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Sample records for fully implantable 96-channel

  1. A fully implantable rodent neural stimulator

    Perry, D. W. J.; Grayden, D. B.; Shepherd, R. K.; Fallon, J. B.

    2012-02-01

    The ability to electrically stimulate neural and other excitable tissues in behaving experimental animals is invaluable for both the development of neural prostheses and basic neurological research. We developed a fully implantable neural stimulator that is able to deliver two channels of intra-cochlear electrical stimulation in the rat. It is powered via a novel omni-directional inductive link and includes an on-board microcontroller with integrated radio link, programmable current sources and switching circuitry to generate charge-balanced biphasic stimulation. We tested the implant in vivo and were able to elicit both neural and behavioural responses. The implants continued to function for up to five months in vivo. While targeted to cochlear stimulation, with appropriate electrode arrays the stimulator is well suited to stimulating other neurons within the peripheral or central nervous systems. Moreover, it includes significant on-board data acquisition and processing capabilities, which could potentially make it a useful platform for telemetry applications, where there is a need to chronically monitor physiological variables in unrestrained animals.

  2. A Fully Implantable, NFC Enabled, Continuous Interstitial Glucose Monitor

    Anabtawi, Nijad; Freeman, Sabrina; Ferzli, Rony

    2016-01-01

    This work presents an integrated system-on-chip (SoC) that forms the core of a long-term, fully implantable, battery assisted, passive continuous glucose monitor. It integrates an amperometric glucose sensor interface, a near field communication (NFC) wireless front-end and a fully digital switched mode power management unit for supply regulation and on board battery charging. It uses 13.56 MHz (ISM) band to harvest energy and backscatter data to an NFC reader. System was implemented in 14nm ...

  3. A Fully Implantable, NFC Enabled, Continuous Interstitial Glucose Monitor.

    Anabtawi, Nijad; Freeman, Sabrina; Ferzli, Rony

    2016-02-01

    This work presents an integrated system-on-chip (SoC) that forms the core of a long-term, fully implantable, battery assisted, passive continuous glucose monitor. It integrates an amperometric glucose sensor interface, a near field communication (NFC) wireless front-end and a fully digital switched mode power management unit for supply regulation and on board battery charging. It uses 13.56 MHz (ISM) band to harvest energy and backscatter data to an NFC reader. System was implemented in 14nm CMOS technology and validated with post layout simulations.

  4. Fully phase-encoded MRI near metallic implants using ultrashort echo times and broadband excitation.

    Wiens, Curtis N; Artz, Nathan S; Jang, Hyungseok; McMillan, Alan B; Koch, Kevin M; Reeder, Scott B

    2018-04-01

    To develop a fully phase-encoded MRI method for distortion-free imaging near metallic implants, in clinically feasible acquisition times. An accelerated 3D fully phase-encoded acquisition with broadband excitation and ultrashort echo times is presented, which uses a broadband radiofrequency pulse to excite the entire off-resonance induced by the metallic implant. Furthermore, fully phase-encoded imaging is used to prevent distortions caused by frequency encoding, and to obtain ultrashort echo times for rapidly decaying signal. Phantom and in vivo acquisitions were used to describe the relationship among excitation bandwidth, signal loss near metallic implants, and T 1 weighting. Shorter radiofrequency pulses captured signal closer to the implant by improving spectral coverage and allowing shorter echo times, whereas longer pulses improved T 1 weighting through larger maximum attainable flip angles. Comparisons of fully phase-encoded acquisition with broadband excitation and ultrashort echo times to T 1 -weighted multi-acquisition with variable resonance image combination selective were performed in phantoms and subjects with metallic knee and hip prostheses. These acquisitions had similar contrast and acquisition efficiency. Accelerated fully phase-encoded acquisitions with ultrashort echo times and broadband excitation can generate distortion free images near metallic implants in clinically feasible acquisition times. Magn Reson Med 79:2156-2163, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  5. 96-Channel receive-only head coil for 3 Tesla: design optimization and evaluation.

    Wiggins, Graham C; Polimeni, Jonathan R; Potthast, Andreas; Schmitt, Melanie; Alagappan, Vijay; Wald, Lawrence L

    2009-09-01

    The benefits and challenges of highly parallel array coils for head imaging were investigated through the development of a 3T receive-only phased-array head coil with 96 receive elements constructed on a close-fitting helmet-shaped former. We evaluated several designs for the coil elements and matching circuitry, with particular attention to sources of signal-to-noise ratio (SNR) loss, including various sources of coil loading and coupling between the array elements. The SNR and noise amplification (g-factor) in accelerated imaging were quantitatively evaluated in phantom and human imaging and compared to a 32-channel array built on an identical helmet-shaped former and to a larger commercial 12-channel head coil. The 96-channel coil provided substantial SNR gains in the distal cortex compared to the 12- and 32-channel coils. The central SNR for the 96-channel coil was similar to the 32-channel coil for optimum SNR combination and 20% lower for root-sum-of-squares combination. There was a significant reduction in the maximum g-factor for 96 channels compared to 32; for example, the 96-channel maximum g-factor was 65% of the 32-channel value for acceleration rate 4. The performance of the array is demonstrated in highly accelerated brain images.

  6. Implementation of a transcutaneous charger for fully implantable middle ear hearing device.

    Lim, H; Yoon, Y; Lee, C; Park, I; Song, B; Cho, J

    2005-01-01

    A transcutaneous charger for the fully implantable middle ear hearing device (F-IMEHD), which can monitor the charging level of battery, has been designed and implemented. In order to recharge the battery of F-IMEHD, the electromagnetic coupling between primary coil at outer body and secondary coil at inner body has been used. Considering the implant condition of the F-IMEHD, the primary coil and the secondary coil have been designed. Using the resonance of LC tank circuit at each coil, transmission efficiency was increased. Since the primary and the secondary coil are magnetically coupled, the current variation of the primary coil is related with the impedance of internal resonant circuit. Using the principle mentioned above, the implanted module could transmit outward the information about charging state of battery or coupling between two coils by the changing internal impedance. As in the demonstrated results of experiment, the implemented charger has supplied the sufficient operating voltage for the implanted battery within about 10 mm distance. And also, it has been confirmed that the implanted module can transmit information outward by control of internal impedance.

  7. A Fully Implantable Pacemaker for the Mouse: From Battery to Wireless Power

    Zellmer, Erik R.; Weinheimer, Carla J.; MacEwan, Matthew R.; Cui, Sophia X.; Nerbonne, Jeanne M.; Efimov, Igor R.

    2013-01-01

    Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days) pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24) were implanted with endocardial, battery-powered devices (n = 14) and epicardial, wireless-powered devices (n = 10). Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1%) mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10%) mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice. PMID:24194832

  8. A fully implantable pacemaker for the mouse: from battery to wireless power.

    Laughner, Jacob I; Marrus, Scott B; Zellmer, Erik R; Weinheimer, Carla J; MacEwan, Matthew R; Cui, Sophia X; Nerbonne, Jeanne M; Efimov, Igor R

    2013-01-01

    Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days) pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24) were implanted with endocardial, battery-powered devices (n = 14) and epicardial, wireless-powered devices (n = 10). Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1%) mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10%) mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice.

  9. A fully implantable pacemaker for the mouse: from battery to wireless power.

    Jacob I Laughner

    Full Text Available Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24 were implanted with endocardial, battery-powered devices (n = 14 and epicardial, wireless-powered devices (n = 10. Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1% mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10% mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice.

  10. Spiral-Shaped Piezoelectric MEMS Cantilever Array for Fully Implantable Hearing Systems

    Péter Udvardi

    2017-10-01

    Full Text Available Fully implantable, self-powered hearing aids with no external unit could significantly increase the life quality of patients suffering severe hearing loss. This highly demanding concept, however, requires a strongly miniaturized device which is fully implantable in the middle/inner ear and includes the following components: frequency selective microphone or accelerometer, energy harvesting device, speech processor, and cochlear multielectrode. Here we demonstrate a low volume, piezoelectric micro-electromechanical system (MEMS cantilever array which is sensitive, even in the lower part of the voice frequency range (300–700 Hz. The test array consisting of 16 cantilevers has been fabricated by standard bulk micromachining using a Si-on-Insulator (SOI wafer and aluminum nitride (AlN as a complementary metal-oxide-semiconductor (CMOS and biocompatible piezoelectric material. The low frequency and low device footprint are ensured by Archimedean spiral geometry and Si seismic mass. Experimentally detected resonance frequencies were validated by an analytical model. The generated open circuit voltage (3–10 mV is sufficient for the direct analog conversion of the signals for cochlear multielectrode implants.

  11. Fully Implanted Brain-Computer Interface in a Locked-In Patient with ALS.

    Vansteensel, Mariska J; Pels, Elmar G M; Bleichner, Martin G; Branco, Mariana P; Denison, Timothy; Freudenburg, Zachary V; Gosselaar, Peter; Leinders, Sacha; Ottens, Thomas H; Van Den Boom, Max A; Van Rijen, Peter C; Aarnoutse, Erik J; Ramsey, Nick F

    2016-11-24

    Options for people with severe paralysis who have lost the ability to communicate orally are limited. We describe a method for communication in a patient with late-stage amyotrophic lateral sclerosis (ALS), involving a fully implanted brain-computer interface that consists of subdural electrodes placed over the motor cortex and a transmitter placed subcutaneously in the left side of the thorax. By attempting to move the hand on the side opposite the implanted electrodes, the patient accurately and independently controlled a computer typing program 28 weeks after electrode placement, at the equivalent of two letters per minute. The brain-computer interface offered autonomous communication that supplemented and at times supplanted the patient's eye-tracking device. (Funded by the Government of the Netherlands and the European Union; ClinicalTrials.gov number, NCT02224469 .).

  12. An NFC-Enabled CMOS IC for a Wireless Fully Implantable Glucose Sensor.

    DeHennis, Andrew; Getzlaff, Stefan; Grice, David; Mailand, Marko

    2016-01-01

    This paper presents an integrated circuit (IC) that merges integrated optical and temperature transducers, optical interface circuitry, and a near-field communication (NFC)-enabled digital, wireless readout for a fully passive implantable sensor platform to measure glucose in people with diabetes. A flip-chip mounted LED and monolithically integrated photodiodes serve as the transduction front-end to enable fluorescence readout. A wide-range programmable transimpedance amplifier adapts the sensor signals to the input of an 11-bit analog-to-digital converter digitizing the measurements. Measurement readout is enabled by means of wireless backscatter modulation to a remote NFC reader. The system is able to resolve current levels of less than 10 pA with a single fluorescent measurement energy consumption of less than 1 μJ. The wireless IC is fabricated in a 0.6-μm-CMOS process and utilizes a 13.56-MHz-based ISO15693 for passive wireless readout through a NFC interface. The IC is utilized as the core interface to a fluorescent, glucose transducer to enable a fully implantable sensor-based continuous glucose monitoring system.

  13. Implementation of integrated circuit and design of SAR ADC for fully implantable hearing aids.

    Kim, Jong Hoon; Lee, Jyung Hyun; Cho, Jin-Ho

    2017-07-20

    The hearing impaired population has been increasing; many people suffer from hearing problems. To deal with this difficulty, various types of hearing aids are being rapidly developed. In particular, fully implantable hearing aids are being actively studied to improve the performance of existing hearing aids and to reduce the stigma of hearing loss patients. It has to be of small size and low-power consumption for easy implantation and long-term use. The objective of the study was to implement a small size and low-power consumption successive approximation register analog-to-digital converter (SAR ADC) for fully implantable hearing aids. The ADC was selected as the SAR ADC because its analog circuit components are less required by the feedback circuit of the SAR ADC than the sigma-delta ADC which is conventionally used in hearing aids, and it has advantages in the area and power consumption. So, the circuit of SAR ADC is designed considering the speech region of humans because the objective is to deliver the speech signals of humans to hearing loss patients. If the switch of sample and hold works in the on/off positions, the charge injection and clock feedthrough are produced by a parasitic capacitor. These problems affect the linearity of the hold voltage, and as a result, an error of the bit conversion is generated. In order to solve the problem, a CMOS switch that consists of NMOS and PMOS was used, and it reduces the charge injection because the charge carriers in the NMOS and PMOS have inversed polarity. So, 16 bit conversion is performed before the occurrence of the Least Significant Bit (LSB) error. In order to minimize the offset voltage and power consumption of the designed comparator, we designed a preamplifier with current mirror. Therefore, the power consumption was reduced by the power control switch used in the comparator. The layout of the designed SAR ADC was performed by Virtuoso Layout Editor (Cadence, USA). In the layout result, the size of the

  14. Efficacy Study of a Fully Implanted Neuroprosthesis for Functional Benefit to Individuals with Tetraplegia

    2017-10-01

    and optimize the CNOW in autonomic nerves in ex-vivo guinea pig pulmonary nerves, for pulmonary applications. Training of Activity of Muscles Below...Impact…………………………………………………………… 5 5. Changes/Problems………………………………………………. 6 6. Products …………………………………………………………. 6 7. Participants & Other Collaborating...strategy that is specifically targeted for implantable devices in SCI, with the NNP hand system as the first product . Thus, we are now fully equipped and

  15. Chronic cortical and electromyographic recordings from a fully implantable device: preclinical experience in a nonhuman primate

    Ryapolova-Webb, Elena; Afshar, Pedram; Stanslaski, Scott; Denison, Tim; de Hemptinne, Coralie; Bankiewicz, Krystof; Starr, Philip A.

    2014-02-01

    Objective. Analysis of intra- and perioperatively recorded cortical and basal ganglia local field potentials in human movement disorders has provided great insight into the pathophysiology of diseases such as Parkinson's, dystonia, and essential tremor. However, in order to better understand the network abnormalities and effects of chronic therapeutic stimulation in these disorders, long-term recording from a fully implantable data collection system is needed. Approach. A fully implantable investigational data collection system, the Activa® PC + S neurostimulator (Medtronic, Inc., Minneapolis, MN), has been developed for human use. Here, we tested its utility for extended intracranial recording in the motor system of a nonhuman primate. The system was attached to two quadripolar paddle arrays: one covering sensorimotor cortex, and one covering a proximal forelimb muscle, to study simultaneous cortical field potentials and electromyography during spontaneous transitions from rest to movement. Main results. Over 24 months of recording, movement-related changes in physiologically relevant frequency bands were readily detected, including beta and gamma signals at approximately 2.5 μV/\\sqrtHz and 0.7 μV/\\sqrt{Hz}, respectively. The system architecture allowed for flexible recording configurations and algorithm triggered data recording. In the course of physiological analyses, sensing artifacts were observed (˜1 μVrms stationary tones at fixed frequency), which were mitigated either with post-processing or algorithm design and did not impact the scientific conclusions. Histological examination revealed no underlying tissue damage; however, a fibrous capsule had developed around the paddles, demonstrating a potential mechanism for the observed signal amplitude reduction. Significance. This study establishes the usefulness of this system in measuring chronic brain and muscle signals. Use of this system may potentially be valuable in human trials of chronic brain

  16. Tetherless near-infrared control of brain activity in behaving animals using fully implantable upconversion microdevices.

    Wang, Ying; Lin, Xudong; Chen, Xi; Chen, Xian; Xu, Zhen; Zhang, Wenchong; Liao, Qinghai; Duan, Xin; Wang, Xin; Liu, Ming; Wang, Feng; He, Jufang; Shi, Peng

    2017-10-01

    Many nanomaterials can be used as sensors or transducers in biomedical research and they form the essential components of transformative novel biotechnologies. In this study, we present an all-optical method for tetherless remote control of neural activity using fully implantable micro-devices based on upconversion technology. Upconversion nanoparticles (UCNPs) were used as transducers to convert near-infrared (NIR) energy to visible light in order to stimulate neurons expressing different opsin proteins. In our setup, UCNPs were packaged in a glass micro-optrode to form an implantable device with superb long-term biocompatibility. We showed that remotely applied NIR illumination is able to reliably trigger spiking activity in rat brains. In combination with a robotic laser projection system, the upconversion-based tetherless neural stimulation technique was implemented to modulate brain activity in various regions, including the striatum, ventral tegmental area, and visual cortex. Using this system, we were able to achieve behavioral conditioning in freely moving animals. Notably, our microscale device was at least one order of magnitude smaller in size (∼100 μm in diameter) and two orders of magnitude lighter in weight (less than 1 mg) than existing wireless optogenetic devices based on light-emitting diodes. This feature allows simultaneous implantation of multiple UCNP-optrodes to achieve modulation of brain function to control complex animal behavior. We believe that this technology not only represents a novel practical application of upconversion nanomaterials, but also opens up new possibilities for remote control of neural activity in the brains of behaving animals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. System overview of the fully implantable destination therapy--ReinHeart-total artificial heart.

