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Christoph H F Hammerle - One of the best experts on this subject based on the ideXlab platform.

  • the improvement of Adhesive properties of peek through different pre treatments
    Applied Surface Science, 2012
    Co-Authors: Lubica Hallmann, Albert Mehl, Nuno Sereno, Christoph H F Hammerle
    Abstract:

    Abstract The purpose of this in vitro study was the evaluation of the bond strength of the Adhesives/composite resin to Poly Ether Ether Ketone (PEEK) based dental polymer after using different surface conditioning methods. PEEK blanks were cut into discs. All disc specimens were polished with 800 grit SiC paper and divided into 6 main groups. Main groups were divided into 2 subgroups. The main groups of 32 specimens each were treated as follow: (1) control specimens (no treatment), (2) piranha solution etching, (3) abraded with 50 μm alumina particles and chemical etching, (4) abraded with 110 μm alumina particles and chemical etching, (5) abraded with 30 μm silica-coated alumina particles and chemical etching, (6) abraded with 110 μm silica-coated alumina particles and chemical etching. Plexiglas tubes filled with a composite resin (RelyX Unicem) were bonded to the specimens. The Adhesives used were Heliobond and Clearfil Ceramic Primer. Each specimen was stored in distilled water (37 °C) for 3 days. Tensile bond strength was measured in a universal testing machine and failure methods were evaluated. Abraded surface with 50 μm alumina particles followed by etching with piranha solution lead to the highest bond strength of 21.4 MPa when Heliobond like Adhesive was used. Tribochemical silica coated/etched PEEK surfaces did not have an effect on the bond strength. Non-treated PEEK surface was not able to establish a bond with composite resin. The proper Choice of Adhesive/composite resin system leads to a strong bond. Conclusion Airborne particle abrasion in combination with piranha solution etching improves the Adhesive properties of PEEK.

Berrin Dayangac - One of the best experts on this subject based on the ideXlab platform.

  • Effect of operator variability on microleakage with different Adhesive systems.
    European Journal of Dentistry, 2013
    Co-Authors: Emel Karaman, A. Rüya Yazici, Burak Aksoy, Erdem Karabulut, Gül Özgünaltay, Berrin Dayangac
    Abstract:

    Objective: The objective of this study was to evaluate the effect of operator variability on microleakage with different Adhesive systems. Materials and Methods: A total of 180 standardized Class V cavities were prepared on facial and lingual of 90 extracted human premolar teeth and randomly assigned to five groups according to the Adhesive systems used ( n = 36): Prime and Bond NT (PB), Single Bond (SB), Futura Bond NR, Xeno III (XE) and Adper Prompt-L-Pop (LP). The Adhesive groups were then further subdivided into three operator groups according to level of clinical experience ( n = 12): An undergraduate student, a research assistant and a faculty member. All cavities were restored with same composite resin. The restored teeth were thermocycled (500 cycles, 5-55°C) then immersed in 0.5% basic fuchsin and measured for leakage under a stereomicroscope. Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney U tests. Results: Significant inter-operator variation was found in the enamel margins in the XE group with significantly higher microleakage when used by the undergraduate student ( P P > 0.05), significant differences were observed between PB and LP, PB and XE, SB and LP and SB and XE in the enamel margins for the undergraduate student ( P Conclusion: Microleakage of Adhesive systems is more dependent on interactions between the operator and Adhesive material than on the Choice of Adhesive material.

  • Effect of operator variability on microleakage with different Adhesive systems.
    European journal of dentistry, 2013
    Co-Authors: Emel Karaman, A. Rüya Yazici, Burak Aksoy, Erdem Karabulut, Gül Özgünaltay, Berrin Dayangac
    Abstract:

    The objective of this study was to evaluate the effect of operator variability on microleakage with different Adhesive systems. A total of 180 standardized Class V cavities were prepared on facial and lingual of 90 extracted human premolar teeth and randomly assigned to five groups according to the Adhesive systems used (n = 36): Prime and Bond NT (PB), Single Bond (SB), Futura Bond NR, Xeno III (XE) and Adper Prompt-L-Pop (LP). The Adhesive groups were then further subdivided into three operator groups according to level of clinical experience (n = 12): An undergraduate student, a research assistant and a faculty member. All cavities were restored with same composite resin. The restored teeth were thermocycled (500 cycles, 5-55°C) then immersed in 0.5% basic fuchsin and measured for leakage under a stereomicroscope. Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney U tests. Significant inter-operator variation was found in the enamel margins in the XE group with significantly higher microleakage when used by the undergraduate student (P < 0.05). Although no significant differences in microleakage were found between Adhesive systems for the research assistant and faculty member (P > 0.05), significant differences were observed between PB and LP, PB and XE, SB and LP and SB and XE in the enamel margins for the undergraduate student (P < 0.05). Microleakage of Adhesive systems is more dependent on interactions between the operator and Adhesive material than on the Choice of Adhesive material.

