Wire Type Research Articles

Effectiveness of methods for cleaning arch wire: an in vitro study

The aim of this study was to evaluate various methods of removing bacterial and fungus biofilm, to simulate orthodontic arch wires cleaning before reinsertion in the patients appliance. Rectangular Nickel Titanium (NiTi), Stainless Steel (SS) and Titanium Molybdenum (TMA) wires were divided into five groups, then contaminated with strains of Streptococcus mutans and Candida albicas. Four segments of each group served as control and were not contaminated. Six cleanings methods were used to remove the biofilm: cotton roll and a chemical agent (chlorhexidine, sodium hypochlorite, 70% alcohol), cotton roll and water, steel woll and immersion on enzymatic detergent. There was a control group not decontaminated Then wires were placed in broth separately, and after an incubation period the optical density (OD) was measured, observing whether there was microbial growth. A wire segment of each subgroup of SS 3M® was taken to the Scanning Electron Microscope (SEM) for visualization of the treatment response. The results were submitted to one-way ANOVA test and Tukey post-test. With the exception of 70% alcohol, the disinfection means behaved similarly regardless the type of wire. Two percent Chlorhexidine and 1% Sodium Hypochlorite totally removed the microorganisms while other agents left a high microbial concentration. Chemical cleaning is necessary to remove biofilm in orthodontic wires; 1% Sodium Hypochlorite and 2% Chlorhexidine are good disinfectants for this purpose.

Comparative Numerical Analysis between Two Types of Orthodontic Wire for the Lingual Technique, Using the Finite Element Method.

In the lingual orthodontic technique, there are two paradigms regarding the type of wire used. Regardless of the material or gauge, some orthodontists choose to use the straight wire and resin and bond it to the surface of the tooth; they call it compensations. Other orthodontists prefer to bend the wire, giving it a mushroom shape. There is no specific indication for the use of each type of wire, so orthodontists use them according to their criteria. The present study establishes the bases so that it is possible to find the indications for each type of wire. A clinical trial of a lingual orthodontic patient was used. To carry out the comparative study, a straight arch was placed in his right arch and a mushroom arch in the left arch. Using 3D imaging, a high-biofidelity biomodel of the patient's mandible was generated, with which the FEM analysis was performed, which allowed comparing the reactions of the mandibular bone and appliances with the different arches. It was found that, on the side with the straight arch, there were greater deformations, and in the mushroom arch, there were greater stresses. With this, it is possible to find which clinical cases in each type of wire are indicated.

Functional connectivity and upper limb function in patients after pediatric arterial ischemic stroke with contralateral corticospinal tract wiring

To develop individualized motor rehabilitation, knowledge of the relationship between neuroplastic reorganization and motor recovery after pediatric arterial ischemic stroke (AIS) is crucial. Thus, we investigated functional connectivity in patients after AIS with good motor outcome and in patients with hemiparesis compared with typically developing peers. We included 18 patients (n = 9 with hemiparesis, n = 9 with good motor outcome) with pediatric AIS in the chronic phase (≥ 2 years after diagnosis, diagnosed > 16 years) and 18 peers matched by age and gender. Participants underwent a standardized motor assessment, single-pulse transcranial magnetic stimulation to determine the type of corticospinal tract wiring, and resting-state functional magnetic resonance imaging to examine motor network connectivity. Corticospinal tract wiring was contralateral in all participants. Patients with hemiparesis had lower interhemispheric connectivity strength compared with patients with good clinical outcome and peers. Patients with good clinical outcome had higher intrahemispheric connectivity strength compared with peers. Further, higher intrahemispheric connectivity was related to better motor outcome in patients. Our findings suggest that better motor outcome after pediatric AIS is related to higher motor network connectivity strength. Thus, resting-state functional connectivity might be predictive for motor recovery after pediatric AIS.