    Pelletier, Benedikt; Spiliopoulos, Sotirios; Finocchiaro, Thomas; Graef, Felix; Kuipers, Kristin; Laumen, Marco; Guersoy, Dilek; Steinseifer, Ulrich; Koerfer, Reiner; Tenderich, Gero

    2015-01-01

    Owing to the lack of suitable allografts, the demand for long-term mechanical circulatory support in patients with biventricular end-stage heart failure is rising. Currently available Total Artificial Heart (TAH) systems consist of pump units with only limited durability, percutaneous tubes and bulky external equipment that limit the quality of life. Therefore we are focusing on the development of a fully implantable, highly durable destination therapy total artificial heart. The ReinHeart-TAH system consists of a passively filling pump unit driven by a low-wear linear drive between two artificial ventricles, an implantable control unit and a compliance chamber. The TAH is powered by a transcutaneous energy transmission system. The flow distribution inside the ventricles was analysed by fluid structure interaction simulation and particle image velocimetry measurements. Along with durability tests, the hydrodynamic performance and flow balance capability were evaluated in a mock circulation loop. Animal trials are ongoing. Based on fluid structure interaction simulation and particle image velocimetry, blood stagnation areas have been significantly reduced. In the mock circulation loop the ReinHeart-TAH generated a cardiac output of 5 l/min at an operating frequency of 120 bpm and an aortic pressure of 120/80 mmHg. The highly effective preload sensitivity of the passively filling ventricles allowed the sensorless integration of the Frank Starling mechanism. The ReinHeart-TAH effectively replaced the native heart's function in animals for up to 2 days. In vitro and in vivo testing showed a safe and effective function of the ReinHeart-TAH system. This has the potential to become an alternative to transplantation. However, before a first-in-man implant, chronic animal trials still have to be completed. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  18. Mastication noise reduction method for fully implantable hearing aid using piezo-electric sensor.

    Na, Sung Dae; Lee, Gihyoun; Wei, Qun; Seong, Ki Woong; Cho, Jin Ho; Kim, Myoung Nam

    2017-07-20

    Fully implantable hearing devices (FIHDs) can be affected by generated biomechanical noise such as mastication noise. To reduce the mastication noise using a piezo-electric sensor, the mastication noise is measured with the piezo-electric sensor, and noise reduction is practiced by the energy difference. For the experiment on mastication noise, a skull model was designed using artificial skull model and a piezo-electric sensor that can measure the vibration signals better than other sensors. A 1 kHz pure-tone sound through a standard speaker was applied to the model while the lower jawbone of the model was moved in a masticatory fashion. The correlation coefficients and signal-to-noise ratio (SNR) before and after application of the proposed method were compared. It was found that the signal-to-noise ratio and correlation coefficients increased by 4.48 dB and 0.45, respectively. The mastication noise is measured by piezo-electric sensor as the mastication noise that occurred during vibration. In addition, the noise was reduced by using the proposed method in conjunction with MATLAB. In order to confirm the performance of the proposed method, the correlation coefficients and signal-to-noise ratio before and after signal processing were calculated. In the future, an implantable microphone for real-time processing will be developed.

  19. Design and Evaluation of a Fully Implantable Control Unit for Blood Pumps

    Unthan, Kristin; Gräf, Felix; Laumen, Marco; Finocchiaro, Thomas; Sommer, Christoph; Lanmüller, Hermann; Steinseifer, Ulrich

    2015-01-01

    As the number of donor hearts is limited while more and more patients suffer from end stage biventricular heart failure, Total Artificial Hearts become a promising alternative to conventional treatment. While pneumatic devices sufficiently supply the patients with blood flow, the patient's quality of life is limited by the percutaneous pressure lines and the size of the external control unit. This paper describes the development of the control unit of the ReinHeart, a fully implantable Total Artificial Heart. General requirements for any implantable control unit are defined from a technical and medical point of view: necessity of a Transcutaneous Energy Transmission, autonomous operation, safety, geometry, and efficiency. Based on the requirements, a prototype is designed; it incorporates a LiFePo4 battery pack with charger, a rectifier for transcutaneous energy transmission, the motor's driver electronics, and a microcontroller which monitors and controls all functions. In validation tests, the control unit demonstrated a stable operation on TET and battery supply and a safe switching from one supply to the other. The overall mean efficiency is 14% on TET and 22% on battery supply. The control unit is suitable for chronic animal trials of the ReinHeart. PMID:26583095

  20. Fully refocused multi-shot spatiotemporally encoded MRI: robust imaging in the presence of metallic implants.

    Ben-Eliezer, Noam; Solomon, Eddy; Harel, Elad; Nevo, Nava; Frydman, Lucio

    2012-12-01

    An approach has been recently introduced for acquiring arbitrary 2D NMR spectra or images in a single scan, based on the use of frequency-swept RF pulses for the sequential excitation and acquisition of the spins response. This spatiotemporal-encoding (SPEN) approach enables a unique, voxel-by-voxel refocusing of all frequency shifts in the sample, for all instants throughout the data acquisition. The present study investigates the use of this full-refocusing aspect of SPEN-based imaging in the multi-shot MRI of objects, subject to sizable field inhomogeneities that complicate conventional imaging approaches. 2D MRI experiments were performed at 7 T on phantoms and on mice in vivo, focusing on imaging in proximity to metallic objects. Fully refocused SPEN-based spin echo imaging sequences were implemented, using both Cartesian and back-projection trajectories, and compared with k-space encoded spin echo imaging schemes collected on identical samples under equal bandwidths and acquisition timing conditions. In all cases assayed, the fully refocused spatiotemporally encoded experiments evidenced a ca. 50 % reduction in signal dephasing in the proximity of the metal, as compared to analogous results stemming from the k-space encoded spin echo counterparts. The results in this study suggest that SPEN-based acquisition schemes carry the potential to overcome strong field inhomogeneities, of the kind that currently preclude high-field, high-resolution tissue characterizations in the neighborhood of metallic implants.

  1. Intracorporeal Heat Distribution from Fully Implantable Energy Sources for Mechanical Circulatory Support: A Computational Proof-of-Concept Study

    Biasetti, Jacopo; Pustavoitau, Aliaksei; Spazzini, Pier Giorgio

    2017-01-01

    Mechanical circulatory support devices, such as total artificial hearts and left ventricular assist devices, rely on external energy sources for their continuous operation. Clinically approved power supplies rely on percutaneous cables connecting an external energy source to the implanted device with the associated risk of infections. One alternative, investigated in the 70s and 80s, employs a fully implanted nuclear power source. The heat generated by the nuclear decay can be converted into ...

  2. Cochlear implantation in Mondini's deformity: could the straight electrode array with length of 31 mm be fully inserted?

    Sun, Jia-Qiang; Sun, Jing-Wu; Hou, Xiao-Yan

    2017-07-01

    The straight electrode array with length of 31 mm can be fully inserted using round window insertion in cochlear implantation with Mondini's deformity. It is a safe and effective process, but also a challenging task of the full implantation in children with Mondini's deformity. The aim of this study is to discuss whether the straight electrode array with a length of 31 mm could be fully inserted in cochlear implantation with Mondini's deformity. A chart review of 30 patients undergoing cochlear implantation with Mondini's deformity using the electrode array with length of 31 mm was undertaken from January 2012 and December 2015 in Anhui Provincial Hospital. Full insertion of the straight electrode array with length of 31 mm were performed successfully in all patients with Mondini's deformity using round window insertion. Resistance was not encountered while introducing the electrodes. Ten of 30 patients had cerebrospinal fluid drainage during cochlear implantation. Cerebrospinal fluid drainage was controlled with small pieces of temporalis fascia packing round window in all patients. Intra-operative neural response telemetry was performed in all patients, and results were good. The result of X-ray showed proper placement of the cochlear implant electrode array. During surgery, no patients had experienced any immediate or delayed post-operative complications such as wound infection, intracranial complication, extrusion, or migration of the implant during an average follow-up period of 6-36 months.

  3. A fully digital approach to replicate peri-implant soft tissue contours and emergence profile in the esthetic zone.

    Monaco, Carlo; Evangelisti, Edoardo; Scotti, Roberto; Mignani, Giuseppe; Zucchelli, Giovanni

    2016-12-01

    This short communication reports on a novel digital technique designated - the "Fully Digital Technique (FDT)" - to take the impression of the peri-implant soft tissue and emergence profile with an intraoral scanner, digitally capturing both the three dimensional position of the implant platform and the coronal and gingival parts of the provisional retained restoration. A first intraoral digital impression, which generated a standard triangulation language file (STL1), was taken using a standardized implant scanbody to detect the position of the implant. A second digital impression (STL2) with the provisional retained restoration in situ was performed in two steps: the first part of the scan captured all details of the vestibular and palatal sides of the provisional retained restoration and the adjacent teeth. The provisional retained restoration was then unscrewed, and the subgingival part of the restoration was scanned directly out of the mouth to determine its subgingival shape. STL1 and STL2 were imported into imaging software and superimposed using the "best fit" algorithm to achieve a new merged file (STL3) with the 3D implant position, the peri-implant mucosa, and emergence profile. The merged file was used to design the CAD/CAM customized abutment and to realize a stereolithographic model by 3D printing. The STL superimposition of digital impressions of the implant position and the provisional retained restoration constitute a novel technique to obtain a single STL file with the implant position and its peri-implant mucosal architecture. FDT is a rapid digital approach for achieving all information of the peri-implant soft tissue and emergence profile directly from the provisional retained restoration. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Characterization of a Polymer-Based, Fully Organic Prosthesis for Implantation into the Subretinal Space of the Rat.

    Antognazza, Maria Rosa; Di Paolo, Mattia; Ghezzi, Diego; Mete, Maurizio; Di Marco, Stefano; Maya-Vetencourt, José Fernando; Maccarone, Rita; Desii, Andrea; Di Fonzo, Fabio; Bramini, Mattia; Russo, Angela; Laudato, Lucia; Donelli, Ilaria; Cilli, Michele; Freddi, Giuliano; Pertile, Grazia; Lanzani, Guglielmo; Bisti, Silvia; Benfenati, Fabio

    2016-09-01

    Replacement strategies arise as promising approaches in case of inherited retinal dystrophies leading to blindness. A fully organic retinal prosthesis made of conjugated polymers layered onto a silk fibroin substrate is engineered. First, the biophysical and surface properties are characterized; then, the long-term biocompatibility is assessed after implantation of the organic device in the subretinal space of 3-months-old rats for a period of five months. The results indicate a good stability of the subretinal implants over time, with preservation of the physical properties of the polymeric layer and a tight contact with the outer retina. Immunoinflammatory markers detect only a modest tissue reaction to the surgical insult and the foreign body that peaks shortly after surgery and progressively decreases with time to normal levels at five months after implantation. Importantly, the integrity of the polymeric layer in direct contact with the retinal tissue is preserved after five months of implantation. The recovery of the foreign-body tissue reaction is also associated with a normal b-wave in the electroretinographic response. The results demonstrate that the device implanted in nondystrophic eyes is well tolerated, highly biocompatible, and suitable as retinal prosthesis in case of photoreceptor degeneration. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Miniature Coplanar Implantable Antenna on Thin and Flexible Platform for Fully Wireless Intracranial Pressure Monitoring System

    M. Waqas A. Khan

    2017-01-01

    Full Text Available Minimally invasive approach to intracranial pressure monitoring is desired for long-term diagnostics. The monitored pressure is transmitted outside the skull through an implant antenna. We present a new miniature (6 mm × 5 mm coplanar implant antenna and its integration on a sensor platform to establish a far-field data link for the sensor readout at distances of 0.5 to 1 meter. The implant antenna was developed using full-wave electromagnetic simulator and measured in a liquid phantom mimicking the dielectric properties of the human head. It achieved impedance reflection coefficient better than −10 dB from 2.38 GHz to 2.54 GHz which covers the targeted industrial, scientific, and medical band. Experiments resulted in an acceptable peak gain of approximately −23 dBi. The implant antenna was submerged in the liquid phantom and interfaced to a 0.5 mW voltage controlled oscillator. To verify the implant antenna performance as a part of the ICP monitoring system, we recorded the radiated signal strength using a spectrum analyzer. Using a half-wavelength dipole as the receiving antenna, we captured approximately −58.7 dBm signal at a distance of 1 m from the implant antenna which is well above for the reader with sensitivity of −80 dBm.

  6. 10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients

    van Velzen, F.J.J.; Ofec, R.; Schulten, E.A.J.M.; ten Bruggenkate, C.M.

    2015-01-01

    Purpose This prospective cohort study evaluates the 10-year survival and incidence of peri-implant disease at implant and patient level of sandblasted, large grid, and acid-etched titanium dental implants (Straumann, soft tissue level, SLA surface) in fully and partially edentulous patients.

  7. A Fully Implantable Stimulator With Wireless Power and Data Transmission for Experimental Investigation of Epidural Spinal Cord Stimulation.

    Xu, Qi; Hu, Dingyin; Duan, Bingyu; He, Jiping

    2015-07-01

    Epidural spinal cord stimulation (ESCS) combined with partial weight-bearing therapy (PWBT) has been shown to facilitate recovery of functional walking for individuals after spinal cord injury (SCI). The investigation of neural mechanisms of recovery from SCI under this treatment has been conducted broadly in rodent models, yet a suitable ESCS system is still unavailable. This paper describes a practical, programmable, and fully implantable stimulator for laboratory research on rats to explore fundamental neurophysiological principles for functional recovery after SCI. The ESCS system is composed of a personal digital assistant (PDA), an external controller, an implantable pulse generator (IPG), lead extension, and stimulating electrodes. The stimulation parameters can be programmed and adjusted through a graphical user interface on the PDA. The external controller is placed on the rat back and communicates with the PDA via radio-frequency (RF) telemetry. An RF carrier from the class-E power amplifier in the external controller provides both data and power for the IPG through an inductive link. The IPG is built around a microcontroller unit to generate voltage-regulated pulses delivered to the bipolar electrode for ESCS in rats. The encapsulated IPG measures 22 mm × 23 mm × 7 mm with a mass of  ∼  3.78 g. This fully implantable batteryless stimulator provided a simplified and efficient method to carry out chronic experiments in untethered animals for medical electro-neurological research.

  8. 10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients.

    van Velzen, Frank J J; Ofec, Ronen; Schulten, Engelbert A J M; Ten Bruggenkate, Christiaan M

    2015-10-01

    This prospective cohort study evaluates the 10-year survival and incidence of peri-implant disease at implant and patient level of sandblasted, large grid, and acid-etched titanium dental implants (Straumann, soft tissue level, SLA surface) in fully and partially edentulous patients. Patients who had dental implant surgery in the period between November 1997 and June 2001, with a follow-up of at least 10 years, were investigated for clinical and radiological examination. Among the 506 inserted dental implants in 250 patients, 10-year data regarding the outcome of implants were available for 374 dental implants in 177 patients. In the current study, peri-implantitis was defined as advanced bone loss (≧1.5 mm. postloading) in combination with bleeding on probing. At 10-year follow-up, only one implant was lost (0.3%) 2 months after implant surgery due to insufficient osseointegration. The average bone loss at 10 year postloading was 0.52 mm. Advanced bone loss at 10-year follow-up was present in 35 dental implants (9.8%). Seven percent of the observed dental implants showed bleeding on probing in combination with advanced bone loss and 4.2% when setting the threshold for advanced bone loss at 2.0 mm. Advanced bone loss without bleeding on probing was present in 2.8% of all implants. In this prospective study, the 10-year survival rate at implant and patient level was 99.7% and 99.4%, respectively. Peri-implantitis was present in 7% of the observed dental implants according to the above-mentioned definition of peri-implantitis. This study shows that SLA implants offer predictable long-term results as support in the treatment of fully and partially edentulous patients. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Efficacy Study of a Fully Implanted Neuroprosthesis for Functional Benefit to Individuals with Tetraplegia

    2016-10-01

    for our research subjects that is adjacent to our rehabilitation hospital and to our research laboratories. This facility essentially serves as a...SCI, and includes fully accessible bedrooms, bathrooms, and kitchen ; as well as motorized ceiling-mounted patient lifts, roll-in showers, and

  10. Fully digital data processing during cardiovascular implantable electronic device follow-up in a high-volume tertiary center.

    Staudacher, Ingo; Nalpathamkalam, Asha Roy; Uhlmann, Lorenz; Illg, Claudius; Seehausen, Sebastian; Akhavanpoor, Mohammadreza; Buchauer, Anke; Geis, Nicolas; Lugenbiel, Patrick; Schweizer, Patrick A; Xynogalos, Panagiotis; Zylla, Maura M; Scholz, Eberhard; Zitron, Edgar; Katus, Hugo A; Thomas, Dierk

    2017-10-11

    Increasing numbers of patients with cardiovascular implantable electronic devices (CIEDs) and limited follow-up capacities highlight unmet challenges in clinical electrophysiology. Integrated software (MediConnect ® ) enabling fully digital processing of device interrogation data has been commercially developed to facilitate follow-up visits. We sought to assess feasibility of fully digital data processing (FDDP) during ambulatory device follow-up in a high-volume tertiary hospital to provide guidance for future users of FDDP software. A total of 391 patients (mean age, 70 years) presenting to the outpatient department for routine device follow-up were analyzed (pacemaker, 44%; implantable cardioverter defibrillator, 39%; cardiac resynchronization therapy device, 16%). Quality of data transfer and follow-up duration were compared between digital (n = 265) and manual processing of device data (n = 126). Digital data import was successful, complete and correct in 82% of cases when early software versions were used. When using the most recent software version the rate of successful digital data import increased to 100%. Software-based import of interrogation data was complete and without failure in 97% of cases. The mean duration of a follow-up visit did not differ between the two groups (digital 18.7 min vs. manual data transfer 18.2 min). FDDP software was successfully implemented into the ambulatory follow-up of patients with implanted pacemakers and defibrillators. Digital data import into electronic patient management software was feasible and supported the physician's workflow. The total duration of follow-up visits comprising technical device interrogation and clinical actions was not affected in the present tertiary center outpatient cohort.