  • Effect of operator variability on microleakage with different Adhesive systems
    European Journal of Dentistry, 2013
    Co-Authors: Emel Karaman, A. Rüya Yazici, Burak Aksoy, Erdem Karabulut, Gül Özgünaltay, Berrin Dayangac
    Abstract:

    ABSTRACTObjective: The objective of this study was to evaluate the effect of operator variability on microleakage with different Adhesive systems. Materials and Methods: A total of 180 standardized Class V cavities were prepared on facial and lingual of 90 extracted human premolar teeth and randomly assigned to five groups according to the Adhesive systems used (n = 36): Prime and Bond NT (PB), Single Bond (SB), Futura Bond NR, Xeno III (XE) and Adper Prompt-L-Pop (LP). The Adhesive groups were then further subdivided into three operator groups according to level of clinical experience (n = 12): An undergraduate student, a research assistant and a faculty member. All cavities were restored with same composite resin. The restored teeth were thermocycled (500 cycles, 5-55°C) then immersed in 0.5% basic fuchsin and measured for leakage under a stereomicroscope. Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney U tests. Results: Significant inter-operator variation was found in the enamel margins in the XE group with significantly higher microleakage when used by the undergraduate student (p < 0.05). Although no significant differences in microleakage were found between Adhesive systems for the research assistant and faculty member (p > 0.05), significant differences were observed between PB and LP, PB and XE, SB and LP and SB and XE in the enamel margins for the undergraduate student (p < 0.05). Conclusions: Microleakage of Adhesive systems is more dependent on interactions between the operator and Adhesive material than on the Choice of Adhesive material.

Morin-bernard Alexandre - One of the best experts on this subject based on the ideXlab platform.

  • Use of northern hardwoods in glued-laminated timber: A study of bondline shear strength and resistance to moisture
    2019
    Co-Authors: Achim Alexis, Blanchet Pierre, Dagenais Christian, Morin-bernard Alexandre
    Abstract:

    The growing demand for engineered wood products in the construction sector has resulted in the diversification of the product offer. Used marginally in structural products in North America, northern hardwoods are now attracting a growing interest from industry and policy makers because of their outstanding strength as well as their high availability and distinctive appearance. Currently, there is no standard in Canada governing the use of hardwoods in the manufacturing of glued-laminated timber. As part of a larger project aiming to assemble the basic knowledge that would lead to such standard, the specific objective of this study was to assess the shear strength in dry and wet conditions of assemblies made from different hardwood species and structural Adhesives. Results suggest that a mean shear strength as high as 20.5 MPa for white oak, 18.8 MPa for white ash and respectively 18.2 MPa and 17.4 MPa for yellow birch and paper birch can be obtained in dry conditions. The Choice of Adhesive did not affect the dry shear strength of our specimens, but differences were observed in wet conditions. Specimens bonded with melamine-formaldehyde Adhesive had generally the highest wet shear strength and wood failure values. Our results also highlight the important influence of wood density on the percentage of failure that occurs in wood and, to a lesser extent, on shear strength. Further investigations on finger joint strength and full-size bending tests will allow confirming the potential for the investigated species to be used in glued-laminated timber

Alexis Achim - One of the best experts on this subject based on the ideXlab platform.

  • Use of northern hardwoods in glued-laminated timber: a study of bondline shear strength and resistance to moisture
    European Journal of Wood and Wood Products, 2020
    Co-Authors: Alexandre Morin-bernard, Pierre Blanchet, Christian Dagenais, Alexis Achim
    Abstract:

    The growing demand for engineered wood products in the construction sector has resulted in the diversification of the product offer. Used marginally in structural products in North America, northern hardwoods are now attracting a growing interest from industry and policy makers because of their outstanding strength as well as their high availability and distinctive appearance. Currently, there is no standard in Canada governing the use of hardwoods in the manufacturing of glued-laminated timber. As part of a larger project aiming to assemble the basic knowledge that would lead to such standard, the specific objective of this study was to assess the shear strength in dry and wet conditions of assemblies made from different hardwood species and structural Adhesives. Results suggest that a mean shear strength as high as 20.5 MPa for white oak, 18.8 MPa for white ash and respectively 18.2 MPa and 17.4 MPa for yellow birch and paper birch can be obtained in dry conditions. The Choice of Adhesive did not affect the dry shear strength of these specimens, but differences were observed in wet conditions. Specimens bonded with melamine-formaldehyde Adhesive had generally the highest wet shear strength and wood failure values. These results also highlight the important influence of wood density on the percentage of failure that occurs in wood and, to a lesser extent, on shear strength. Further investigations on finger joint strength and full-size bending tests will allow confirming the potential for the investigated species to be used in glued-laminated timber.

Guangwei Meng - One of the best experts on this subject based on the ideXlab platform.

  • finite element analysis of multi piece post crown restoration using different types of Adhesives
    International Journal of Oral Science, 2013
    Co-Authors: Linwei Lu, Guangwei Meng
    Abstract:

    When restoring a missing tooth by affixing a post-and-crown to a root canal, the root canal’s strength determines the best Choice of Adhesive, researchers in China report. Zhi-Hui Liu and colleagues at Jilin University modeled the behavior of five different Adhesives — zinc phosphate, carboxylic acid zinc, glass ionomer, panavia F, and superbond — under biting and chewing stresses. Using a mathematical technique known as finite element analysis, the researchers determined that elastic Adhesives buffer the root canal against biting and chewing. Over time, however, these Adhesives show greater deformation over time, ultimately placing stress on the root canal orifice. Stiffer Adhesives transfer most of the load to the root canal, protecting the root canal orifice. Liu thus recommends elastic Adhesives for patients with thin root canals, and stiffer Adhesives for patients with thicker root canals.