Ceramic surface polariton sensor

Orthodontists must sometimes bond attachments to ceramic crowns, by using one of the surface preparations available, such as sandblasting or acid etching with hydrofluoric acid. Research shows that different laser systems may also be used for this purpose. The aim of this review is to determine which laser type and modality of use is the most effective in increasing shear bond strength of brackets bonded to ceramic surfaces. Two independent researchers studied the current literature 1990–2018 and selected original articles focusing on in vitro research on laser use for ceramic surface preparation for bonding metallic or ceramic attachments. Twelve articles have met the criteria and have been thoroughly revised, focusing on 2 fractional, Nd:Yag, Er:Yag, femtosecond and Ti:Sapphire lasers. There is little difference shown by the current studies between ceramic types and information on orthodontic bonding to non-feldspathic ceramics is scarce. Femtosecond laser is a good alternative to classical surface preparation with hydrofluoric acid. Nd:Yag laser is more suitable for surface preparation of ceramics than different types of Er:Yag lasers. Difference in laser power may achieve different results, but the golden standard for lasers use has not been found. Laser usage does not obtain the same results as hydrofluoric acid and cannot, so far, eliminate its application.

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Plasma Polymerized Allylamine—The Unique Cell-Attractive Nanolayer for Dental Implant Materials

Polymers ◽

10.3390/polym11061004 ◽

2019 ◽

Vol 11 (6) ◽

pp. 1004 ◽

Cited By ~ 4

Author(s):

J. Barbara Nebe ◽

Henrike Rebl ◽

Michael Schlosser ◽

Susanne Staehlke ◽

Martina Gruening ◽

...

Keyword(s):

Intracellular Signaling ◽

Microwave Plasma ◽

Cell Attachment ◽

Tetragonal Zirconia ◽

Surrounding Tissue ◽

Material Surface ◽

Cell Physiology ◽

Ceramic Surface ◽

Plasma Chemical ◽

Unique Cell

Biomaterials should be bioactive in stimulating the surrounding tissue to accelerate the ingrowth of permanent implants. Chemical and topographical features of the biomaterial surface affect cell physiology at the interface. A frequently asked question is whether the chemistry or the topography dominates the cell-material interaction. Recently, we demonstrated that a plasma-chemical modification using allylamine as a precursor was able to boost not only cell attachment and cell migration, but also intracellular signaling in vital cells. This microwave plasma process generated a homogenous nanolayer with randomly distributed, positively charged amino groups. In contrast, the surface of the human osteoblast is negatively charged at −15 mV due to its hyaluronan coat. As a consequence, we assumed that positive charges at the material surface—provoking electrostatic interaction forces—are attractive for the first cell encounter. This plasma-chemical nanocoating can be used for several biomaterials in orthopedic and dental implantology like titanium, titanium alloys, calcium phosphate scaffolds, and polylactide fiber meshes produced by electrospinning. In this regard, we wanted to ascertain whether plasma polymerized allylamine (PPAAm) is also suitable for increasing the attractiveness of a ceramic surface for dental implants using Yttria-stabilized tetragonal zirconia.

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The Effect of Laser Treatment on Bonding Between Zirconia Ceramic Surface and Resin Cement

Acta Odontologica Scandinavica ◽

10.3109/00016357.2010.514720 ◽

2010 ◽

Vol 68 (6) ◽

pp. 354-359 ◽

Cited By ~ 51

Author(s):

Çağri Ural ◽

Tolga Külünk ◽

Şafak Külünk ◽

Murat Kurt

Keyword(s):

Laser Treatment ◽

Resin Cement ◽

Zirconia Ceramic ◽

Ceramic Surface

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Wall Temperature Measurements in Gas Turbine Combustors With Thermographic Phosphors

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4040716 ◽

2018 ◽

Vol 141 (4) ◽

Cited By ~ 5

Author(s):

Patrick Nau ◽

Zhiyao Yin ◽

Oliver Lammel ◽

Wolfgang Meier

Keyword(s):

Gas Turbine ◽

Wall Temperature ◽

Gas Turbines ◽

High Speed ◽

Bluff Body ◽

Temperature Measurements ◽

Transient Temperature ◽

High Time Resolution ◽

Ceramic Surface ◽

Precessing Vortex Core

Phosphor thermometry has been developed for wall temperature measurements in gas turbines and gas turbine model combustors. An array of phosphors has been examined in detail for spatially and temporally resolved surface temperature measurements. Two examples are provided, one at high pressure (8 bar) and high temperature and one at atmospheric pressure with high time resolution. To study the feasibility of this technique for full-scale gas turbine applications, a high momentum confined jet combustor at 8 bar was used. Successful measurements up to 1700 K on a ceramic surface are shown with good accuracy. In the same combustor, temperatures on the combustor quartz walls were measured, which can be used as boundary conditions for numerical simulations. An atmospheric swirl-stabilized flame was used to study transient temperature changes on the bluff body. For this purpose, a high-speed setup (1 kHz) was used to measure the wall temperatures at an operating condition where the flame switches between being attached (M-flame) and being lifted (V-flame) (bistable). The influence of a precessing vortex core (PVC) present during M-flame periods is identified on the bluff body tip, but not at positions further inside the nozzle.

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Four chemical methods of porcelain conditioning and their influence over bond strength and surface integrity

Dental Press Journal of Orthodontics ◽

10.1590/2176-9451.20.4.051-056.oar ◽

2015 ◽

Vol 20 (4) ◽

pp. 51-56 ◽

Cited By ~ 5

Author(s):

João Paulo Fragomeni Stella ◽

Andrea Becker Oliveira ◽

Lincoln Issamu Nojima ◽

Mariana Marquezan

Keyword(s):

Phosphoric Acid ◽

Bond Strength ◽

Surface Integrity ◽

Hydrofluoric Acid ◽

Shear Bond Strength ◽

Testing Machine ◽

Acid Etching ◽

Ceramic Surface ◽

Surface Conditioning ◽

Phosphoric Acid Etching

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.

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