, Mateus R; De Jesus Tavarez, Rudys R; Firoozmand, Leily M

    2016-10-01

    The adhesive systems and the techniques currently used are designed to provide a more effective adhesion with reduction of the protocol application. The objective of this study was to evaluate the bond strength of universal adhesive systems on enamel in different etching modes (self-etch and total etch). The mesial and distal halves of 52 bovine incisors, healthy, freshly extracted, were used and divided into seven experimental groups (n = 13). The enamel was treated in accordance with the following experimental conditions: FUE-Universal System - Futurabond U (VOCO) with etching; FUWE - Futurabond U (VOCO) without etching; SB-Total Etch System - Single Bond 2 (3M); SBUE-Universal System - Single Bond Universal (3M ESPE) with etching; SBUWE - Single Bond Universal (3M ESPE) without etching; CLE-Self-etch System - Clearfil SE Bond (Kuraray) was applied with etching; CLWE - Clearfil SE Bond (Kuraray) without etching. The specimens were made using the composite spectrum TPH (Dentsply) and stored in distilled water (37 ± 1°C) for 1 month. The microshear test was performed using the universal testing machine EMIC DL 2000 with the crosshead speed of 0.5 mm/minute. The bond strength values were analyzed using statistical tests (Kruskal-Wallis test and Mann-Whitney test) with Bonferroni correction. There was no statistically significant difference between groups (p adhesive interface revealed that most failures occurred between the interface composite resin and adhesive. The universal adhesive system used in dental enamel varies according to the trademark, and the previous enamel etching for universal systems and the self-etch both induced greater bond strength values. Selective enamel etching prior to the application of a universal adhesive system is a relevant strategy for better performance bonding.

  12. Residual Tensile Strength and Bond Properties of GFRP Bars after Exposure to Elevated Temperatures

    Directory of Open Access Journals (Sweden)

    Devon S. Ellis

    2018-02-01

    Full Text Available The use of fiber reinforced polymer (FRP bars in reinforced concrete members enhances corrosion resistance when compared to traditional steel reinforcing bars. Although there is ample research available on the behavior of FRP bars and concrete members reinforced with FRP bars under elevated temperatures (due to fire, there is little published information available on their post-fire residual load capacity. This paper reports residual tensile strength, modulus of elasticity, and bond strength (to concrete of glass fiber reinforced polymer (GFRP bars after exposure to elevated temperatures of up to 400 °C and subsequent cooling to an ambient temperature. The results showed that the residual strength generally decreases with increasing temperature exposure. However, as much as 83% of the original tensile strength and 27% of the original bond strength was retained after the specimens were heated to 400 °C and then cooled to ambient temperature. The residual bond strength is a critical parameter in post-fire strength assessments of GFRP-reinforced concrete members.

  13. Residual Tensile Strength and Bond Properties of GFRP Bars after Exposure to Elevated Temperatures.

    Science.gov (United States)

    Ellis, Devon S; Tabatabai, Habib; Nabizadeh, Azam

    2018-02-27

    The use of fiber reinforced polymer (FRP) bars in reinforced concrete members enhances corrosion resistance when compared to traditional steel reinforcing bars. Although there is ample research available on the behavior of FRP bars and concrete members reinforced with FRP bars under elevated temperatures (due to fire), there is little published information available on their post-fire residual load capacity. This paper reports residual tensile strength, modulus of elasticity, and bond strength (to concrete) of glass fiber reinforced polymer (GFRP) bars after exposure to elevated temperatures of up to 400 °C and subsequent cooling to an ambient temperature. The results showed that the residual strength generally decreases with increasing temperature exposure. However, as much as 83% of the original tensile strength and 27% of the original bond strength was retained after the specimens were heated to 400 °C and then cooled to ambient temperature. The residual bond strength is a critical parameter in post-fire strength assessments of GFRP-reinforced concrete members.

  14. The difference of tensile bond strength between total and self etch adhesive systems in dentin

    Directory of Open Access Journals (Sweden)

    Selly Yusalina

    2010-03-01

    Full Text Available Total etch adhesive system has been widely used in teeth conservation area as an adhesive agent before implicating composite resin restoration agent. The aim of this research is to prove the difference of tensile bond strength between total etch (Single Bond and self etch adhesive system (Adper prompt L-Pop on dentin surface in vitro. The extracted and non carries maxillary premolar teeth were used in this research and were divided into 2 groups. The first group comprised 15 specimen teeth etched in phosphoric acid and was applicated with the Single Bond adhesive agent. The second group comprised 15 specimen teeth, applicated with the Adper Prompt-L-Pop. The composite resin (Z 350, 3M was applied incrementally and each of the layers was rayed for 20 seconds. The specimens were stored in physiologic solution before they were tested. Tensile bond strength was measured by LRX Plus Lloyd Instrument, with 1 N load and 1 mm/minute speed, and the measurement result was in Mpa unit. The result was evaluated statistically by the Student t-test with α = 0.05. Single Bond (the 5th generation showed a better bond strength compared to the Adper Prompt-L-Pop (the 6th generation.

  15. Effect of adhesive resin cements on bond strength of ceramic core materials to dentin.

    Science.gov (United States)

    Gundogdu, M; Aladag, L I

    2018-03-01

    The aim of the present study was to evaluate the effects of self-etch and self-adhesive resin cements on the shear bond strength of ceramic core materials bonded to dentin. Extracted, caries-free, human central maxillary incisor teeth were selected, and the vestibule surfaces were cut flat to obtain dentin surfaces. Ceramic core materials (IPS e.max Press and Prettau Zirconia) were luted to the dentin surfaces using three self-etch adhesive systems (Duo-Link, Panavia F 2.0, and RelyX Ultimate Clicker) and two self-adhesive resin systems (RelyX U200 Automix and Maxcem Elite). A shear bond strength test was performed using a universal testing machine. Failure modes were observed under a stereomicroscope, and bonding interfaces between the adhesive resin cements and the teeth were evaluated with a scanning electron microscope. Data were analyzed with Student's t-test and one-way analysis of variance followed by Tukey's test (α = 0.05). The type of adhesive resin cement significantly affected the shear bond strengths of ceramic core materials bonded to dentin (P materials when the specimens were luted with self-adhesive resin cements (P materials.

  16. Bond strength of primer/cement systems to zirconia subjected to artificial aging.

    Science.gov (United States)

    Zhao, Li; Jian, Yu-Tao; Wang, Xiao-Dong; Zhao, Ke

    2016-11-01

    Creating reliable and durable adhesion to the nonactive zirconia surface is difficult and has limited zirconia use. The introduction of functional monomers such as 10-methacryloyloxydecyl dihydrogen phosphate (MDP) appears to have enhanced bond strength to zirconia. The purpose of this in vitro study was to evaluate the long-term bond strength of several MDP-containing primer/cement systems to zirconia. Zirconia blocks were divided into 6 groups (n=24) according to the 3 primers/cements to be bonded, as follows: Scotchbond Universal/RelyX Ultimate (SU/RU; consisting of MDP-containing primer/MDP-free cement); Clearfil ceramic primer/Panavia F (CCP/PAN; consisting ofMDP-containing/MDP-containing); and Z-Prime Plus/Duo-Link (ZP/DUO; consisting ofMDP-containing/MDP-free), which were compared with 3 nonprimed groups, RU, PAN, and DUO. After bonding, each group was further divided into 3 subgroups (n=8) according to the level of aging: 24-hour storage in water at 37°C (24H); 30-day storage at 37°C (30D); and 30-day storage at 37°C followed by 3000 thermal cycles (30D/TC). After aging, a shear bond strength test and failure mode analysis were performed. The data were analyzed using 2-way ANOVA (α=.05). After aging, nearly all primer/cement groups presented significantly higher bond strength than the related nonprimed groups for each level of aging (P<.05), except for CCP/PAN versus PAN with 24H (P=.741). SU/RU had the highest bond strength among the groups for all treatments (P<.05), except for CCP/PAN versus SU/RU with 30D/TC (P=.171). Among the nonprimed groups, only RU went through 30D/TC without premature debonding. With 24H and 30D, the failure modes in SU/RU and CCP/PAN were purely mixed, whereas those in the other groups were mainly adhesive, except for RU. The superiority of the initial bond strength in SU/RU may result from some functional components other than MDP. The presence of MDP in the cement did not appear to have a positive effect on long-term bond

  17. Effect of Pre-heating on Microtensile Bond Strength of Composite Resin to Dentin.

    Directory of Open Access Journals (Sweden)

    Abdolrahim Davari

    2014-10-01

    Full Text Available Direct composite resin restorations are widely used and the impact of different storage temperatures on composites is not well understood. The purpose of this study was to evaluate the microtensile bond strength of composite to dentin after different pre-curing temperatures.Occlusal surfaces of 44 human molars were ground with diamond burs under water coolant and polished with 600 grit silicon carbide papers to obtain flat dentin surfaces. The dentin was etched with 37% phosphoric acid and bonded with Adper Single Bond 2 according to the manufacturer's instructions. The specimens were randomly divided into two groups (n=22 according to the composite resin applied: FiltekP60 and Filtek Z250. Each group included three subgroups of composite resin pre-curing temperatures (4°C, 23°C and 37°C. Composite resins were applied to the dentin surfaces in a plastic mold (8mm in diameter and 4mm in length incrementally and cured. Twenty-two composite-to-dentin hour-glass sticks with one mm(2 cross-sectional area per group were prepared. Microtensile bond strength measurements were made using a universal testing machine at a crosshead speed of one mm/min. For statistical analysis, t-test, one-way and two-way ANOVA were used. The level of significance was set at P<0.05.Filtek P60 pre-heated at 37ºC had significantly higher microtensile bond strength than Filtek Z250 under the same condition. The microtensile bond strengths were not significantly different at 4ºC, 23ºC and 37ºC subgroups of each composite resin group.Filtek P60 and Filtek Z250 did not have significantly different microtensile bond strengths at 4ºC and 23ºC but Filtek P60 had significantly higher microtensile bond strength at 37 ºC. Composite and temperature interactions had significant effects on the bond strength.

  18. Long-term bond strength of adhesive systems applied to etched and deproteinized dentin

    Directory of Open Access Journals (Sweden)

    Ninoshka Uceda-Gómez

    2007-12-01

    Full Text Available The aim of this study was to evaluate the early and 12-month bond strength of two adhesive systems (Single Bond-SB and One Step-OS applied to demineralized dentin (WH and demineralized/NaOCl-treated dentin (H. Twenty flat dentin surfaces were exposed, etched, rinsed and slightly dried. For the H groups, a solution of 10% NaOCl was applied for 60 s, rinsed (15 s and slightly dried. The adhesives were applied according to the manufacturer's instructions and composite resin crowns were incrementally constructed. After 24 h (water-37ºC, the specimens was sectioned in order to obtain resin-dentin sticks (0.8 mm². The specimens were tested in microtensile (0.5 mm/min immediately (IM or after 12 months of water storage (12M. The data (MPa were subjected to ANOVA and Tukey's test (a=0.05. Only the main factors adhesive and time were significant (p=0.004 and p=0.003, respectively. SB (42.3±9.1 showed higher bond strengths than OS (33.6±11.6. The mean bond strength for IM-group (42.5±8.7 was statistically superior to 12M (33.3±11.8. The use of 10% NaOCl, after acid etching, did not improve the immediate and the long-term resin-dentin bond strength.

  19. Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin

    Directory of Open Access Journals (Sweden)

    Cécile Bernard

    2015-01-01

    Full Text Available The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL and a two-steps/self-etch adhesive system (Optibond XTR were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR. All specimens were submitted to thermocycling ageing (10000 cycles. The specimens were sectioned in 1 mm2 sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL.

  20. Surface topography and bond strengths of feldspathic porcelain prepared using various sandblasting pressures.

    Science.gov (United States)

    Moravej-Salehi, Elham; Moravej-Salehi, Elahe; Valian, Azam

    2016-11-01

    The purpose of this study was to determine the bond strength of composite resin to feldspathic porcelain and its surface topography after sandblasting at different pressures. In this in vitro study, 68 porcelain disks were fabricated and randomly divided into four groups of 17. The porcelain surface in group 1 was etched with hydrofluoric acid. Groups 2, 3, and 4 were sandblasted at 2, 3 and 4 bars pressure, respectively. Surface topography of seven samples in each of the four groups was examined by a scanning electron microscope (SEM). The remaining 40 samples received the same silane agent, bonding agent, and composite resin and they were then subjected to 5000 thermal cycles and evaluated for shear bond strength. Data were analyzed using one-way anova. The mode of failure was determined using stereomicroscope and SEM. The highest shear bond strength was seen in group 4. however, statistically significant differences were not seen between the groups (P = 0.780). The most common mode of failure was cohesive in porcelain. The SEM showed different patterns of hydrofluoric acid etching and sandblasting. Increasing the sandblasting pressure increased the surface roughness of feldspathic porcelain but no difference in bond strength occurred. © 2015 Wiley Publishing Asia Pty Ltd.

  1. Amalgam shear bond strength to dentin using single-bottle primer/adhesive systems.

    Science.gov (United States)

    Cobb, D S; Denehy, G E; Vargas, M A

    1999-10-01

    To evaluate the in vitro shear bond strengths (SBS) of a spherical amalgam alloy (Tytin) to dentin using several single-bottle primer/adhesive systems both alone: Single Bond (SB), OptiBond Solo (Sol), Prime & Bond 2.1 (PB), One-Step (OS) and in combination with the manufacturer's supplemental amalgam bonding agent: Single Bond w/3M RelyX ARC (SBX) and Prime & Bond 2.1 w/Amalgam Bonding Accessory Kit (PBA). Two, three-component adhesive systems, Scotchbond Multi-Purpose (SBMP) and Scotchbond Multi-Purpose Plus w/light curing (S + V) and w/o light curing (S+) were used for comparison. One hundred eight extracted human third molars were mounted lengthwise in phenolic rings with acrylic resin. The proximal surfaces were ground to expose a flat dentin surface, then polished to 600 grit silicon carbide paper. The teeth were randomly assigned to 9 groups (n = 12), and dentin surfaces in each group were treated with an adhesive system according to the manufacturer's instructions, except for S + V specimens, where the adhesive was light cured for 10 s before placing the amalgam. Specimens were then secured in a split Teflon mold, having a 3 mm diameter opening and amalgam was triturated and condensed onto the treated dentin surfaces. Twenty minutes after condensation, the split mold was separated. Specimens were placed in distilled water for 24 hrs, then thermocycled (300 cycles, between 5 degrees C and 55 degrees C, with 12 s dwell time). All specimens were stored in 37 degrees C distilled water for 7 days, prior to shear strength testing using a Zwick Universal Testing Machine at a cross-head speed of 0.5 mm/min. The highest to the lowest mean dentin shear bond strength values (MPa) for the adhesive systems tested were: S + V (10.3 +/- 2.3), SBX (10.2 +/- 3.5), PBA, (6.4 +/- 3.6), SOL (5.8 +/- 2.5), SBMP (5.7 +/- 1.8), S+ (4.8 +/- 2.3), PB (2.7 +/- 2.6), SB (2.7 +/- 1.1) and OS (2.5 +/- 1.8). One-way ANOVA and Duncan's Multiple Range Test indicated significant

  2. Similar strength of the NH⋯O and NH⋯S hydrogen bonds in binary complexes

    DEFF Research Database (Denmark)

    Andersen, Cecilie Lindholm; Jensen, Christine S.; Mackeprang, Kasper

    2014-01-01

    to be extremely small with only 5 and 19 cm-1 for DMA-DME and DMA-DMS, respectively. The experimentally determined integrated absorbance has been combined with a calculated oscillator strength to determine an equilibrium constant of 2 × 10-3 and 4 × 10-3 for the DMA-DME and DMA-DMS complexes, respectively....... The topological analyses reveal that several hydrogen bond interactions are present in the complexes. The calculated binding energies, geometric parameters, observed redshifts, and topological analyses suggest that oxygen and sulfur are hydrogen bond acceptors of similar strength. (Graph Presented)....

  3. Bond Coat Engineering Influence on the Evolution of the Microstructure, Bond Strength, and Failure of TBCs Subjected to Thermal Cycling

    Science.gov (United States)

    Lima, R. S.; Nagy, D.; Marple, B. R.

    2015-01-01

    Different types of thermal spray systems, including HVOF (JP5000 and DJ2600-hybrid), APS (F4-MB and Axial III), and LPPS (Oerlikon Metco system) were employed to spray CoNiCrAlY bond coats (BCs) onto Inconel 625 substrates. The chemical composition of the BC powder was the same in all cases; however, the particle size distribution of the powder employed with each torch was that specifically recommended for the torch. For optimization purposes, these BCs were screened based on initial evaluations of roughness, porosity, residual stress, relative oxidation, and isothermal TGO growth. A single type of standard YSZ top coat was deposited via APS (F4MB) on all the optimized BCs. The TBCs were thermally cycled by employing a furnace cycle test (FCT) (1080 °C-1 h—followed by forced air cooling). Samples were submitted to 10, 100, 400, and 1400 cycles as well as being cycled to failure. The behavior of the microstructures, bond strength values (ASTM 633), and the TGO evolution of these TBCs, were investigated for the as-sprayed and thermally cycled samples. During FCT, the TBCs found to be both the best and poorest performing and had their BCs deposited via HVOF. The results showed that engineering low-oxidized BCs does not necessarily lead to an optimal TBC performance. Moreover, the bond strength values decrease significantly only when the TBC is about to fail (top coat spall off) and the as-sprayed bond strength values cannot be used as an indicator of TBC performance.

  4. Influence of application methods of one-step self-etching adhesives on microtensile bond strength

    OpenAIRE

    Chul-Kyu Choi,; Sung-Ae Son; Jin-Hee Ha; Bock Hur; Hyeon-Cheol Kim; Yong-Hun Kwon; Jeong-Kil Park

    2011-01-01

    Objectives The purpose of this study was to evaluate the effect of various application methods of one-step self-etch adhesives to microtensile resin-dentin bond strength. Materials and Methods Thirty-six extracted human molars were used. The teeth were assigned randomly to twelve groups (n = 15), according to the three different adhesive systems (Clearfil Tri-S Bond, Adper Prompt L-Pop, G-Bond) and application methods. The adhesive systems were applied on the dentin as follows: 1) T...

  5. Effect Of Storage And Disinfection Methods Of Extracted Bovine Teeth On Bond Strength To Dentin

    OpenAIRE

    Humel M.M.C.; Oliveira M.T.; Cavalli V.; Giannini M.

    2007-01-01

    The aim of this study was to evaluate the effect of storage and disinfection methods (SDM) on bond strength (BS) to bovine dentin, using two adhesive systems. Adper Single Bond and Clearfil Protect Bond. Method: Extracted bovine teeth were assigned to the following SDM: 100% Humidity (HU); Gamma Radiation (GR); Autoclave (AU): 0.10g/mL Thymol (TH); 10% Formatin (FO); Frozen (FR); 0.2% Sodium Azide (SA) and 0.5% Chloramine T (CT) (n=10). The GR and AU groups were submitted to sterilization met...

  6. Effect of surface treatment of FRC-Post on bonding strength to resin cements

    Directory of Open Access Journals (Sweden)

    Chan-Hyun Park,

    2011-03-01

    Full Text Available Objectives The purpose of this study was to evaluate the effect of surface treatment of FRC-Post on bonding strength to resin cements. Materials and Methods Pre-surface treated LuxaPost (DMG, Rely-X Fiber Post (3M ESPE and self adhesive resin cement Rely-X Unicem (3M ESPE, conventional resin cement Rely-X ARC (3M ESPE, and Rely-X Ceramic Primer (3M ESPE were used. After completing the surface treatments of the posts, posts and resin cement were placed in clear molds and photo-activation was performed. The specimens were sectioned perpendicular to the FRC-Post into 2 mm-thick segments, and push-out strength were measured. The results of bond strength value were statistically analyzed using independent samples t-test and one-way ANOVA with multiple comparisons using Scheffe's test. Results Silanization of posts affect to the bond strength in LuxaPost, and did not affect in Rely-X Fiber Post. Rely-X ARC showed higher value than Rely-X Unicem. Conclusions Silanization is needed to enhance the bond strength between LuxaPost and resin cements.

  7. Effect of various commercially available mouthrinses on shear bond strength of orthodontic metal brackets: An in vitro study

    Directory of Open Access Journals (Sweden)

    Nazeer Ahmed Meeran

    2013-01-01

    Conclusion: Alcohol containing mouthrinses affect the shear bond strength of the metal orthodontic brackets bonded with composite resin (Transbond XT in the present study, more when compared with alcohol-free mouthrinses. It is, therefore, highly advisable to avoid alcohol containing mouthrinses in patients undergoing orthodontic treatment and use alcohol-free mouthrinses as adjuncts to regular oral hygiene procedures for maintaining good enamel integrity and periodontal health, without compromising the shear bond strength of the bonded metal brackets.