Preparation and evaluation of polyester-cotton/wire blended conductive woven fabrics for electromagnetic shielding

For the pursuit of conductive textiles with high electromagnetic shielding performance, specified yarns are processed with a special spinning feeding device with twist counts of 40 T, 50 T, 60 T, 70 T, 80 T, and 90 T, for Next, the optimal yarns from each group are made into SS/Pc-70 and Cu/Pc-80 conductive woven fabrics with a plain weave structure design. In addition, the surface resistivity, electromagnetic shielding effectiveness measurement and air permeability of the two conductive woven fabrics were tested and analyzed. Regarding the electromagnetic shielding performance test, the effects of the complete shielding network, the lamination layers of fabric, and lamination angle on the electromagnetic shielding performance are discussed. The test results indicate that Cu/Pc-80 woven fabrics has the lowest surface resistivity, which means it has the best electrical conductivity; Moreover, different types of metal wires provide the conductive fabrics with different levels of surface resistance. The variations in the lamination angles help attain a complete conductive network that significantly enhances the EMSE, and Cu/Pc-80 have a greater average shielding value comparatively and thus greater EMSE. For both types of conductive woven fabrics, one-layered conductive woven fabrics exhibit the maximal air permeability. As the air permeability of conductive woven fabrics is correlated with the thickness of fabrics, the greater the number of lamination layers, the lower the air permeability of the conductive fabrics.

Thermoelectric Properties of Oligoyne-Molecular Wires

Oligoynes are prototype molecular wires due to their conjugated system and the coherent tunneling transport, which aids this type of wires to transfer charges over long distances. The electric and thermoelectric characteristics for a series of Oligoyne molecular wires ((n) 3, 5, 7 and 9) are studied to explore the fundamental transport mechanisms for electrons crossing through single molecules, we probed both the electrical conductance and Seebeck coefficient for Au|molecule|Au configurations using the density functional theory (DFT). Our results not only confirmed the expected exponential decrease of conductance with the number n of triple bonds, according to the formula G n = A e −β n , but also demonstrated that the linear increase in the Seebeck coefficient S n with the number of triple bonds.

The Influence of Concrete Cover, Type of Wire Indentation and Concrete Mix on Bond between Steel and Concrete in Prismatic Prestressed Concrete Members

This research was focused on evaluating the influence of the different variables that affectsplitting in prestressed concrete members, particularly prestressed concrete ties. These include the thickness of concrete cover, release strength of concrete, and the type of wire indentation. Different combinations of these variables can affect splitting. This research was focused on finding the best possible material characteristics to avoid potential failures in the field. The objective of this research was to set the minimum value of the thickness of concrete cover, for different wire types used in manufacturing having given types of aggregate for concrete mixture. The importance of this research was to identify the best materials and the best system (concrete, wire, cover) designs before the production of prestressed concrete ties. Splitting test results presented in this research were focusedon three different thicknesses of concrete cover, three different concrete mixes, a 4500psi concrete release strength, and seven different indented wire types.

Computational Modeling of Compressive Behavior of Wire-Reinforced Bulk Metallic Glass Matrix Composites

The effect of wire type and volume fraction on the compressive behavior of wire-reinforced bulk metallic glass (BMG) matrix composites were investigated using the finite element method. The composites and test procedure were simulated in the ABAQUS software, and analyses on stress propagation and extracted compressive stress–strain curves were performed, which showed an acceptable agreement with experimental results. The results exhibited that Ta, Mo, W and Stainless Steel type 302 as the reinforcement wires significantly improved the plastic strain of the composites. Meanwhile, W wires sustained the composite strength in the same level of monolithic BMG, without sacrificing noticeable plastic strain of the composite in comparison with other reinforcements. The different volume fractions of W wires showed that the trend of plastic strain progress with increase in the second phase reaches a maximum at 65% of reinforcements. This behavior is caused by the fracture mechanism of the composites which is in its optimum condition when the reinforcement volume fraction is equal to 65%. The mechanical properties of the wire-reinforced BMG composites can be modeled by using the iso-strain Voigt model, which allows the prediction of the mechanical properties of a composite from the volume-weighted averages of the components properties. The above-mentioned findings corroborate the experiments elsewhere and may be considered as a valuable starting point to lead the future researches.