  11. Neurofeedback Control in Parkinsonian Patients Using Electrocorticography Signals Accessed Wirelessly With a Chronic, Fully Implanted Device.

    Khanna, Preeya; Swann, Nicole C; de Hemptinne, Coralie; Miocinovic, Svjetlana; Miller, Andrew; Starr, Philip A; Carmena, Jose M

    2017-10-01

    Parkinson's disease (PD) is characterized by motor symptoms such as rigidity and bradykinesia that prevent normal movement. Beta band oscillations (13-30 Hz) in neural local field potentials (LFPs) have been associated with these motor symptoms. Here, three PD patients implanted with a therapeutic deep brain neural stimulator that can also record and wirelessly stream neural data played a neurofeedback game where they modulated their beta band power from sensorimotor cortical areas. Patients' beta band power was streamed in real-time to update the position of a cursor that they tried to drive into a cued target. After playing the game for 1-2 hours each, all three patients exhibited above chance-level performance regardless of subcortical stimulation levels. This study, for the first time, demonstrates using an invasive neural recording system for at-home neurofeedback training. Future work will investigate chronic neurofeedback training as a potentially therapeutic tool for patients with neurological disorders.

  12. In Vivo Tooth-Supported Implant Surgical Guides Fabricated With Desktop Stereolithographic Printers: Fully Guided Surgery Is More Accurate Than Partially Guided Surgery.

    Bencharit, Sompop; Staffen, Adam; Yeung, Matthew; Whitley, Daniel; Laskin, Daniel M; Deeb, George R

    2018-02-21

    Desktop stereolithographic printers combined with intraoral scanning and implant planning software promise precise and cost-effective guided implant surgery. The purpose of the present study was to determine the overall range of accuracy of tooth-supported guided implant surgery using desktop printed stereolithographic guides. A cross-sectional study comparing fully and partially guided implant surgery was conducted. Preoperative cone beam computed tomography (CBCT) and intraoral scans were used to plan the implant sites. Surgical guides were then fabricated using a desktop stereolithographic 3-dimensional printer. Postoperative CBCT was used to evaluate the accuracy of placement. Deviations from the planned positions were used as the primary outcome variables. The planning software used, implant systems, and anterior/posterior positions were the secondary outcome variables. The differences between the planned and actual implant positions in the mesial, distal, buccal, and lingual dimensions and buccolingual angulations were determined, and the accuracy was compared statistically using the 1-tail F-test (P = .01), box plots, and 95% confidence intervals for the mean. Sixteen partially edentulous patients requiring placement of 31 implants were included in the present study. The implant deviations from the planned positions for mesial, distal, buccal, and lingual dimensions and buccolingual angulations with the fully guided protocol (n = 20) were 0.17 ± 0.78 mm, 0.44 ± 0.78 mm, 0.23 ± 1.08 mm, -0.22 ± 1.44 mm, and -0.32° ± 2.36°, respectively. The corresponding implant deviations for the partially guided protocol (n = 11) were 0.33 ± 1.38 mm, -0.03 ± 1.59 mm, 0.62 ± 1.15 mm, -0.27 ± 1.61 mm, and 0.59° ± 6.83°. The difference between the variances for fully and partially guided surgery for the distal and angulation dimensions was statistically significant (P = .006 and P guided implant surgery is more accurate than

  13. Intracorporeal Heat Distribution from Fully Implantable Energy Sources for Mechanical Circulatory Support: A Computational Proof-of-Concept Study

    Jacopo Biasetti

    2017-10-01

    Full Text Available Mechanical circulatory support devices, such as total artificial hearts and left ventricular assist devices, rely on external energy sources for their continuous operation. Clinically approved power supplies rely on percutaneous cables connecting an external energy source to the implanted device with the associated risk of infections. One alternative, investigated in the 70s and 80s, employs a fully implanted nuclear power source. The heat generated by the nuclear decay can be converted into electricity to power circulatory support devices. Due to the low conversion efficiencies, substantial levels of waste heat are generated and must be dissipated to avoid tissue damage, heat stroke, and death. The present work computationally evaluates the ability of the blood flow in the descending aorta to remove the locally generated waste heat for subsequent full-body distribution and dissipation, with the specific aim of investigating methods for containment of local peak temperatures within physiologically acceptable limits. To this aim, coupled fluid–solid heat transfer computational models of the blood flow in the human aorta and different heat exchanger architectures are developed. Particle tracking is used to evaluate temperature histories of cells passing through the heat exchanger region. The use of the blood flow in the descending aorta as a heat sink proves to be a viable approach for the removal of waste heat loads. With the basic heat exchanger design, blood thermal boundary layer temperatures exceed 50°C, possibly damaging blood cells and proteins. Improved designs of the heat exchanger, with the addition of fins and heat guides, allow for drastically lower blood temperatures, possibly leading to a more biocompatible implant. The ability to maintain blood temperatures at biologically compatible levels will ultimately allow for the body-wise distribution, and subsequent dissipation, of heat loads with minimum effects on the human physiology.

  14. Intracorporeal Heat Distribution from Fully Implantable Energy Sources for Mechanical Circulatory Support: A Computational Proof-of-Concept Study.

    Biasetti, Jacopo; Pustavoitau, Aliaksei; Spazzini, Pier Giorgio

    2017-01-01

    Mechanical circulatory support devices, such as total artificial hearts and left ventricular assist devices, rely on external energy sources for their continuous operation. Clinically approved power supplies rely on percutaneous cables connecting an external energy source to the implanted device with the associated risk of infections. One alternative, investigated in the 70s and 80s, employs a fully implanted nuclear power source. The heat generated by the nuclear decay can be converted into electricity to power circulatory support devices. Due to the low conversion efficiencies, substantial levels of waste heat are generated and must be dissipated to avoid tissue damage, heat stroke, and death. The present work computationally evaluates the ability of the blood flow in the descending aorta to remove the locally generated waste heat for subsequent full-body distribution and dissipation, with the specific aim of investigating methods for containment of local peak temperatures within physiologically acceptable limits. To this aim, coupled fluid-solid heat transfer computational models of the blood flow in the human aorta and different heat exchanger architectures are developed. Particle tracking is used to evaluate temperature histories of cells passing through the heat exchanger region. The use of the blood flow in the descending aorta as a heat sink proves to be a viable approach for the removal of waste heat loads. With the basic heat exchanger design, blood thermal boundary layer temperatures exceed 50°C, possibly damaging blood cells and proteins. Improved designs of the heat exchanger, with the addition of fins and heat guides, allow for drastically lower blood temperatures, possibly leading to a more biocompatible implant. The ability to maintain blood temperatures at biologically compatible levels will ultimately allow for the body-wise distribution, and subsequent dissipation, of heat loads with minimum effects on the human physiology.

  15. Fully 3-dimensional digitally planned reconstruction of a mandible with a free vascularized fibula and immediate placement of an implant-supported prosthetic construction

    Schepers, Rutger H.; Raghoebar, Gerry M.; Vissink, Arjan; Lahoda, Lars U.; Van der Meer, W. Joerd; Roodenburg, Jan L.; Reintsema, Harry; Witjes, Max J.

    Background Reconstruction of craniofacial defects becomes complex when dental implants are included for functional rehabilitation. We describe a fully 3-dimensional (3D) digitally planned reconstruction of a mandible and immediate prosthetic loading with a fibula graft in a 2-step surgical approach.

  16. Fully Implantable Deep Brain Stimulation System with Wireless Power Transmission for Long-term Use in Rodent Models of Parkinson's Disease.

    Heo, Man Seung; Moon, Hyun Seok; Kim, Hee Chan; Park, Hyung Woo; Lim, Young Hoon; Paek, Sun Ha

    2015-03-01

    The purpose of this study to develop new deep-brain stimulation system for long-term use in animals, in order to develop a variety of neural prostheses. Our system has two distinguished features, which are the fully implanted system having wearable wireless power transfer and ability to change the parameter of stimulus parameter. It is useful for obtaining a variety of data from a long-term experiment. To validate our system, we performed pre-clinical test in Parkinson's disease-rat models for 4 weeks. Through the in vivo test, we observed the possibility of not only long-term implantation and stability, but also free movement of animals. We confirmed that the electrical stimulation neither caused any side effect nor damaged the electrodes. We proved possibility of our system to conduct the long-term pre-clinical test in variety of parameter, which is available for development of neural prostheses.

  17. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease

    Onuma, Yoshinobu; Dudek, Dariusz; Thuesen, Leif

    2013-01-01

    This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California).......This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California)....

  18. Brachial insertion of fully implantable venous catheters for chemotherapy: complications and quality of life assessment in 35 patients.

    Fonseca, Igor Yoshio Imagawa; Krutman, Mariana; Nishinari, Kenji; Yazbek, Guilherme; Teivelis, Marcelo Passos; Bomfim, Guilherme André Zottele; Cavalcante, Rafael Noronha; Wolosker, Nelson

    2016-01-01

    To prospectively evaluate the perioperative safety, early complications and satisfaction of patients who underwent the implantation of central catheters peripherally inserted via basilic vein. Thirty-five consecutive patients with active oncologic disease requiring chemotherapy were prospectively followed up after undergoing peripheral implantation of indwelling venous catheters, between November 2013 and June 2014. The procedures were performed in the operating room by the same team of three vascular surgeons. The primary endpoints assessed were early postoperative complications, occurring within 30 days after implantation. The evaluation of patient satisfaction was based on a specific questionnaire used in previous studies. In all cases, ultrasound-guided puncture of the basilic vein was feasible and the procedure successfully completed. Early complications included one case of basilic vein thrombophlebitis and one case of pocket infection that did not require device removal. Out of 35 patients interviewed, 33 (94.3%) would recommend the device to other patients. Implanting brachial ports is a feasible option, with low intraoperative risk and similar rates of early postoperative complications when compared to the existing data of the conventional technique. The patients studied were satisfied with the device and would recommend the procedure to others. Avaliar prospectivamente segurança perioperatória, complicações precoces e grau de satisfação de pacientes submetidos ao implante de cateteres centrais de inserção periférica pela veia basílica. Foram acompanhados prospectivamente e submetidos ao implante de cateteres de longa permanência de inserção periférica, entre novembro de 2013 e junho de 2014, 35 pacientes consecutivos com doença oncológica ativa necessitando de quimioterapia. Os procedimentos foram realizados em centro cirúrgico por uma mesma equipe composta por três cirurgiões vasculares. Os desfechos primários avaliados foram as

  19. First-in-man demonstration of a fully implanted myoelectric sensors system to control an advanced electromechanical prosthetic hand.

    Pasquina, Paul F; Evangelista, Melissa; Carvalho, A J; Lockhart, Joseph; Griffin, Sarah; Nanos, George; McKay, Patricia; Hansen, Morten; Ipsen, Derek; Vandersea, James; Butkus, Josef; Miller, Matthew; Murphy, Ian; Hankin, David

    2015-04-15

    Advanced motorized prosthetic devices are currently controlled by EMG signals generated by residual muscles and recorded by surface electrodes on the skin. These surface recordings are often inconsistent and unreliable, leading to high prosthetic abandonment rates for individuals with upper limb amputation. Surface electrodes are limited because of poor skin contact, socket rotation, residual limb sweating, and their ability to only record signals from superficial muscles, whose function frequently does not relate to the intended prosthetic function. More sophisticated prosthetic devices require a stable and reliable interface between the user and robotic hand to improve upper limb prosthetic function. Implantable Myoelectric Sensors (IMES(®)) are small electrodes intended to detect and wirelessly transmit EMG signals to an electromechanical prosthetic hand via an electro-magnetic coil built into the prosthetic socket. This system is designed to simultaneously capture EMG signals from multiple residual limb muscles, allowing the natural control of multiple degrees of freedom simultaneously. We report the status of the first FDA-approved clinical trial of the IMES(®) System. This study is currently in progress, limiting reporting to only preliminary results. Our first subject has reported the ability to accomplish a greater variety and complexity of tasks in his everyday life compared to what could be achieved with his previous myoelectric prosthesis. The interim results of this study indicate the feasibility of utilizing IMES(®) technology to reliably sense and wirelessly transmit EMG signals from residual muscles to intuitively control a three degree-of-freedom prosthetic arm. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. A 96-channel FPGA-based Time-to-Digital Converter (TDC) and fast trigger processor module with multi-hit capability and pipeline

    Bogdan, Mircea; Frisch, Henry; Heintz, Mary; Paramonov, Alexander; Sanders, Harold; Chappa, Steve; DeMaat, Robert; Klein, Rod; Miao, Ting; Wilson, Peter; Phillips, Thomas J.

    2005-01-01

    We describe an field-programmable gate arrays based (FPGA), 96-channel, Time-to-Digital converter (TDC) and trigger logic board intended for use with the Central Outer Tracker (COT) [T. Affolder et al., Nucl. Instr. and Meth. A 526 (2004) 249] in the CDF Experiment [The CDF-II detector is described in the CDF Technical Design Report (TDR), FERMILAB-Pub-96/390-E. The TDC described here is intended as a further upgrade beyond that described in the TDR] at the Fermilab Tevatron. The COT system is digitized and read out by 315 TDC cards, each serving 96 wires of the chamber. The TDC is physically configured as a 9U VME card. The functionality is almost entirely programmed in firmware in two Altera Stratix FPGAs. The special capabilities of this device are the availability of 840MHz LVDS inputs, multiple phase-locked clock modules, and abundant memory. The TDC system operates with an input resolution of 1.2ns, a minimum input pulse width of 4.8ns and a minimum separation of 4.8ns between pulses. Each input can accept up to 7 hits per collision. The time-to-digital conversion is done by first sampling each of the 96 inputs in 1.2-ns bins and filling a circular memory; the memory addresses of logical transitions (edges) in the input data are then translated into the time of arrival and width of the COT pulses. Memory pipelines with a depth of 5.5μs allow deadtime-less operation in the first-level trigger; the data are multiple-buffered to diminish deadtime in the second-level trigger. The complete process of edge-detection and filling of buffers for readout takes 12μs. The TDC VME interface allows a 64-bit Chain Block Transfer of multiple boards in a crate with transfer-rates up to 47Mbytes/s. The TDC module also produces prompt trigger data every Tevatron crossing via a deadtimeless fast logic path that can be easily reprogrammed. The trigger bits are clocked onto the P3 VME backplane connector with a 22-ns clock for transmission to the trigger. The full TDC design and

  1. Predictors of Paravalvular Regurgitation After Implantation of the Fully Repositionable and Retrievable Lotus Transcatheter Aortic Valve (from the REPRISE II Trial Extended Cohort).

    Blackman, Daniel J; Meredith, Ian T; Dumonteil, Nicolas; Tchétché, Didier; Hildick-Smith, David; Spence, Mark S; Walters, Darren L; Harnek, Jan; Worthley, Stephen G; Rioufol, Gilles; Lefèvre, Thierry; Houle, Vicki M; Allocco, Dominic J; Dawkins, Keith D

    2017-07-15

    Paravalvular leak (PVL) after transcatheter aortic valve replacement is associated with worse long-term outcomes. The Lotus Valve incorporates an innovative Adaptive Seal designed to minimize PVL. This analysis evaluated the incidence and predictors of PVL after implantation of the Lotus transcatheter aortic valve. The REPRISE II (REpositionable Percutaneous Replacement of Stenotic Aortic Valve through Implantation of Lotus Valve System - Evaluation of Safety and Performance) Study With Extended Cohort enrolled 250 high-surgical risk patients with severe symptomatic aortic stenosis. Aortic regurgitation was assessed by echocardiography pre-procedure, at discharge and 30 days, by an independent core laboratory. Baseline and procedural predictors of mild or greater PVL at 30 days (or at discharge if 30-day data were not available) were determined using a multivariate regression model (n = 229). Of the 229 patients, 197 (86%) had no/trace PVL, 30 had mild, and 2 had moderate PVL; no patient had severe PVL. Significant predictors of mild/moderate PVL included device:annulus area ratio (odds ratio [OR] 0.87; 95% CI 0.83 to 0.92; p 10% annular oversizing by area were 17.5% (11 of 63), 2.9% (2 of 70), and 3.2% (2 of 63), respectively. Significant independent predictors of PVL included device:annulus area ratio and left ventricular outflow tract calcium volume. When the prosthetic valve was oversized by ≥5%, the rate of mild or greater PVL was only 3%. In conclusion, the overall rates of PVL with the Lotus Valve are low and predominantly related to device/annulus areas and calcium; these findings have implications for optimal device sizing. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease: the ABSORB cohort A trial.