  8. A comparative evaluation of the shear bond strength of five different orthodontic bonding agents polymerized using halogen and light-emitting diode curing lights: An in vitro investigation

    Directory of Open Access Journals (Sweden)

    Sujoy Banerjee

    2011-01-01

    Full Text Available Purpose: With the introduction of photosensitive (light-activated restorative materials in orthodontics, various methods have been suggested to enhance the polymerization of the materials used, including use of more powerful light curing devices. Bond strength is an important property and determines the amount of force delivered and the treatment duration. Many light-cured bonding materials have become popular but it is the need of the hour to determine the bonding agent that is the most efficient and has the desired bond strength. Aim: To evaluate and compare the shear bond strengths of five different orthodontic light cure bonding materials cured with traditional halogen light and low-intensity light-emitting diode (LED light curing unit. Materials and Methods: 100 human maxillary premolar teeth, extracted for orthodontic purpose, were used to prepare the samples. 100 maxillary stainless steel bicuspid brackets of 0.018 slot of Roth prescription, manufactured by D-tech Company, were bonded to the prepared tooth surfaces of the mounted samples using five different orthodontic bracket bonding light-cured materials, namely, Enlight, Fuji Ortho LC (resin-modified glass ionomer cement, Orthobond LC, Relybond, and Transbond XT. The bond strength was tested on an Instron Universal testing machine (model no. 5582. Results: In Group 1 (halogen group, Enlight showed the highest shear bond strength (16.4 MPa and Fuji Ortho LC showed the least bond strength (6.59 MPa (P value 0.000. In Group 2 (LED group, Transbond showed the highest mean shear bond strength (14.6 MPa and Orthobond LC showed the least mean shear bond strength (6.27 MPa (P value 0.000. There was no statistically significant difference in the shear bond strength values of all samples cured using either halogen (mean 11.49 MPa or LED (mean 11.20 MPa, as the P value was 0.713. Conclusion: Polymerization with both halogen and LED resulted in shear bond strength values which were above the

  9. Shear strength of a thermal barrier coating parallel to the bond coat

    International Nuclear Information System (INIS)

    Cruse, T.A.; Dommarco, R.C.; Bastias, P.C.

    1998-01-01

    The static and low cycle fatigue strength of an air plasma sprayed (APS) partially stabilized zirconia thermal barrier coating (TBC) is experimentally evaluated. The shear testing utilized the Iosipescu shear test arrangement. Testing was performed parallel to the TBC-substrate interface. The TBC testing required an innovative use of steel extensions with the TBC bonded between the steel extensions to form the standard Iosipescu specimen shape. The test method appears to have been successful. Fracture of the TBC was initiated in shear, although unconstrained specimen fractures propagated at the TBC-bond coat interface. The use of side grooves on the TBC was successful in keeping the failure in the gage section and did not appear to affect the shear strength values that were measured. Low cycle fatigue failures were obtained at high stress levels approaching the ultimate strength of the TBC. The static and fatigue strengths do not appear to be markedly different from tensile properties for comparable TBC material

  10. Influence of ultraviolet irradiation treatment on porcelain bond strength of titanium surfaces.

    Science.gov (United States)

    Kumasaka, Tomonari; Ohno, Akinori; Hori, Norio; Hoshi, Noriyuki; Maruo, Katsuichiro; Kuwabara, Atsushi; Seimiya, Kazuhide; Toyoda, Minoru; Kimoto, Katsuhiko

    2018-01-26

    To determine the effect of titanium (Ti) surface modification by ultraviolet irradiation (UVI) on the bond strength between Ti and porcelain. Grade 2 Ti plates were allotted to five groups: sandblasted (SA), 15 min UVI (UV), SA+5 min UVI (SA+UV5), SA+10 min UVI (SA+UV10), and SA+15 min UVI (SA+UV15). After surface treatment, porcelain was added. A precious metal (MC) was used for comparison with Ti. The effects of 24-h storage at room temperature versus thermal cycling only at 5 and 55°C in water were evaluated. Subsequently, the tensile strength of each sample was tested. Data were analyzed using one-way analysis of variance and the Tukey test. In both the room temperature and thermal cycling groups, the MC and SA+15 min UVI samples showed significantly greater bond strengths than the other samples (pbond strength between porcelain and the Ti surface.

  11. Influence of blood contamination during multimode adhesive application on the microtensile bond strength to dentin.

    Science.gov (United States)

    Kucukyilmaz, E; Celik, E U; Akcay, M; Yasa, B

    2017-12-01

    The present study evaluated the effects of blood contamination performed at different steps of bonding on the microtensile bond strength (μTBS) of multimode adhesives to dentin when using the self-etch approach. Seventy-five molars were randomly assigned to three adhesive groups comprising 25 specimens each: two multimode adhesives [Single Bond Universal (SBU) and All-Bond Universal (ABU)] and a conventional one-step self-etch adhesive [Clearfil S3 Bond Plus (CSBP)]. Each group was subdivided as follows: (1) uncontaminated (control): bonding application/light curing as a positive control; (2) contamination-1 (cont-1): bonding application/light curing/blood contamination/dry as a negative control; (3) contamination-2 (cont-2): bonding application/light curing/blood contamination/rinse/dry; (4) contamination-3 (cont-3): bonding application/blood contamination/dry/bonding re-application/light curing; and (5) contamination-4 (cont-4): bonding application/blood contamination/rinse/dry/bonding re-application/light curing. Dentin specimens were prepared for μTBS testing after the composite resin application. Data were analyzed with two-way ANOVA and post-hoc tests (α = 0.05). μTBS values were similar in cont-3 groups, and ABU/cont-4 and corresponding control groups, but were significantly lower in the other groups than in their control groups (P groups showed the lowest μTBS values (P blood contaminants and reapplying the adhesive may regain the dentin adhesion when contamination occurs before light curing. Alternatively, rinsing and drying contaminants followed by adhesive re-application may be effective depending on adhesive type.

  12. Bonding Properties of Basalt Fiber and Strength Reduction According to Fiber Orientation

    OpenAIRE

    Choi, Jeong-Il; Lee, Bang

    2015-01-01

    The basalt fiber is a promising reinforcing fiber because it has a relatively higher tensile strength and a density similar to that of a concrete matrix as well as no corrosion possibility. This study investigated experimentally the bonding properties of basalt fiber with cementitious material as well as the effect of fiber orientation on the tensile strength of basalt fiber for evaluating basalt fiber?s suitability as a reinforcing fiber. Single fiber pullout tests were performed and then th...

  13. Casein phosphopeptide-amorphous calcium phosphate and shear bond strength of adhesives to primary teeth enamel.

    Science.gov (United States)

    Farokh Gisovar, Elham; Hedayati, Nassim; Shadman, Niloofar; Shafiee, Leila

    2015-02-01

    CPP-ACP (Phosphopeptide-Amorphous Calcium Phosphate) has an important role in caries prevention in pediatric patients. This study was done, because of the great use of CPP-ACP and the need for restoration for teeth treated with CPP-ACP as well as the importance of shear bond strength of adhesives in the success of restorations. This study aimed to evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on shear bond strength of dental adhesives to enamel of primary teeth molars. This in vitro study was conducted on 180 extracted primary molars. They were randomly divided into 6 groups and each group was divided into 2 subgroups (treated with CPP-ACP and untreated). In subgroups with CPP-ACP, enamel was treated with CPP-ACP paste 1 h/d for 5 days. Types of adhesives that were evaluated in this study were Tetric N-Bond, AdheSE, AdheSE One F, single Bond 2, SE Bond, and Adper Prompt L-Pop. Shear bond strength was tested with a universal testing machine and mode of failure was evaluated under stereomicroscope. Data were analyzed by T test, 2-way analysis of variance (ANOVA), Tukey and Fisher exact test using SPSS18. P adhesive systems to enamel of primary teeth treated and untreated with CPP-ACP showed no significant difference (P > 0.05). Mode of failure in all groups regardless of CPP-ACP administration was mainly adhesive type. Our results indicated that CPP-ACP did not affect shear bond strength of studied adhesives to primary teeth enamel. To have a successful and durable composite restoration, having a high strength bonding is essential. Considering the wide use of CPP-ACP in preventing tooth decay and the role of adhesive shear bond strength (SBS) in success of composite restoration, we conducted the present study to evaluate the effect of CPP-ACP on the SBS of adhesives to primary teeth enamel.

  14. Effect of hydrostatic pressure on regional bond strengths of compomers to dentine.

    Science.gov (United States)

    Zheng, L; Pereira, P N; Somphone, P; Nikaido, T; Tagami, J

    2000-09-01

    The aim of this study was to evaluate the effect of hydrostatic pressure on the regional bond strengths of compomers to dentine. Thirty freshly extracted molars were ground flat to expose the dentine and randomly divided into two groups for bonding: no hydrostatic pressure and hydrostatic pressure of 15cm H(2)O. Xeno CF, Dyract AP and F 2000 were applied to dentine surfaces pretreated by the respective bonding systems following the manufactures' instructions, and then restored with Clearfil AP-X. After 24h storage in water, the teeth were sectioned into 0.7-mm thick slabs and visually divided into three regional subgroups: the region communicating with the pulp through dentinal tubules (pulp horn); the region between the pulp horns (center); and the region between the pulp horn and DEJ (periphery). The specimens were trimmed to a cross-sectional area of 1mm(2) and subjected to the micro-tensile bond test. The data were analyzed by one- and three-way ANOVA, and Fisher's PLSD (p0.05). However, hydrostatic pressure significantly decreased the bond strength of F 2000 to all regions (phydrostatic pressure (p>0.05). For Dyract AP and F 2000, the fracture modes were affected by hydrostatic pressure, while, for Xeno CF, there were no significant differences between the fracture modes with non- or positive hydrostatic pressure. Simulated pulpal pressure of 15cm H(2)O had a greater influence on the bond strengths of compomers to dentine than did dentine regions. Therefore, when measuring the bond strengths of compomers to dentine under the simulated in vivo conditions, the wetness of the dentine surface, as well as the intrinsic properties of each material should be seriously considered.

  15. Bond strengths of brackets bonded to enamel surfaces conditioned with femtosecond and Er:YAG laser systems.

    Science.gov (United States)

    Aglarci, Cahide; Demir, Necla; Aksakalli, Sertac; Dilber, Erhan; Sozer, Ozlem Akinci; Kilic, Hamdi Sukur

    2016-08-01

    The aim of this study was to compare femtosecond and Er:YAG laser systems with regard to enamel demineralization and bracket bond strength. Human-extracted premolars were randomized to three groups (n = 17) depending on the conditioning treatment used for the buccal surfaces: 37 % orthophosphoric acid, Er:YAG laser etching (MSP mode 120 mJ, 10 Hz, 1.2 W), and femtosecond laser etching (0.4 W, 800 nm, 90 fs/pulse, 1 kHz). Metal brackets were bonded with Transbond XT to the conditioned surfaces and light cured for 20 s. The samples were thermocycled (5000 cycles, 5-55 °C) and subjected to shear bond strength (SBS) testing using a universal testing machine. Failure types were analyzed under an optical stereomicroscope and SEM. The adhesive remnant index (ARI) was evaluated to assess residual adhesive on the enamel surface. The results revealed no significant differences in SBS between the Er:YAG laser (7.2 ± 3.3 MPa) and acid etching groups (7.3 ± 2.7 MPa; p enamel interface.

  16. Fracture and shear bond strength analyses of different dental veneering ceramics to zirconia

    International Nuclear Information System (INIS)

    Diniz, Alexandre C.; Nascimento, Rubens M.; Souza, Julio C.M.; Henriques, Bruno B.; Carreiro, Adriana F.P.

    2014-01-01

    The purpose of this work was to evaluate the interaction of different layering porcelains with zirconia via shear bond strength test and microscopy. Four different groups of dental veneering porcelains (VM9, Zirkonzanh, Ceramco, IPS) were fused onto forty zirconia-based cylindrical substrates (8 mm in diameter and 12 mm in height) (n = 10), according to the manufacturer's recommendations. Additionally, layered dental porcelain (D-sign, Ivoclar) was fired on ten Ni–Cr cylindrical substrates Shear bond strength tests of the veneering porcelain to zirconia or Ni–Cr were carried out at a crosshead speed of 0.5 mm/min. After the shear bond tests, the interfaces were analyzed by scanning electron microscopy (SEM). The fracture type exhibited by the different systems was also assessed. The results were statistically analyzed by ANOVA at a significant level of p < .05. The shear bond strength values of the porcelain-to-NiCr interfaces (25.3 ± 7.1 MPa) were significantly higher than those recorded for the following porcelain-to-zirconia systems: Zirkonzanh (18.8 ± 1 MPa), Ceramco (18.2 ± 4.7 MPa), and IPS (16 ± 4.5 MPa). However, no significant differences were found in the shear bond strength values between the porcelain-to-NiCr and porcelain (VM9)-to-zirconia (23.2 ± 5.1 MPa) groups (p > .05). All-ceramic interfaces revealed mixed failure type, cohesive in the porcelain and adhesive at the interface. This study demonstrated that all-ceramic systems do not attain yet the same bond strength standards equivalent to metal–ceramic systems. Therefore, despite the esthetic appeal of all-ceramic restorations, the adhesion between the porcelain and zirconia framework is still an issue considering the long term success of the restoration. - Highlights: • This study assessed the shear bond strength of different porcelains to zirconia. • The porcelain Vita VM9 showed a high shear bond strength to zirconia. • The fracture surface of all-ceramic systems revealed

  17. Fracture and shear bond strength analyses of different dental veneering ceramics to zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Diniz, Alexandre C. [School of Dentistry (DOD), Division of Prosthodontics, Universidade Federal do Rio Grande do Norte -UFRN, 59056-000, Natal (Brazil); Nascimento, Rubens M. [Materials Engineering Department, Universidade Federal do Rio Grande do Norte - UFRN, Natal (Brazil); Souza, Julio C.M. [Centre for Mechanics and Materials Technologies - CT2M, Department of Mechanical Engineering (DEM), Universidade do Minho, Campus Azurém, 4800-058, Guimarães (Portugal); Henriques, Bruno B. [Materials Engineering Department, Universidade Federal do Rio Grande do Norte - UFRN, Natal (Brazil); Centre for Mechanics and Materials Technologies - CT2M, Department of Mechanical Engineering (DEM), Universidade do Minho, Campus Azurém, 4800-058, Guimarães (Portugal); Carreiro, Adriana F.P., E-mail: adrianadafonte@hotmail.com [School of Dentistry (DOD), Division of Prosthodontics, Universidade Federal do Rio Grande do Norte -UFRN, 59056-000, Natal (Brazil)

    2014-05-01

    The purpose of this work was to evaluate the interaction of different layering porcelains with zirconia via shear bond strength test and microscopy. Four different groups of dental veneering porcelains (VM9, Zirkonzanh, Ceramco, IPS) were fused onto forty zirconia-based cylindrical substrates (8 mm in diameter and 12 mm in height) (n = 10), according to the manufacturer's recommendations. Additionally, layered dental porcelain (D-sign, Ivoclar) was fired on ten Ni–Cr cylindrical substrates Shear bond strength tests of the veneering porcelain to zirconia or Ni–Cr were carried out at a crosshead speed of 0.5 mm/min. After the shear bond tests, the interfaces were analyzed by scanning electron microscopy (SEM). The fracture type exhibited by the different systems was also assessed. The results were statistically analyzed by ANOVA at a significant level of p < .05. The shear bond strength values of the porcelain-to-NiCr interfaces (25.3 ± 7.1 MPa) were significantly higher than those recorded for the following porcelain-to-zirconia systems: Zirkonzanh (18.8 ± 1 MPa), Ceramco (18.2 ± 4.7 MPa), and IPS (16 ± 4.5 MPa). However, no significant differences were found in the shear bond strength values between the porcelain-to-NiCr and porcelain (VM9)-to-zirconia (23.2 ± 5.1 MPa) groups (p > .05). All-ceramic interfaces revealed mixed failure type, cohesive in the porcelain and adhesive at the interface. This study demonstrated that all-ceramic systems do not attain yet the same bond strength standards equivalent to metal–ceramic systems. Therefore, despite the esthetic appeal of all-ceramic restorations, the adhesion between the porcelain and zirconia framework is still an issue considering the long term success of the restoration. - Highlights: • This study assessed the shear bond strength of different porcelains to zirconia. • The porcelain Vita VM9 showed a high shear bond strength to zirconia. • The fracture surface of all-ceramic systems revealed

  18. Microtensile dentin bond strength of fifth with five seventh-generation dentin bonding agents after thermocycling: An in vitro study

    Directory of Open Access Journals (Sweden)

    Bruhvi Poptani

    2012-01-01

    Full Text Available Objectives: The objective of this in vitro study was to compare the microtensile dentin bond strength (μTBS of five seventh-generation dentin bonding agents (DBA with fifth-generation DBA before and after thermocycling. Materials and Methods: Ten extracted teeth were assigned to fifth generation control group (optibond solo and each of the five experimental groups namely, Group I (G-Bond ,Group II (S 3 Clearfil, Group III (One Coat 7.0, Group IV (Xeno V, and Group V (Optibond all in one. The crown portions of the teeth were horizontally sectioned below the central groove to expose the dentin. The adhesive resins from all groups were bonded to the teeth with their respective composites. Specimens of sizes 1 × 1 × 6 mm 3 were obtained. Fifty specimens that bonded to dentin from each group were selected. Twenty-five of the specimens were tested for debonding without thermocycling and the remaining were subjected to thermocycling followed by μTBS testing. The data were analyzed with one-way ANOVA and Dunnett′s-test for comparison with the reference group(Vth Generation. Results: There was no significant difference (P > 0.05 between the fifth- and seventh-generation adhesives before and after thermocycling. The results of our study showed significantly higher value (P < 0.05 of μTBS of seventh-generation Group II (Clearfil S 3 compared to the fifth-generation before and after thermocycling. Conclusion: The study demonstrated that the Clearfil S 3 bond had the highest μTBS values. In addition, of the five tested seventh-generation adhesive resins were comparable to the fifth-generation DBA.

  19. Influence of dentin contamination by temporary cements on the bond strength of adhesive systems

    Directory of Open Access Journals (Sweden)

    Josimeri Hebling

    2009-01-01

    Full Text Available Objective: The aim of this study was to assess the bond strength of adhesive systems to dentin contaminated by temporary cements with or without eugenol. Method: Flat dentin surfaces were obtained from twenty-four human third molars. With exception of the control group (n=8, the surfaces were covered with Interim Restorative Material (Caulk Dentsplay, Milford, DE, USA or Cavit (3M ESPE, St. Paul, MN, USA and kept in an oven at 37oC for seven days. After removing the cements, the adhesive systems Adper Single Bond (3M ESPE, St. Paul, MN, USA or Clearfil SE Bond (Kuraray Co. Ltd., Osaka, Japan were applied in accordance with the manufacturers’ recommendations, and then the crowns were constructed in of resin composite. The teeth were sectioned into specimens with a cross-sectional bond area of 0.81mm2, which were sub mitted to microtensile testing in a mechanical test machine at an actuator speed of 0.5mm/min. The data were analyzed by t- and ANOVA tests, complemented by Tukey tests (α=0.05. Results: For Adper Single Bond (3M ESPE, St. Paul, MN, USA, bond strength did not differ statistically (p>0.05 for all the experimental conditions. For Clearfil SE Bond (Kuraray Co. Ltd., Osaka, Japan, only the Interim Restorative Material (Caulk Dentsplay, Milford, DE, USA Group showed significantly lower bond strength (30.1±13.8 MPa in comparison with the other groups; control (38.9±13.5 MPa and Cavit (3M ESPE, St. Paul, MN, USA (42.1±11.0 MPa, which showed no significant difference between them.Conclusion: It was concluded that the previous covering of dentin with temporary cement containing eugenol had a deleterious effect on the adhesive performance of the self-etching system only.

  20. Push-off tests and strength evaluation of joints combining shrink fitting with bonding

    Science.gov (United States)

    Yoneno, Masahiro; Sawa, Toshiyuki; Shimotakahara, Ken; Motegi, Yoichi

    1997-03-01

    Shrink fitted joints have been used in mechanical structures. Recently, joints combining shrink fitting with anaerobic adhesives bonded between the shrink fitted surfaces have been appeared in order to increase the joint strength. In this paper, push-off test was carried out on strength of joints combining shrink fitting with bonding by material testing machine. In addition, the push-off strength of shrink fitting joints without an anaerobic adhesive was also measured. In the experiments, the effects of the shrinking allowance and the outer diameter of the rings on the joint strength are examined. The interface stress distribution in bonded shrink fitted joints subjected to a push-off load is analyzed using axisymmetrical theory of elasticity as a four-body contact problem. Using the interface stress distribution, a method for estimating joint strength is proposed. The experimental results are in a fairly good agreement with the numerical results. It is found that the strength of combination joints is greater than that of shrink fitted joints.