Research of micro EDM/ECM method in same electrolyte with running wire tool electrode

A micro rod machining method which can switch between electrical discharge machining (EDM) and electrochemical machining (ECM) by attaching/detaching a diode to/from a bipolar pulse generator in parallel to the working gap was newly developed using a wire electrode made of tungsten. The problem of the wire electrode wear was eliminated by the use of the wire electrochemical turning (WECT) method in which the tungsten wire electrode is continuously running. The ultra-short bipolar pulse current was generated by the electrostatic induction feeding method where a pulse voltage is coupled to the working gap through a feeding capacitance. The machining characteristics of three types of wire guide; disk-shaped WC guide, laminated wire guide and cylindrical acrylic guide, were studied. The experimental results showed that the cylindrical acrylic guide has the best machining characteristics without the influence of guide wear and with less stray current flowing through the working gap. Using the cylindrical acrylic guide, the influences of the feeding capacitance C1, and the total amplitude of the pulse voltage on the machining characteristics were studied. Finally, a stainless steel SUS 304 micro-rod with a high aspect ratio of 14 was fabricated efficiently by using the EDM and ECM modes for rough and finish machining in sequence with the same setup, pulse generator, and neutral electrolyte.

Multipoint indentation for material identification in three-dimensional observation based on serial sectioning

Three-dimensional (3D) observations of internal structures are important for evaluating material properties. Serial sectioning with destructive processes is traditionally employed as a 3D observation method. Identifying the boundaries of elements in microscope images and measuring the mechanical properties of each element are required for the evaluation of the mechanical properties of composite materials. This study provides a system for measuring the local hardness and elastic modulus by conducting indentation tests during serial sectioning processes. An automatic serial sectioning observation was performed during a combination process of precision cutting in high-speed milling with a single-crystal diamond tool and microscopic observation. A Vickers indenter was attached to a tool spindle table, and indentation tests were conducted under a displacement control process at submicron spatial resolution. The indentation modulus was obtained by analyzing the force–displacement profile measured during the unload process. The scale effects relating to the indentation depth in the measurements of the indentation modulus were confirmed for an Al alloy sample measured in this system. This study focused on the identification of components by using hardness information measured under the same indentation depth on a two-dimensional flat surface after precision cutting of the material. Three types of metal wires (1 mm diameter) embedded in plastic resin were used in the experiment. The hardness distributions on the serial sectioning surfaces were measured, and the values measured at each wire area on 3D positions were used for the identification of their material properties. This serial sectioning observation creates a 3D microstructural model including not only microscopic images, but also hardness and elastic modulus information for the identification of components in the microscopic area.

Behavior of strengthened Timber Concrete Composite under axial loads

The research study focuses on different strengthening techniques for timber concrete composites (TCC) using different types of wire and wire mesh integrated with a layer of epoxy on a timber core embedded in concrete using experimental and analytical procedure. The impact of TCC on axial compression performance, modulus of elasticity, failure mode and post failure behavior and ductility were compared to reference concrete specimens. Different types of wire and wire mesh used in strengthening of the timber core, timber core size and reinforcement in the concrete cylinder were all parameters considered in this study. Timing of application of the epoxy on the wire strengthened timber core was very important. For structural applications, where the weight reduction and ductility as well as post failure endurance are essential, the development of this composite is recommended. The ratio of the ductility index to the weight is discussed. The light weight of the timber composite, and the increased ductility were noted in this study. An equation to estimate the axial compression capacity of the strengthened timber concrete composite was developed in this study. This study will pave the way for further applications for timber concrete composite aiming at reducing dead weight of concrete and the reducing the amount of concrete and steel in construction.

The effect of fluoride gel on tensile properties, surface morphology and chemical composition of two types of orthodontic wires (an in-vitro study).