    Onuma, Yoshinobu; Dudek, Dariusz; Thuesen, Leif; Webster, Mark; Nieman, Koen; Garcia-Garcia, Hector M; Ormiston, John A; Serruys, Patrick W

    2013-10-01

    This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California). Multimodality imaging of the first-in-humans trial using a ABSORB BVS scaffold demonstrated at 2 years the bioresorption of the device while preventing restenosis. However, the long-term safety and efficacy of this therapy remain to be documented. In the ABSORB cohort A trial (ABSORB Clinical Investigation, Cohort A [ABSORB A] Everolimus-Eluting Coronary Stent System Clinical Investigation), 30 patients with a single de novo coronary artery lesion were treated with the fully resorbable everolimus-eluting Absorb scaffold at 4 centers. As an optional investigation in 3 of the 4 centers, the patients underwent multislice computed tomography (MSCT) angiography at 18 months and 5 years. Acquired MSCT data were analyzed at an independent core laboratory (Cardialysis, Rotterdam, the Netherlands) for quantitative analysis of lumen dimensions and was further processed for calculation of fractional flow reserve (FFR) at another independent core laboratory (Heart Flow, Redwood City, California). Five-year clinical follow-up is available for 29 patients. One patient withdrew consent after 6 months, but the vital status of this patient remains available. At 46 days, 1 patient experienced a single episode of chest pain and underwent a target lesion revascularization with a slight troponin increase after the procedure. At 5 years, the ischemia-driven major adverse cardiac event rate of 3.4% remained unchanged. Clopidogrel was discontinued in all but 1 patient. Scaffold thrombosis was not observed in any patient. Two noncardiac deaths were reported, 1 caused by duodenal perforation and the other from Hodgkin's disease. At 5 years, 18 patients underwent MSCT angiography. All scaffolds were patent, with a median minimal lumen area of 3

  3. Retrograde peri-implantitis

    Mohamed Jumshad

    2010-01-01

    Full Text Available Retrograde peri-implantitis constitutes an important cause for implant failure. Retrograde peri-implantitis may sometimes prove difficult to identify and hence institution of early treatment may not be possible. This paper presents a report of four cases of (the implant placed developing to retrograde peri-implantitis. Three of these implants were successfully restored to their fully functional state while one was lost due to extensive damage. The paper highlights the importance of recognizing the etiopathogenic mechanisms, preoperative assessment, and a strong postoperative maintenance protocol to avoid retrograde peri-implant inflammation.

  4. Ion implantation

    Dearnaley, Geoffrey

    1975-01-01

    First, ion implantation in semiconductors is discussed: ion penetration, annealing of damage, gettering, ion implanted semiconductor devices, equipement requirements for ion implantation. The importance of channeling for ion implantation is studied. Then, some applications of ion implantation in metals are presented: study of the corrosion of metals and alloys; influence or ion implantation on the surface-friction and wear properties of metals; hyperfine interactions in implanted metals

  5. Primary prevention of peri-implantitis: Managing peri-implant mucositis

    Jepsen, Søren; Berglundh, Tord; Genco, Robert; Aass, Anne Merete; Demirel, Korkud; Derks, Jan; Figuero, Elena; Giovannoli, Jean Louis; Goldstein, Moshe; LAMBERT, France; Ortiz-Vigon, Alberto; Polyzois, Ioannis; Salvi, Giovanni; Schwarz, Frank; Serino, Giovanni

    2015-01-01

    Abstract AIMS: Over the past decades, the placement of dental implants has become a routine procedure in the oral rehabilitation of fully and partially edentulous patients. However, the number of patients/implants affected by peri-implant diseases is increasing. As there are--in contrast to periodontitis--at present no established and predictable concepts for the treatment of peri-implantitis, primary prevention is of key importance. The management of peri-implant mucositis is considere...

  6. Fully Integrated Biochip Platforms for Advanced Healthcare

    Giovanni De Micheli

    2012-08-01

    Full Text Available Recent advances in microelectronics and biosensors are enabling developments of innovative biochips for advanced healthcare by providing fully integrated platforms for continuous monitoring of a large set of human disease biomarkers. Continuous monitoring of several human metabolites can be addressed by using fully integrated and minimally invasive devices located in the sub-cutis, typically in the peritoneal region. This extends the techniques of continuous monitoring of glucose currently being pursued with diabetic patients. However, several issues have to be considered in order to succeed in developing fully integrated and minimally invasive implantable devices. These innovative devices require a high-degree of integration, minimal invasive surgery, long-term biocompatibility, security and privacy in data transmission, high reliability, high reproducibility, high specificity, low detection limit and high sensitivity. Recent advances in the field have already proposed possible solutions for several of these issues. The aim of the present paper is to present a broad spectrum of recent results and to propose future directions of development in order to obtain fully implantable systems for the continuous monitoring of the human metabolism in advanced healthcare applications.

  7. Fully integrated biochip platforms for advanced healthcare.

    Carrara, Sandro; Ghoreishizadeh, Sara; Olivo, Jacopo; Taurino, Irene; Baj-Rossi, Camilla; Cavallini, Andrea; de Beeck, Maaike Op; Dehollain, Catherine; Burleson, Wayne; Moussy, Francis Gabriel; Guiseppi-Elie, Anthony; De Micheli, Giovanni

    2012-01-01

    Recent advances in microelectronics and biosensors are enabling developments of innovative biochips for advanced healthcare by providing fully integrated platforms for continuous monitoring of a large set of human disease biomarkers. Continuous monitoring of several human metabolites can be addressed by using fully integrated and minimally invasive devices located in the sub-cutis, typically in the peritoneal region. This extends the techniques of continuous monitoring of glucose currently being pursued with diabetic patients. However, several issues have to be considered in order to succeed in developing fully integrated and minimally invasive implantable devices. These innovative devices require a high-degree of integration, minimal invasive surgery, long-term biocompatibility, security and privacy in data transmission, high reliability, high reproducibility, high specificity, low detection limit and high sensitivity. Recent advances in the field have already proposed possible solutions for several of these issues. The aim of the present paper is to present a broad spectrum of recent results and to propose future directions of development in order to obtain fully implantable systems for the continuous monitoring of the human metabolism in advanced healthcare applications.

  8. Selective laser-melted fully biodegradable scaffold composed of poly(d,l-lactide) and β-tricalcium phosphate with potential as a biodegradable implant for complex maxillofacial reconstruction: In vitro and in vivo results.

    Smeets, Ralf; Barbeck, Mike; Hanken, Henning; Fischer, Horst; Lindner, Markus; Heiland, Max; Wöltje, Michael; Ghanaati, Shahram; Kolk, Andreas

    2017-07-01

    Scaffolds (SC) composed of poly(d,l-lactide) and β-tricalcium phosphate of variable pore structures were manufactured by selective laser melting (SLM), which allowed the production of porous interconnected structures promoting cellular adhesion and vascular proliferation. Biocompatibility, rate of osseointegration and new bone formation (NB) were analyzed. Powder based on the material composition was selective melted by a laser beam allowing layer-by-layer production. Pore size and biocompatibility were tested with mesenchymal stem cells (rMSC) and Saos 2 cells that were cultivated on SCs showing better proliferation, without toxicity, than controls. SCs with a 600- to 700-µm pore diameter proved ideal for fast and reliable cellular and vascular supply throughout the interconnecting pore system. Jaw and calvarial critical-size defects (CSD) with diameters of 5 or 16 mm were drilled in rats and either SLM test SCs (pore diameter 600 µm) or the previously removed autologs bone as controls were (re-) implanted. The SC in vivo led to complete bone ingrowth with minimal inflammatory reaction adjacent to and within the CSD as compared with controls. The SC promoted the differentiation of rMSC into osteoblasts, revealing osteoinductive properties. Promising NB ingrowth of the material was also obtained in the animal study. The SC showed complete bony replacement within 30 days in all rats; this ingrowth was significantly superior to that of controls and revealed no signs of significant foreign body reaction. Because of continuous replacement by bone this material composition is ideal for SCs fitting 3D bone defects. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1216-1231, 2017. © 2016 Wiley Periodicals, Inc.

  9. Fully portable blood irradiator

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1980-01-01

    A fully portable blood irradiator was developed using the beta emitter thulium-170 as the radiation source and vitreous carbon as the body of the irradiator, matrix for isotope encapsulation, and blood interface material. These units were placed in exteriorized arteriovenous shunts in goats, sheep, and dogs and the effects on circulating lymphocytes and on skin allograft retention times measured. The present work extends these studies by establishing baseline data for skin graft rejection times in untreated animals

  10. Android Fully Loaded

    Huddleston, Rob

    2012-01-01

    Fully loaded with the latest tricks and tips on your new Android! Android smartphones are so hot, they're soaring past iPhones on the sales charts. And the second edition of this muscular little book is equally impressive--it's packed with tips and tricks for getting the very most out of your latest-generation Android device. Start Facebooking and tweeting with your Android mobile, scan barcodes to get pricing and product reviews, download your favorite TV shows--the book is positively bursting with practical and fun how-tos. Topics run the gamut from using speech recognition, location-based m

  11. Two-stage implant systems.

    Fritz, M E

    1999-06-01

    Since the advent of osseointegration approximately 20 years ago, there has been a great deal of scientific data developed on two-stage integrated implant systems. Although these implants were originally designed primarily for fixed prostheses in the mandibular arch, they have been used in partially dentate patients, in patients needing overdentures, and in single-tooth restorations. In addition, this implant system has been placed in extraction sites, in bone-grafted areas, and in maxillary sinus elevations. Often, the documentation of these procedures has lagged. In addition, most of the reports use survival criteria to describe results, often providing overly optimistic data. It can be said that the literature describes a true adhesion of the epithelium to the implant similar to adhesion to teeth, that two-stage implants appear to have direct contact somewhere between 50% and 70% of the implant surface, that the microbial flora of the two-stage implant system closely resembles that of the natural tooth, and that the microbiology of periodontitis appears to be closely related to peri-implantitis. In evaluations of the data from implant placement in all of the above-noted situations by means of meta-analysis, it appears that there is a strong case that two-stage dental implants are successful, usually showing a confidence interval of over 90%. It also appears that the mandibular implants are more successful than maxillary implants. Studies also show that overdenture therapy is valid, and that single-tooth implants and implants placed in partially dentate mouths have a success rate that is quite good, although not quite as high as in the fully edentulous dentition. It would also appear that the potential causes of failure in the two-stage dental implant systems are peri-implantitis, placement of implants in poor-quality bone, and improper loading of implants. There are now data addressing modifications of the implant surface to alter the percentage of

  12. Contraceptive implants: current perspectives

    Rowlands S

    2014-09-01

    Full Text Available Sam Rowlands,1,2 Stephen Searle3 1Centre of Postgraduate Medical Research and Education, School of Health and Social Care, Bournemouth University, Bournemouth, United Kingdom; 2Dorset HealthCare, Bournemouth, United Kingdom; 3Sexual Health Services, Chesterfield, United KingdomAbstract: Progestin-only contraceptive implants are a highly cost-effective form of long-acting reversible contraception. They are the most effective reversible contraceptives and are of a similar effectiveness to sterilization. Pregnancies are rare in women using this method of contraception, and those that do occur must be fully investigated, with an ultrasound scan of the arm and serum etonogestrel level if the implant cannot be located. There are very few contraindications to use of implants, and they have an excellent safety profile. Both acceptability and continuation with the method are high. Noncontraceptive benefits include improvements in dysmenorrhea, ovulatory pain, and endometriosis. Problematic bleeding is a relatively common adverse effect that must be covered in preinsertion information-giving and supported adequately if it occurs. Recognized training for both insertion and removal should be undertaken. Care needs to be taken at both insertion and removal to avoid neurovascular injury. Implants should always be palpable; if they are not, noninsertion should be assumed until disproven. Etonogestrel implants are now radiopaque, which aids localization. Anticipated difficult removals should be performed by specially trained experts. Keywords: contraceptive, subdermal implant, etonogestrel, levonorgestrel, progestin-only, long-acting reversible contraception

  13. Cochlear Implants

    ... implant, including: • How long a person has been deaf, •The number of surviving auditory nerve fibers, and • ... Implant, Severe Sensoryneurial Hearing Loss Get Involved Professional Development Practice Management ENT Careers Marketplace Privacy Policy Terms ...

  14. Fully electric waste collection

    Anaïs Schaeffer

    2015-01-01

    Since 15 June, Transvoirie, which provides waste collection services throughout French-speaking Switzerland, has been using a fully electric lorry for its collections on the CERN site – a first for the region!   Featuring a motor powered by electric batteries that charge up when the brakes are used, the new lorry that roams the CERN site is as green as can be. And it’s not only the motor that’s electric: its waste compactor and lifting mechanism are also electrically powered*, making it the first 100% electric waste collection vehicle in French-speaking Switzerland. Considering that a total of 15.5 tonnes of household waste and paper/cardboard are collected each week from the Meyrin and Prévessin sites, the benefits for the environment are clear. This improvement comes as part of CERN’s contract with Transvoirie, which stipulates that the firm must propose ways of becoming more environmentally friendly (at no extra cost to CERN). *The was...

  15. Incidence of peri-implant mucositis and peri-implantitis in edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period

    Meijer, Henny J. A.; Raghoebar, Gerry M.; de Waal, Yvonne C. M.; Vissink, Arjan

    2014-01-01

    Objectives: The aim of this sub-analysis of two prospective studies was to assess the incidence of peri-implant mucositis and peri-implantitis in fully edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period. Material and Methods: One hundred and fifty

  16. Multipartite fully nonlocal quantum states

    Almeida, Mafalda L.; Cavalcanti, Daniel; Scarani, Valerio; Acin, Antonio

    2010-01-01

    We present a general method for characterizing the quantum correlations obtained after local measurements on multipartite systems. Sufficient conditions for a quantum system to be fully nonlocal according to a given partition, as well as being (genuinely) multipartite fully nonlocal, are derived. These conditions allow us to identify all completely connected graph states as multipartite fully nonlocal quantum states. Moreover, we show that this feature can also be observed in mixed states: the tensor product of five copies of the Smolin state, a biseparable and bound entangled state, is multipartite fully nonlocal.

  17. Ion implantation

    Johnson, E.

    1986-01-01

    It is the purpose of the present paper to give a review of surface alloy processing by ion implantation. However, rather than covering this vast subject as a whole, the survey is confined to a presentation of the microstructures that can be found in metal surfaces after ion implantation. The presentation is limited to alloys processed by ion implantation proper, that is to processes in which the alloy compositions are altered significantly by direct injection of the implanted ions. The review is introduced by a presentation of the processes taking place during development of the fundamental event in ion implantation - the collision cascade, followed by a summary of the various microstructures which can be formed after ion implantation into metals. This is compared with the variability of microstructures that can be achieved by rapid solidification processing. The microstructures are subsequently discussed in the light of the processes which, as the implantations proceed, take place during and immediately after formation of the individual collision cascades. These collision cascades define the volumes inside which individual ions are slowed down in the implanted targets. They are not only centres for vigorous agitation but also the sources for formation of excess concentrations of point defects, which will influence development of particular microstructures. A final section presents a selection of specific structures which have been observed in different alloy systems. (orig./GSCH)

  18. Carmustine Implant

    ... works by slowing or stopping the growth of cancer cells in your body. ... are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving carmustine implant, call your doctor. Carmustine may harm the fetus.

  19. Cochlear Implants

    ... NIDCD A cochlear implant is a small, complex electronic device that can help to provide a sense ... Hearing Aids Retinitis Pigmentosa - National Eye Institute Telecommunications Relay Services Usher Syndrome Your Baby's Hearing Screening News ...

  20. Implantation, recoil implantation, and sputtering

    Kelly, R.

    1984-01-01

    The implantation and sputtering mechanisms which are relevant to ion bombardment of surfaces are described. These are: collision, thermal, electronic and photon-induced sputtering. 135 refs.; 36 figs.; 9 tabs

  1. Hip Implant Systems

    ... Implants and Prosthetics Metal-on-Metal Hip Implants Hip Implants Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Hip implants are medical devices intended to restore mobility ...

  2. Breast reconstruction - implants

    Breast implants surgery; Mastectomy - breast reconstruction with implants; Breast cancer - breast reconstruction with implants ... harder to find a tumor if your breast cancer comes back. Getting breast implants does not take as long as breast reconstruction ...

  3. Physics of fully ionized regions

    Flower, D.

    1975-01-01

    In this paper the term fully ionised regions is taken to embrace both planetary nebulae and the so-called 'H II' regions referred to as H + regions. Whilst these two types of gaseous nebulae are very different from an evolutionary standpoint, they are physically very similar, being characterised by photoionisation of a low-density plasma by a hot star. (Auth.)