  1. In vitro comparison of the tensile bond strength of denture adhesives on denture bases.

    Science.gov (United States)

    Kore, Doris R; Kattadiyil, Mathew T; Hall, Dan B; Bahjri, Khaled

    2013-12-01

    With several denture adhesives available, it is important for dentists to make appropriate patient recommendations. The purpose of this study was to evaluate the tensile bond strength of denture adhesives on denture base materials at time intervals of up to 24 hours. Fixodent, Super Poligrip, Effergrip, and SeaBond denture adhesives were tested with 3 denture base materials: 2 heat-polymerized (Lucitone 199 and SR Ivocap) and 1 visible-light-polymerized (shade-stable Eclipse). Artificial saliva with mucin was used as a control. Tensile bond strength was tested in accordance with American Dental Association specifications at 5 minutes, 3 hours, 6 hours, 12 hours, and 24 hours after applying the adhesive. Maximum forces before failure were recorded in megapascals (MPa), and the data were subjected to a 2-way analysis of variance (α=.05). All 4 adhesives had greater tensile bond strength than the control. Fixodent, Super Poligrip, and SeaBond had higher tensile bond strength values than Effergrip. All adhesives had the greatest tensile bond strength at 5 minutes and the least at 24 hours. The 3 denture bases produced significantly different results with each adhesive (Padhesives had the greatest tensile bond strength, followed by Ivocap and Eclipse. All 4 adhesives had greater tensile bond strength than the control, and all 4 adhesives were strongest at the 5-minute interval. On all 3 types of denture bases, Effergrip produced significantly lower tensile bond strength, and Fixodent, Super Poligrip, and SeaBond produced significantly higher tensile bond strength. At 24 hours, the adhesive-base combinations with the highest tensile bond strength were Fixodent on Lucitone 199, Fixodent on Eclipse, Fixodent on Ivocap, and Super Poligrip on Ivocap. Copyright © 2013 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  2. Comparison of the Effect of two Denture Cleansers on Tensile bond Strength of a Denture Liner.

    Science.gov (United States)

    Farzin, M; Bahrani, F; Adelpour, E

    2013-09-01

    One of the most clinical challenging issues in prosthodontics is debonding of soft liners from the denture base. The aim of this study was to evaluate and compare tensile bond strength between soft liner and heat-cured acrylic resin when immersed in two different types of denture cleanser and distilled water, at different period of times. In this experimental in vivo study, 238 heat-cured acrylic blocks were made. A soft liner was embedded between the acrylic blocks. Samples were divided into four groups: 17 samples were in the control group and were not soaked in any solution .The remaining samples were divided into 3 groups (Distilled water, Calgon and Fittydent). Each group was then subdivided into two subcategories, regarding the immersion time variable; 15 and 45 minutes. All samples were placed in tension force and tensile bond strength was recorded with the testing machine. One- way ANOVA and Tucky HSD post-hoc test were adopted to analyze the yielded data (α> 0.05). Specimens which were immersed in two denture cleansers (Fittydent and Calgon) and in distilled water showed significant difference (p= 0.001) in bonding strength when compared to the control group. The subjects immersed in denture cleanser solutions and distilled water did not reveal any significant difference (p= 0.90). For all groups; most of the bonding failures (72%) were cohesive type. The effect of the denture cleansers and distilled water on the bond strength was not statistically different; however, the difference was significant between the immersed groups with the non-immersed group. Moreover, type of the denture cleanser did not show any effect on the tensile strength. The tensile strength increases with time of immersion.

  3. Long-lived, high-strength states of ICAM-1 bonds to beta2 integrin, II

    DEFF Research Database (Denmark)

    Kinoshita, Koji; Leung, Andrew; Simon, Scott

    2010-01-01

    Using single-molecule force spectroscopy to probe ICAM-1 interactions with recombinant alphaLbeta2 immobilized on microspheres and beta2 integrin on neutrophils, we quantified an impressive hierarchy of long-lived, high-strength states of the integrin bond, which start from basal levels with acti......Using single-molecule force spectroscopy to probe ICAM-1 interactions with recombinant alphaLbeta2 immobilized on microspheres and beta2 integrin on neutrophils, we quantified an impressive hierarchy of long-lived, high-strength states of the integrin bond, which start from basal levels......-out and outside-in signaling in neutrophils on the lifetimes and mechanical strengths of ICAM-1 bonds to beta2 integrin on the cell surface. Even though ICAM-1 bonds to recombinant alphaLbeta2 on microspheres in Mg2+ or Mn2+ can live for long periods of time under slow pulling, here we show that stimulation...... of neutrophils in Mg2+ plus the chemokine IL-8 (i.e., inside-out signaling) induces several-hundred-fold longer lifetimes for ICAM-1 attachments to LFA-1, creating strong bonds at very slow pulling speeds where none are perceived in Mg2+ or Mn2+ alone. Similar changes are observed with outside-in signaling, i...

  4. Evaluation of the shear bond strength of the Orthobond composite under different conditions

    Directory of Open Access Journals (Sweden)

    Antônio Carlos de Oliveira Ruellas

    2008-01-01

    Full Text Available Objective: Evaluate the shear bond strength of metal brackets bonded with Orthobond composite (Dental Morelli Ltda, Sorocaba, Brazil under different enamel surface conditions. Methods: Ninety bovine mandibular permanent incisors were divided into six groups (n = 15. In Group 1 (control and Group 2 the bonding procedures were performed by using Transbond XT (3M Unitek, Monrovia, USA and Orthobond (Dental Morelli Ltda, Sorocaba, Brazil composites,respectively, according to the manufacturer’s recommendations. In the other groups brackets were bonded with Orthobond composite (Dental Morelli Ltda, Sorocaba, Brazil as follows: Group 3 – dental surface conditioned with Transbond Plus Self-Etching Primer (3M Unitek, Monrovia, USA; Group 4 – bonding procedure without application of Orthoprimer (Dental Morelli Ltda, Sorocaba, Brazil; Group 5 - Eagle Bond applied on saliva/blood-contaminated dental surface; and Group 6 – use of homogenized Orthobond (Dental Morelli Ltda, Sorocaba, Brazil. After bonding the brackets, all the samples were submitted to shear bond strength tests by means of an Emic Universal Testing Machine at a crosshead speed of 0.5 mm/min. The results obtained in mega Pascal (MPa were submitted to the analysis of variance (ANOVA and then to the Tukey test. Results: The results in mega Pascal showed statistically significant differences between Groups 1 and 2 (p= 0.041, 1 and 5 (p=0.000 and between 4 and 5 (p=0.016. The ARI (Adhesive Remnant Index scores showed evidence of a higher number of fractures at the bracket/composite interface. Conclusion: In all tested situations the Orthobond (Dental Morelli Ltda, Sorocaba, Brazil was shown to be apt for bracket bonding.

  5. Crystal growth vs. conventional acid etching: A comparative evaluation of etch patterns, penetration depths, and bond strengths

    Directory of Open Access Journals (Sweden)

    Devanna Raghu

    2008-01-01

    Full Text Available The present study was undertaken to investigate the effect on enamel surface, penetration depth, and bond strength produced by 37% phosphoric acid and 20% sulfated polyacrylic acid as etching agents for direct bonding. Eighty teeth were used to study the efficacy of the etching agents on the enamel surface, penetration depth, and tensile bond strength. It was determined from the present study that a 30 sec application of 20% sulfated polyacrylic acid produced comparable etching topography with that of 37% phosphoric acid applied for 30 sec. The 37% phosphoric acid dissolves enamel to a greater extent than does the 20% sulfated polyacrylic acid. Instron Universal testing machine was used to evaluate the bond strengths of the two etching agents. Twenty percent sulfated polyacrylic acid provided adequate tensile bond strength. It was ascertained that crystal growth can be an alternative to conventional phosphoric acid etching as it dissolves lesser enamel and provides adequate tensile bond strength.

  6. Pullout bond strength of fiber posts luted to different depths and submitted to artificial aging.

    Science.gov (United States)

    Macedo, V C; Souza, N A Y; Faria e Silva, A L; Cotes, C; da Silva, C; Martinelli, M; Kimpara, E T

    2013-01-01

    The extension of fiber post cementation often does not seem to influence the fracture resistance of restorations. This study evaluated the effects of cementation depths on the retention of fiber posts submitted to artificial aging. One hundred and sixty bovine incisors were selected to assess post retention. Following endodontic treatment, the canals were flared with diamonds burs. Postholes were prepared in lengths of 5 or 10 mm, after which fiber posts were relined with composite resin and luted with RelyX ARC or RelyX Unicem. The samples were then submitted to thermal and/or mechanical cycling before testing their pullout bond strengths. Absence of cycling was used as a control. The results of each cement were submitted to two-way and post hoc Tukey tests (α=0.05). Independent of the aging protocol, a depth of 10 mm showed higher pullout bond strength than did 5 mm, except for RelyX Unicem without cycling. For RelyX ARC, thermomechanical cycling resulted in lower values than in the absence of cycling. Mechanical cycling alone promoted the highest bond strength when the posts were luted with RelyX Unicem. The effect of artificial aging on the pullout bond strength is dependent on the type of material and the depth.

  7. Shear bond strength of a self‑etched resin cement to an indirect ...

    African Journals Online (AJOL)

    2014-11-15

    Nov 15, 2014 ... was used to analyze the bond strength values of different groups. .... was 10 Hz, 3W, 300 mJ, at a distance of 10 mm from the .... gallium-garnet (Er,Cr:YSGG) group, (e) 2 W Er,Cr:YSGG group, (f) 3 W Er,Cr:YSGG group d c b f.

  8. Effect of a re‑wetting agent on bond strength of an adhesive to ...

    African Journals Online (AJOL)

    Objective: This study investigated the effect of a re‑wetting agent on the microtensile bond strengths (μTBS) of primary and permanent dentin after acid or laser etching. Materials and Methods: Twelve permanent and 12 primary molar teeth were ground to expose an occlusal dentin surface. Each group teeth were randomly ...

  9. Effect of chlorhexidine on the shear bond strength of self-etch ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the effect of chlorhexidine on shear bond strength of self-etch adhesives to dentin. The crowns of 60 sound human premolars were horizontally sectioned to expose the coronal dentin. Dentin surfaces were polished with 320 grit silicon carbide papers, and were randomly divided into 4 ...

  10. Determination of the bonding strength in solid oxide fuel cells' interfaces by Schwickerath crack initiation test

    DEFF Research Database (Denmark)

    Boccaccini, D. N.; Sevecek, O.; Frandsen, Henrik Lund

    2017-01-01

    An adaptation of the Schwickerath crack initiation test (ISO 9693) was used to determine the bonding strength between an anode support and three different cathodes with a solid oxide fuel cell interconnect. Interfacial elemental characterization of the interfaces was carried out by SEM/EDS analys...

  11. Effect of surface treatment of titanium posts on the tensile bond strength

    NARCIS (Netherlands)

    Schmage, P; Sohn, J; Ozcan, M; Nergiz, [No Value

    Objectives. Retention of composite resins to metal can be improved when metal surfaces are conditioned. The purpose of this investigation was to investigate the effect of two conditioning treatments on the tensile bond strength of four resin-based luting cements and zinc phosphate cement to titanium

  12. Shear bond strengths of three glass ionomer cements to enamel and dentine

    NARCIS (Netherlands)

    Carvalho, T.S.; van Amerongen, W.E.; de Gee, A.; Bönecker, M.; Sampaio, F.C.

    2011-01-01

    Objectives: The shear bond strength of three glass ionomer cements (GIC) to enamel and dentine was evaluated. Study Design: Sound permanent human molars (n=12) were grinded perpendicular to their axial axes, exposing smooth, flat enamel and dentine surfaces. The teeth were embedded in resin and

  13. Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments

    DEFF Research Database (Denmark)

    Furuse, Adilson Yoshio; da Cunha, Leonardo Fernandes; Benetti, Ana Raquel

    2007-01-01

    of silane and adhesive system. Resin cylinders were placed over the treated surfaces. The specimens were stored in water or ethanol. Shear bond strength tests were performed and the mode of failure was evaluated. Data were submitted to two-way ANOVA and Dunnett T3 test. Contamination of resin...

  14. Microtensile bond strength of three simplified adhesive systems to caries-affected dentin

    NARCIS (Netherlands)

    Scholtanus, J.D.; Purwanta, K.; Dogan, N.; Kleverlaan, C.J.; Feilzer, A.J.

    2010-01-01

    Purpose: The purpose of the study was to determine the microtensile bond strength of three different simplified adhesive systems to caries-affected dentin. Materials and Methods: Fifteen extracted human molars with primary carious lesions were ground flat until dentin was exposed. Soft

  15. Microtensile Bond Strength of Three Simplified Adhesive Systems to Caries-affected Dentin

    NARCIS (Netherlands)

    Scholtanus, Johannes; Purwanta, Kenny; Dogan, Nilgun; Kleverlaan, Cees J.; Feilzer, Albert J.

    Purpose: The purpose of the study was to determine the microtensile bond strength of three different simplified adhesive systems to caries-affected dentin. Materials and Methods: Fifteen extracted human molars with primary carious lesions were ground flat until dentin was exposed. Soft

  16. Ceramic inlays : effect of mechanical cycling and ceramic type on restoration-dentin bond strength

    NARCIS (Netherlands)

    Trindade, F.Z.; Kleverlaan, C.J.; da Silva, L.H.; Feilzer, A.J.; Cesar, P.F.; Bottino, M.A.; Valandro, L.F.

    2016-01-01

    This study aimed to evaluate the bond strength between dentin and five different ceramic inlays in permanent maxillary premolars, with and without mechanical cycling. One hundred permanent maxillary premolars were prepared and divided into 10 groups (n=10) according to the ceramic system (IPS e.Max

  17. Investigation of the bond strength between the photo-sensitive polymer SU-8 and gold

    DEFF Research Database (Denmark)

    Nordström, Maria; Johansson, Alicia; Sánchez Noguerón, E.

    2005-01-01

    adhesion promotors between the SU-8 and Au; (ii) the influence of the processing sequence, keeping either Au or SU-8 as the bottom layer; (iii) the importance of the UV exposure dosage of the SU-8. For comparison, also the bond strength between SU-8 and other materials was measured. For SU-8 and Au without...

  18. Can Whitening Strips interfere with the Bond Strength of Composite Resins?

    Science.gov (United States)

    Firoozmand, Leily Macedo; Reis, Washington Luís Machado dos; Vieira, Mercêdes Aroucha; Nunes, Adriana Gomes; Tavarez, Rudys Rodolfo de Jesus; Tonetto, Mateus Rodrigues; Bramante, Fausto Silva; Bhandi, Shilpa H; Roma, Regina Vieira de Oliveira; Bandeca, Matheus Coelho

    2015-04-01

    The aim of this study was to investigate in vitro the bond strength of composite resins on enamel previously treated with whitening strips. A total of 48 bovine incisors were allocated to four experimental groups (n = 12 each): G1 (WSC)- treated with 9.5% hydrogen peroxide whitening strips (3D White Whitestrips® Advanced Vivid/CREST); G2 (WSO)-treated with 10% hydrogen peroxide whitening strips (3D WhiteTM/Oral B); G3 (WG)-treated with 7.5% hydrogen peroxide gel with fluorine, calcium and potassium nitrate (White Class®/FGM); and G4 (C)-control not subjected to bleaching treatment. The specimens were subjected to bleaching over 2 weeks following the manufacturers' instructions. Following the elaboration of the composite resin test specimens, the samples were stored in artificial saliva and subsequently subjected to the micro-shear test using the universal testing machine (EMIC®). The bond strength values were analyzed by one-way ANOVA and Tukey's statistical test (5%). Significant differences were observed among the investigated groups (p enamel-resin interface. The bond strength decreased following 14 days of treatment with bleaching strips, whereas the whitening gel with 7.5% hydrogen peroxide, calcium and fluorine increased the bond strength.

  19. Push-Out Bond Strength of Restorations with Bulk-Fill, Flow, and Conventional Resin Composites

    Directory of Open Access Journals (Sweden)

    Rodrigo Vieira Caixeta

    2015-01-01

    Full Text Available The aim of this study was to evaluate the bond strengths of composite restorations made with different filler amounts and resin composites that were photoactivated using a light-emitting diode (LED. Thirty bovine incisors were selected, and a conical cavity was prepared in the facial surface of each tooth. All preparations were etched with Scotchbond Etching Gel, the Adper Scotchbond Multipurpose Plus adhesive system was applied followed by photoactivation, and the cavities were filled with a single increment of Filtek Z350 XT, Filtek Z350 XT Flow, or bulk-fill X-tra fil resin composite (n = 10 followed by photoactivation. A push-out test to determine bond strength was conducted using a universal testing machine. Data (MPa were submitted to Student’s t-test at a 5% significance level. After the test, the fractured specimens were examined using an optical microscope under magnification (10x. Although all three composites demonstrated a high prevalence of adhesive failures, the bond strength values of the different resin composites photoactivated by LED showed that the X-tra fil resin composite had a lower bond strength than the Filtek Z350 XT and Filtek Z350 XT Flow resin composites.

  20. Evaluation of bond strength of a conventional adhesive system in irradiated teeth

    Directory of Open Access Journals (Sweden)

    Emanuel Jordan de CARVALHO

    Full Text Available Abstract Introduction One of the most common treatments of head and neck cancer patients is radiotherapy, a treatment method which uses ionizing radiation beam and destroys tumor cells, minimizing damage to neighbor cells. Purpose To evaluate the bond strength of a conventional adhesive system in irradiated teeth. Method 24 third human molars, 12 of which were randomly exposed to radiation and prepared from the removal of occlusal enamel, then exposed to a flat dentine surface. The adhesive system Stae was applied according to the manufacturer’s instructions. Next, two 2 mm increments of resin were implemented. The samples were hemi sectioned specimens, originating shapped toothpick. To evaluate the bond strength, a micro tensile test was done with 500N load and speed of 0.5 mm/minute. Result There was no statistically significant difference between the bond strength of teeth which were or were not exposed to radiation and which used a conventional adhesive system. Conclusion Although the radiation doses applied may cause some alterations in microscopic range in dental tissues, it can be concluded that these alterations do not influence in the bond strength in dentin of irradiated teeth.

  1. Effect of Irradiation on the Shear Bond Strength of Self-adhesive ...

    African Journals Online (AJOL)

    2016-02-05

    Feb 5, 2016 ... changes in the crystalline structure of dental hard tissues. Keywords: Bond strength, irradiation, self-adhesive luting cement. Effect of Irradiation on the .... The metal ring was connected with the cross-head and loaded (speed 1 ...

  2. Comparison of two bond strength testing methodologies for bilayered all-ceramics

    NARCIS (Netherlands)

    Dundar, Mine; Ozcan, Mutlu; Gokce, Bulent; Comlekoglu, Erhan; Leite, Fabiola; Valandro, Luiz Felipe

    Objectives. This study compared the shear bond strength (SBS) and microtensile (MTBS) testing methodologies for core and veneering ceramics in four types of all-ceramic systems. Methods. Four different ceramic veneer/core combinations, three of which were feldspathic and the other a fluor-apatite to

  3. Influence of EDC on Dentin-Resin Shear Bond Strength and Demineralized Dentin Thermal Properties

    Directory of Open Access Journals (Sweden)

    Lin Tang

    2016-11-01

    Full Text Available This study aimed to evaluate the bonding strength and thermal properties of demineralized dentin with and without EDC treatment. Sound human molars were randomly divided into seven treatment groups (n = 20: control, 80% ethanol, and five EDC ethanol solutions (0.01–1.0 M. In each group, 16 samples were used for bond strength assessment and 4 samples were used for scanning electron microscopy (SEM analysis. A further 70 intact molars were used to obtain a fine demineralized dentin powder, treated with the same solutions and were evaluated the crosslink degree by ninhydrin test and denaturation temperature (Td by differential scanning calorimetry. EDC-treated specimens (<1.0 M had a higher bond strength, especially 0.3 and 0.5 M group, than the control counterpart. There was a significant drop in bond strength of 1.0 M EDC group. SEM revealed a homogeneous and regular interface under all treatments. EDC treatment significantly increased the demineralized dentin cross-link degree and Td compared with the control and ethanol treatments. The 0.3 and 0.5 M treatments showed the highest cross-link degree and Td. In terms of mechnical and theramal properties consideration, 0.3 and 0.5 M EDC solutions may be favorable for when applied with etch-and-rinse adhesives, but it is still needed further long-term study.