OBJECTIVE:Stainless steel and nickel-titanium wires are commonly used in fixed orthodontic appliances. Orthodontists often prescribe fluoride gel to avoid demineralization of teeth. This study investigated the effect of acidulated phosphate fluoride gel on the tensile properties, surface morphology and surface chemical composition of stainless steel and nickel-titanium wires.METHODS:Forty samples of stainless steel and nickel-titanium wires were examined, twenty for each type. Each wire type was divided into four subgroups. The first subgroup was not immersed in fluoride gel and considered as control, while the other three subgroups were immersed in 10 mL of fluoride gel for different periods of time. Then, the wires were removed from the gel, rinsed in a distilled water and left to dry. The ultimate tensile force of each wire was measured using a tensile testing machine. Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to examine the control and 24 h immersed subgroups.RESULTS:One-way analysis of variance ANOVA showed that there were no significant differences in the ultimate tensile forces between control and fluoride-treated subgroups (P = 0.172 for SS wires and P = 0.672 for NiTi wires). However, changes in the surface morphology and elemental composition of wires were shown by the SEM and EDX.CONCLUSIONS:Although immersion of stainless steel and nickel-titanium wires in the fluoride gel did not affect their tensile properties, however, surface deterioration was evident. So, further investigations are recommended to study the effect of these changes on the oral health of patients.

Innovative Alternatives for Inlay Technique in Support of Metal Work Craftsmen

Handicrafts are considered part of the history and civilization at any country, they cover a wide area of Egyptian heritage, in which the craftsman or manufacturer depends on his individual skills, using the simplest materials that used since ancient times, and by fastest methods, so it can be called heritage techniques. The heritage products are characterized by having an important role in stimulating and promoting tourism, as the heritage products are considered the most important products that tourists buy as a souvenir that refers to the country that they visited and thus have great economic importance. But, with the rapid development of manufacturing technologies and processes, the traditional crafts became neglected, so the technological development and the use of machines cause no interest in these old industries also workers (craftsmen) left them, till these crafts nearly disappeared, and the heritage products in our country are imported from abroad!! The inlay technique is considered one of the most important heritage techniques in decorating the surfaces of metal products, as the products implemented with this method are distinguished by the beauty and sustainability of their appearance achieved in contrasting color and retaining of its elegance due to the selection of high-quality materials such as gold and silver, it consists in engraving the design on the surface of the metal with undercut, then filling the excavated parts with another metal, more valuable metal, such as gold, silver or copper. More recently, designers and craftsmen have turned to the so-called (revival of the national heritage), so it is important to search for alternatives and new solutions for inlay technique, as it has a great role in reviving handicrafts and heritage products because of their great economic importance, also to encourage craftsmen to return to work and develop this technique, by finding new methods for removing and additive processes that are included in the Inlay technique, in order to be characterized by the ease of implementation. Statement of the problem: The problem of this research is how to find new alternativesfor Inlay techniques, and how to apply these alternatives on metal products, to make it easier for the craftsman to implement it. Objective: the research aims to study the productive assets of Inlay technique and how to find various technical alternatives. Significance: The importance of research is summarized in reviving the heritage techniques and the distinctive character of handicrafts in the metal product, and finding innovative alternatives for Inlay technique to make the implementation easier. Methodology: The study follows the descriptive and analytical approach. Results: 1. the possibility of making use of advanced manufacturing processes and applying them in the implementation of the inlay technique. 2. the traditional engraving methods can be replaced by electrical engraving pens for engraving and making undercut or by chemical removing layers(zincograph) to facilitate the manufacturer. 3. It is possible to fill in more than one type of metal sheet or wire in a whole product, but when using different colors of gold or different metals in the inlay start with hardest metal, which mean the hardest material is inlayed first, as silver first then do the gold24k, unlike applying two types of metallic paste, where gold 24k is added first and then silver because the firing degree of gold is higher up to 1000°C as for silver, it reaches 850°C.