  4. Fully porous 3D printed titanium femoral stem to reduce stress-shielding following total hip arthroplasty.

    Arabnejad, Sajad; Johnston, Burnett; Tanzer, Michael; Pasini, Damiano

    2017-08-01

    Current hip replacement femoral implants are made of fully solid materials which all have stiffness considerably higher than that of bone. This mechanical mismatch can cause significant bone resorption secondary to stress shielding, which can lead to serious complications such as peri-prosthetic fracture during or after revision surgery. In this work, a high strength fully porous material with tunable mechanical properties is introduced for use in hip replacement design. The implant macro geometry is based off of a short stem taper-wedge implant compatible with minimally invasive hip replacement surgery. The implant micro-architecture is fine-tuned to locally mimic bone tissue properties which results in minimum bone resorption secondary to stress shielding. We present a systematic approach for the design of a 3D printed fully porous hip implant that encompasses the whole activity spectrum of implant development, from concept generation, multiscale mechanics of porous materials, material architecture tailoring, to additive manufacturing, and performance assessment via in vitro experiments in composite femurs. We show that the fully porous implant with an optimized material micro-structure can reduce the amount of bone loss secondary to stress shielding by 75% compared to a fully solid implant. This result also agrees with those of the in vitro quasi-physiological experimental model and the corresponding finite element model for both the optimized fully porous and fully solid implant. These studies demonstrate the merit and the potential of tuning material architecture to achieve a substantial reduction of bone resorption secondary to stress shielding. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1774-1783, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  5. Wireless Performance of a Fully Passive Neurorecording Microsystem Embedded in Dispersive Human Head Phantom

    Schwerdt, Helen N.; Chae, Junseok; Miranda, Felix A.

    2012-01-01

    This paper reports the wireless performance of a biocompatible fully passive microsystem implanted in phantom media simulating the dispersive dielectric properties of the human head, for potential application in recording cortical neuropotentials. Fully passive wireless operation is achieved by means of backscattering electromagnetic (EM) waves carrying 3rd order harmonic mixing products (2f(sub 0) plus or minus f(sub m)=4.4-4.9 GHZ) containing targeted neuropotential signals (fm approximately equal to 1-1000 Hz). The microsystem is enclosed in 4 micrometer thick parylene-C for biocompatibility and has a footprint of 4 millimeters x 12 millimeters x 500 micrometers. Preliminary testing of the microsystem implanted in the lossy biological simulating media results in signal-to-noise ratio's (SNR) near 22 (SNR approximately equal to 38 in free space) for millivolt level neuropotentials, demonstrating the potential for fully passive wireless microsystems in implantable medical applications.

  6. Primary prevention of peri-implantitis: managing peri-implant mucositis.

    Jepsen, Søren; Berglundh, Tord; Genco, Robert; Aass, Anne Merete; Demirel, Korkud; Derks, Jan; Figuero, Elena; Giovannoli, Jean Louis; Goldstein, Moshe; Lambert, France; Ortiz-Vigon, Alberto; Polyzois, Ioannis; Salvi, Giovanni E; Schwarz, Frank; Serino, Giovanni; Tomasi, Cristiano; Zitzmann, Nicola U

    2015-04-01

    Over the past decades, the placement of dental implants has become a routine procedure in the oral rehabilitation of fully and partially edentulous patients. However, the number of patients/implants affected by peri-implant diseases is increasing. As there are--in contrast to periodontitis--at present no established and predictable concepts for the treatment of peri-implantitis, primary prevention is of key importance. The management of peri-implant mucositis is considered as a preventive measure for the onset of peri-implantitis. Therefore, the remit of this working group was to assess the prevalence of peri-implant diseases, as well as risks for peri-implant mucositis and to evaluate measures for the management of peri-implant mucositis. Discussions were informed by four systematic reviews on the current epidemiology of peri-implant diseases, on potential risks contributing to the development of peri-implant mucositis, and on the effect of patient and of professionally administered measures to manage peri-implant mucositis. This consensus report is based on the outcomes of these systematic reviews and on the expert opinion of the participants. Key findings included: (i) meta-analysis estimated a weighted mean prevalence for peri-implant mucositis of 43% (CI: 32-54%) and for peri-implantitis of 22% (CI: 14-30%); (ii) bleeding on probing is considered as key clinical measure to distinguish between peri-implant health and disease; (iii) lack of regular supportive therapy in patients with peri-implant mucositis was associated with increased risk for onset of peri-implantitis; (iv) whereas plaque accumulation has been established as aetiological factor, smoking was identified as modifiable patient-related and excess cement as local risk indicator for the development of peri-implant mucositis; (v) patient-administered mechanical plaque control (with manual or powered toothbrushes) has been shown to be an effective preventive measure; (vi) professional intervention

  7. Digital photoelastic analysis applied to implant dentistry

    Ramesh, K.; Hariprasad, M. P.; Bhuvanewari, S.

    2016-12-01

    Development of improved designs of implant systems in dentistry have necessitated the study of stress fields in the implant regions of the mandible/maxilla for better understanding of the biomechanics involved. Photoelasticity has been used for various studies related to dental implants in view of whole field visualization of maximum shear stress in the form of isochromatic contours. The potential of digital photoelasticity has not been fully exploited in the field of implant dentistry. In this paper, the fringe field in the vicinity of the connected implants (All-On-Four® concept) is analyzed using recent advances in digital photoelasticity. Initially, a novel 3-D photoelastic model making procedure, to closely mimic all the anatomical features of the human mandible is proposed. By choosing appropriate orientation of the model with respect to the light path, the essential region of interest were sought to be analysed while keeping the model under live loading conditions. Need for a sophisticated software module to carefully identify the model domain has been brought out. For data extraction, five-step method is used and isochromatics are evaluated by twelve fringe photoelasticity. In addition to the isochromatic fringe field, whole field isoclinic data is also obtained for the first time in implant dentistry, which could throw important information in improving the structural stability of the implant systems. Analysis is carried out for the implant in the molar as well as the incisor region. In addition, the interaction effects of loaded molar implant on the incisor area are also studied.

  8. Short Implants: New Horizon in Implant Dentistry.

    Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-09-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

  9. Axiomatisation of fully probabilistic design

    Kárný, Miroslav; Kroupa, Tomáš

    2012-01-01

    Roč. 186, č. 1 (2012), s. 105-113 ISSN 0020-0255 R&D Projects: GA MŠk(CZ) 2C06001; GA ČR GA102/08/0567 Institutional research plan: CEZ:AV0Z10750506 Keywords : Bayesian decision making * Fully probabilistic design * Kullback–Leibler divergence * Unified decision making Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 3.643, year: 2012 http://library.utia.cas.cz/separaty/2011/AS/karny-0367271.pdf

  10. Physics of fully depleted CCDs

    Holland, S E; Bebek, C J; Kolbe, W F; Lee, J S

    2014-01-01

    In this work we present simple, physics-based models for two effects that have been noted in the fully depleted CCDs that are presently used in the Dark Energy Survey Camera. The first effect is the observation that the point-spread function increases slightly with the signal level. This is explained by considering the effect on charge-carrier diffusion due to the reduction in the magnitude of the channel potential as collected signal charge acts to partially neutralize the fixed charge in the depleted channel. The resulting reduced voltage drop across the carrier drift region decreases the vertical electric field and increases the carrier transit time. The second effect is the observation of low-level, concentric ring patterns seen in uniformly illuminated images. This effect is shown to be most likely due to lateral deflection of charge during the transit of the photo-generated carriers to the potential wells as a result of lateral electric fields. The lateral fields are a result of space charge in the fully depleted substrates arising from resistivity variations inherent to the growth of the high-resistivity silicon used to fabricate the CCDs

  11. Implantation, recoil implantation, and sputtering

    Kelly, R.

    1984-01-01

    Underlying ion-beam modification of surfaces is the more basic subject of particle-surface interaction. The ideas can be grouped into forward and backward features, i.e. those affecting the interior of the target and those leading to particle expulsion. Forward effects include the stopping of the incident particles and the deposition of energy, both governed by integral equations which are easily set up but difficult to solve. Closely related is recoil implantation where emphasis is placed not on the stopping of the incident particles but on their interaction with target atoms with resulting implantation of these atoms. Backward effects, all of which are denoted as sputtering, are in general either of collisional, thermal, electronic, or exfoliational origin. (Auth.)

  12. Fully automated MRI-guided robotics for prostate brachytherapy

    Stoianovici, D.; Vigaru, B.; Petrisor, D.; Muntener, M.; Patriciu, A.; Song, D.

    2008-01-01

    The uncertainties encountered in the deployment of brachytherapy seeds are related to the commonly used ultrasound imager and the basic instrumentation used for the implant. An alternative solution is under development in which a fully automated robot is used to place the seeds according to the dosimetry plan under direct MRI-guidance. Incorporation of MRI-guidance creates potential for physiological and molecular image-guided therapies. Moreover, MRI-guided brachytherapy is also enabling for re-estimating dosimetry during the procedure, because with the MRI the seeds already implanted can be localised. An MRI compatible robot (MrBot) was developed. The robot is designed for transperineal percutaneous prostate interventions, and customised for fully automated MRI-guided brachytherapy. With different end-effectors, the robot applies to other image-guided interventions of the prostate. The robot is constructed of non-magnetic and dielectric materials and is electricity free using pneumatic actuation and optic sensing. A new motor (PneuStep) was purposely developed to set this robot in motion. The robot fits alongside the patient in closed-bore MRI scanners. It is able to stay fully operational during MR imaging without deteriorating the quality of the scan. In vitro, cadaver, and animal tests showed millimetre needle targeting accuracy, and very precise seed placement. The robot tested without any interference up to 7T. The robot is the first fully automated robot to function in MRI scanners. Its first application is MRI-guided seed brachytherapy. It is capable of automated, highly accurate needle placement. Extensive testing is in progress prior to clinical trials. Preliminary results show that the robot may become a useful image-guided intervention instrument. (author)

  13. Dental Implant Surgery

    ... here to find out more. Dental Implant Surgery Dental Implant Surgery Dental implant surgery is, of course, ... to find out more. Wisdom Teeth Management Wisdom Teeth Management An impacted wisdom tooth can damage neighboring ...

  14. Cochlear Implant

    Mehrnaz Karimi

    1992-04-01

    Full Text Available People with profound hearing loss are not able to use some kinds of conventional amplifiers due to the nature of their loss . In these people, hearing sense is stimulated only when the auditory nerve is activated via electrical stimulation. This stimulation is possible through cochlear implant. In fact, for the deaf people who have good mental health and can not use surgical and medical treatment and also can not benefit from air and bone conduction hearing aids, this device is used if they have normal central auditory system. The basic parts of the device included: Microphone, speech processor, transmitter, stimulator and receiver, and electrode array.

  15. Complications after cardiac implantable electronic device implantations

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  16. Restaurant No. 1 fully renovated

    2007-01-01

    The Restaurant No. 1 team. After several months of patience and goodwill on the part of our clients, we are delighted to announce that the major renovation work which began in September 2006 has now been completed. From 21 May 2007 we look forward to welcoming you to a completely renovated restaurant area designed with you in mind. The restaurant team wishes to thank all its clients for their patience and loyalty. Particular attention has been paid in the new design to creating a spacious serving area and providing a wider choice of dishes. The new restaurant area has been designed as an open-plan space to enable you to view all the dishes before making your selection and to move around freely from one food access point to another. It comprises user-friendly areas that fully comply with hygiene standards. From now on you will be able to pick and choose to your heart's content. We invite you to try out wok cooking or some other speciality. Or select a pizza or a plate of pasta with a choice of two sauces fr...

  17. Fully Employing Software Inspections Data

    Shull, Forrest; Feldmann, Raimund L.; Seaman, Carolyn; Regardie, Myrna; Godfrey, Sally

    2009-01-01

    Software inspections provide a proven approach to quality assurance for software products of all kinds, including requirements, design, code, test plans, among others. Common to all inspections is the aim of finding and fixing defects as early as possible, and thereby providing cost savings by minimizing the amount of rework necessary later in the lifecycle. Measurement data, such as the number and type of found defects and the effort spent by the inspection team, provide not only direct feedback about the software product to the project team but are also valuable for process improvement activities. In this paper, we discuss NASA's use of software inspections and the rich set of data that has resulted. In particular, we present results from analysis of inspection data that illustrate the benefits of fully utilizing that data for process improvement at several levels. Examining such data across multiple inspections or projects allows team members to monitor and trigger cross project improvements. Such improvements may focus on the software development processes of the whole organization as well as improvements to the applied inspection process itself.

  18. From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients

    Giorgio Andrea Dolcini

    2016-01-01

    Full Text Available Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT, the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results.

  19. The fully Mobile City Government Project (MCity)

    Scholl, Hans; Fidel, Raya; Mai, Jens Erik

    2006-01-01

    The Fully Mobile City Government Project, also known as MCity, is an interdisciplinary research project on the premises, requirements, and effects of fully mobile, wirelessly connected applications (FWMC). The project will develop an analytical framework for interpreting the interaction and inter......The Fully Mobile City Government Project, also known as MCity, is an interdisciplinary research project on the premises, requirements, and effects of fully mobile, wirelessly connected applications (FWMC). The project will develop an analytical framework for interpreting the interaction...

  20. Individual titanium zygomatic implant

    Nekhoroshev, M. V.; Ryabov, K. N.; Avdeev, E. V.

    2018-03-01

    Custom individual implants for the reconstruction of craniofacial defects have gained importance due to better qualitative characteristics over their generic counterparts – plates, which should be bent according to patient needs. The Additive Manufacturing of individual implants allows reducing cost and improving quality of implants. In this paper, the authors describe design of zygomatic implant models based on computed tomography (CT) data. The fabrication of the implants will be carried out with 3D printing by selective laser melting machine SLM 280HL.

  1. Implantable Medical Devices

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Implantable Medical Devices Updated:Sep 16,2016 For Rhythm Control ... a Heart Attack Introduction Medications Surgical Procedures Implantable Medical Devices • Life After a Heart Attack • Heart Attack ...

  2. Intercavitary implants dosage calculation

    Rehder, B.P.

    The use of spacial geometry peculiar to each treatment for the attainment of intercavitary and intersticial implants dosage calculation is presented. The study is made in patients with intercavitary implants by applying a modified Manchester technique [pt

  3. Implantable electronic medical devices

    Fitzpatrick, Dennis

    2014-01-01

    Implantable Electronic Medical Devices provides a thorough review of the application of implantable devices, illustrating the techniques currently being used together with overviews of the latest commercially available medical devices. This book provides an overview of the design of medical devices and is a reference on existing medical devices. The book groups devices with similar functionality into distinct chapters, looking at the latest design ideas and techniques in each area, including retinal implants, glucose biosensors, cochlear implants, pacemakers, electrical stimulation t

  4. An in vivo assessment of the effects of using different implant abutment occluding materials on implant microleakage and the peri-implant microbiome

    Rubino, Caroline

    Microleakage may be a factor in the progression of peri-implant pathology. Microleakage in implant dentistry refers to the passage of bacteria, fluids, molecules or ions between the abutment-implant interface to and from the surrounding periodontal tissues. This creates a zone of inflammation and reservoir of bacteria at the implant-abutment interface. Bone loss typically occurs within the first year of abutment connection and then stabilizes. It has not yet been definitively proven that the occurrence of microleakage cannot contribute to future bone loss or impede the treatment of peri-implant disease. Therefore, strategies to reduce or eliminate microleakage are sought out. Recent evidence demonstrates that the type of implant abutment channel occluding material can affect the amount of microleakage in an in vitro study environment. Thus, we hypothesize that different abutment screw channel occluding materials will affect the amount of observed microleakage, vis-a-vis the correlation between the microflora found on the abutment screw channel occluding material those found in the peri-implant sulcus. Additional objectives include confirming the presence of microleakage in vivo and assessing any impact that different abutment screw channel occluding materials may have on the peri-implant microbiome. Finally, the present study provides an opportunity to further characterize the peri-implant microbiome. Eight fully edentulous patients restored with at dental implants supporting screw-retained fixed hybrid prostheses were included in the study. At the initial appointment (T1), the prostheses were removed and the implants and prostheses were cleaned. The prostheses were then inserted with polytetrafluoroethylene tape (PTFE, TeflonRTM), cotton, polyvinyl siloxane (PVS), or synthetic foam as the implant abutment channel occluding material and sealed over with composite resin. About six months later (T2), the prostheses were removed and the materials collected. Paper

  5. Clinical outcome of critically ill, not fully recompensated, patients undergoing MitraClip therapy

    Rudolph, Volker; Huntgeburth, Michael; von Bardeleben, Ralph Stephan

    2014-01-01

    AIMS: As periprocedural risk is low, MitraClip implantation is often performed in critically ill, not fully recompensated patients, who are in NYHA functional class IV at the time of the procedure, to accelerate convalescence. We herein sought to evaluate the procedural and 30-day outcome.......3%. CONCLUSION: MitraClip therapy is feasible and safe even in critically ill, not fully recompensated patients and leads to symptomatic improvement in over two-thirds of these patients; however, it is associated with an elevated 30-day mortality....