  4. Effect of provisional cements on shear bond strength of porcelain laminate veneers.

    Science.gov (United States)

    Altintas, Subutay Han; Tak, Onjen; Secilmis, Asli; Usumez, Aslihan

    2011-08-01

    The purpose of this study was to evaluate the effect of three provisional cements and two cleaning techniques on the final bond strength of porcelain laminate veneers. The occlusal third of the crowns of forty molar teeth were sectioned and embedded in autopolymerizing acrylic resin. Dentin surfaces were polished and specimens were randomly divided into four groups (n=10). Provisional restorations were fabricated and two provisional restorations were cemented onto each tooth. Restorations were fixed with one of three different provisional cements: eugenol-free provisional cement (Cavex), calcium hydroxide (Dycal), and light-cured provisional cement (Tempond Clear). Provisional restorations were removed with either a dental explorer and air-water spray, or a cleaning bur (Opticlean). In the control group, provisional restorations were not used on the surfaces of specimens. IPS Empress 2 ceramic discs were luted with a dual-cured resin cement (Panavia F). Shear bond strength was measured using a universal testing machine. Data were statistically analyzed by ANOVA, Tukey's HSD and Dunnett tests. Surfaces were examined by scanning electronic microscopy. Significant differences were found between the control group and both the light-cured provisional cement groups and the eugenol-free provisional cement-cleaning bur group (Pprovisional cement showed the lowest bond strength values. Selection of the provisional cement is an important factor in the ultimate bond strength of the final restoration. Calcium hydroxide provisional cement and cleaning with a dental explorer are advisable.

  5. Effect of various bleaching treatments on shear bond strength of different universal adhesives and application modes

    Science.gov (United States)

    2018-01-01

    Objectives The aim of this in vitro study was to evaluate the bond strength of 2 universal adhesives used in different application modes to bleached enamel. Materials and Methods Extracted 160 sound human incisors were used for the study. Teeth were divided into 4 treatment groups: No treatment, 35% hydrogen peroxide, 16% carbamid peroxide, 7.5% carbamid peroxide. After bleaching treatments, groups were divided into subgroups according to the adhesive systems used and application modes (n = 10): 1) Single Bond Universal, etch and rinse mode; 2) Single Bond Universal, self-etch mode; 3) Gluma Universal, etch and rinse mode; 4) Gluma Universal, self-etch mode. After adhesive procedures nanohybrid composite resin cylinders were bonded to the enamel surfaces. All specimens were subjected to shear bond strength (SBS) test after thermocycling. Data were analyzed using a 3-way analysis of variance (ANOVA) and Tukey post hoc test. Results No significant difference were found among bleaching groups (35% hydrogen peroxide, 16% carbamid peroxide, 7.5% carbamid peroxide, and no treatment groups) in the mean SBS values. There was also no difference in SBS values between Single Bond Universal and Gluma Universal at same application modes, whereas self-etch mode showed significantly lower SBS values than etch and rinse mode (p adhesives was enhanced with the etch and rinse mode application to bleached enamel and non-bleached enamel. PMID:29765900

  6. Efficacy of quercetin flavonoid in recovering the postbleaching bond strength of orthodontic brackets: A preliminary study.

    Science.gov (United States)

    Shamsedin, Mana; Arash, Valiollah; Jahromi, Masoud Babaei; Moghadamnia, Ali Akbar; Kamel, Manouchehr Rahmati; Ezoji, Fariba; Bijani, Ali; Kavoli, Samira; Ghasemi, Tania; Ramezani, Gholamhossein

    2017-01-01

    To evaluate comparatively the effect of quercetin on postbleaching shear bond strength (SBS) and adhesive remnant index (ARI). Intact maxillary premolars were divided randomly into 12 groups of 10 each: (1) bonding the bracket immediately after bleaching, (2) bonding 1 week after bleaching, (3-8) application of three experimental concentrations of quercetin (0.1%, 0.5%, and 1%) at two time durations (5 and 10 min), (9-10) application of the solvent of quercetin at two time periods (5 and 10 min), (11) application of 10% sodium ascorbate for 10 min, and (12) bonding the brackets on nonbleached teeth. Bleaching was performed using 15% carbamide peroxide gel for 5 days (6 h daily). After incubation and thermocycling, the SBS of brackets was measured. The ARI too was recorded at ×20. The data were analyzed statistically (α =0.05). Bleaching reduced the SBS below 10 Megapascal (MPa) level ( P 0.01). All eight postbleaching treatments had rather similar efficacies ( P = 0.1396). The concentration of quercetin (beta = 0.259, P = 0.042) but not its duration (beta = 0.213, P = 0.093) significantly improved its efficacy. Bleaching can weaken the bond strength of orthodontic brackets below acceptable levels. The application of quercetin or Vitamin C or delaying the bracket bonding improved the postbleaching SBS.

  7. Improving Tensile Bond Strength of Orthodontic Bracket by Applying Papain Gel as an Email Deproteinization Agent

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    Niswati Fathmah Rosyida

    2017-12-01

    Full Text Available An effort to improve the bonding between bracket and tooth surface is required. Objective: The aim of this studywas to evaluate the effect of papain gel on tensile bond strength (TBS and adhesive remnant index (ARI of the orthodontic brackets. Methods: A total of 42 healthy human premolars were randomly divided into six groups. 1 Resin-modifed glass ionomer cement (RMGIC without papain, 2 RMGIC with papain 8%, 3 RMGIC with papain 10%, 4 Composite resin (CR without papain, 5 CR with papain 8%, 6 CR with papain 10%. The TBS was determined using a universal testing machine. Bond failure was classifed according to the ARI. The TBS data were analyzed with Kruskal-Wallis test followed by Mean Whitney tests with 5% of signifcance level. Results: The mean of TBS(MPa values of RMGIC groups are without papain (5.03 ± 1.52, papain 8% (4.79 ± 2.61, papain 10 (7.75 ± 1, 48. CR groups without papain (5.45 ± 1.23, papain 8% (2.30 ± 0.73, and papain 10% (4.84 ± 1.72 Bond failure was mainly classifed as score 1. The TBS values were statistically influenced by the application of papain and adhesive. Conclusion: The application of papain 10% before RMGIC cementation improves the tensile bond strength and could decrease the bond failure of the orthodontic bracket.

  8. Effect of moisture and drying time on the bond strength of the one-step self-etching adhesive system

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    Yoon Lee

    2012-08-01

    Full Text Available Objectives To investigate the effect of dentin moisture degree and air-drying time on dentin-bond strength of two different one-step self-etching adhesive systems. Materials and Methods Twenty-four human third molars were used for microtensile bond strength testing of G-Bond and Clearfil S3 Bond. The dentin surface was either blot-dried or air-dried before applying these adhesive agents. After application of the adhesive agent, three different air drying times were evaluated: 1, 5, and 10 sec. Composite resin was build up to 4 mm thickness and light cured for 40 sec with 2 separate layers. Then the tooth was sectioned and trimmed to measure the microtensile bond strength using a universal testing machine. The measured bond strengths were analyzed with three-way ANOVA and regression analysis was done (p = 0.05. Results All three factors, materials, dentin wetness and air drying time, showed significant effect on the microtensile bond strength. Clearfil S3 Bond, dry dentin surface and 10 sec air drying time showed higher bond strength. Conclusions Within the limitation of this experiment, air drying time after the application of the one-step self-etching adhesive agent was the most significant factor affecting the bond strength, followed by the material difference and dentin moisture before applying the adhesive agent.

  9. Bond strength and morphology of enamel using self-etching adhesive systems with different acidities

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    Sandra Kiss Moura

    2009-08-01

    Full Text Available OBJECTIVES: To assess the bond strength and the morphology of enamel after application of self-etching adhesive systems with different acidities. The tested hypothesis was that the performance of the self-etching adhesive systems does not vary for the studied parameters. MATERIAL AND METHODS: Composite resin (Filtek Z250 buildups were bonded to untreated (prophylaxis and treated (bur-cut or SiC-paper enamel surfaces of third molars after application of four self-etching and two etch-and-rinse adhesive systems (n=6/condition: Clearfil SE Bond (CSE; OptiBond Solo Plus Self-Etch (OP; AdheSe (AD; Tyrian Self Priming Etching (TY, Adper Scotchbond Multi-Purpose Plus (SBMP and Adper Single Bond (SB. After storage in water (24 h/37°C, the bonded specimens were sectioned into sticks with 0.8 mm² cross-sectional area and the microtensile bond strength was tested at a crosshead speed of 0.5 mm/min. The mean bond strength values (MPa were subjected to two-way ANOVA and Tukey's test (α=0.05. The etching patterns of the adhesive systems were also observed with a scanning electron microscope. RESULTS: The main factor adhesive system was statistically significant (p<0.05. The mean bond strength values (MPa and standard deviations were: CSE (20.5±3.5, OP (11.3±2.3, AD (11.2±2.8, TY (11.1±3.0, SBMP (21.9±4.0 and SB (24.9±3.0. Different etching patterns were observed for the self-etching primers depending on the enamel treatment and the pH of the adhesive system. CONCLUSION: Although there is a tendency towards using adhesive systems with simplified application procedures, this may compromise the bonding performance of some systems to enamel, even when the prismless enamel is removed.

  10. Effect of LASER Irradiation on the Shear Bond Strength of Zirconia Ceramic Surface to Dentin

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    Sima Shahabi

    2012-09-01

    Full Text Available Background and Aims: Reliable bonding between tooth substrate and zirconia-based ceramic restorations is always of great importance. The laser might be useful for treatment of ceramic surfaces. The aim of the present study was to investigate the effect of laser irradiation on the shear bond strength of zirconia ceramic surface to dentin. Materials and Methods: In this experimental in vitro study, 40 Cercon zirconia ceramic blocks were fabricated. The surface treatment was performed using sandblasting with 50-micrometer Al2O3, CO2 laser, or Nd:YAG laser in each test groups. After that, the specimens were cemented to human dentin with resin cement. The shear bond strength of ceramics to dentin was determined and failure mode of each specimen was analyzed by stereo-microscope and SEM investigations. The data were statistically analyzed by one-way analysis of variance and Tukey multiple comparisons. The surface morphology of one specimen from each group was investigated under SEM. Results: The mean shear bond strength of zirconia ceramic to dentin was 7.79±3.03, 9.85±4.69, 14.92±4.48 MPa for CO2 irradiated, Nd:YAG irradiated, and sandblasted specimens, respectively. Significant differences were noted between CO2 (P=0.001 and Nd:YAG laser (P=0.017 irradiated specimens with sandblasted specimens. No significant differences were observed between two laser methods (P=0.47. The mode of bond failure was predominantly adhesive in test groups (CO2 irradiated specimens: 75%, Nd:YAG irradiated: 66.7%, and sandblasting: 41.7%. Conclusion: Under the limitations of the present study, surface treatment of zirconia ceramics using CO2 and Nd:YAG lasers was not able to produce adequate bond strength with dentin surfaces in comparison to sandblasting technique. Therefore, the use of lasers with the mentioned parameters may not be recommended for the surface treatment of Cercon ceramics.

  11. Four chemical methods of porcelain conditioning and their influence over bond strength and surface integrity

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    Stella, João Paulo Fragomeni; Oliveira, Andrea Becker; Nojima, Lincoln Issamu; Marquezan, Mariana

    2015-01-01

    OBJECTIVE: To assess four different chemical surface conditioning methods for ceramic material before bracket bonding, and their impact on shear bond strength and surface integrity at debonding. METHODS: Four experimental groups (n = 13) were set up according to the ceramic conditioning method: G1 = 37% phosphoric acid etching followed by silane application; G2 = 37% liquid phosphoric acid etching, no rinsing, followed by silane application; G3 = 10% hydrofluoric acid etching alone; and G4 = 10% hydrofluoric acid etching followed by silane application. After surface conditioning, metal brackets were bonded to porcelain by means of the Transbond XP system (3M Unitek). Samples were submitted to shear bond strength tests in a universal testing machine and the surfaces were later assessed with a microscope under 8 X magnification. ANOVA/Tukey tests were performed to establish the difference between groups (α= 5%). RESULTS: The highest shear bond strength values were found in groups G3 and G4 (22.01 ± 2.15 MPa and 22.83 ± 3.32 Mpa, respectively), followed by G1 (16.42 ± 3.61 MPa) and G2 (9.29 ± 1.95 MPa). As regards surface evaluation after bracket debonding, the use of liquid phosphoric acid followed by silane application (G2) produced the least damage to porcelain. When hydrofluoric acid and silane were applied, the risk of ceramic fracture increased. CONCLUSIONS: Acceptable levels of bond strength for clinical use were reached by all methods tested; however, liquid phosphoric acid etching followed by silane application (G2) resulted in the least damage to the ceramic surface. PMID:26352845

  12. Influence of surface treatment on shear bond strength of orthodontic brackets

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    Ione Helena Vieira Portella Brunharo

    2013-06-01

    Full Text Available INTRODUCTION: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. METHODS: Two hundred and eighty test samples were divided into 28 groups (n = 10, where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. RESULTS: Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27±2.78; burs 9.26±3.01; stone 7.95±3.67; aluminum oxide blasting 7.04±3.21; phosphoric acid 5.82±1.90; hydrofluoric acid 4.54±2.87, and without treatment 2.75±1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83, burs (0.98 and stone drilling (0.46. CONCLUSION: The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

  13. Influence of surface treatment on shear bond strength of orthodontic brackets.

    Science.gov (United States)

    Brunharo, Ione Helena Vieira Portella; Fernandes, Daniel Jogaib; de Miranda, Mauro Sayão; Artese, Flavia

    2013-01-01

    The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27 ± 2.78; burs 9.26 ± 3.01; stone 7.95 ± 3.67; aluminum oxide blasting 7.04 ± 3.21; phosphoric acid 5.82 ± 1.90; hydrofluoric acid 4.54 ± 2.87, and without treatment 2.75 ± 1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83), burs (0.98) and stone drilling (0.46). The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

  14. Bond strength of universal adhesives: A systematic review and meta-analysis.

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    Rosa, Wellington Luiz de Oliveira da; Piva, Evandro; Silva, Adriana Fernandes da

    2015-07-01

    A systematic review was conducted to determine whether the etch-and-rinse or self-etching mode is the best protocol for dentin and enamel adhesion by universal adhesives. This report followed the PRISMA Statement. A total of 10 articles were included in the meta-analysis. Two reviewers performed a literature search up to October 2014 in eight databases: PubMed, Web of Science, Scopus, BBO, SciELO, LILACS, IBECS and The Cochrane Library. In vitro studies evaluating the bond strength of universal adhesives to dentin and/or enamel by the etch-and-rinse and self-etch strategies were eligible to be selected. Statistical analyses were conducted using RevMan 5.1 (The Cochrane Collaboration, Copenhagen, Denmark). A global comparison was performed with random-effects models at a significance level of puniversal adhesives (p≥0.05). However, for the ultra-mild All-Bond Universal adhesive, the etch-and-rinse strategy was significantly different than the self-etch mode in terms of dentin micro-tensile bond strength, as well as in the global analysis of enamel micro-tensile and micro-shear bond strength (p≤0.05). The enamel bond strength of universal adhesives is improved with prior phosphoric acid etching. However, this effect was not evident for dentin with the use of mild universal adhesives with the etch-and-rinse strategy. Selective enamel etching prior to the application of a mild universal adhesive is an advisable strategy for optimizing bonding. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Effect of different methods of enamel conditioning on bond strength of orthodontic brackets

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    Davari AR

    2007-01-01

    Full Text Available Background and Aim: With the introduction of different bondable restorative materials in dentistry, various methods have been suggested to enhance the polymerization and shear bond strength of these materials. The aim of this study was to determine the effects of different methods of enamel conditioning on bond strength of orthodontic brackets and on the bracket/ adhesive failure mode. Materials and Methods: In this experimental in vitro study, brackets were bonded to thirty-six bovine incisor teeth with different protocols according to the manufacturer's instructions as follows: Group 1: conventional multistep adhesive (n=12; Group 2: self-etching primer system (n=12; Group 3: acid+self-etching primer system (n=12. Specimens were loaded in a universal testing machine (Instron, Canton and Mass and the mode of failure was recorded. Data were analyzed by ANOVA and Kruskall-Wallis tests with p<0.05 as the limit of significance. Results: The mean shear bond strength was 11.7 ± 4.2, 10.5 ± 4.4, and 10.9 ± 4.8 MPa for group 1, 2, and 3 respectively. There was no significant difference in bond strength among the three groups (P=0.800. No significant difference was observed among the three groups with respect to residual adhesive on the enamel surfaces (P=0.554. Conclusion: Based on the results of the present study, the use of self-etching primers may be an alternative to conventional phosphoric acid pre-treatment in orthodontic bonding.

  16. Effect of Sodium Ascorbate and Delayed Bonding on the Bond Strength of Silorane and Two-step Self-etch Adhesive Systems in Bleached Enamel

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    Mehdi Abed Kahnemooyi

    2014-12-01

    Full Text Available Background and aims. Studies have shown decreased bond strength of composite resin to human and bovine bleached enamel. This study evaluated the effect of sodium ascorbate and delayed bonding on the bond strength of two adhesive systems to bleached enamel. Materials and methods. The labial surfaces of 150 sound bovine incisor teeth were abraded with abrasive paper. The teeth were randomly divided into 8 groups: A: control; B: bleached with 35% hydrogen peroxide; C: bleached with 35% hydrogen peroxide + sodium ascorbate gel; and D: bleached with 35% hydrogen peroxide + delayed bonding. In groups A‒D, silorane adhesive system and Filtek silorane composite resin were used. In groups E‒H, the same preparation methods of groups A‒D were used. Two-step self-etch Clearfil SE Bond adhesive systems and AP-X composite resin were administered. Shear bond strength of each group was measured. Two samples were prepared for each surface preparation for ultrastructural evaluation. Two-way ANOVA and Tukey test were used for data analysis at P<0.05. Results. The interaction between the adhesive system type and surface preparation protocol was significant (P=0.014, with significant differences in shear bond strengths in terms of the adhesive systems (P<0.01. There were significant differences in shear bond strength in terms of surface preparation techniques irrespective of the adhesive system (P<0.01. Conclusion. The results showed that bleaching with 35% hydrogen peroxide decreased the shear bond strength values with both adhesive systems, and a one-week delay in bonding and 10% sodium ascorbate for 10 minutes restored the bond strength in both adhesive systems.

  17. Influence of different adhesive systems on the pull-out bond strength of glass fiber posts.

    Science.gov (United States)

    da Silva, Luciana Mendonça; Andrade, Andréa Mello de; Machuca, Melissa Fernanda Garcia; da Silva, Paulo Maurício Batista; da Silva, Ricardo Virgolino C; Veronezi, Maria Cecília

    2008-01-01

    This in vitro study evaluated the tensile bond strength of glass fiber posts (Reforpost - Angelus-Brazil) cemented to root dentin with a resin cement (RelyX ARC - 3M/ESPE) associated with two different adhesive systems (Adper Single Bond - 3M/ESPE and Adper Scotchbond Multi Purpose (MP) Plus - 3M/ESPE), using the pull-out test. Twenty single-rooted human teeth with standardized root canals were randomly assigned to 2 groups (n=10): G1- etching with 37% phosphoric acid gel (3M/ESPE) + Adper Single Bond + #1 post (Reforpost - Angelus) + four #1 accessory posts (Reforpin - Angelus) + resin cement; G2- etching with 37% phosphoric acid gel + Adper Scotchbond MP Plus + #1 post + four #1 accessory posts + resin cement. The specimens were stored in distilled water at 37 degrees C for 7 days and submitted to the pull-out test in a universal testing machine (EMIC) at a crosshead speed of 0.5 mm/min. The mean values of bond strength (kgf) and standard deviation were: G1- 29.163 +/- 7.123; G2- 37.752 +/-13.054. Statistical analysis (Student's t-test; a=0.05 showed no statistically significant difference (pAdhesive bonding failures between resin cement and root canal dentin surface were observed in both groups, with non-polymerized resin cement in the apical portion of the post space when Single Bond was used (G1). The type of adhesive system employed on the fiber post cementation did not influence the pull-out bond strength.