An overview on types of electrical wire and ITS uses

An overview on types of electrical wire and ITS uses

Comparison of force loss during sliding of low friction and conventional TMA orthodontic archwires : An invitro study.

ObjectiveThe goal was to measure and compare the amount of force loss during tooth movement guided by archwires, including a newly introduced low-friction titanium molybdenum alloy (TMA), conventional TMA, and stainless steel archwires.MethodsThe force loss was measured using a specialized biomechanical set-up, the orthodontic measurement and simulation system (OMSS). A total of 30 specimen were used (10 low-friction TMA (TMA-Low), 10 conventional TMA (TMA-C), and 10 stainless steel (SS) archwires, each having a dimension of 0.016 × 0.022 inches). The conventional and low friction TMA archwires served as test groups, while the SS archwires served as the control group.ResultsThe mean values of force loss between the three types of wires (TMA‑C, TMA-Low, and SS) were significantly different (p < 0.0001). The highest mean force loss during sliding movement was found in the conventional TMA group (72.1%), followed by low friction TMA (48.8%) and stainless steel wires (33.7%) in a descending order.ConclusionThe friction property of the low friction TMA archwire was superior to the conventional TMA archwire but was still inferior to the stainless steel archwire.

Corrosion resistance of hoisting ropes

Abstract In this study, the goal is to determine the types of steel rope best used in environments such as harbors and on ships, by examining the behavior of different types of steel wire hoisting ropes used in cranes with respect to corrosion. Initially, hemp and steel wire core ropes were taken from 6 × 19 Standard, 8 × 19 Seale and 6 × 36 Warrington Seale rope groups that have the same diameter. Corrosion resistance was compared in these ropes through the application of three methods. According to the first method, corrosion resistance was examined via change in material mass. For this purpose, ropes were subjected to an accelerated aging test in an aging test cabin in accordance with ASTM B117 standard for one month for each aging process. 3 different 30-day processes were followed with 24-hour cycles. Corrosion exposure rates differed for each process. After going through the aging process, the damage suffered by the ropes was determined via visual inspection and the impact left by corrosion was evaluated by examining the mass changes seen in the ropes before and after aging for each process. The Tafel extrapolation, which is an electrochemical test, was applied in the second method. Ecorr and Icorr values of the ropes as well as their corrosion rates were determined and compared. Corrosion behavior was investigated in the third method through the application of mechanical experiments on aged steel ropes. In conclusion, corrosion resistant hoisting ropes were identified by comparing the results attained from the three methods.

Corrosion resistance of hoisting ropes

Abstract In this study, the goal is to determine the types of steel rope best used in environments such as harbors and on ships, by examining the behavior of different types of steel wire hoisting ropes used in cranes with respect to corrosion. Initially, hemp and steel wire core ropes were taken from 6 × 19 Standard, 8 × 19 Seale and 6 × 36 Warrington Seale rope groups that have the same diameter. Corrosion resistance was compared in these ropes through the application of three methods. According to the first method, corrosion resistance was examined via change in material mass. For this purpose, ropes were subjected to an accelerated aging test in an aging test cabin in accordance with ASTM B117 standard for one month for each aging process. 3 different 30-day processes were followed with 24-hour cycles. Corrosion exposure rates differed for each process. After going through the aging process, the damage suffered by the ropes was determined via visual inspection and the impact left by corrosion was evaluated by examining the mass changes seen in the ropes before and after aging for each process. The Tafel extrapolation, which is an electrochemical test, was applied in the second method. Ecorr and Icorr values of the ropes as well as their corrosion rates were determined and compared. Corrosion behavior was investigated in the third method through the application of mechanical experiments on aged steel ropes. In conclusion, corrosion resistant hoisting ropes were identified by comparing the results attained from the three methods.