  6. A fully organic retinal prosthesis restores vision in a rat model of degenerative blindness

    Maya-Vetencourt, José Fernando; Ghezzi, Diego; Antognazza, Maria Rosa; Colombo, Elisabetta; Mete, Maurizio; Feyen, Paul; Desii, Andrea; Buschiazzo, Ambra; di Paolo, Mattia; di Marco, Stefano; Ticconi, Flavia; Emionite, Laura; Shmal, Dmytro; Marini, Cecilia; Donelli, Ilaria; Freddi, Giuliano; Maccarone, Rita; Bisti, Silvia; Sambuceti, Gianmario; Pertile, Grazia; Lanzani, Guglielmo; Benfenati, Fabio

    2017-06-01

    The degeneration of photoreceptors in the retina is one of the major causes of adult blindness in humans. Unfortunately, no effective clinical treatments exist for the majority of retinal degenerative disorders. Here we report on the fabrication and functional validation of a fully organic prosthesis for long-term in vivo subretinal implantation in the eye of Royal College of Surgeons rats, a widely recognized model of retinitis pigmentosa. Electrophysiological and behavioural analyses reveal a prosthesis-dependent recovery of light sensitivity and visual acuity that persists up to 6-10 months after surgery. The rescue of the visual function is accompanied by an increase in the basal metabolic activity of the primary visual cortex, as demonstrated by positron emission tomography imaging. Our results highlight the possibility of developing a new generation of fully organic, highly biocompatible and functionally autonomous photovoltaic prostheses for subretinal implants to treat degenerative blindness.

  7. Preliminary Thermal Characterization of a Fully-Passive Wireless Backscattering Neuro-Recording Microsystem

    Schwerdt, H. N.; Xu, W.; Shekhar, S.; Chae, J.; Miranda, F. A.

    2011-01-01

    We present analytical and experimental thermal characteristics of a battery-less, fully-passive wireless backscattering microsystem for recording of neuropotentials. A major challenge for cortically implantable microsystems involves minimizing the heat dissipated by on-chip circuitry, which can lead to permanent brain damage. Therefore, knowledge of temperature changes induced by implantable microsystems while in operation is of utmost importance. In this work, a discrete diode appended to the neuro-recording microsystem has been used to indirectly monitor the aforesaid temperature changes. Using this technique, the maximum temperature rise measured for the microsystem while in operation was 0.15 +/- 0.1 C, which is significantly less than current safety guidelines. Specific absorption ratio (SAR) due to the microsystem was also computed to further demonstrate fully-passive functionality of the neuro-recording microsystem.

  8. Trends in cochlear implants.

    Zeng, Fan-Gang

    2004-01-01

    More than 60,000 people worldwide use cochlear implants as a means to restore functional hearing. Although individual performance variability is still high, an average implant user can talk on the phone in a quiet environment. Cochlear-implant research has also matured as a field, as evidenced by the exponential growth in both the patient population and scientific publication. The present report examines current issues related to audiologic, clinical, engineering, anatomic, and physiologic aspects of cochlear implants, focusing on their psychophysical, speech, music, and cognitive performance. This report also forecasts clinical and research trends related to presurgical evaluation, fitting protocols, signal processing, and postsurgical rehabilitation in cochlear implants. Finally, a future landscape in amplification is presented that requires a unique, yet complementary, contribution from hearing aids, middle ear implants, and cochlear implants to achieve a total solution to the entire spectrum of hearing loss treatment and management.

  9. Benefits and Risks of Cochlear Implants

    ... and Medical Procedures Implants and Prosthetics Cochlear Implants Benefits and Risks of Cochlear Implants Share Tweet Linkedin ... the Use of Cochlear Implants What are the Benefits of Cochlear Implants? For people with implants: Hearing ...

  10. Tolerance, immunocompetence, and secondary disease in fully allogeneic radiation chimeras

    Rayfield, L.S.; Brent, L.

    1983-01-01

    The aim of this study was to ascertain the extent to which secondary disease and mortality in fully allogeneic chimeras (C57BL leads to CBA) is caused (if at all) by a delayed graft-versus-host reaction. Adult CBA males were thymectomized, irradiated, and reconstituted with T-lymphocyte-depleted C57BL or CBA bone marrow cells (BMC), followed three weeks after irradiation by implantation under the kidney capsule of thymic lobes from C57BL or CBA fetal or adult donors. These mice were observed for the development of secondary disease for periods in excess of 250 days, and they were examined at 5 weeks or 4 months for T lymphocyte reactivity and tolerance to alloantigens, using the cell-mediated lympholysis assay (CML). The following results were obtained. First, removal of T lymphocytes with anti-Thy 1 antibody and complement from allogeneic bone marrow did not prevent wasting and eventual death, although it prolonged the lifespan of mice substantially. Second, T lymphocytes generated from bone marrow-derived precursor cells became tolerant of the histocompatibility antigens of the thymus donor strain but remained normally reactive to third-party antigens. Third, allogeneic radiation chimeras did not survive as well as animals reconstituted with syngeneic cells, even when they were demonstrably tolerant in CML. Fourth, C57BL BMC maturing in a CBA host equipped with a C57BL thymus graft did not become tolerant of host antigens, indicating that extra-thymic tolerance does not occur in fully allogeneic--as opposed to semiallogeneic--chimeras. It is argued that the function of B lymphocytes and/or accessory cells is impaired in fully allogeneic radiation chimeras, and that the mortality observed was directly related to the resulting immunodeficiency. The relevance of the results described in this paper to clinical bone marrow transplantation is discussed

  11. Phacoemulsification and implantation of an accommodating IOL after PRK.

    Aslanides, loannis M; Plainis, Sotiris; Kumar, Vinod; Ginis, Harilaos

    2006-01-01

    To present a case of phacoemulsification and implantation of an accommodating intraocular lens (IOL) in a patient with cataract formation after previous refractive surgery. A 50-year-old man, who initially had photorefractive keratectomy to correct moderate myopia, developed a cataract in one eye. He subsequently underwent phacoemulsification and implantation of a 1CU accommodating IOL, as he wished to remain spectacle independent. The patient's distance vision was fully restored. However, accommodative function, which was assessed using subjective and novice objective techniques, was only partially restored. Although the accommodating IOL fully restored the patient's distance vision, accommodative function was only partially restored.

  12. Optical effects of ion implantation

    Townsend, P.D.

    1987-01-01

    The review concerns the effects of ion implantation that specifically relate to the optical properties of insulators. Topics which are reviewed include: ion implantation, ion range and damage distributions, colour centre production by ion implantation, high dose ion implantation, and applications for integrated optics. Numerous examples are presented of both diagnostic and industrial examples of ion implantation effects in insulators. (U.K.)

  13. Ion implantation in semiconductors

    Gusev, V.; Gusevova, M.

    1980-01-01

    The historical development is described of the method of ion implantation, the physical research of the method, its technological solution and practical uses. The method is universally applicable, allows the implantation of arbitrary atoms to an arbitrary material, ensures high purity of the doping element. It is linked with sample processing at low temperatures. In implantation it is possible to independently change the dose and energy of the ions thereby affecting the spatial distribution of the ions. (M.S.)

  14. Ion implantation in semiconductors

    Gusev, V; Gusevova, M

    1980-06-01

    The historical development of the method of ion implantation, the physical research of the method, its technological solution and practical uses is described. The method is universally applicable, allows the implantation of arbitrary atoms to an arbitrary material and ensures high purity of the doping element. It is linked with sample processing at low temperatures. In implantation it is possible to independently change the dose and energy of the ions thereby affecting the spatial distribution of the ions.

  15. Trends in Cochlear Implants

    Zeng, Fan-Gang

    2004-01-01

    More than 60,000 people worldwide use cochlear implants as a means to restore functional hearing. Although individual performance variability is still high, an average implant user can talk on the phone in a quiet environment. Cochlear-implant research has also matured as a field, as evidenced by the exponential growth in both the patient population and scientific publication. The present report examines current issues related to audiologic, clinical, engineering, anatomic, and physiologic as...

  16. Dental Implants in an Aged Population: Evaluation of Periodontal Health, Bone Loss, Implant Survival, and Quality of Life.

    Becker, William; Hujoel, Philippe; Becker, Burton E; Wohrle, Peter

    2016-06-01

    To evaluate aged partially and fully edentulous patients who received dental implants and were maintained over time. Further, to determine how the partially and edentulous ageing populations (65 and above) with dental implants maintain bone levels, proper oral hygiene, and perceive benefits of dental implants. Since 1995, patients receiving dental implants have been prospectively entered into an Access-based computerized program (Triton Tacking System). Patient demographics (age, sex), bone quality, quantity, implant location, and type of surgery have been continuously entered into the database. The database was queried for patients receiving implants (first stage) between 66 and 93 years of age. Thirty-one patients were within this age group. Twenty-five patients returned to the clinic for periodontal and dental implant evaluation. The Periodontal Index was used to evaluate selected teeth in terms of probing depth, bleeding on probing, plaque accumulation, and mobility. Using NIH Image J, radiographs taken at second stage and last examination were measured for changes in interproximal bone levels. Once identified, each patient anomalously filled out an abbreviated quality of health life form. Due to small sample size, descriptive statistics were used to compare clinical findings. Fifteen males ranging from 78 to 84 (mean age 84 years) years and 16 females from 66 to 93 (mean age 83 years) (age range 66-93) were contacted by phone or mail and asked to return to our office for a re-examination. For this group, the first dental implants were placed in 1996 (n = initial two implants) and continuously recorded through 2013 (n = last seven implants). Thirty-one patients received a total of 84 implants. Two patients were edentulous, and the remaining were partially edentulous. Four implants were lost. Between implant placement and 6- to 7-year interval, 13 patients with 40 implants had a cumulative survival rate of 94.6%. Of the original group (n = 33), three

  17. Ion implantation technology

    Downey, DF; Jones, KS; Ryding, G

    1993-01-01

    Ion implantation technology has made a major contribution to the dramatic advances in integrated circuit technology since the early 1970's. The ever-present need for accurate models in ion implanted species will become absolutely vital in the future due to shrinking feature sizes. Successful wide application of ion implantation, as well as exploitation of newly identified opportunities, will require the development of comprehensive implant models. The 141 papers (including 24 invited papers) in this volume address the most recent developments in this field. New structures and possible approach

  18. High energy ion implantation

    Ziegler, J.F.

    1985-01-01

    High energy ion implantation offers the oppertunity for unique structures in semiconductor processing. The unusual physical properties of such implantations are discussed as well as the special problems in masking and damage annealing. A review is made of proposed circuit structures which involve deep implantation. Examples are: deep buried bipolar collectors fabricated without epitaxy, barrier layers to reduce FET memory sensitivity to soft-fails, CMOS isolation well structures, MeV implantation for customization and correction of completed circuits, and graded reach-throughs to deep active device components. (orig.)

  19. [Silastic implant and synovitis].

    Sennwald, G

    1989-07-22

    The silastic implant based on siloxane polymere induces granulomatous synovitis in certain predisposed individuals, a reaction which may continue even after removal of the implant. This is also true of a prosthesis of the trapezium in two of our patients, though to a lesser degree. This is probably the reason why the problem has not yet been widely recognized. The hypothesis is put forward that an enzymatic predisposition may allow chemical degradation of the fragmented silastic implant into a toxic component responsible for the pathologic condition. The slow progression of the lesions is a challenge for the future and puts in question the further use of silastic implants.

  20. Cochlear implant magnet retrofit.

    Cohen, N L; Breda, S D; Hoffman, R A

    1988-06-01

    An implantable magnet is now available for patients who have received the standard Nucleus 22-channel cochlear implant and who are not able to wear the headband satisfactorily. This magnet is attached in piggy-back fashion to the previously implanted receiver/stimulator by means of a brief operation under local anesthesia. Two patients have received this magnet retrofit, and are now wearing the headset with greater comfort and satisfaction. It is felt that the availability of this magnet will increase patient compliance in regard to hours of implant usage.

  1. Fully Depleted Charge-Coupled Devices

    Holland, Stephen E.

    2006-01-01

    We have developed fully depleted, back-illuminated CCDs that build upon earlier research and development efforts directed towards technology development of silicon-strip detectors used in high-energy-physics experiments. The CCDs are fabricated on the same type of high-resistivity, float-zone-refined silicon that is used for strip detectors. The use of high-resistivity substrates allows for thick depletion regions, on the order of 200-300 um, with corresponding high detection efficiency for near-infrared and soft x-ray photons. We compare the fully depleted CCD to the p-i-n diode upon which it is based, and describe the use of fully depleted CCDs in astronomical and x-ray imaging applications

  2. CMOS current controlled fully balanced current conveyor

    Wang Chunhua; Zhang Qiujing; Liu Haiguang

    2009-01-01

    This paper presents a current controlled fully balanced second-generation current conveyor circuit (CF-BCCII). The proposed circuit has the traits of fully balanced architecture, and its X-Y terminals are current controllable. Based on the CFBCCII, two biquadratic universal filters are also proposed as its applications. The CFBCCII circuits and the two filters were fabricated with chartered 0.35-μm CMOS technology; with ±1.65 V power supply voltage, the total power consumption of the CFBCCII circuit is 3.6 mW. Comparisons between measured and HSpice simulation results are also given.

  3. Fully exponentially correlated wavefunctions for small atoms

    Harris, Frank E. [Department of Physics, University of Utah, Salt Lake City, UT 84112 and Quantum Theory Project, University of Florida, P.O. Box 118435, Gainesville, FL 32611 (United States)

    2015-01-22

    Fully exponentially correlated atomic wavefunctions are constructed from exponentials in all the interparticle coordinates, in contrast to correlated wavefunctions of the Hylleraas form, in which only the electron-nuclear distances occur exponentially, with electron-electron distances entering only as integer powers. The full exponential correlation causes many-configuration wavefunctions to converge with expansion length more rapidly than either orbital formulations or correlated wavefunctions of the Hylleraas type. The present contribution surveys the effectiveness of fully exponentially correlated functions for the three-body system (the He isoelectronic series) and reports their application to a four-body system (the Li atom)

  4. A 96-channel, 500 ps resolution TDC board for the BaBar experiment at SLAC

    Minutoli, S

    2000-01-01

    A TDC board has been designed and built to complete the readout of the Instrumented Flux Return of the BABAR experiment at the Stanford Linear Accelerator Center. The board has 96 input channels and makes use of 3 general purpose TDC chips designed at CERN, with time resolution up to 500 ps and configurable via a Test Access Port (IEEE standard 1149). Data are stored before readout in a multievent buffer. Communication with BABAR DAQ system is realized through 3 serial lines on the backplane connector. All the logic, including internal registers and the interfaces with the BABAR protocol and the TAP controller, is implemented in two fast FPGAs. The board is designed to work at 59.5 MHz clock frequency. (7 refs).

  5. A 96 channel receiver for the ILCTA LLRF system at Fermilab

    Mavric, Uros; Chase, Brian; Branlard, Julien; Cullerton, Ed; Klepec, Dan; Fermilab

    2007-01-01

    The present configuration of an ILC main LINAC RF station has 26 nine cell cavities driven from one klystron. With the addition of waveguide power coupler monitors, 96 RF signals will be down-converted and processed. A down-converter chassis is being developed that contains 12 eight channel analog modules and a single upconverter module. This chassis will first be deployed for testing a cryomodule composed of eight cavities located at New Muon Laboratory (NML) - Fermilab. Critical parts of the design for LLRF applications are identified and a detailed description of the circuit with various characteristic measurements is presented. The board is composed of an input band-pass filter centered at 1.3GHz, followed by a mixer, which down-converts the cavity probe signal to a proposed 13 MHz intermediate frequency. Cables with 8 channels per connector and good isolation between channels are being used to interconnect each down-converter module with a digital board. As mixers, amplifiers and power splitters are the most sensitive parts for noise, nonlinearities and crosstalk issues, special attention is given to these parts in the design of the LO port multiplication and distribution

  6. Maxillary implant-retained partial overdenture with Dolder bar attachment: a clinical report.

    Kim, Hyeongil; Buhite, Robert J; Monaco, Edward A

    2015-03-01

    This article describes a technique for maintaining a maxillary Kennedy III partial removable dental prosthesis design in a patient who had non-restorable failing abutments by replacing the abutments with dental implants. Two implants were placed immediately after extraction of the abutment teeth in the anterior maxilla. After the implants were fully integrated, a Dolder bar attachment was fitted onto the implants. A new maxillary partial removable dental prosthesis was fabricated using the implants and the remaining natural teeth as abutments to restore function and esthetics. With the aid of dental implants, this Kennedy III maxillary removable dental prosthesis design could provide additional retention and support by promoting cross-arch stability and tissue, implant and tooth support. The patient's satisfaction was significantly increased.

  7. Protocol for Bone Augmentation with Simultaneous Early Implant Placement: A Retrospective Multicenter Clinical Study

    Peter Fairbairn

    2015-01-01

    Full Text Available Purpose. To present a novel protocol for alveolar bone regeneration in parallel to early implant placement. Methods. 497 patients in need of extraction and early implant placement with simultaneous bone augmentation were treated in a period of 10 years. In all patients the same specific method was followed and grafting was performed utilizing in situ hardening fully resorbable alloplastic grafting materials consisting of β-tricalcium phosphate and calcium sulfate. The protocol involved atraumatic extraction, implant placement after 4 weeks with simultaneous bone augmentation, and loading of the implant 12 weeks after placement and grafting. Follow-up periods ranged from 6 months to 10 years (mean of 4 years. Results. A total of 601 postextraction sites were rehabilitated in 497 patients utilizing the novel protocol. Three implants failed before loading and three implants failed one year after loading, leaving an overall survival rate of 99.0%. Conclusions. This standardized protocol allows successful long-term functional results regarding alveolar bone regeneration and implant rehabilitation. The concept of placing the implant 4 weeks after extraction, augmenting the bone around the implant utilizing fully resorbable, biomechanically stable, alloplastic materials, and loading the implant at 12 weeks seems to offer advantages when compared with traditional treatment modalities.