  18. Influence of different adhesive systems on the pull-out bond strength of glass fiber posts

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    Luciana Mendonça da Silva

    2008-06-01

    Full Text Available This in vitro study evaluated the tensile bond strength of glass fiber posts (Reforpost - Angelus-Brazil cemented to root dentin with a resin cement (RelyX ARC - 3M/ESPE associated with two different adhesive systems (Adper Single Bond - 3M/ESPE and Adper Scotchbond Multi Purpose (MP Plus - 3M/ESPE, using the pull-out test. Twenty single-rooted human teeth with standardized root canals were randomly assigned to 2 groups (n=10: G1- etching with 37% phosphoric acid gel (3M/ESPE + Adper Single Bond + #1 post (Reforpost - Angelus + four #1 accessory posts (Reforpin - Angelus + resin cement; G2- etching with 37% phosphoric acid gel + Adper Scotchbond MP Plus + #1 post + four #1 accessory posts + resin cement. The specimens were stored in distilled water at 37°C for 7 days and submitted to the pull-out test in a universal testing machine (EMIC at a crosshead speed of 0.5 mm/min. The mean values of bond strength (kgf and standard deviation were: G1- 29.163 ± 7.123; G2- 37.752 ±13.054. Statistical analysis (Student's t-test; a=0.05 showed no statistically significant difference (p<0.05 between the groups. Adhesive bonding failures between resin cement and root canal dentin surface were observed in both groups, with non-polymerized resin cement in the apical portion of the post space when Single Bond was used (G1. The type of adhesive system employed on the fiber post cementation did not influence the pull-out bond strength.

  19. Desensitizing bioactive agents improves bond strength of indirect resin-cemented restorations: preliminary results

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    Fernanda de Carvalho Panzeri Pires-de-Souza

    2007-04-01

    Full Text Available OBJECTIVE: The aim of this study was to assess the bond strength of indirect composite restorations cemented with a resin-based cement associated with etch-and-rinse and self-etching primer adhesive systems to dentin treated or not with a bioactive material. MATERIALS AND METHOD: Twenty bovine incisor crowns had the buccal enamel removed and the dentin ground flat. The teeth were assigned to 4 groups (n=5: Group I: acid etching + Prime & Bond NT (Dentsply; Group II: application of a bioactive glass (Biosilicato®+ acid etching + Prime & Bond NT; Group III: One-up Bond F (J Morita; Group IV: Biosilicato® + One-up Bond F. Indirect composite resin (Artglass, Kulzer cylinders (6x10mm were fabricated and cemented to the teeth with a dual-cure resin-based cement (Enforce, Dentsply. After cementation, the specimens were stored in artificial saliva at 37ºC for 30 days and thereafter tested in tensile strength in a universal testing machine (EMIC with 50 kgf load cell at a crosshead speed of 1 mm/min. Failure modes were assessed under scanning electron microscopy. Data were analyzed statistically by ANOVA and Tukey's test (95% level of confidence. RESULTS: Groups I, II and III had statistically similar results (p>0.05. Group IV had statistically significant higher bond strength means (p<0.05 than the other groups. The analysis of the debonded surfaces showed a predominance of adhesive failure mode for Group III and mixed failure mode for the other groups. CONCLUSION: The use of desensitizing agent did not affect negatively the bonding of the indirect composite restorations to dentin, independently of the tested adhesive systems.

  20. The effects of silver coating on friction coefficient and shear bond strength of steel orthodontic brackets.

    Science.gov (United States)

    Arash, Valiollah; Anoush, Keivan; Rabiee, Sayed Mahmood; Rahmatei, Manuchehr; Tavanafar, Saeid

    2015-01-01

    Aims of the present study was to measure frictional resistance between silver coated brackets and different types of arch wires, and shear bond strength of these brackets to the tooth. In an experimental clinical research 28 orthodontic brackets (standard, 22 slots) were coated with silver ions using electroplate method. Six brackets (coated: 3, uncoated: 3) were evaluated with Scanning Electron Microscopy and Atomic Force Microscopy. The amount of friction in 15 coated brackets was measured with three different kinds of arch wires (0.019 × 0.025-in stainless steel [SS], 0.018-in stainless steel [SS], 0.018-in Nickel-Titanium [Ni-Ti]) and compared with 15 uncoated steel brackets. In addition, shear bond strength values were compared between 10 brackets with silver coating and 10 regular brackets. Universal testing machine was used to measure shear bond strength and the amount of friction between the wires and brackets. SPSS 18 was used for data analysis with t-test. SEM and AFM results showed deposition of a uniform layer of silver, measuring 8-10 μm in thickness on bracket surfaces. Silver coating led to higher frictional forces in all the three types of arch wires, which was statistically significant in 0.019 × 0.025-in SS and 0.018-in Ni-Ti, but it did not change the shear bond strength significantly. Silver coating with electroplating method did not affect the bond strength of the bracket to enamel; in addition, it was not an effective method for decreasing friction in sliding mechanics. © Wiley Periodicals, Inc.

  1. Impairment of resin cement application on the bond strength of indirect composite restorations

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    Jovito Adiel SKUPIEN

    2015-01-01

    Full Text Available The aims of this study were to evaluate the effect of immediate and delayed resin cement application on the microtensile bond strength of indirect composite resin restorations and, to evaluate adhesive strategies (for regular resin cement or humidity parameters for self-adhesive resin cement. Forty-five enamel/dentin discs (0.5 mm height and 10 mm of diameter obtained from bovine teeth were divided into nine groups (n = 5. For regular cement, the variation factors were cementation technique at three levels (immediate cementation, 5 or 30 min after adhesive system application; and type of adhesive system at two levels (three- or two-step. For self-adhesive cement, the dentin moisture was the source of variation at three levels (normal, dry, or wet cementation. The specimens were submitted to microtensile bond strength (μTBS testing using a universal testing machine. Data were analyzed by ANOVA, Tukey’s test, and linear regression. Regular cement and three-step etch-and-rinse adhesive system showed the highest values of bond strength (25.21 MPa–30 min of delay. Only for this condition, three-step adhesive showed higher bond strength than the two-step adhesive. Nevertheless, the linear regression showed that irrespective of the strategy, the use of the two-step approach when compared with three-step adhesive system decreased μTBS (p < 0.001. The failure analysis showed predominant adhesive failures for all tested groups. All groups had comparable values of bond strength to bovine dentin when the same materials were used, even in suboptimal clinical conditions.

  2. Repair bond strength of nanohybrid composite resins with a universal adhesive.

    Science.gov (United States)

    Altinci, Pinar; Mutluay, Murat; Tezvergil-Mutluay, Arzu

    2018-01-01

    Objective: To investigate the repair bond strength of fresh and aged nanohybrid and hybrid composite resins using a universal adhesive (UA). Materials and methods: Fresh and aged substrates were prepared using two nanohybrid (Venus Pearl, Heraus Kulzer; Filtek Supreme XTE, 3 M ESPE) and one hybrid (Z100, 3 M ESPE) composite resin, and randomly assigned to different surface treatments: (1) no treatment (control), (2) surface roughening with 320-grit (SR), (3) SR + UA (iBOND, Heraus Kulzer), (4) SR + Silane (Signum, Ceramic Bond I, Heraeus Kulzer) + UA, (5) SR + Sandblasting (CoJet, 3 M ESPE) + Silane + UA. After surface treatment, fresh composite resin was added to the substrates at 2 mm layer increments to a height of 5 mm, and light cured. Restored specimens were water-stored for 24 h and sectioned to obtain 1.0 × 1.0 mm beams ( n  = 12), and were either water-stored for 24 h at 37 °C, or water-stored for 24 h, and then thermocycled for 6000 cycles before microtensile bond strength (µTBS) testing. Data were analyzed with ANOVA and Tukey's HSD tests ( p  = .05). Results: Combined treatment of SR, sandblasting, silane and UA provided repair bond strength values comparable to the cohesive strength of each tested resin material ( p  composite resins upto 65% ( p  composite repair. Sandblasting and silane application slightly increases the repair strength for all substrate types.

  3. Ceramic Inlays: Effect of Mechanical Cycling and Ceramic Type on Restoration-dentin Bond Strength.

    Science.gov (United States)

    Trindade, F Z; Kleverlaan, C J; da Silva, L H; Feilzer, A J; Cesar, P F; Bottino, M A; Valandro, L F

    2016-01-01

    This study aimed to evaluate the bond strength between dentin and five different ceramic inlays in permanent maxillary premolars, with and without mechanical cycling. One hundred permanent maxillary premolars were prepared and divided into 10 groups (n=10) according to the ceramic system (IPS e.Max Press; IPS e.Max CAD; Vita PM9; Vita Mark II; and Vita VM7) and the mechanical cycling factor (with and without [100 N, 2 Hz, 1.2×10(6) cycles]). The inlays were adhesively cemented, and all of the specimens were cut into microbars (1×1 mm, nontrimming method), which were tested under microtensile loading. The failure mode was classified and contact angle, roughness, and microtopographic analyses were performed on each ceramic surface. The mechanical cycling had a significant effect (p=0.0087) on the bond strength between dentin and IPS e.max Press. The Vita Mark II group had the highest bond strength values under both conditions, with mechanical cycling (9.7±1.8 MPa) and without (8.2±1.9 MPa), while IPS e.Max CAD had the lowest values (2.6±1.6 and 2.2±1.4, respectively). The adhesive failure mode at the ceramic/cement interface was the most frequent. Vita Mark II showed the highest value of average roughness. IPS e.max Press and Vita Mark II ceramics presented the lowest contact angles. In conclusion, the composition and manufacturing process of ceramics seem to have an influence on the ceramic surface and resin cement bond strength. Mechanical cycling did not cause significant degradation on the dentin and ceramic bond strength under the configuration used.

  4. Relationships among the structural topology, bond strength, and mechanical properties of single-walled aluminosilicate nanotubes.

    Science.gov (United States)

    Liou, Kai-Hsin; Tsou, Nien-Ti; Kang, Dun-Yen

    2015-10-21

    Carbon nanotubes (CNTs) are regarded as small but strong due to their nanoscale microstructure and high mechanical strength (Young's modulus exceeds 1000 GPa). A longstanding question has been whether there exist other nanotube materials with mechanical properties as good as those of CNTs. In this study, we investigated the mechanical properties of single-walled aluminosilicate nanotubes (AlSiNTs) using a multiscale computational method and then conducted a comparison with single-walled carbon nanotubes (SWCNTs). By comparing the potential energy estimated from molecular and macroscopic material mechanics, we were able to model the chemical bonds as beam elements for the nanoscale continuum modeling. This method allowed for simulated mechanical tests (tensile, bending, and torsion) with minimum computational resources for deducing their Young's modulus and shear modulus. The proposed approach also enabled the creation of hypothetical nanotubes to elucidate the relative contributions of bond strength and nanotube structural topology to overall nanotube mechanical strength. Our results indicated that it is the structural topology rather than bond strength that dominates the mechanical properties of the nanotubes. Finally, we investigated the relationship between the structural topology and the mechanical properties by analyzing the von Mises stress distribution in the nanotubes. The proposed methodology proved effective in rationalizing differences in the mechanical properties of AlSiNTs and SWCNTs. Furthermore, this approach could be applied to the exploration of new high-strength nanotube materials.

  5. Effects of mechanical and thermal load cycling on micro tensile bond strength of clearfil SE bond to superficial dentin

    Directory of Open Access Journals (Sweden)

    Ali Reza Daneshkazemi

    2013-01-01

    Full Text Available Background: Certain studies have been conducted on the effects of mechanical and thermal load cycling on the microtensile bond strength (microTBS of composites to dentin, but the results were different. The authors therefore decided to evaluate these effects on the bonding of Clearfil SE bond to superficial dentin. Materials and Methods: Flat dentinal surface of 42 molar teeth were bonded to Filtek-Z250 resin composite by Clearfil SE bond. The teeth were randomly divided into 7 groups and exposed to different mechanical and thermal load cycling. Thermocycling was at 5-55°C and mechanical load cycling was created with a force of 125 N and 0.5 Hz. Then, the teeth were sectioned and shaped to hour glass form and subjected to microTBS testing at a speed of 0.5 mm/min. The results were statistically analyzed by computer with three-way analysis of variance and T-test at P < 0.05 significant. To evaluate the location and mode of failure, the specimens were observed under the stereomicroscope. Then, one of the specimens in each group was evaluated under Scanning Electron Microscopy (SEM for mode of failure. Results: All of the study groups had a significantly lower microTBS as compared to the control group ( P < 0.001. There was no statistically significant difference between mechanical cycling with 50K (kilo = 1000 cycles, and 50K mechanical cycles plus 1K thermal cycles. Most of the fractures in the control group were of adhesive type and this type of fracture increased after exposure to mechanical and thermal load cycling. Conclusion: Thermal and mechanical load cycling had significant negative effects on microTBS and the significant effects of mechanical load cycling started to be significant at 100K cycles.

  6. Effect of simulated pulpal pressure on all-in-one adhesive bond strengths to dentine.

    Science.gov (United States)

    Hosaka, Keiichi; Nakajima, Masatoshi; Yamauti, Monica; Aksornmuang, Juthatip; Ikeda, Masaomi; Foxton, Richard M; Pashley, David H; Tagami, Junji

    2007-03-01

    To evaluate the durability of all-in-one adhesive systems bonded to dentine with and without simulated hydrostatic pulpal pressure (PP). Flat dentine surfaces of extracted human molars were prepared. Two all-in-one adhesive systems, One-Up Bond F (OBF) (Tokuyama Corp., Tokyo, Japan), and Fluoro Bond Shake One (FBS) (Shofu Co., Kyoto, Japan) were applied to the dentine surfaces under either a PP of 0 or 15cm H(2)O. Then, resin composite build-ups were made. The specimens bonded under pressure were stored in 37 degrees C water for 24h, 1 and 3 months under 15cm H(2)O PP. Specimens not bonded under pressure were stored under zero PP. After storage, the specimens were sectioned into slabs that were trimmed to hourglass shapes and subjected to micro-tensile bond testing (muTBS). The data were analysed using two-way ANOVA and Holm-Sidak HSD multiple comparison tests (alpha=0.05). The muTBS of OBF fell significantly (phydrostatic pressure storage fell significantly over the 3 months period, the decrease was less than half as much as specimens stored under PP. In FBS bonded specimens, although there was no significant difference between the muTBS with and without hydrostatic pulpal pressure at 24h, by 1 and 3 months of storage under PP, significant reductions were seen compared with the control group without PP. The muTBS of OBF bonded specimens was lowered more by simulated PP than by storage time; specimens bonded with FBS were not sensitive to storage time in the absence of PP, but showed lower bond strengths at 1 and 3 months in the presence of PP.

  7. The effect of dentine surface preparation and reduced application time of adhesive on bonding strength.

    Science.gov (United States)

    Saikaew, Pipop; Chowdhury, A F M Almas; Fukuyama, Mai; Kakuda, Shinichi; Carvalho, Ricardo M; Sano, Hidehiko

    2016-04-01

    This study evaluated the effects of surface preparation and the application time of adhesives on the resin-dentine bond strengths with universal adhesives. Sixty molars were cut to exposed mid-coronal dentine and divided into 12 groups (n=5) based on three factors; (1) adhesive: G-Premio Bond (GP, GC Corp., Tokyo, Japan), Clearfil Universal Bond (CU, Kuraray Noritake Dental Inc., Okayama, Japan) and Scotchbond Universal Adhesive (SB, 3M ESPE, St. Paul, MN, USA); (2) smear layer preparation: SiC paper ground dentine or bur-cut dentine; (3) application time: shortened time or as manufacturer's instruction. Fifteen resin-dentine sticks per group were processed for microtensile bond strength test (μTBS) according to non-trimming technique (1mm(2)) after storage in distilled water (37 °C) for 24h. Data were analyzed by three-way ANOVA and Dunnett T3 tests (α=0.05). Fractured surfaces were observed under scanning electron microscope (SEM). Another 12 teeth were prepared and cut into slices for SEM examination of bonded interfaces. μTBS were higher when bonded to SiC-ground dentine according to manufacturer's instruction. Bonding to bur-cut dentine resulted in significantly lower μTBS (padhesive resin interface. This was more pronounced when adhesives were bonded with a reduced application time and on bur cut dentine. The performance of universal adhesives can be compromised on bur cut dentine and when applied with a reduced application time. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. In vitro shear bond strength of cementing agents to fixed prosthodontic restorative materials.

    Science.gov (United States)

    Piwowarczyk, Andree; Lauer, Hans-Christoph; Sorensen, John A

    2004-09-01

    Durable bonding to fixed prosthodontic restorations is desirable; however, little information is available on the strength of the bond between different cements and fixed prosthodontic restorative materials. This study determined the shear-bond strength of cementing agents to high-gold-content alloy castings and different dental ceramics: high-strength aluminum oxide (Procera AllCeram), leucite-reinforced (IPS Empress), and lithium disilicate glass-ceramic (IPS Empress 2). Prepolymerized resin composite cylinders (5.5 mm internal diameter, n=20) were bonded to the pretreated surfaces of prosthodontic materials. High-gold-content alloy and high-strength aluminum oxide surfaces were airborne-particle-abraded, and pressable ceramics were hydrofluoric acid-etched and silanized prior to cementing. The cementing agents tested were a zinc-phosphate cement (Fleck's zinc cement), glass ionomer cements (Fuji I, Ketac-Cem), resin-modified glass ionomer cements (Fuji Plus, Fuji Cem, RelyX Luting), resin cements (RelyX ARC, Panavia F, Variolink II, Compolute), and a self-adhesive universal resin cement (RelyX Unicem). Half the specimens (n=10) were tested after 30 minutes; the other half (n=10) were stored in distilled water at 37 degrees C for 14 days and then thermal cycled 1000 times between 5 degrees C and 55 degrees C prior to testing. Shear-bond strength tests were performed using a universal testing machine at a constant crosshead speed of 0.5 mm/min. Statistical analysis was performed by multifactorial analysis of variance taking interactions between effects into account. For multiple paired comparisons, the Tukey method was used (alpha=.05). In a 3-way ANOVA model, the main factors substrate, cement, time, and all corresponding interactions were statistically significant (all P <.0001). In subsequent separate 1-way or 2-way ANOVA models for each substrate type, significant differences between cement types and polymerizing modes were found (all P <.001). None of the

  9. Effect of three porcelain etchants type (HF-APF-PHA on porcelain- composite shear bond strength

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    Kermanshah H.

    2005-05-01

    Full Text Available Statement of Problem: Porcelain restorations are susceptible to fracture and a common method for repairing is the use of silane and composite on etched porcelain. Although HF is very effective in porcelain etching but has detrimental effects on tissues. Purpose: In this study, the effect of APF and PHA was compared with HF in porcelain etching. Also the role of silane, unfilled resin and dentin bonding in bond strength of composite- porcelain was evaluated. Methods and Materials: In this experimental in-vitro study, one-hundred twenty porcelain square blocks (552 mm were prepared and bonding surfaces of each sandblasted. Samples were divided into three groups. The first group (n=40 were etched with buffered HF 9.5% (Ultradent for 1 min., the second group (n=40 were etched with Iranian APF 1.23% (Kimia for 10 minutes and the third group (n=40 were etched with Iranian PHA 37% (Kimia for 1 min. Ultradent silane was applied on the surfaces of half of cases in each group. On the surfaces of half of silane-treated samples unfilled resin was applied and dentin bonding was used on the surfaces of the remaining. Samples without silane were treated in a similar manner. Composite cylinder with 4mm diameter and 2 mm height was bonded to porcelain. Specimens were stored in 37°C distilled water for 24 hours and subjected to 500 cycles. Shear bond strength was measured with an Instron machine and type of fracture was evaluated using a stereomicroscope. Results were analyzed using 3 way ANOVA, Kaplan- Maier and Tukey HSD tests. Results: Findings showed that PHA and APF roughened the porcelain surface without creating retentive micro undercuts but HF etches porcelain and creates retentive microundercuts. Ultradent silane had no significant effect on bond strength of porcelain- composite. Unfilled resin with Ultradent silane compared with dentin bonding with the same silane is more effective in bond strength of composite- porcelain. Conclusion: Based on

  10. Shear bond strength of a denture base acrylic resin and gingiva-colored indirect composite material to zirconia ceramics.

    Science.gov (United States)

    Kubochi, Kei; Komine, Futoshi; Fushiki, Ryosuke; Yagawa, Shogo; Mori, Serina; Matsumura, Hideo

    2017-04-01

    To evaluate the shear bond strengths of two gingiva-colored materials (an indirect composite material and a denture base acrylic resin) to zirconia ceramics and determine the effects of surface treatment with various priming agents. A gingiva-colored indirect composite material (CER) or denture base acrylic resin (PAL) was bonded to zirconia disks with unpriming (UP) or one of seven priming agents (n=11 each), namely, Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Act), Metal Link (MEL), Meta Fast Bonding Liner (MFB), MR. bond (MRB), and V-Primer (VPR). Shear bond strength was determined before and after 5000 thermocycles. The data were analyzed with the Kruskal-Wallis test and Steel-Dwass test. The mean pre-/post-thermalcycling bond strengths were 1.0-14.1MPa/0.1-12.1MPa for the CER specimen and 0.9-30.2MPa/0.1-11.1MPa for the PAL specimen. For the CER specimen, the ALP, CPB, and CPB+Act groups had significantly higher bond strengths among the eight groups, at both 0 and 5000 thermocycles. For the PAL specimen, shear bond strength was significantly lower after thermalcycling in all groups tested. After 5000 thermocycles, bond strengths were significantly higher in the CPB and CPB+Act groups than in the other groups. For the PAL specimens, bond strengths were significantly lower after thermalcycling in all groups tested. The MDP functional monomer improved bonding of a gingiva-colored indirect composite material and denture base acrylic resin to zirconia ceramics. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  11. [Evaluation of shear bond strengths of self-etching and total-etching dental adhesives to enamel and dentin].