Sensitivity and spatial resolution for thermal conductivity measurements using noncontact scanning thermal microscopy with thermoresistive probes under ambient conditions

AbstractThermoresistive probes are increasingly popular in thermal conductivity characterization using scanning thermal microscopy (SThM). A systematic analysis of the thermal conductivity measurement performance (sensitivity and spatial resolution) of thermoresistive SThM probe configurations that are available commercially is of interest to practitioners. In this work, the authors developed and validated 3D finite element models of noncontact SThM with self-heated thermoresistive probes under ambient conditions with the probe–sample heat transfer in transition heat conduction regime for the four types of SThM probe configurations resembling commercially available products: Wollaston wire (WW) type probe, Kelvin nanotechnology (KNT) type probe, doped silicon (DS) type probe and nanowire (NW) type probe. These models were then used to investigate the sensitivity and spatial resolution of the WW, KNT, DS and NW type probes for thermal conductivity measurements in noncontact mode in ambient conditions. The comparison of the SThM probes performance for measuring sample thermal conductivity and for the specific operating conditions investigated here show that the NW type probe has the best spatial resolution while the DS type probe has the best thermal conductivity measurement sensitivity in the range between 2 and 10 W·m−1·K−1. The spatial resolution is negatively affected by large probe diameters or by the presence of the cantilever in close proximity to the sample surface which strongly affects the probe–sample heat transfer in ambient conditions. An example of probe geometry configuration optimization was illustrated for the WW probe by investigating the effect of probe wire diameter on the thermal conductivity measurement sensitivity, showing ∼20% improvement in spatial resolution at the diameter with maximum thermal conductivity measurement sensitivity.

Low Temperature Metal Additive Manufacturing with the Electrochemical Process

Additive manufacturing(AM) is a manufacturing technique that produces three-dimensional objects by sequentially stacking layer of material. Due to freedom of design, it is used in various industrial applications. There are many materials capable to use in AM. Among them, polymer-based AM is the most widely used, because the polymer is easy to sinter at low temperature. However, interests in metal-based AM have been increasing due to its advantages such as mechanical strength, electric conductivity and heat dissipation. Thus, many studies of metal-based AM method have been conducted. The most commonly methods for metal AM are selective laser melting(SLM), electron beam melting(EBM), direct metal deposition(DMD), and selective laser sintering(SLS). However, these methods need a high-temperature heat source to melt material. As a result, introducing the structural anisotropy and unfavorable microstructures are inevitable. Also, local defects caused by incomplete sintering, substrate delamination, and distortion are significant problems that degrades the quality of final products[1].On the other hand, a new type of low-temperature electrochemical-based AM method has been developed. Localized electrochemical deposition(LECD) is a method utilizing electrochemical deposition on the specific area in the electrolyte. The electrochemical deposition has many advantages over other techniques because it is simple, damage-free from high temperature, and cost-effective . In LECD, instead of using conventional anode, wire type anode is used. This wire type anode with small area will produce strongly localized reduction reactions in the electrolyte. In this method, only the end of the tip of wire anode is involved in the electrochemical reaction. Theoretically, this technique can move micro anodes to produce flexible geometry features with a high aspect ratio. So far, the LECD has been used to fabricate a copper pillar, and not much research has been conducted on various structures[2-3]. Therefore, it is necessary to study the fabrication of other structures.In this research, we fabricated copper and nickel 3D structures through Electrochemical Additive Manufacturing (ECAM). We studied that morphologies of a deposited metal wall shape structures which could be obtained by controlling the applied current, temperature, and distance between cathode and anode. Additionally, the effect of organic additives on metal structure profiles was investigated. Additionally, nine(3x3) copper pin array was fabricated on the polymeric substrate, which cannot be manufactured by high-temperature laser-based metal 3D printing. Also, we confirmed that its bendability was well maintained. The micro anode used in this study was made of a Platinum wire of 100μm. This platinum wire was insulated by a capillary glass tube, then filled with epoxy resin. The surface of the anode was polished using sandpaper. The cathode was a copper wafer (1cm × 1cm × 1μm). The cathode was placed horizontally in the electrolytic cell, while anode was arranged perpendicular to the cathode. The entire experimental process was controlled by micropositioner and appropriate computer software. The changes in voltage and current during the process were monitored. The surface and microstructure were characterized by scanning electron microscopy (SEM) and optical microscope (OM). Reference [1] Y.K. Kim, D.H Kang, H.R. Kim, S.B. Kim and B.Y Yoo, “The Characteristics of Selective 3D Metal Additive Process Using Electrochemical Deposition and Nozzle Fluid Dynamics”, Frontiers in Mechanical Engineering, 6 (2020).[2] E. M. El-Giar, R. A. Said, G. E. Bridges and D. J. Thomson, “Localized Electrochemical Deposition of Copper Microstructures”, Journal of The Electrochemical Society, 147 (2000).[3] S.k. Seol, A. R. Pyun, Y. Hwu, G. Margaritondo and J.h. Je, “Localized Electrochemical Deposition of Copper Monitored Using Real-Time X-ray Microradiography”, Advanced Functional Materials, 15, 934 (2005).