  8. Quantum Fully Homomorphic Encryption with Verification

    Alagic, Gorjan; Dulek, Yfke; Schaffner, Christian

    2017-01-01

    Fully-homomorphic encryption (FHE) enables computation on encrypted data while maintaining secrecy. Recent research has shown that such schemes exist even for quantum computation. Given the numerous applications of classical FHE (zero-knowledge proofs, secure two-party computation, obfuscation, e...

  9. Fully conditional specification in multivariate imputation

    van Buuren, S.; Brand, J. P.L.; Groothuis-Oudshoorn, C. G.M.; Rubin, D. B.

    2006-01-01

    The use of the Gibbs sampler with fully conditionally specified models, where the distribution of each variable given the other variables is the starting point, has become a popular method to create imputations in incomplete multivariate data. The theoretical weakness of this approach is that the

  10. Equipment for fully automatic radiographic pipe inspection

    Basler, G.; Sperl, H.; Weinschenk, K.

    1977-01-01

    The patent describes a device for fully automatic radiographic testing of large pipes with longitudinal welds. Furthermore the invention enables automatic marking of films in radiographic inspection with regard to a ticketing of the test piece and of that part of it where testing took place. (RW) [de

  11. Faster Fully-Dynamic minimum spanning forest

    Holm, Jacob; Rotenberg, Eva; Wulff-Nilsen, Christian

    2015-01-01

    We give a new data structure for the fully-dynamic minimum spanning forest problem in simple graphs. Edge updates are supported in O(log4 n/log logn) expected amortized time per operation, improving the O(log4 n) amortized bound of Holm et al. (STOC’98, JACM’01).We also provide a deterministic data...

  12. Percutaneous and skeletal biocarbon implants

    Mooney, V.

    1977-01-01

    Review of carbon implants developed by NASA discussed four different types of implants and subsequent improvements. Improvements could be of specific interest to rehabilitation centers and similar organizations.

  13. Degradable Implantate: Entwicklungsbeispiele

    Ruffieux, Kurt; Wintermantel, Erich

    Resorbierbare Implantate werden seit mehreren Jahrzehnten in der Implantologie eingesetzt. Bekannt wurden diese Biomaterialien mit dem Aufkommen von sich selbst auflösenden Nahtfäden auf der Basis von synthetisch hergestellten Polylactiden und Polyglycoliden in den 70er Jahren. In einem nächsten Schritt wurden Implantate wie Platten und Schrauben zur Gewebefixation aus den gleichen Biomaterialien hergestellt.

  14. Risks of Breast Implants

    ... have a risk of developing a type of cancer called breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) in the breast tissue surrounding the implant. BIA-ALCL is not breast cancer. Women diagnosed with BIA-ALCL may need to ...

  15. Ion implantation of metals

    Dearnaley, G.

    1976-01-01

    In this part of the paper descriptions are given of the effects of ion implantation on (a) friction and wear in metals; and (b) corrosion of metals. In the study of corrosion, ion implantation can be used either to introduce a constituent that is known to convey corrosion resistance, or more generally to examine the parameters which control corrosion. (U.K.)

  16. Ion implantation into diamond

    Sato, Susumu

    1994-01-01

    The graphitization and the change to amorphous state of diamond surface layer by ion implantation and its characteristics are reported. In the diamond surface, into which more than 10 16 ions/cm 2 was implanted, the diamond crystals are broken, and the structure changes to other carbon structure such as amorphous state or graphite. Accompanying this change of structure, the electric conductivity of the implanted layer shows two discontinuous values due to high resistance and low resistance. This control of structure can be done by the temperature of the base during the ion implantation into diamond. Also it is referred to that by the base temperature during implantation, the mutual change of the structure between amorphous state and graphite can be controlled. The change of the electric resistance and the optical characteristics by the ion implantation into diamond surface, the structural analysis by Raman spectroscopy, and the control of the structure of the implanted layer by the base temperature during implantation are reported. (K.I.)

  17. Number of implants for mandibular implant overdentures: a systematic review

    Lee, Jeong-Yol; Kim, Ha-Young; Bryant, S. Ross

    2012-01-01

    PURPOSE The aim of this systematic review is to address treatment outcomes of Mandibular implant overdentures relative to implant survival rate, maintenance and complications, and patient satisfaction. MATERIALS AND METHODS A systematic literature search was conducted by a PubMed search strategy and hand-searching of relevant journals from included studies. Randomized Clinical Trials (RCT) and comparative clinical trial studies on mandibular implant overdentures until August, 2010 were selected. Eleven studies from 1098 studies were finally selected and data were analyzed relative to number of implants. RESULTS Six studies presented the data of the implant survival rate which ranged from 95% to 100% for 2 and 4 implant group and from 81.8% to 96.1% for 1 and 2 implant group. One study, which statistically compared implant survival rate showed no significant differences relative to the number of implants. The most common type of prosthetic maintenance and complications were replacement or reattaching of loose clips for 2 and 4 implant group, and denture repair due to the fracture around an implant for 1 and 2 implant groups. Most studies showed no significant differences in the rate of prosthetic maintenance and complication, and patient satisfaction regardless the number of implants. CONCLUSION The implant survival rate of mandibular overdentures is high regardless of the number of implants. Denture maintenance is likely not inflenced substantially by the number of implants and patient satisfaction is typically high again regardless os the number of implants. PMID:23236572

  18. Clinical and microbiological characteristics of peri-implantitis cases: a retrospective multicentre study.

    Charalampakis, G; Leonhardt, Å; Rabe, P; Dahlén, G

    2012-09-01

    The aim of this study was to follow patient cases retrospectively in a longitudinal manner from the time of implant placement to the time they were diagnosed with peri-implant disease, and to identify associated clinical and microbiological features of peri-implant disease. A total of 281 patient cases were chosen from the archives of the Oral Microbiological Diagnostic Laboratory, Gothenburg, Sweden, based on bacterial samples taken from diseased implants. A form was designed and filled in separately for each case including data on patient, implant and disease profile. Most cases were severe peri-implantitis cases (91.4%). In 41.3% of the patients, peri-implantitis was developed early, already after having implants in function less than 4 years. The type of implant surface was significantly associated with the time in years implants were in function, before disease was developed (P < 0.05). The microbiological results by both culture and checkerboard analysis, although failed to fully correspond to the severity of the disease in terms of magnitude, proved to show that peri-implantitis is a polymicrobial anaerobic infection with increased number of AGNB (aerobic Gram-negative bacilli) in 18.6% of the patients. Peri-implantitis is a biological complication of implants in function that poses a threat to their long-term survival. It may develop earlier around implants with rough surfaces and it may represent a true infection. Microbiological sampling methods should be improved and uniformed so as to fully unveil the microbiological profile of the disease. © 2011 John Wiley & Sons A/S.

  19. Ion implantation into iron

    Iwaki, Masaya

    1978-01-01

    The distribution of implanted ions in iron, the friction characteristics and the corrosion of iron were studied. The distribution of Ni or Cr ions implanted into mild steel was measured. The accelerated voltage was 150 keV, and the beam current density was about 2 microampere/cm 2 . The measurement was made with an ion microanalyzer. The measured distribution was compared with that of LSS theory. Deep invasion of Ni was seen in the measured distribution. The distribution of Cr ions was different from the distribution calculated by the LSS theory. The relative friction coefficient of mild steel varied according to the dose of implanted Cu or N ions, and to the accelerating voltage. Formation of compound metals on the surfaces of metals by ion-implantation was investigated for the purpose to prevent the corrosion of metals. The resistance of mild steel in which Ni ions were implanted was larger than that of mild steel without any treatment. (Kato, T.)

  20. 76 FR 36176 - Fully Developed Claim (Fully Developed Claims-Applications for Compensation, Pension, DIC, Death...

    2011-06-21

    ... DEPARTMENT OF VETERANS AFFAIRS [OMB Control No. 2900-0747] Fully Developed Claim (Fully Developed Claims--Applications for Compensation, Pension, DIC, Death Pension, and/or Accrued Benefits); Correction AGENCY: Veterans Benefits Administration, Department of Veterans Affairs. ACTION: Notice; correction...

  1. A fully implantable telemetry system for the long-term measurement of habitual bone strain

    de Jong, W. C.; Koolstra, J. H.; van Ruijven, L. J.; Korfage, J. A. M.; Langenbach, G. E. J.

    2010-01-01

    Long-term in-vivo recordings of habitual bone strain in freely moving animals are needed to better understand the everyday mechanical loading environment responsible for bone-tissue maintenance. However, wireless methods to make such recordings are scarce. We report on the successful customisation

  2. Influence of Palatal Coverage and Implant Distribution on Implant Strain in Maxillary Implant Overdentures.

    Takahashi, Toshihito; Gonda, Tomoya; Mizuno, Yoko; Fujinami, Yozo; Maeda, Yoshinobu

    2016-01-01

    Maxillary implant overdentures are often used in clinical practice. However, there is no agreement or established guidelines regarding prosthetic design or optimal implant placement configuration. The purpose of this study was to examine the influence of palatal coverage and implant number and distribution in relation to impact strain under maxillary implant overdentures. A maxillary edentulous model with implants and experimental overdentures with and without palatal coverage was fabricated. Four strain gauges were attached to each implant, and they were positioned in the anterior, premolar, and molar areas. A vertical occlusal load of 98 N was applied through a mandibular complete denture, and the implant strains were compared using one-way analysis of variance (P = .05). The palatolabial strain was much higher on anterior implants than on other implants in both denture types. Although there was no significant difference between the strain under dentures with and without palatal coverage, palateless dentures tended to result in higher implant strain than dentures with palatal coverage. Dentures supported by only two implants registered higher strain than those supported by four or six implants. Implants under palateless dentures registered higher strain than those under dentures with palatal coverage. Anterior implants exhibited higher palatolabial strain than other implants regardless of palatal coverage and implant configuration; it is therefore recommended that maxillary implant overdentures should be supported by six implants with support extending to the distal end of the arch.

  3. Approaches to USJ Formation Beyond Molecular Implantation

    Hatem, C.; Renau, A.; Godet, L.; Kontos, A.; Papasouliotis, G.; England, J.; Arevalo, E.

    2008-01-01

    As junction depth requirements approach sub 10 nm and the sensitivity to residual implant damage continues to increase, the capability to produce abrupt, shallow profiles while maintaining low residual damage becomes a difficult challenge. Implantation induced amorphization has been widely applied to reduce channeling tails of implanted dopant profiles for integrated circuit manufacturing. This has been required to meet aggressive junction depth targets. The problem, however, is that pre-amorphization creates high defect densities that remain near the former amorphous-crystalline interface post anneal. These end of range (EOR) defects become of greater concern as the industry begins to move towards millisecond anneal technologies. Millisecond anneal, while capable of close to diffusionless activation and abrupt junctions, has caused concern for its inability to fully repair these EOR defects. There has been a recent focus on removing traditional PAI through molecular implantation with limited success. Towards this end we have investigated alternative techniques to reduce EOR damage while maintaining the junction depth, sheet resistance and abruptness. Here we describe the results of two of these techniques. The subsequent reduction in EOR through the use of each process and the resultant Rs, junction depth and abruptness are detailed.

  4. Design and manufacture of customized dental implants by using reverse engineering and selective laser melting technology.

    Chen, Jianyu; Zhang, Zhiguang; Chen, Xianshuai; Zhang, Chunyu; Zhang, Gong; Xu, Zhewu

    2014-11-01

    Recently a new therapeutic concept of patient-specific implant dentistry has been advanced based on computer-aided design/computer-aided manufacturing technology. However, a comprehensive study of the design and 3-dimensional (3D) printing of the customized implants, their mechanical properties, and their biomechanical behavior is lacking. The purpose of this study was to evaluate the mechanical and biomechanical performance of a novel custom-made dental implant fabricated by the selective laser melting technique with simulation and in vitro experimental studies. Two types of customized implants were designed by using reverse engineering: a root-analog implant and a root-analog threaded implant. The titanium implants were printed layer by layer with the selective laser melting technique. The relative density, surface roughness, tensile properties, bend strength, and dimensional accuracy of the specimens were evaluated. Nonlinear and linear finite element analysis and experimental studies were used to investigate the stress distribution, micromotion, and primary stability of the implants. Selective laser melting 3D printing technology was able to reproduce the customized implant designs and produce high density and strength and adequate dimensional accuracy. Better stress distribution and lower maximum micromotions were observed for the root-analog threaded implant model than for the root-analog implant model. In the experimental tests, the implant stability quotient and pull-out strength of the 2 types of implants indicated that better primary stability can be obtained with a root-analog threaded implant design. Selective laser melting proved to be an efficient means of printing fully dense customized implants with high strength and sufficient dimensional accuracy. Adding the threaded characteristic to the customized root-analog threaded implant design maintained the approximate geometry of the natural root and exhibited better stress distribution and

  5. Simultaneous Bilateral Cochlear Implantation for a 6-Month Child with a History of Meningitis

    Kh. M. Diab

    2015-01-01

    Full Text Available The article presents the first case of simultaneous bilateral cochlear implantation for a 6-month child with IV degree sensorineural hearing loss after meningocephalitis in Russia. Despite partial ossification of the cochlear basal turns, the early timing of implantation allowed to fully implant active electrodes to both ears. The simultaneous bilateral cochlear implantation in young children, who had meningitis, is a minimally invasive and highly efficient procedure with good long-term results of oral-aural after-care.

  6. Rainwater drained through fully filled pipes

    Kuhn, B; Koestel, P

    1989-02-01

    The conventional rainwater drainage system according to DIN 1986 always seems to be a point of problemacy in the building services as far as the occupancy of installation shafts and ducts is at stake. The excavation work and the necessary gravity lines are considered to be expensive. The consideration of the necessary slope complicates the installation additionally. Basing on those considerations, the raindraining system with fully filled pipes has been developed. DIN 1986, edition June 1988, part 1, point 6.1.1 allows to install rainwater pipes operated as planned, fully filled without slope. An enterprise specialised in building services investigated all system laws because only by a hydraulically exact balance, the function of the rainwater drainage system operated by negative and positive pressure can be insured. The results of those investigations are integrated in a computer program developed for this purpose.

  7. Developments towards a fully automated AMS system

    Steier, P.; Puchegger, S.; Golser, R.; Kutschera, W.; Priller, A.; Rom, W.; Wallner, A.; Wild, E.

    2000-01-01

    The possibilities of computer-assisted and automated accelerator mass spectrometry (AMS) measurements were explored. The goal of these efforts is to develop fully automated procedures for 'routine' measurements at the Vienna Environmental Research Accelerator (VERA), a dedicated 3-MV Pelletron tandem AMS facility. As a new tool for automatic tuning of the ion optics we developed a multi-dimensional optimization algorithm robust to noise, which was applied for 14 C and 10 Be. The actual isotope ratio measurements are performed in a fully automated fashion and do not require the presence of an operator. Incoming data are evaluated online and the results can be accessed via Internet. The system was used for 14 C, 10 Be, 26 Al and 129 I measurements

  8. Implants for orthodontic anchorage

    Zheng, Xiaowen; Sun, Yannan; Zhang, Yimei; Cai, Ting; Sun, Feng; Lin, Jiuxiang

    2018-01-01

    Abstract Implantanchorage continues to receive much attention as an important orthodontic anchorage. Since the development of orthodontic implants, the scope of applications has continued to increase. Although multiple reviews detailing implants have been published, no comprehensive evaluations have been performed. Thus, the purpose of this study was to comprehensively evaluate the effects of implants based on data published in review articles. An electronic search of the Cochrane Library, Medline, Embase, Ebsco and Sicencedirect for reviews with “orthodontic” and “systematic review or meta analysis” in the title, abstract, keywords, or full text was performed. A subsequent manual search was then performed to identify reviews concerning orthodontic implants. A manual search of the orthodontic journals American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), European Journal of Orthodontics (EJO), and Angle Othodontist was also performed. Such systematic reviews that evaluated the efficacy and safety of orthodontic implants were used to indicate success rates and molar movements. A total of 23 reviews were included in the analysis. The quality of each review was assessed using a measurement tool for Assessment of Multiple Systematic Reviews (AMSTAR), and the review chosen to summarize outcomes had a quality score of >6. Most reviews were less than moderate quality. Success rates of implants ranged in a broad scope, and movement of the maxillary first molar was superior with implants compared with traditional anchorage. PMID:29595673

  9. Maintenance in dental implants

    Giselle Póvoa Gomes

    2008-01-01

    Full Text Available In implants, maintenance is a decisive factor for obtaining success when implant supported overdentures and dentures are used. The present stud presents, a clinical case of a patient, a 70 year-old white man, with a completely edentulous mandibular alveolar ridge, severe bone resorption with presence of basal bone only, and absence of vestibule. Initially, treatment consisted of the placement of a mandibular overdenture, supported on three implants in the anterior inter-foramen region, as the left implant was transfixed in the basal bone of 2 to 3 millimeters. Eleven years later, another two implants were placed in the anterior area and an immediate load was performed up to the first molars, for the placement of an implant supported fixed. Throughout the entire treatment, meticulous maintenance was carried out, with follow-up for fourteen years, interrupted by the patient’s death. From the third month after the opening the three implants initially placed, the presence of keratinized mucosa, definition of the vestibule, maturation of the alveolar ridge and bone formation in the mento region were observed. It was concluded that good planning, allied to mastery of the technique and adequate maintenance were the prerequisites necessary for obtaining favorable results, success of the present case, and for the patient to have a better quality of life.