    Science.gov (United States)

    Yu, Ling; Liu, Jing-Ming; Wang, Xiao-Yan; Gao, Xue-Jun

    2009-03-01

    To evaluate the shear bond strengths of four dental adhesives in vitro. The facial surfaces of 20 human maxillary incisors were prepared to expose fresh enamel and randomly divided into four groups, in each group 5 teeth were bonded with one adhesives: group A (Clearfil Protect Bond, self-etching two steps), group B (Adper( Prompt, self-etching one step), group C (SwissTEC SL Bond, total-etching two steps), group D (Single Bond, total-etching two steps). Shear bond strengths were determined using an universal testing machine after being stored in distilled water for 24 h at 37 degrees C. The bond strengths to enamel and dentin were (25.33 +/- 2.84) and (26.07 +/- 5.56) MPa in group A, (17.08 +/- 5.13) and (17.93 +/- 4.70) MPa in group B, (33.14 +/- 6.05) and (41.92 +/- 6.25) MPa in group C, (22.51 +/- 6.25) and (21.45 +/- 7.34) MPa in group D. Group C showed the highest and group B the lowest shear bond strength to enamel and dentin among the four groups. The two-step self-etching adhesive showed comparable shear bond strength to some of the total-etching adhesives and higher shear bond strength than one-step self-etching adhesive.

  12. Effect of Surface Treatment on Shear Bond Strength between Resin Cement and Ce-TZP/Al2O3

    Directory of Open Access Journals (Sweden)

    Jong-Eun Kim

    2016-01-01

    Full Text Available Purpose. Although several studies evaluating the mechanical properties of Ce-TZP/Al2O3 have been published, to date, no study has been published investigating the bonding protocol between Ce-TZP/Al2O3 and resin cement. The aim of this study was to evaluate the shear bond strength to air-abraded Ce-TZP/Al2O3 when primers and two different cement types were used. Materials and Methods. Two types of zirconia (Y-TZP and Ce-TZP/Al2O3 specimens were further divided into four subgroups according to primer application and the cement used. Shear bond strength was measured after water storage for 3 days or 5,000 times thermocycling for artificial aging. Results. The Y-TZP block showed significantly higher shear bond strength than the Ce-TZP/Al2O3 block generally. Primer application promoted high bond strength and less effect on bond strength reduction after thermocycling, regardless of the type of cement, zirconia block, or aging time. Conclusions. Depending on the type of the primer or resin cement used after air-abrasion, different wettability of the zirconia surface can be observed. Application of primer affected the values of shear bond strength after the thermocycling procedure. In the case of using the same bonding protocol, Y-TZP could obtain significantly higher bond strength compared with Ce-TZP/Al2O3.

  13. Effect of ultraviolet light irradiation and sandblasting treatment on bond strengths between polyamide and chemical-cured resin.

    Science.gov (United States)

    Asakawa, Yuya; Takahashi, Hidekazu; Iwasaki, Naohiko; Kobayashi, Masahiro

    2014-01-01

    The aim of this study was to evaluate the effects of ultraviolet light (UV) irradiation and sandblasting treatment on the shear bond strength between polyamide and chemical-cured resin. Three types of commercial polyamides were treated using UV irradiation, sandblasting treatment, and a combining sandblasting and UV irradiation. The shear bond strength was measured and analyzed using the Kruskal-Wallis test (α=0.05). Comparing shear bond strengths without surface treatment, from 4.1 to 5.7 MPa, the UV irradiation significantly increased the shear bond strengths except for Valplast, whose shear bond strengths ranged from 5.2 to 9.3 MPa. The sandblasting treatment also significantly increased the shear bond strengths (8.0 to 11.4 MPa). The combining sandblasting and UV irradiation significantly increased the shear bond strengths (15.2 to 18.3 MPa) comparing without surface treatment. This combined treatment was considered the most effective at improving the shear bond strength between polyamide and chemical-cured resin.

  14. Effects of solvent volatilization time on the bond strength of etch-and-rinse adhesive to dentin using conventional or deproteinization bonding techniques.

    Science.gov (United States)

    de Sousa Júnior, José Aginaldo; Carregosa Santana, Márcia Luciana; de Figueiredo, Fabricio Eneas Diniz; Faria-E-Silva, André Luis

    2015-08-01

    This study determined the effect of the air-stream application time and the bonding technique on the dentin bond strength of adhesives with different solvents. Furthermore, the content and volatilization rate of the solvents contained in the adhesives were also evaluated. Three adhesive systems with different solvents (Stae, SDI, acetone; XP Bond, Dentsply De Trey, butanol; Ambar, FGM, ethanol) were evaluated. The concentrations and evaporation rates of each adhesive were measured using an analytical balance. After acid-etching and rinsing, medium occlusal dentin surfaces of human molars were kept moist (conventional) or were treated with 10% sodium hypochlorite for deproteinization. After applying adhesives over the dentin, slight air-stream was applied for 10, 30 or 60 sec. Composite cylinders were built up and submitted to shear testing. The data were submitted to ANOVA and Tukey's test (α = 0.05). Stae showed the highest solvent content and Ambar the lowest. Acetone presented the highest evaporation rate, followed by butanol. Shear bond strengths were significantly affected only by the factors of 'adhesive' and 'bonding technique' (p Stae showed the lowest bond strength values (p < 0.05), while no significant difference was observed between XP Bond and Ambar. Despite the differences in content and evaporation rate of the solvents, the duration of air-stream application did not affect the bond strength to dentin irrespective of the bonding technique.

  15. Effects of Hybrid Coat on shear bond strength of five cements: an in vitro study.

    Science.gov (United States)

    Guo, Yue; Zhou, Hou-De; Feng, Yun-Zhi

    2017-12-01

    To evaluate the sealing performance of Hybrid Coat and its influence on the shear bond strength of five dentin surface cements. 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 astereomicroscope. 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). 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.

  16. Bond strength to dentin with artificial carious lesions: influence of caries detecting dye.

    Science.gov (United States)

    Palma, R G; Turbino, M L; Matson, E; Powers, J M

    1998-06-01

    To evaluate the influence of dyes for caries detection on tensile bond strength of adhesive materials to artificial carious dentin. Buccal and lingual enamel of human molars were removed leaving intact dentin surfaces. The entire surface of each specimen was covered with nail varnish, keeping a window area of 4 x 4 mm. Artificial carious lesions were induced with acidified gel. Three dyes (0.5% basic fuchsin; Caries Finder and Cari-D-Tect) were used according to manufacturers' recommendations. Specimens were etched with 35% phosphoric acid for 20 s, washed and dried, leaving a wet dentin surface. The adhesive system (Prime & Bond 2.0) was applied in two layers and light-cured. Restorative materials (TPH Spectrum, Dyract, Advance) were bonded using a 3-mm diameter inverted-cone mold. Control groups were made without dye. Eight samples were tested for each group. After 24 hrs of storage in distilled water, the samples were debonded using a testing machine at 0.5 mm/min crosshead speed. ANOVA and Tukey-Kramer test showed that TPH Spectrum (0.73 MPa) and Dyract (0.74 MPa) had similar bond strengths, and both were higher than Advance (0.0 MPa), which was statistically different (P strength for any tested materials.

  17. Environment-friendly wood fibre composite with high bonding strength and water resistance

    Science.gov (United States)

    Ji, Xiaodi; Dong, Yue; Nguyen, Tat Thang; Chen, Xueqi; Guo, Minghui

    2018-04-01

    With the growing depletion of wood-based materials and concerns over emissions of formaldehyde from traditional wood fibre composites, there is a desire for environment-friendly binders. Herein, we report a green wood fibre composite with specific bonding strength and water resistance that is superior to a commercial system by using wood fibres and chitosan-based adhesives. When the mass ratio of solid content in the adhesive and absolute dry wood fibres was 3%, the bonding strength and water resistance of the wood fibre composite reached the optimal level, which was significantly improved over that of wood fibre composites without adhesive and completely met the requirements of the Chinese national standard GB/T 11718-2009. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) characterizations revealed that the excellent performance of the binder might partly be due to the amide linkages and hydrogen bonding between wood fibres and the chitosan-based adhesive. We believe that this strategy could open new insights into the design of environment-friendly wood fibre composites with high bonding strength and water resistance for multifunctional applications.

  18. Micro-shear bond strength of resin cement to dentin after application of desensitizing toothpastes.

    Science.gov (United States)

    Bavbek, Andac Barkin; Goktas, Baris; Cekic-Nagas, Isil; Egilmez, Ferhan; Ergun, Gulfem; Eskitascioglu, Gurcan

    2013-01-01

    The aim of the study was to evaluate the effect of three desensitizing toothpastes on bonding of resin cements to dentin. The occlusal surfaces of 72 maxillary third molars were ground to obtain flat dentin surfaces and then divided into three groups according to three desensitizing toothpastes used: Sensodyne Rapid Relief (GlaxoSmithKline, SmithKline Beecham Ltd., Slough, UK), Signal Sensitive Expert (Unilever Sanayi ve Ticaret Türk A.Ş., Ümraniye, İstanbul, Turkey) and Colgate Sensitive Pro-Relief (Colgate Palmolive, New York, NY). Following bonding of the resin cement (Clearfil™ SA Cement, Kuraray Co, Osaka, Japan) to dentin, the specimens were light cured for 40 s with a LED (Elipar S10, 3M Espe, St. Paul, MN). The strength measurements were accomplished with a micro-shear testing machine (Bisco, Schaumburg, IL) at a cross-head speed of 0.5 mm/min until the failure occurs. Failure modes were examined using a stereomicroscope and scanning electron microscope. The data were analyzed with one-way analysis of variance (ANOVA) and Tukey HSD test (α = 0.05). ANOVA revealed that the application of desensitizing toothpastes had significant effects on bond strength of the resin cement tested to dentin (p < 0.05). Mixed failures were observed in all of the groups. The use of a desensitizing toothpaste before cementation might alter the bond strength of adhesively luted restorations.

  19. The Strength of Hydrogen Bonds between Fluoro-Organics and Alcohols, a Theoretical Study.

    Science.gov (United States)

    Rosenberg, Robert E

    2018-05-10

    Fluorinated organic compounds are ubiquitous in the pharmaceutical and agricultural industries. To better discern the mode of action of these compounds, it is critical to understand the strengths of hydrogen bonds involving fluorine. There are only a few published examples of the strengths of these bonds. This study provides a high level ab initio study of inter- and intramolecular hydrogen bonds between RF and R'OH, where R and R' are aryl, vinyl, alkyl, and cycloalkyl. Intermolecular binding energies average near 5 kcal/mol, while intramolecular binding energies average about 3 kcal/mol. Inclusion of zero-point energies and applying a counterpoise correction lessen the difference. In both series, modest increases in binding energies are seen with increased acidity of R'OH and increased electron donation of R in RF. In the intramolecular compounds, binding energy increases with the rigidity of the F-(C) n -OH ring. Inclusion of free energy corrections at 298 K results in exoergic binding energies for the intramolecular compounds and endoergic binding energies for the intermolecular compounds. Parameters such as bond lengths, vibrational frequencies, and atomic populations are consistent with formation of a hydrogen bond and with slightly stronger binding in the intermolecular cases over the intramolecular cases. However, these parameters correlated poorly with binding energies.

  20. Hybridization quality and bond strength of adhesive systems according to interaction with dentin

    Science.gov (United States)

    Salvio, Luciana Andrea; Hipólito, Vinicius Di; Martins, Adriano Luis; de Goes, Mario Fernando

    2013-01-01

    Objective: To evaluate the hybridization quality and bond strength of adhesives to dentin. Materials and Methods: Ten human molars were ground to expose the dentin and then sectioned in four tooth-quarters. They were randomly divided into 5 groups according to the adhesive used: Two single-step self-etch adhesives – Adper Prompt (ADP) and Xeno III (XE), two two-step self-etching primer systems – Clearfil SE Bond (SE) and Adhe SE (ADSE), and one one-step etch-and-rinse system – Adper Single Bond (SB). Resin composite (Filtek Z250) crown buildups were made on the bonded surfaces and incrementally light-cured for 20 s. The restored tooth-quarters were stored in water at 37°C for 24 h and then sectioned into beams (0.8 mm2 in cross-section). Maximal microtensile bond strength (μ-TBS) was recorded (0.5 mm/min in crosshead speed). The results were submitted to one-way ANOVA and Tukey's test (α = 0.05). Thirty additional teeth were used to investigate the hybridization quality by SEM using silver methenamine or ammoniacal silver nitrate dyes. Results: SE reached significantly higher μ-TBS (P 0.05), and between SB and ADP (P > 0.05); ADSE and XE were significantly higher than SB and ADP (P adhesives with dentin. The hybridization quality was essential to improve the immediate μ-TBS to dentin. PMID:24926212

  1. Effect of Dentin Wetness on the Bond Strength of Universal Adhesives

    Science.gov (United States)

    Lee, Ji-Hye; Son, Sung-Ae; Jung, Kyoung-Hwa; Kwon, Yong Hoon

    2017-01-01

    The effects of dentin wetness on the bond strength and adhesive interface morphology of universal adhesives have been investigated using micro-tensile bond strength (μTBS) testing and confocal laser scanning microscopy (CLSM). Seventy-two human third molars were wet ground to expose flat dentin surfaces. They were divided into three groups according to the air-drying time of the dentin surfaces: 0 (without air drying), 5, and 10 s. The dentin surfaces were then treated with three universal adhesives: G-Premio Bond, Single Bond Universal, and All-Bond Universal in self-etch or etch-and-rinse mode. After composite build up, a μTBS test was performed. One additional tooth was prepared for each group by staining the adhesives with 0.01 wt % of Rhodamine B fluorescent dye for CLSM analysis. The data were analyzed statistically using ANOVA and Tukey’s post hoc tests (α = 0.05). Two-way ANOVA showed significant differences among the adhesive systems and dentin moisture conditions. An interaction effect was also observed (p adhesives. PMID:29068404

  2. Does the casting mode influence microstructure, fracture and properties of different metal ceramic alloys?

    Science.gov (United States)

    Bauer, José Roberto de Oliveira; Grande, Rosa Helena Miranda; Rodrigues-Filho, Leonardo Eloy; Pinto, Marcelo Mendes; Loguercio, Alessandro Dourado

    2012-01-01

    The aim of the present study was to evaluate the tensile strength, elongation, microhardness, microstructure and fracture pattern of various metal ceramic alloys cast under different casting conditions. Two Ni-Cr alloys, Co-Cr and Pd-Ag were used. The casting conditions were as follows: electromagnetic induction under argon atmosphere, vacuum, using blowtorch without atmosphere control. For each condition, 16 specimens, each measuring 25 mm long and 2.5 mm in diameter, were obtained. Ultimate tensile strength (UTS) and elongation (EL) tests were performed using a Kratos machine. Vickers Microhardness (VM), fracture mode and microstructure were analyzed by SEM. UTS, EL and VM data were statistically analyzed using ANOVA. For UTS, alloy composition had a direct influence on casting condition of alloys (Wiron 99 and Remanium CD), with higher values shown when cast with Flame/Air (p casting condition" influenced the EL and VM results, generally presenting opposite results, i.e., alloy with high elongation value had lower hardness (Wiron 99), and casting condition with the lowest EL values had the highest VM values (blowtorch). Both factors had significant influence on the properties evaluated, and prosthetic laboratories should select the appropriate casting method for each alloy composition to obtain the desired property.

  3. Hybridization quality and bond strength of adhesive systems according to interaction with dentin.

    Science.gov (United States)

    Salvio, Luciana Andrea; Hipólito, Vinicius Di; Martins, Adriano Luis; de Goes, Mario Fernando

    2013-07-01

    To evaluate the hybridization quality and bond strength of adhesives to dentin. Ten human molars were ground to expose the dentin and then sectioned in four tooth-quarters. They were randomly divided into 5 groups according to the adhesive used: Two single-step self-etch adhesives - Adper Prompt (ADP) and Xeno III (XE), two two-step self-etching primer systems - Clearfil SE Bond (SE) and Adhe SE (ADSE), and one one-step etch-and-rinse system - Adper Single Bond (SB). Resin composite (Filtek Z250) crown buildups were made on the bonded surfaces and incrementally light-cured for 20 s. The restored tooth-quarters were stored in water at 37°C for 24 h and then sectioned into beams (0.8 mm(2) in cross-section). Maximal microtensile bond strength (μ-TBS) was recorded (0.5 mm/min in crosshead speed). The results were submitted to one-way ANOVA and Tukey's test (α = 0.05). Thirty additional teeth were used to investigate the hybridization quality by SEM using silver methenamine or ammoniacal silver nitrate dyes. SE reached significantly higher μ-TBS (P 0.05), and between SB and ADP (P > 0.05); ADSE and XE were significantly higher than SB and ADP (P quality than that observed for ADP and XE. The bond strength and hybridization quality were affected by the interaction form of the adhesives with dentin. The hybridization quality was essential to improve the immediate μ-TBS to dentin.

  4. Effect of dentin pretreatment with potassium oxalate: analysis of microtensile bond strengths and morphologic aspects.

    Science.gov (United States)

    De Moraes Porto, Isabel Cristina Celerino; De Andrade, Ana Karina Maciel; Alves, Luiz Carlos; Braz, Rodivan

    2012-02-01

    An effective and stable bond is the most desirable characteristic of contemporary adhesive systems. The aim of this study was to evaluate the effect of potassium oxalate on dentin/resin bond strength. Dentin on the occlusal surface of human premolars was exposed and etched with 35% phosphoric acid, to receive 3% monohydrated potassium oxalate and the following adhesive systems: Scotchbond Multipurpose (SMO; 3M/ESPE) and Prime & Bond NT (PBO; Dentsply), followed by the application of resin composite (Z250; 3M/ESPE). The control groups (SM and PB) did not receive potassium oxalate application. The prepared teeth were kept in distilled water at 37°C for 24 h and 12 months. They were then cut longitudinally into sticks with a bond area of ∼0.8 mm(2) for submission to the microtensile bond strength test. The data were analyzed by two-factor ANOVA, Tamhane's paired comparisons, and the Student t-test (α = 0.05). The hybrid layer formed was observed by scanning electron microscopy (SEM). SEM analysis of the surfaces treated with PB revealed shorter resin tags associated with the application of potassium oxalate, whereas SM showed tags similar to those without potassium oxalate. A significant difference was shown between the two storage times for each of the protocols. There was a significant difference among SMO, SM, and PBO (24 h), as well as among SM, SMO, and PBO, and between PB and PBO (12 months). The application of potassium oxalate before conventional adhesive systems may result in alteration of the bond strength between dentin and resin composite, depending on the material. Copyright © 2011 Wiley Periodicals, Inc.

  5. Efficacy of ceramic repair material on the bond strength of composite resin to zirconia ceramic.

    Science.gov (United States)

    Kirmali, Omer; Kapdan, Alper; Harorli, Osman Tolga; Barutcugil, Cagatay; Ozarslan, Mehmet Mustafa

    2015-01-01

    The aim of this study was to evaluate the shear bond strength of composite resin in five different repair systems. Sixty specimens (7 mm in diameter and 3 mm in height) of zirconia ceramic were fabricated. All specimen surfaces were prepared with a 30 µm fine diamond rotary cutting instrument with water irrigation for 10 s and dried with oil-free air. Specimens were then randomly divided into six groups for the following different intra-oral repair systems (n = 10): Group 1, control group; Group 2, Cojet system (3M ESPE, Seefeld, Germany); Group 3, Cimara® System (Voco, Cuxhaven, Germany); Group 4, Z-Prime Plus System (Bisco Inc., Schaumburg, IL); Group 5, Clearfil™ System (Kuraray, Osaka, Japan); and Group 6, Z-Bond System (Danville, CA). After surface conditioning, a composite resin Grandio (Voco, Cuxhaven, Germany) was applied to the zirconia surface using a cylindrical mold (5 mm in diameter and 3 mm in length) and incrementally filled up, according to the manufacturer's instructions of each intra-oral system. Each specimen was subjected to a shear load at a crosshead speed of 1 mm/min until fracture. One-way analysis of variance (ANOVA) and Tukey post-hoc tests were used to analyze the bond strength values. There were significant differences between Groups 2-6 and Group 1. The highest bond strength values were obtained with Group 2 (17.26 ± 3.22) and Group 3 (17.31 ± 3.62), while the lowest values were observed with Group 1 (8.96 ± 1.62) and Group 6 (12.85 ± 3.95). All repair systems tested increased the bond strength values between zirconia and composite resin that used surface grinding with a diamond bur.

