Attractive Force in a Double-Sandwich-Type Magnetic Attachment

Dental magnetic attachments used as a retainer for overdentures are encapsulated with a corrosion resistant casing to prevent corrosion of magnets. However, some studies reported that the casing still has a risk of corrosion. This study aims to determine the effect of acid solutions on magnetic attractive force, dissolving metal ions and corrosion of magnetic attachment surfaces. The dental magnetic attachment material used is Magfit DX 600 (Aichi, Japan). It consists of assembly and keeper. The assembly and keeper immersed in acid solutions with a pH of 3.8 and 5.8 for 7 and 14 days. After immersion, the assembly and keeper were analyzed using SEM, universal testing machine, and the atomic absorption spectrophotometry to determine the surface corrosion, the magnetic attractive force, and dissolved metal ions, respectively. It is found that all assemblies showed signs of corrosion and reduction of magnetic attractive force after immersed in acid solutions with a pH of 3.8 and 5.8 for 7 and 14 days. A greater decrease in magnetic attraction was obtained at 14 days immersion in an acid solution with a pH of 3.8. Fe ion dissolution in the assembly and keeper was found to increase at 14 days of immersion. The lower the pH of the acid solution and the longer the immersion time, the signs of corrosion on the surface of dental magnetic attachment are clearly observed. The magnetic attraction force also decreased with decreasing the value of pH as well as the increase of the content of Fe ion in immersed solution.

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Size Performance of the Attractive Force for a Dental Magnetic Attachment.

Journal of the Magnetics Society of Japan ◽

10.3379/jmsjmag.20.693 ◽

1996 ◽

Vol 20 (2) ◽

pp. 693-696 ◽

Cited By ~ 3

Author(s):

Y. Honkura ◽

L. Tian ◽

A. Watarai

Keyword(s):

Attractive Force ◽

Magnetic Attachment

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Evaluation of the attractive force of different types of new-generation magnetic attachment systems

Journal of Prosthetic Dentistry ◽

10.1016/s0022-3913(11)60031-0 ◽

2011 ◽

Vol 105 (3) ◽

pp. 203-207 ◽

Cited By ~ 9

Author(s):

Hakan Akin ◽

M. Emre Coskun ◽

E. Gulsah Akin ◽

A. Kemal Ozdemir

Keyword(s):

Attractive Force ◽

Different Types ◽

Magnetic Attachment ◽

New Generation

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A Monoclonal Antibody-Based Enzyme Immunoassay for Fibrin Degradation Products in Plasma

Thrombosis and Haemostasis ◽

10.1055/s-0038-1642777 ◽

1988 ◽

Vol 59 (02) ◽

pp. 310-315 ◽

Cited By ~ 64

Author(s):

P W Koppert ◽

E Hoegee-de Nobel ◽

W Nieuwenhuizen

Keyword(s):

Enzyme Immunoassay ◽

Degradation Products ◽

Blood Clot ◽

Tissue Type ◽

Fibrin Degradation Products ◽

Type Plasminogen Activator ◽

Strong Positive Reaction ◽

Sandwich Type ◽

Capture Antibody

SummaryWe have developed a sandwich-type enzyme immunoassay (EIA) for the quantitation of fibrin degradation products (FbDP) in plasma with a time-to-result of only 45 minutes.* The assay is based on the combination of the specificities of two monoclonal antibodies (FDP-14 and DD-13), developed in our institute. FDP-14, the capture antibody, binds both fibrinogen degradation products (FbgDP) and FbDP, but does not react with the parent fibrin(ogen) molecules. It has its epitope in the E-domain of the fibrinogen molecule on the Bβ-chain between amino acids 54-118. Antibody DD-13 was raised using D-dimer as antigen and is used as a tagging antibody, conjugated with horse-radish peroxidase. A strong positive reaction is obtained with a whole blood clot lysate (lysis induced by tissue-type plasminogen activator) which is used as a standard. The EIA does virtually not detect FbgDP i. e. purified fragments X, Y, or FbgDP generated in vitro in plasma by streptokinase treatment. This indicates that the assay is specific for fibrin degradation products.We have successfully applied this assay to the plasma of patients with a variety of diseased states. In combination with the assay previously developed by us for FbgDP and for the total amount of FbgDP + FbDP (TDP) in plasma, we are now able to study the composition of TDP in patients plasma in terms of FbgDP and FbDP.

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Spectrum of Defect States in Porous Organic Low-k Dielectric Films, Annealed in Argon and Nitrogen

MRS Proceedings ◽

10.1557/proc-766-e8.5 ◽

2003 ◽

Vol 766 ◽

Author(s):

V. Ligatchev ◽

T.K.S. Wong ◽

T.K. Goh ◽

Rusli Suzhu Yu

Keyword(s):

Deep Level ◽

Dielectric Films ◽

Silicon Substrates ◽

Reverse Bias Voltage ◽

Defect States ◽

Single Side ◽

Sandwich Type ◽

Transient Spectroscopy ◽

P Type ◽

Spectrum Deconvolution

AbstractDefect spectrum N(E) of porous organic dielectric (POD) films is studied with capacitance deep-level-transient-spectroscopy (C-DLTS) in the energy range up to 0.7 eV below conduction band bottom Ec. The POD films were prepared by spin coating onto 200mm p-type (1 – 10 Δcm) single-side polished silicon substrates followed by baking at 325°C on a hot plate and curing at 425°C in furnace. The film thickness is in the 5000 – 6000 Å range. The ‘sandwich’ -type NiCr/POD/p-Si/NiCr test structures showed both rectifying DC current-voltage characteristics and linear 1/C2 vs. DC reverse bias voltage. These confirm the applicability of the C-DLTS technique for defect spectrum deconvolution and the n-type conductivity of the studied films. Isochronal annealing (30 min in argon or 60 min in nitrogen) has been performed over the temperature range 300°C - 650°C. The N(E) distribution is only slightly affected by annealing in argon. However, the distribution depends strongly on the annealing temperature in nitrogen ambient. A strong N(E) peak at Ec – E = 0.55 – 0.60 eV is detected in all samples annealed in argon but this peak is practically absent in samples annealed in nitrogen at Ta < 480°C. On the other hand, two new peaks at Ec – E = 0.12 and 0.20 eV appear in the N(E) spectrum of the samples annealed in nitrogen at Ta = 650°C. The different features of the defect spectrum are attributed to different interactions of argon and nitrogen with dangling carbon bonds on the intra-pore surfaces.

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