Design and Performance Analysis of a Saturated Iron-Core Superconducting Fault Current Limiter for DC Power Systems

A saturated iron-core superconducting fault current limiter (SI-SFCL) can significantly limit the magnitude of the fault current and reduce the stress on circuit breakers in direct current (DC) power systems. The SI-SFCL consists of three main parts: one magnetic iron-core, one normal conductive primary coil (CPC), and one superconducting secondary coil (SSC). This paper deals with the design options for the coil system of the SI-SFCL and confirms their operating characteristics through a physical experiment. The electromagnetic characteristics and operational features of the SI-SFCL was analyzed by a 3D finite element method simulation model. The design of the SSC was based on shape, wire types, required fault current limit and protection aspects. In the CPC, the bobbin was designed based on material selection, cost, structural design, and the effects of the SI-SFCL on the fault current limit. Based on these simulation results, a laboratory-scale SI-SFCL was developed, specifically fabricated to operate on a 500 V, 50 A direct current (DC) power system. In the experiment, the operating characteristics of each coil were analyzed, and the fault current limit of the SI-SFCL according to the operating currents of the SSC and bobbin design of the CPC were confirmed. Finally, the cost analysis of the SI-SFCL with the proposed design options of the coil system was implemented. The results obtained through this study can be effectively used to large-scale SI-SFCL development studies for high-voltage direct current (HVDC) power systems.

Comparative Evaluation of Biofilm Adhesion to Different Types of Archwire and Microbiological Colonization During Orthodontic Treatment

Objective: To evaluate the biofilm adhesion to 4 types of ‘as retrieved’ archwires during orthodontic treatment. To compare biofilm formation by viable cell counting (colony-forming units [CFU]) of microbes ( Staphylococcus aureus, Streptococcus mutans and Candida albicans). Methods: The study was conducted on 40 patients who were divided into 4 equal groups based on the type of archwire of same cross-section (0.019" × 0.025"): group 1—copper-nickel titanium (Cu-NiTi); group 2—titanium molybdenum alloy (TMA); group 3—stainless steel (SS); and group 4—aesthetic coated SS. After 1 month of fixed orthodontic therapy, the archwires were removed carefully from the oral cavity. Results: Biofilm absorbance and biofilm concentration were significant ( P ≤ .05) in all the 4 groups. Conclusion: The group 2 wire showed the maximum affinity for biofilm absorbance and biofilm concentration, whereas the group 4 wire showed the least affinity. The group 4 wire promoted less retention of oral bacteria compared with the wires of the other groups, whereas the group 1 wire showed maximum retention. In the present study, all types of wire showed maximum affinity for S mutans and the least affinity for C albicans, except for the group 1 wire, which showed maximum affinity for S aureus. Biofilm adhesion could be a significant determining factor in the selection of orthodontic archwire for patients primarily at risk of dental caries or periodontal diseases, or both.