  6. Shear bond strength and fracture analysis of human vs. bovine teeth.

    Directory of Open Access Journals (Sweden)

    Stefan Rüttermann

    Full Text Available PURPOSE: To evaluate if bovine enamel and dentin are appropriate substitutes for the respective human hard tooth tissues to test shear bond strength (SBS and fracture analysis. MATERIALS AND METHODS: 80 sound and caries-free human erupted third molars and 80 freshly extracted bovine permanent central incisors (10 specimens for each group were used to investigate enamel and dentine adhesion of one 2-step self-etch (SE and one 3-step etch and rinse (E&R product. To test SBS the buccal or labial areas were ground plane to obtain appropriate enamel or dentine areas. SE and E&R were applied and SBS was measured prior to and after 500 thermocycles between +5 and +55°C. Fracture analysis was performed for all debonded areas. RESULTS: ANOVA revealed significant differences of enamel and dentin SBS prior to and after thermocycling for both of the adhesives. SBS- of E&R-bonded human enamel increased after thermocycling but SE-bonded did not. Bovine enamel SE-bonded showed higher SBS after TC but E&R-bonded had lower SBS. No differences were found for human dentin SE- or E&R-bonded prior to or after thermocycling but bovine dentin SE-bonded increased whereas bovine dentine E&R-bonded decreased. Considering the totalized and adhesive failures, fracture analysis did not show significances between the adhesives or the respective tooth tissues prior to or after thermocycling. CONCLUSION: Although SBS was different on human and bovine teeth, no differences were found for fracture analysis. This indicates that solely conducted SBS on bovine substrate are not sufficient to judge the perfomance of adhesives, thus bovine teeth are questionnable as a substrate for shear bond testing.

  7. Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments

    Directory of Open Access Journals (Sweden)

    Adilson Yoshio Furuse

    2007-12-01

    Full Text Available The purpose of this study was to investigate the effect of different surface treatments on shear bond strength of saliva-contaminated resin-resin interfaces. Flat resin surfaces were fabricated. In the control group, no contamination or surface treatment was performed. The resin surfaces of the experimental groups were contaminated with saliva and air-dried, and then submitted to: (G1 rinsing with water and drying; (G2 application of an adhesive system; (G3 rinsing and drying, abrasion with finishing disks, etching and application of adhesive system; (G4 rinsing and drying, etching, application of silane and adhesive system. Resin cylinders were placed over the treated surfaces. The specimens were stored in water or ethanol. Shear bond strength tests were performed and the mode of failure was evaluated. Data were submitted to two-way ANOVA and Dunnett T3 test. Contamination of resin-resin interfaces with saliva significantly reduced shear strength, especially after prolonged storage (p<0.05. Similar values to the original bond strength were obtained after abrasion and application of adhesive (G3 or etching and application of silane and adhesive (G4. If contamination occurs, a surface treatment is required to guarantee an adequate interaction between the resin increments.

  8. Effects of replacement of binder content on bond strength of mortars

    Directory of Open Access Journals (Sweden)

    E. B. C. Costa

    Full Text Available The reduction of binder content in cementitious systems is an effective way to mitigate environmental impacts without increasing costs. The main purpose of this study is to evaluate the effect of content binder on bond strength of mortar-brick interface. For thus, it was studied mortars produced with two limestone fines with different particle size distribution. The limestone fines were added at rates of 0% to 60% at increments of 15% as partial volume replacement of binder. Mortars were prepared in proportion of 1:3 (binder + limestone: sand in volume. The water content was kept constant and equal to 18% in relation to total weight of solids. The mechanical property of mortars was evaluated by tensile strength and the performance of interface by bond strength tests at 14 days. Results indicate that is possible make mortars with 45% less than binder without reducing bond strength. Thus, the use of appropriate particles of limestone can produce more environmentally friendly concrete and rendering mortars by reducing its binder factor without affecting its performance.

  9. Pull-Out Strength and Bond Behavior of Prestressing Strands in Prestressed Self-Consolidating Concrete

    Directory of Open Access Journals (Sweden)

    Wu-Jian Long

    2014-10-01

    Full Text Available With the extensive use of self-consolidating concrete (SCC worldwide, it is important to ensure that such concrete can secure uniform in-situ mechanical properties that are similar to those obtained with properly consolidated concrete of conventional fluidity. Ensuring proper stability of SCC is essential to enhance the uniformity of in-situ mechanical properties, including bond to embedded reinforcement, which is critical for structural engineers considering the specification of SCC for prestressed applications. In this investigation, Six wall elements measuring 1540 mm × 2150 mm × 200 mm were cast using five SCC mixtures and one reference high-performance concrete (HPC of normal consistency to evaluate the uniformity of bond strength between prestressing strands and concrete as well as the distribution of compressive strength obtained from cores along wall elements. The evaluated SCC mixtures used for casting wall elements were proportioned to achieve a slump flow consistency of 680 ± 15 mm and minimum caisson filling capacity of 80%, and visual stability index of 0.5 to 1. Given the spreads in viscosity and static stability of the SCC mixtures, the five wall elements exhibited different levels of homogeneity in in-situ compressive strength and pull-out bond strength. Test results also indicate that despite the high fluidity of SCC, stable concrete can lead to more homogenous in-situ properties than HPC of normal consistency subjected to mechanical vibration.

  10. Pull-Out Strength and Bond Behavior of Prestressing Strands in Prestressed Self-Consolidating Concrete.

    Science.gov (United States)

    Long, Wu-Jian; Khayat, Kamal Henri; Lemieux, Guillaume; Hwang, Soo-Duck; Xing, Feng

    2014-10-10

    With the extensive use of self-consolidating concrete (SCC) worldwide, it is important to ensure that such concrete can secure uniform in-situ mechanical properties that are similar to those obtained with properly consolidated concrete of conventional fluidity. Ensuring proper stability of SCC is essential to enhance the uniformity of in-situ mechanical properties, including bond to embedded reinforcement, which is critical for structural engineers considering the specification of SCC for prestressed applications. In this investigation, Six wall elements measuring 1540 mm × 2150 mm × 200 mm were cast using five SCC mixtures and one reference high-performance concrete (HPC) of normal consistency to evaluate the uniformity of bond strength between prestressing strands and concrete as well as the distribution of compressive strength obtained from cores along wall elements. The evaluated SCC mixtures used for casting wall elements were proportioned to achieve a slump flow consistency of 680 ± 15 mm and minimum caisson filling capacity of 80%, and visual stability index of 0.5 to 1. Given the spreads in viscosity and static stability of the SCC mixtures, the five wall elements exhibited different levels of homogeneity in in-situ compressive strength and pull-out bond strength. Test results also indicate that despite the high fluidity of SCC, stable concrete can lead to more homogenous in-situ properties than HPC of normal consistency subjected to mechanical vibration.

  11. [Bond strengths of absorbable polylactic acid root canal post with three different adhesives].

    Science.gov (United States)

    Pan, Hui; Cheng, Can; Hu, Jia; Liu, He; Sun, Zhi-hui

    2015-12-18

    To find absorbable adhesives with suitable bonding properties for the absorbable polylactic acid root canal post. To test and compare the bond strengths of absorbable polylactic acid root canal post with three different adhesives. The absorbable polylactic acid root canal posts were used to restore the extracted teeth, using 3 different adhesives: cyanoacrylates, fibrin sealant and glass ionomer cement. The teeth were prepared into slices for micro-push-out test. The bond strength was statistically analyzed using ANOVA. The specimens were examined using microscope and the failure mode was divided into four categories: cohesive failure between absorbable polylactic acid root canal posts and adhesives, cohesive failure between dentin and adhesives, failure within the adhesives and failure within the absorbable polylactic acid root canal posts. The bond strength of cyanoacrylates [(16.83 ± 6.97) MPa] and glass ionomer cement [(12.10 ± 5.09) MPa] were significantly higher than fibrin sealant [(1.17 ± 0.50) MPa], Padhesives was 25.0%, the cohesive failure between the dentin and the adhesives was 16.7%, the failure within the adhesives was 33.3%, and the failure within the absorbable polylactic acid root canal posts was 25.0%. In the group of fibrin sealant, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 66.7%, the cohesive failure between the dentin and the adhesives was 22.2%, the failure within the adhesives was 11.1%. In the group of glass ionomer cement, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 87.5%, the failure within the adhesives was 12.5%. The major failure mode in fibrin sealant and glass ionomer cement was the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives. No major failure modes were found in the group of cyanoacrylates. The bond strength of fibrin sealant is low, which cannot meet the requirement of

  12. Resin cements formulated with thio-urethanes can strengthen porcelain and increase bond strength to ceramics.

    Science.gov (United States)

    Bacchi, Atais; Spazzin, Aloisio Oro; de Oliveira, Gabriel Rodrigues; Pfeifer, Carmem; Cesar, Paulo Francisco

    2018-06-01

    The use of thio-urethane oligomers has been shown to significantly improve the mechanical properties of resin cements (RCs). The aim of this study was to use thio-urethane-modified RC to potentially reinforce the porcelain-RC structure and to improve the bond strength to zirconia and lithium disilicate. Six oligomers were synthesized by combining thiols - pentaerythritol tetra-3-mercaptopropionate (PETMP, P) or trimethylol-tris-3-mercaptopropionate (TMP, T) - with di-functional isocyanates - 1,6-Hexanediol-diissocyante (HDDI) (aliphatic, AL) or 1,3-bis(1-isocyanato-1-methylethyl)benzene (BDI) (aromatic, AR) or Dicyclohexylmethane 4,4'-Diisocyanate (HMDI) (cyclic, CC). Thio-urethanes (20 wt%) were added to a BisGMA/UDMA/TEGDMA organic matrix. Filler was introduced at 60 wt%. The microshear bond strength (μSBS), Weibull modulus (m), and failure pattern of RCs bonded to zirconia (ZR) and lithium disilicate (LD) ceramics was evaluated. Biaxial flexural test and fractographic analysis of porcelain discs bonded to RCs were also performed. The biaxial flexural strength (σ bf ) and m were calculated in the tensile surfaces of porcelain and RC structures (Z = 0 and Z = -t 2 , respectively). The μSBS was improved with RCs formulated with oligomers P_AL or T_AL bonded to LD and P_AL, P_AR or T_CC bonded to zirconia in comparison to controls. Mixed failures predominated in all groups. σ bf had superior values at Z = 0 with RCs formulated with oligomers P_AL, P_AR, T_AL, or T_CC in comparison to control; σ bf increased with all RCs composed by thio-urethanes at Z = -t 2 . Fractographic analysis revealed all fracture origins at Z = 0. The use of specific thio-urethane oligomers as components of RCs increased both the biaxial flexural strength of the porcelain-RC structure and the μSBS to LD and ZR. The current investigation suggests that it is possible to reinforce the porcelain-RC pair and obtain higher bond strength to LD and ZR with RCs

  13. Effect of different oxidation treatments on the bonding strength of new dental alloys

    International Nuclear Information System (INIS)

    Lee, Sang-Bae; Lee, Ju-hye; Kim, Woong-Chul; Oh, Sae-Yoon; Kim, Kyoung-Nam; Kim, Ji-Hwan

    2009-01-01

    The influences of heat treatment and addition of a small amount of base metal (In, Sn, and Ir) for oxidation in Au-Pt-based alloy were investigated by electron spectroscopy and scanning electron microscopy. Au-Pt-based alloys were prepared by argon-arc melting furnace and then they are heat treated. Oxidation on alloy was significantly affected by addition of base metal (In and Sn) and heat treatment. The bond strength of the alloys was not dependent on the changing heat treatment. These results indicated that the Sn and In could be effective as oxidation elements for porcelain bonding to gold alloys.

  14. Bond strengths of different orthodontic adhesives after enamel conditioning with the same self-etching primer.

    Science.gov (United States)

    Scougall-Vilchis, Rogelio J; Zárate-Díaz, Chrisel; Kusakabe, Shusuke; Yamamoto, Kohji

    2010-05-01

    To determine the shear bond strengths (SBS) of stainless steel brackets bonded with seven light-cured orthodontic adhesives after the enamel was conditioned with the same self-etching primer. A total of 140 extracted human molars were randomly divided into seven groups (N = 20). In all the groups, the enamel was conditioned with Transbond Plus SEP (TPSEP). Stainless steel brackets were bonded with the following orthodontic adhesives: Group I, Transbond XT; Group II, Blūgloo; Group III, BeautyOrtho Bond; Group IV, Enlight; Group V, Light Bond; Group VI, Transbond CC; Group VII, Xeno Ortho. The teeth were stored in distilled water at 37 degrees C for 24 hours and debonded with a universal testing machine. The modified adhesive remnant index (ARI) was also recorded. There were no significant differences in the SBS values among the groups: I (18.0 +/- 7.4 MPa); II (18.3 +/- 5.1 MPa); III (14.8 +/- 4.3 MPa); IV (18.3 +/- 7.0 MPa); V (16.4 +/- 4.3 MPa); VI (20.3 +/- 5.3 MPa); VII (15.9 +/- 6.4 MPa), but significant differences in ARI were found. The seven orthodontic adhesives evaluated in this study can be successfully used for bonding stainless steel brackets when the enamel is conditioned with TPSEP, however, the differences among some groups might influence the clinical bond strengths. In addition, the amount of residual adhesive remaining on the teeth after debonding differed among the adhesives. Further studies are required to better understand the differences in SBS and ARI.

  15. Effect of Different Saliva Decontamination Procedures on Bond Strength to Dentin in Single Bottle Systems

    Directory of Open Access Journals (Sweden)

    M. Ghavam

    2004-09-01

    Full Text Available Statement of Problem: Following the increasing use of composites in restoring anterior and posterior teeth, problems due to its technique sensitivity have become a major concern.One of these problems is the possibility of contamination of dentin with saliva, blood and/or gingival fluid in different stages of bonding procedure, even with application of different methods of isolation. However, by introduction of Single-bottle dentin adhesives,the contamination possibility reduced to two stages. Scientific documents show that saliva contamination reduces bond strength of composites to dentin. Application of simple and efficient methods for reducing or eliminating saliva contamination enables clinicians to carry out dental treatment without any concern about deterioration of clinical longevity of restoration.Purpose: This study was designed to compare the effect of different decontamination methods on the shear bond strength of composite to dentin using a “Single-bottle” adhesive.Materials and Methods: Seventy-two extracted sound human molars and premolars were selected. Enamel of buccal surface was ground flat to expose dentin. The teeth were divided into 9 groups of 8 each. In control group (1 the adhesive “Excite” was used according tothe manufacturer, without any contamination. Conditioned and saliva contaminated dentin was (2 rinsed and blot dried, (3 rinsed, dried and re-etched. In groups 4, 5, 6 uncured adhesive was saliva contaminated and then: (4 only blot dried (5 rinsed, blot dried with adhesive reapplication and (6 resurfaced with bur, rinsed, dried and followed by repeating the whole process. In groups 7, 8, 9 cured adhesive was contaminated with saliva and then:(7 rinsed and dried (8 rinsed, blot dried with adhesive reapplication (9 same as group (6.Then “Tetric Ceram” composite cylinders were bonded to dentin surfaces. Samples were thermo cycled in 5°C and 55°C water, 30 seconds in each bath with a dowel time of 10

  16. Push-out bond strength and SEM evaluation of a new bonding approach into the root canal

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Carvalho

    2012-12-01

    Full Text Available OBJECTIVE: This study evaluated the performance of different adhesive systems in fiber post placement aiming to clarify the influence of different hydrophobic experimental blend adhesives, and of one commercially available adhesive on the frictional retention during a luting procedure. MATERIAL AND METHODS: One luting agent (70 Wt% BisGMA, 28.5% TEGDMA; 1.5% p-tolyldiethanolamine to cement fiber posts into root canals was applied with 4 different adhesive combinations: Group 1: The etched roots were rinsed with water for 30 s to remove the phosphoric acid, then rinsed with 99.6% ethanol for 30 s, and blotdried. A trial adhesive (base to catalyst on a 1:1 ratio was used with an experimental luting agent (35% Bis-GMA, 14.37% TeGDMA, 0.5% eDMAB, 0.13% CQ; Group 2: A trial adhesive (base to catalyst on a 1:2 ratio was luted as in Group 1; Group 3: One-Step Plus (OSP, Bisco Inc. following the ethanol bonding technique in combination with the luting agent as in Group 1; Group 4: OSP strictly following the manufacturer's instructions using the luting agent as in Group 1. The groups were challenged with push-out tests. Posted root slices were loaded until post segment extrusion in the apical-coronal direction. Failure modes were analyzed under scanning electron microscopy. RESULTS: Push-out strength was not significantly influenced by the luting agent (p>0.05. No statistically significant differences among the tested groups were found as Group 1 (exp 1 - ethanol-wet bonding technique=Group 2 (exp 2 - ethanol-wet bonding technique=Group 3 (OSP - ethanol-wet bonding technique=Group 4 (control, OSP - water-wet bonding technique (p>0.05. The dominating failure modes in all the groups were cohesive/adhesive failures, which were predominantly observed on the post/luting agent interface. CONCLUSIONS: The results of this study support the hypothesis that the proposal to replace water with ethanol to bond fiber posts to the root canal using highly hydrophobic

  17. Design and In-Situ Processing of Metal-Ceramic and Ceramic-Ceramic Microstructures

    National Research Council Canada - National Science Library

    Sass, Stephen

    1997-01-01

    .... Metal-ceramic microstructures have been synthesized in situ by a variety of novel processing techniques, including the partial reduction of oxide compounds and displacement reactions and sol-gel...

  18. The dynamic properties of sandwich structures based on metal-ceramic foams.

    Science.gov (United States)

    2014-01-01

    The present research program has studied the fracture properties of closed pore metal-ceramic foams for their potential applications as core systems in sandwich structures. The composite foams were created at Fireline, Inc. (Youngstown, OH) using the...

  19. Microshear bond strength of a flowable resin to enamel according to the different adhesive systems

    Directory of Open Access Journals (Sweden)

    Jeong-Ho Kim

    2011-01-01

    Full Text Available Objectives The purpose of this study was to compare the microshear bond strength (uSBS of two total-etch and four self-etch adhesive systems and a flowable resin to enamel. Materials and Methods Enamels of sixty human molars were used. They were divided into one of six equal groups (n = 10 by adhesives used; OS group (One-Step Plus, SB group (Single Bond, CE group (Clearfil SE Bond, TY group (Tyrian SPE/One-Step Plus, AP group (Adper Prompt L-Pop and GB group (G-Bond. After enamel surfaces were treated with six adhesive systems, a flowable composite resin (Filek Z 350 was bonded to enamel surface using Tygon tubes. the bonded specimens were subjected to uSBS testing and the failure modes of each group were observed under FE-SEM. Results 1. The uSBS of SB group was statistically higher than that of all other groups, and the uSBS of OS, SE and AP group was statistically higher than that of TY and GB group (p < 0.05. 2. The uSBS for TY group was statistically higher than that for GB group (p < 0.05. 3. Adhesive failures in TY and GB group and mixed failures in SB group and SE group were often analysed. One cohesive failure was observed in OS, SB, SE and AP group, respectively. Conclusions Although adhesives using the same step were applied the enamel sur

  20. Retention of metal-ceramic crowns with contemporary dental cements.

    Science.gov (United States)

    Johnson, Glen H; Lepe, Xavier; Zhang, Hai; Wataha, John C

    2009-09-01

    New types of crown and bridge cement are in use by practitioners, and independent studies are needed to assess their effectiveness. The authors conducted a study in three parts (study A, study B, and study C) and to determine how well these new cements retain metal-ceramic crowns. The authors prepared teeth with a 20-degree taper and a 4-millimeter length. They cast high-noble metal-ceramic copings, then fitted and cemented them with a force of 196 newtons. The types of cements they used were zinc phosphate, resin-modified glass ionomer, conventional resin and self-adhesive modified resin. They thermally cycled the cemented copings, then removed them. They recorded the removal force and calculated the stress of dislodgment by using the surface area of each preparation. They used a single-factor analysis of variance to analyze the data (alpha = .05). The mean stresses necessary to remove crowns, in megapascals, were 8.0 for RelyX Luting (3M ESPE, St. Paul, Minn.), 7.3 for RelyX Unicem (3M ESPE), 5.7 for Panavia F (Kuraray America, New York) and 4.0 for Fuji Plus (GC America, Alsip, Ill.) in study A; 8.1 for RelyX Luting, 2.6 for RelyX Luting Plus (3M ESPE) and 2.8 for Fuji CEM (GC America) in study B; and 4.9 for Maxcem (Kerr, Orange, Calif.), 4.0 for BisCem (Bisco, Schaumburg, Ill.), 3.7 for RelyX Unicem Clicker (3M ESPE), 2.9 for iCEM (Heraeus Kulzer, Armonk, N.Y.) and 2.3 for Fleck's Zinc Cement (Keystone Industries, Cherry Hill, N.J.) in study C. Powder-liquid versions of new cements were significantly more retentive than were paste-paste versions of the same cements. The mean value of crown removal stress for the new self-adhesive modified-resin cements varied appreciably among the four cements tested. All cements retained castings as well as or better than did zinc phosphate cement. Powder-liquid versions of cements, although less convenient to mix, may be a better clinical choice when crown retention is an issue. All cements tested will retain castings

  1. Experimental analysis of the strength of silver-alumina junction elaborated at solid state bonding

    International Nuclear Information System (INIS)

    Serier, B.; Bachir Bouiadjra, B.; Belhouari, M.; Treheux, D.

    2011-01-01

    Highlights: → The adhesion strength is closely related to the plastic deformation of the metal joint. → It is possible to transform a system with weak energy of adhesion into a system with strong energy. → The adhesion strength depends on Silver diffusion in the ceramic grains boundaries. -- Abstract: The mechanisms of ceramics-metal assemblies, particularly silver and alumina, can be better understood by studying the strength of their adhesion. These two materials are a priori non-reactive, their thermodynamic work of adhesion is low and the difference between their thermal coefficients of expansion in very considerable. In this study, the strength of silver-alumina junctions elaborated at solid state by thermo-compression is tested by an indirect tensile test and shearing one. The effects of several parameters such as: the pressure of bonding, the time of bonding, the temperature, and the oxygen dissolve in metal solid solution on the strength of the junction are analyzed. The obtained results show that the resistance of the junction is affected by all this parameters and it is essential to optimize these different parameters in order to increase the durability of the junction. It was also shown that the diffusion of the silver in alumina could be the cause of the damage of alumina near the interface.

  2. Friction stir weld assisted diffusion bonding of 5754 aluminum alloy to coated high strength steels

    International Nuclear Information System (INIS)

    Haghshenas, M.; Abdel-Gwad, A.; Omran, A.M.; Gökçe, B.; Sahraeinejad, S.; Gerlich, A.P.

    2014-01-01

    Highlights: • Successful lap joints of Al 5754 sheet to coated DP600 and 22MnB5 steels. • Negligible effect of welding speed on mechanical properties of Al 5754/22MnB5 joints. • Lower strength of Al 5754/22MnB5 joints compared with Al 5754/DP600 joints. - Abstract: In the present paper friction stir-induced diffusion bonding is used for joining sheets of 5754 aluminum alloy to coated high strength steels (DP600 and 22MnB5) by promoting diffusion bonding in an overlap configuration. Mechanical performance and microstructures of joints were analyzed by overlap shear testing, metallography, and X-ray diffraction. Our results show that the strength of joint is dependent upon tool travel speed and the depth of the tool pin relative to the steel surface. The thickness and types of intermetallic compounds formed at the interface play a significant role in achieving a joint with optimum performance. That is, the formation of high aluminum composition intermetallic compounds (i.e. Al 5 Fe 2 ) at the interface of the friction stir lap joint appeared to have a more negative effect on joint strength compared to the presence of high iron composition intermetallic phases (i.e. FeAl). This is in agreement with previously reported findings that FeAl intermetallic can improve the fracture toughness and interface strength in Al/St joints

  3. Bonding Properties of Basalt Fiber and Strength Reduction According to Fiber Orientation

    Directory of Open Access Journals (Sweden)

    Jeong-Il Choi

    2015-09-01

    Full Text Available The basalt fiber is a promising reinforcing fiber because it has a relatively higher tensile strength and a density similar to that of a concrete matrix as well as no corrosion possibility. This study investigated experimentally the bonding properties of basalt fiber with cementitious material as well as the effect of fiber orientation on the tensile strength of basalt fiber for evaluating basalt fiber’s suitability as a reinforcing fiber. Single fiber pullout tests were performed and then the tensile strength of fiber was measured according to fiber orientation. The test results showed that basalt fiber has a strong chemical bond with the cementitious matrix, 1.88 times higher than that of polyvinyl alcohol fibers with it. However, other properties of basalt fiber such as slip-hardening coefficient and strength reduction coefficient were worse than PVA and polyethylene fibers in terms of fiber bridging capacity. Theoretical fiber-bridging curves showed that the basalt fiber reinforcing system has a higher cracking strength than the PVA fiber reinforcing system, but the reinforcing system showed softening behavior after cracking.

  4. Bonding Properties of Basalt Fiber and Strength Reduction According to Fiber Orientation.

    Science.gov (United States)

    Choi, Jeong-Il; Lee, Bang Yeon

    2015-09-30

    The basalt fiber is a promising reinforcing fiber because it has a relatively higher tensile strength and a density similar to that of a concrete matrix as well as no corrosion possibility. This study investigated experimentally the bonding properties of basalt fiber with cementitious material as well as the effect of fiber orientation on the tensile strength of basalt fiber for evaluating basalt fiber's suitability as a reinforcing fiber. Single fiber pullout tests were performed and then the tensile strength of fiber was measured according to fiber orientation. The test results showed that basalt fiber has a strong chemical bond with the cementitious matrix, 1.88 times higher than that of polyvinyl alcohol fibers with it. However, other properties of basalt fiber such as slip-hardening coefficient and strength reduction coefficient were worse than PVA and polyethylene fibers in terms of fiber bridging capacity. Theoretical fiber-bridging curves showed that the basalt fiber reinforcing system has a higher cracking strength than the PVA fiber reinforcing system, but the reinforcing system showed softening behavior after cracking.

  5. Shear Bond Strength of Composite to Nd-YAG Lased Dentin with and without Dye

    Directory of Open Access Journals (Sweden)

    H. Kermanshah

    2004-06-01

    Full Text Available Statement of Problem: The achievement of a good and durable dentin/composite resin bond is an important task in restorative dentistry. The application of acid conditioners and dentin bonding agents is an accepted method to enhance this bond strength. Pretreating of dentin surface by laser irradiation seems to be a supplemental way to obtain better results,since lased dentin is more roughened and has a widest surface area to interact with acidconditioner.Purpose: In this study, the effect of dentin surface pretreating by Nd-YAG laser on dentin/composite shear bond strength was examined. Moreover, the effect of Chinese ink as a surface energy absorber on this value was investigated.Methods and Materials: Thirty-nine freshly extracted human teeth without dentinal caries were collected and their occlusal dentins were exposed using a diamond disk. The collected samples were divided into three identical groups. The dentin surface of the first group was lased by an Nd-YAG pulsed laser (100 mJ, 20 Hz through a 320 mm fiber optic in a swiping movement. In the second group, 10% solution of Chinese ink was applied on the dentinal surface before lasing. The samples of the third group were not lased at all. Thedentinal surface prepared by 35% phosphoric acid and Scotchbond MP primer and adhesive. Then, composite resin was cured on dentinal surface. After incubation, in water at 37°C for 24 hours, the samples were tested by Digital Tritest ELE machine.Results: The values of bond strength were 20.83±3.96 MPa, 17.83±3.63 MPa and 19.38±4.88 MPa for the lased, unlased and dye-enhanced groups, respectively. The results were not significant by ANOVA test (a=0.05. Although in the Weiboul modulus, the lased group offered better bond strength.Conclusion: Further studies are required to determine whether chemical as well as physical alterations to the dentin surface are induced by laser etching, and whether these influence the performance of the range of dentin

  6. Design and Characterization of High-strength Bond Coats for Improved Thermal Barrier Coating Durability

    Science.gov (United States)

    Jorgensen, David John

    High pressure turbine blades in gas turbine engines rely on thermal barrier coating (TBC) systems for protection from the harsh combustion environment. These coating systems consist of a ceramic topcoat for thermal protection, a thermally grown oxide (TGO) for oxidation passivation, and an intermetallic bond coat to provide compatibility between the substrate and ceramic over-layers while supplying aluminum to sustain Al2O 3 scale growth. As turbine engines are pushed to higher operating temperatures in pursuit of better thermal efficiency, the strength of industry-standard bond coats limits the lifetime of these coating systems. Bond coat creep deformation during thermal cycling leads to a failure mechanism termed rumpling. The interlayer thermal expansion differences, combined with TGO-imposed growth stresses, lead to the development of periodic undulations in the bond coat. The ceramic topcoat has low out-of-plane compliance and thus detaches and spalls from the substrate, resulting in a loss of thermal protection and subsequent degradation of mechanical properties. New creep resistant Ni3Al bond coats were designed with improved high-temperature strength to inhibit this type of premature failure at elevated temperatures. These coatings resist rumpling deformation while maintaining compatibility with the other layers in the system. Characterization methods are developed to quantify rumpling and assess the TGO-bond coat interface toughness of experimental systems. Cyclic oxidation experiments at 1163 °C show that the Ni3Al bond coats do not experience rumpling but have faster oxide growth rates and are quicker to spall TGO than the (Pt,Ni)Al benchmark. However, the Ni 3Al coatings outperformed the benchmark by over threefold in TBC system life due to a higher resistance to rumpling (mechanical degradation) while maintaining adequate oxidation passivation. The Ni3Al coatings eventually grow spinel NiAl2O4 on top of the protective Al2O3 layer, which leads to the

  7. Modification of Bonding Strength Test of WC HVOF Thermal Spray Coating on Rocket Nozzle

    Directory of Open Access Journals (Sweden)

    Bondan Sofyan

    2010-10-01

    Full Text Available One way to reduce structural weight of RX-100 rocket is by modifying the nozzle material and processing. Nozzle is the main target in weight reduction due to the fact that it contributes 30 % to the total weight of the structur. An alternative for this is by substitution of massive graphite, which is currently used as thermal protector in the nozzle, with thin layer of HVOF (High Velocity Oxy-Fuel thermal spray layer. This paper presents the characterization of nozzle base material as well as the modification of bonding strength test, by designing additional jig to facilitate testing processes while maintaining level of test accuracy. The results showed that the material used for  RX-100 rocket nozzle is confirmed to be S45C steel. Modification of the bonding strength test was conducted by utilizing chains, which improve test flexibility and maintains level of accuracy of the test.

  8. Microtensile Bond Strength of Polyacid-modified Composite Resin to Irradiated Primary Molars.

    Science.gov (United States)

    Keles, Sultan; Yilmaz, Yucel; Sezen, Orhan

    2018-02-01

    This study evaluated the influence of various doses of radiotherapy on the microtensile bond strength (pTBS) of compomer resin to dentin and enamel in primary molars. Thirty-five intact primary molars were collected and divided into seven groups. Teeth were irradiated with doses from 10 to 60 Gy, except for the control group. Compomer restorations were performed, and enamel-compomer resin beams and dentin-compomer resin beams were tested at a crosshead speed of 1 mm/min. No statistically significant difference was found between the irradiated tooth enamel and the control group (F = 1.1468; p = 0.194). However, statistically significant differences were evident among the dentin groups (F = 11.050; p pTBS of compomer resin to primary tooth enamel, but appears to dose dependently decrease its bond strength to primary tooth dentin. Radiotherapy may affect the success rate of compomer fillings in primary teeth, especially in deeper cavities with exposed dentin.

  9. [Effect of niobium nitride on the bonding strength of titanium porcelain by magnetron sputtering].

    Science.gov (United States)

    Wang, Shu-shu; Zhang, La-bao; Guang, Han-bing; Zhou, Shu; Zhang, Fei-min

    2010-05-01

    To investigate the effect of magnetron sputtered niobium nitride (NbN) on the bonding strength of commercially pure cast titanium (Ti) and low-fusing porcelain (Ti/Vita titankeramik system). Sixty Ti specimens were randomly divided into four groups, group T1, T2, T3 and T4. All specimens of group T1 and T2 were first treated with 120 microm blasted Al2O3 particles, and then only specimens of group T2 were treated with magnetron sputtered NbN film. All specimens of group T3 and T4 were first treated with magnetron sputtered NbN film and then only specimens of group T4 were treated with 120 microm blasted Al2O3 particles. The composition of the deposits were analyzed by X-ray diffraction (XRD). A universal testing machine was used to perform the three-point bending test to evaluate the bonding strength of Ti and porcelain. The microstructure of NbN, the interface of Ti-porcelain and the fractured Ti surface were observed with scanning electron microscopy (SEM) and energy depressive spectrum (EDS), and the results were compared. The XRD results showed that the NbN deposits were cubic crystalline phases. The bonding strength of Ti and porcelain in T1 to T4 group were (27.2+/-0.8), (43.1+/-0.6), (31.4+/-1.0) and (44.9+/-0.6) MPa. These results were analyzed by one-way analysis of variance and differences between groups were compared using least significant difference test. Significant inter-group differences were found among all groups (Pporcelain, while samples treated with both Al2O3 and NbN had better bond. EDS of Ti-porcelain interface showed oxidation occurred in T1, T2 and T3, but was well controlled in T4. Magnetron sputtered NbN can prevent Ti from being oxidized, and can improve the bonding strength of Ti/Vita titankeramik system. Al2O3 blast can also improve the bonding strength of Ti/Vita titankeramik system.

  10. Comparison of shear test methods for evaluating the bond strength of resin cement to zirconia ceramic.

    Science.gov (United States)

    Kim, Jae-Hoon; Chae, Soyeon; Lee, Yunhee; Han, Geum-Jun; Cho, Byeong-Hoon

    2014-11-01

    This study compared the sensitivity of three shear test methods for measuring the shear bond strength (SBS) of resin cement to zirconia ceramic and evaluated the effects of surface treatment methods on the bonding. Polished zirconia ceramic (Cercon base, DeguDent) discs were randomly divided into four surface treatment groups: no treatment (C), airborne-particle abrasion (A), conditioning with Alloy primer (Kuraray Medical Co.) (P) and conditioning with Alloy primer after airborne-particle abrasion (AP). The bond strengths of the resin cement (Multilink N, Ivoclar Vivadent) to the zirconia specimens of each surface treatment group were determined by three SBS test methods: the conventional SBS test with direct filling of the mold (Ø 4 mm × 3 mm) with resin cement (Method 1), the conventional SBS test with cementation of composite cylinders (Ø 4 mm × 3 mm) using resin cement (Method 2) and the microshear bond strength (μSBS) test with cementation of composite cylinders (Ø 0.8 mm × 1 mm) using resin cement (Method 3). Both the test method and the surface treatment significantly influenced the SBS values. In Method 3, as the SBS values increased, the coefficients of variation decreased and the Weibull parameters increased. The AP groups showed the highest SBS in all of the test methods. Only in Method 3 did the P group show a higher SBS than the A group. The μSBS test was more sensitive to differentiating the effects of surface treatment methods than the conventional SBS tests. Primer conditioning was a stronger contributing factor for the resin bond to zirconia ceramic than was airborne-particle abrasion.

  11. The Effect of Different Soft Drinks on the Shear Bond Strength of Orthodontic Brackets

    Directory of Open Access Journals (Sweden)

    M Omid Khoda

    2012-01-01

    Full Text Available Objective: It is proved that acidic soft drinks that are commonly used, have an adverse effect on dental structures, and may deteriorate oral heath of our patients and orthodontic appliances. The aim of this study was to compare the effect of yoghurt drink with other soft drinks on the shear bond strength of orthodontic brackets.Materials and Methods: Seventy-five first premolar teeth extracted for orthodontic purposes were selected and standard twin metal brackets were bonded on the center of buccal surface with No-Mix composite. The teeth were thermocycled for 625 cycles and randomly divided into five groups of artificial saliva, carbonated yoghurt drink with lactic acid base, non-carbonated yoghurt drink with lactic acid base, 7 up with citric acid base and Pepsi with phosphoric acid base. In all groups, the teeth were immersed in liquid for five-minute sessions three times with equal intervening intervals for 3 months. SBS was measured by a universal testing machine with a speed of 0.5mm/min. Data was analyzed statistically by one-way ANOVA.Results: The results showed that mean values for the shear bond strength of carbonated yoghurt drinks, non-carbonated yoghurt drinks, 7up and Pepsi groups were 12.98(+_2.95, 13.26(+_4.00, 16.11(+_4.89, 14.73(+_5.10, respectively. There was no statistically significant difference among the groups (P-value= 0.238Conclusion: Soft drinks used in this study did not decrease the bond strength of the brackets bonded with this specific type of composite.

  12. The effect of different soft drinks on the shear bond strength of orthodontic brackets.

    Science.gov (United States)

    Omid Khoda, M; Heravi, F; Shafaee, H; Mollahassani, H

    2012-01-01

    It is proved that acidic soft drinks that are commonly used, have an adverse effect on dental structures, and may deteriorate oral heath of our patients and orthodontic appliances. The aim of this study was to compare the effect of yoghurt drink with other soft drinks on the shear bond strength of orthodontic brackets. Seventy-five first premolar teeth extracted for orthodontic purposes were selected and standard twin metal brackets were bonded on the center of buccal surface with No-Mix composite. The teeth were thermocycled for 625 cycles and randomly divided into five groups of artificial saliva, carbonated yoghurt drink with lactic acid base, non-carbonated yoghurt drink with lactic acid base, 7 up with citric acid base and Pepsi with phosphoric acid base. In all groups, the teeth were immersed in liquid for five-minute sessions three times with equal intervening intervals for 3 months. SBS was measured by a universal testing machine with a speed of 0.5mm/min. Data was analyzed statistically by one-way ANOVA. The results showed that mean values for the shear bond strength of carbonated yoghurt drinks, non-carbonated yoghurt drinks, 7up and Pepsi groups were 12.98(±2.95), 13.26(±4.00), 16.11(±4.89), 14.73(±5.10), respectively. There was no statistically significant difference among the groups (P-value= 0.238) Soft drinks used in this study did not decrease the bond strength of the brackets bonded with this specific type of composite.

  13. Influence of saliva contamination on the shear bond strength of adhesives on enamel

    Directory of Open Access Journals (Sweden)

    Tatiana Feres Assad-Loss

    2012-04-01

    Full Text Available OBJECTIVE: To evaluate shear bond strength of 3 adhesive systems (Single Bond, TransbondTM MIP and TransbondTM XT applied on bovine enamel under saliva contamination condition. METHOD: One hundred and twenty enamel surfaces of bovine incisors were divided into 6 groups (n = 20 according to the adhesive system used (TransbondTM XT, TransbondTM MIP and Single Bond with or without saliva contamination. For each adhesive system, there were two groups defined as no contamination group (NC: 37% H3PO4 conditioning for 30 seconds and two layers of adhesive systems; saliva contamination group (SC: After the first adhesive layer application, the examined areas were contaminated with saliva. Samples were mounted appropriately for testing and stored in deionized water at 37 ºC for 7 days. Samples were then submitted to shear bond strength trials at a speed of 0.5 mm/min. The Adhesive Remnant Index (ARI was evaluated under stereomicroscopy. Two-way analysis of variance and the Tukey test were used to compare mean values (α = 0.05. RESULTS: Groups XT (NC = 26.29 ± 7.23; MIP (NC = 24.47 ± 7.52 and SB (NC = 32.36 ± 4.14 XT (SC = 19.59 ± 6.76; MIP (SC = 18.08 ± 6.39 and SB (SC = 18.18 ± 7.03 MPa. ARI 0 and 1 were the most prevalent scores in all study groups examined. CONCLUSION: Saliva contamination significantly decreased bond strength of the three adhesive systems examined (p <0.05. However, the comparison of groups with and without saliva contamination did not reveal any significant differences, and, therefore, the three systems may be considered equivalent.

  14. The Effect of Different Soft Drinks on the Shear Bond Strength of Orthodontic Brackets

    Science.gov (United States)

    Omid Khoda, M.; Heravi, F.; Shafaee, H.; Mollahassani, H.

    2012-01-01

    Objective: It is proved that acidic soft drinks that are commonly used, have an adverse effect on dental structures, and may deteriorate oral heath of our patients and orthodontic appliances. The aim of this study was to compare the effect of yoghurt drink with other soft drinks on the shear bond strength of orthodontic brackets. Materials and Methods: Seventy-five first premolar teeth extracted for orthodontic purposes were selected and standard twin metal brackets were bonded on the center of buccal surface with No-Mix composite. The teeth were thermocycled for 625 cycles and randomly divided into five groups of artificial saliva, carbonated yoghurt drink with lactic acid base, non-carbonated yoghurt drink with lactic acid base, 7 up with citric acid base and Pepsi with phosphoric acid base. In all groups, the teeth were immersed in liquid for five-minute sessions