  10. FMFT. Fully massive four-loop tadpoles

    Pikelner, Andrey [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2017-07-15

    We present FMFT - a package written in FORM that evaluates four-loop fully massive tadpole Feynman diagrams. It is a successor of the MATAD package that has been successfully used to calculate many renormalization group functions at three-loop order in a wide range of quantum field theories especially in the Standard Model. We describe an internal structure of the package and provide some examples of its usage.

  11. Fully NLO Parton Shower in QCD

    Skrzypek, M.; Jadach, S.; Slawinska, M.; Gituliar, O.; Kusina, A.; Placzek, W.

    2011-01-01

    The project of constructing a complete NLO-level Parton Shower Monte Carlo for the QCD processes developed in IFJ PAN in Krakow is reviewed. Four issues are discussed: (1) the extension of the standard inclusive collinear factorization into a new, fully exclusive scheme; (2) reconstruction of the LO Parton Shower in the new scheme; (3) inclusion of the exclusive NLO corrections into the hard process and (4) inclusion of the exclusive NLO corrections into the evolution (ladder) part. (authors)

  12. FMFT: fully massive four-loop tadpoles

    Pikelner, Andrey

    2018-03-01

    We present FMFT - a package written in FORM that evaluates four-loop fully massive tadpole Feynman diagrams. It is a successor of the MATAD package that has been successfully used to calculate many renormalization group functions at three-loop order in a wide range of quantum field theories especially in the Standard Model. We describe an internal structure of the package and provide some examples of its usage.

  13. Fully probabilistic design of hierarchical Bayesian models

    Quinn, A.; Kárný, Miroslav; Guy, Tatiana Valentine

    2016-01-01

    Roč. 369, č. 1 (2016), s. 532-547 ISSN 0020-0255 R&D Projects: GA ČR GA13-13502S Institutional support: RVO:67985556 Keywords : Fully probabilistic design * Ideal distribution * Minimum cross-entropy principle * Bayesian conditioning * Kullback-Leibler divergence * Bayesian nonparametric modelling Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 4.832, year: 2016 http://library.utia.cas.cz/separaty/2016/AS/karny-0463052.pdf

  14. Fully implicit kinetic modelling of collisional plasmas

    Mousseau, V.A.

    1996-05-01

    This dissertation describes a numerical technique, Matrix-Free Newton Krylov, for solving a simplified Vlasov-Fokker-Planck equation. This method is both deterministic and fully implicit, and may not have been a viable option before current developments in numerical methods. Results are presented that indicate the efficiency of the Matrix-Free Newton Krylov method for these fully-coupled, nonlinear integro-differential equations. The use and requirement for advanced differencing is also shown. To this end, implementations of Chang-Cooper differencing and flux limited Quadratic Upstream Interpolation for Convective Kinematics (QUICK) are presented. Results are given for a fully kinetic ion-electron problem with a self consistent electric field calculated from the ion and electron distribution functions. This numerical method, including advanced differencing, provides accurate solutions, which quickly converge on workstation class machines. It is demonstrated that efficient steady-state solutions can be achieved to the non-linear integro-differential equation, obtaining quadratic convergence, without incurring the large memory requirements of an integral operator. Model problems are presented which simulate plasma impinging on a plate with both high and low neutral particle recycling typical of a divertor in a Tokamak device. These model problems demonstrate the performance of the new solution method

  15. Nanotechnology for dental implants.

    Tomsia, Antoni P; Lee, Janice S; Wegst, Ulrike G K; Saiz, Eduardo

    2013-01-01

    With the advent of nanotechnology, an opportunity exists for the engineering of new dental implant materials. Metallic dental implants have been successfully used for decades, but they have shortcomings related to osseointegration and mechanical properties that do not match those of bone. Absent the development of an entirely new class of materials, faster osseointegration of currently available dental implants can be accomplished by various surface modifications. To date, there is no consensus regarding the preferred method(s) of implant surface modification, and further development will be required before the ideal implant surface can be created, let alone become available for clinical use. Current approaches can generally be categorized into three areas: ceramic coatings, surface functionalization, and patterning on the micro- to nanoscale. The distinctions among these are imprecise, as some or all of these approaches can be combined to improve in vivo implant performance. These surface improvements have resulted in durable implants with a high percentage of success and long-term function. Nanotechnology has provided another set of opportunities for the manipulation of implant surfaces in its capacity to mimic the surface topography formed by extracellular matrix components of natural tissue. The possibilities introduced by nanotechnology now permit the tailoring of implant chemistry and structure with an unprecedented degree of control. For the first time, tools are available that can be used to manipulate the physicochemical environment and monitor key cellular events at the molecular level. These new tools and capabilities will result in faster bone formation, reduced healing time, and rapid recovery to function.

  16. Recrystallization of implanted amorphous silicon layers. I. Electrical properties of silicon implanted with BF+2 or Si++B+

    Tsai, M.Y.; Streetman, B.G.

    1979-01-01

    Electrical properties of recrystallized amorphous silicon layers, formed by BF + 2 implants or Si + +B + implants, have been studied by differential resistivity and Hall-effect measurements. Electrical carrier distribution profiles show that boron atoms inside the amorphized Si layers can be fully activated during recrystallization at 550 0 C. The mobility is also recovered. However, the tail of the B distribution, located inside a damaged region near the original amorphous-crystalline interface, remains inactive. This inactive tail has been observed for all samples implanted with BF + 2 . Only in a thicker amorphous layer, formed for example by Si + predamage implants, can the entire B profile be activated. The etch rate of amorphous silicon in HF and the effect of fluorine on the recrystallization rate are also reported

  17. Ion implantation for microelectronics

    Dearnaley, G.

    1977-01-01

    Ion implantation has proved to be a versatile and efficient means of producing microelectronic devices. This review summarizes the relevant physics and technology and assesses the advantages of the method. Examples are then given of widely different device structures which have been made by ion implantation. While most of the industrial application has been in silicon, good progress continues to be made in the more difficult field of compound semiconductors. Equipment designed for the industrial ion implantation of microelectronic devices is discussed briefly. (Auth.)

  18. Optimization of dental implantation

    Dol, Aleksandr V.; Ivanov, Dmitriy V.

    2017-02-01

    Modern dentistry can not exist without dental implantation. This work is devoted to study of the "bone-implant" system and to optimization of dental prostheses installation. Modern non-invasive methods such as MRI an 3D-scanning as well as numerical calculations and 3D-prototyping allow to optimize all of stages of dental prosthetics. An integrated approach to the planning of implant surgery can significantly reduce the risk of complications in the first few days after treatment, and throughout the period of operation of the prosthesis.

  19. Decoronation followed by dental implants placement: fundamentals, applications and explanations

    Consolaro, Alberto; Ribeiro, Paulo Domingos; Cardoso, Maurício A.; Miranda, Dario A. Oliveira; Salfatis, Monica

    2018-01-01

    ABSTRACT Dental arches areas with teeth presenting dentoalveolar ankylosis and replacement root resorption can be considered as presenting normal bone, in full physiological remodeling process; and osseointegrated implants can be successfully placed. Bone remodeling will promote osseointegration, regardless of presenting ankylosis and/or replacement root resorption. After 1 to 10 years, all dental tissues will have been replaced by bone. The site, angulation and ideal positioning in the space to place the implant should be dictated exclusively by the clinical convenience, associated with previous planning. One of the advantages of decoronation followed by dental implants placement in ankylosed teeth with replacement resorption is the maintenance of bone volume in the region, both vertical and horizontal. If possible, the buccal part of the root, even if thin, should be preserved in the preparation of the cavity for the implant, as this will maintain gingival tissues looking fully normal for long periods. In the selection of cases for decoronation, the absence of microbial contamination in the region - represented by chronic periapical lesions, presence of fistula, old unconsolidated root fractures and active advanced periodontal disease - is important. Such situations are contraindications to decoronation. However, the occurrence of dentoalveolar ankylosis and replacement resorption without contamination should neither change the planning for implant installation, nor the criteria for choosing the type and brand of dental implant to be used. Failure to decoronate and use dental implants has never been reported. PMID:29791693

  20. Breast Reconstruction with Implants

    ... your surgical options and discuss the advantages and disadvantages of implant-based reconstruction, and may show you ... Policy Notice of Privacy Practices Notice of Nondiscrimination Advertising Mayo Clinic is a not-for-profit organization ...

  1. Ion Implantation of Polymers

    Popok, Vladimir

    2012-01-01

    The current paper presents a state-of-the-art review in the field of ion implantation of polymers. Numerous published studies of polymers modified by ion beams are analysed. General aspects of ion stopping, latent track formation and changes of structure and composition of organic materials...... are discussed. Related to that, the effects of radiothermolysis, degassing and carbonisation are considered. Specificity of depth distributions of implanted into polymers impurities is analysed and the case of high-fluence implantation is emphasised. Within rather broad topic of ion bombardment, the focus...... is put on the low-energy implantation of metal ions causing the nucleation and growth of nanoparticles in the shallow polymer layers. Electrical, optical and magnetic properties of metal/polymer composites are under the discussion and the approaches towards practical applications are overviewed....

  2. Precipitation processes in implanted materials

    Borders, J.A.

    1978-01-01

    Ion implantation is a nonequilibrium process. It is possible to implant materials with impurities to concentration levels which exceed the solid solubilities. The return of the system to thermodynamic equilibrium is often accomplished by precipitation of the implanted species or a compound involving atoms of both the host and the implanted species. This may involve long time scales when taking place at room temperature or it may take place during the implantation

  3. Ion implantation for semiconductors

    Grey-Morgan, T.

    1995-01-01

    Full text: Over the past two decades, thousands of particle accelerators have been used to implant foreign atoms like boron, phosphorus and arsenic into silicon crystal wafers to produce special embedded layers for manufacturing semiconductor devices. Depending on the device required, the atomic species, the depth of implant and doping levels are the main parameters for the implantation process; the selection and parameter control is totally automated. The depth of the implant, usually less than 1 micron, is determined by the ion energy, which can be varied between 2 and 600 keV. The ion beam is extracted from a Freeman or Bernas type ion source and accelerated to 60 keV before mass analysis. For higher beam energies postacceleration is applied up to 200 keV and even higher energies can be achieved by mass selecting multiplycharged ions, but with a corresponding reduction in beam output. Depending on the device to be manufactured, doping levels can range from 10 10 to 10 15 atoms/cm 2 and are controlled by implanter beam currents in the range up to 30mA; continuous process monitoring ensures uniformity across the wafer of better than 1 % . As semiconductor devices get smaller, additional sophistication is required in the design of the implanter. The silicon wafers charge electrically during implantation and this charge must be dissipated continuously to reduce the electrical stress in the device and avoid destructive electrical breakdown. Electron flood guns produce low energy electrons (below 10 electronvolts) to neutralize positive charge buildup and implanter design must ensure minimum contamination by other isotopic species and ensure low internal sputter rates. The pace of technology in the semiconductor industry is such that implanters are being built now for 256 Megabit circuits but which are only likely to be widely available five years from now. Several specialist companies manufacture implanter systems, each costing around US$5 million, depending on the

  4. Quantitative ion implantation

    Gries, W.H.

    1976-06-01

    This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertaken to investigate the possibility of accurate portioning of matter in submicrogram quantities, with some specific applications in mind. The problem is extensively investigated both on a theoretical level and in practice. A mathematical model is developed for calculating the loss of implanted ions by resputtering as a function of the implanted ion dose and the sputtering yield. Numerical data are produced therefrom which permit a good order-of-magnitude estimate of the loss for any ion/solid combination in which the ions are heavier than the solid atoms, and for any ion energy from 10 to 300 keV. The implanted ion dose is measured by integration of the ion beam current, and equipment and techniques are described which make possible the accurate integration of an ion current in an electromagnetic isotope separator. The methods are applied to two sample cases, one being a stable isotope, the other a radioisotope. In both cases independent methods are used to show that the implantation is indeed quantitative, as predicted. At the same time the sample cases are used to demonstrate two possible applications for quantitative ion implantation, viz. firstly for the manufacture of calibration standards for instrumental micromethods of elemental trace analysis in metals, and secondly for the determination of the half-lives of long-lived radioisotopes by a specific activity method. It is concluded that the present study has advanced quantitative ion implantation to the state where it can be successfully applied to the solution of problems in other fields

  5. Ion implantation - an introduction

    Townsend, P.D.

    1986-01-01

    Ion implantation is a widely used technique with a literature that covers semiconductor production, surface treatments of steels, corrosion resistance, catalysis and integrated optics. This brief introduction outlines advantages of the technique, some aspects of the underlying physics and examples of current applications. Ion implantation is already an essential part of semiconductor technology while in many other areas it is still in an early stage of development. The future scope of the subject is discussed. (author)

  6. Anodized dental implant surface

    Sunil Kumar Mishra

    2017-01-01

    Full Text Available Purpose: Anodized implants with moderately rough surface were introduced around 2000. Whether these implants enhanced biologic effect to improve the environment for better osseointegration was unclear. The purpose of this article was to review the literature available on anodized surface in terms of their clinical success rate and bone response in patients till now. Materials and Methods: A broad electronic search of MEDLINE and PubMed databases was performed. A focus was made on peer-reviewed dental journals. Only articles related to anodized implants were included. Both animal and human studies were included. Results: The initial search of articles resulted in 581 articles on anodized implants. The initial screening of titles and abstracts resulted in 112 full-text papers; 40 animal studies, 16 studies on cell adhesion and bacterial adhesion onto anodized surfaced implants, and 47 human studies were included. Nine studies, which do not fulfill the inclusion criteria, were excluded. Conclusions: The long-term studies on anodized surface implants do favor the surface, but in most of the studies, anodized surface is compared with that of machined surface, but not with other surfaces commercially available. Anodized surface in terms of clinical success rate in cases of compromised bone and immediately extracted sockets has shown favorable success.

  7. Plasma source ion implantation

    Conrad, J.R.; Forest, C.

    1986-01-01

    The authors' technique allows the ion implantation to be performed directly within the ion source at higher currents without ion beam extraction and transport. The potential benefits include greatly increased production rates (factors of 10-1000) and the ability to implant non-planar targets without rastering or shadowing. The technique eliminates the ion extractor grid set, beam raster equipment, drift space and target manipulator equipment. The target to be implanted is placed directly within the plasma source and is biased to a large negative potential so that plasma ions gain energy as they accelerate through the potential drop across the sheath that forms at the plasma boundary. Because the sheath surrounds the target on all sides, all surfaces of the target are implanted without the necessity to raster the beam or to rotate the target. The authors have succeeded in implanting nitrogen ions in a silicon target to the depths and concentrations required for surface treatment of materials like stainless steel and titanium alloys. They have performed ESCA measurements of the penetration depth profile of a silicon target that was biased to 30 kV in a nitrogen discharge plasma. Nitrogen ions were implanted to a depth of 700A at a peak concentration of 30% atomic. The measured profile is quite similar to a previously obtained profile in titanium targets with conventional techniques

  8. Argentina to fully privatize state owned YPF

    Anon.

    1992-01-01

    Argentina's Congress has voted to fully privatize state petroleum company Yacimientos Petroliferos Fiscales (YPF), a move the government expects to net at least $8 billion. Despite some political opposition, the vote was 119-10 in favor, with one abstention and opposition party members refusing to participate in the vote. Argentina's President Carlos Menem had threatened to authorize YPF privatization by decree if there was no quorum for a vote. YPF is responsible for 40% of Argentina's oil production. The country h as been self-sufficient in crude since 1982. Current production is 563,472 b/d, and proved reserves of oil and gas are valued at $7 billion

  9. Short dental implants: an emerging concept in implant treatment.

    Al-Hashedi, Ashwaq Ali; Taiyeb Ali, Tara Bai; Yunus, Norsiah

    2014-06-01

    Short implants have been advocated as a treatment option in many clinical situations where the use of conventional implants is limited. This review outlines the effectiveness and clinical outcomes of using short implants as a valid treatment option in the rehabilitation of edentulous atrophic alveolar ridges. Initially, an electronic search was performed on the following databases: Medline, PubMed, Embase, Cochrane Database of Systematic Reviews, and DARE using key words from January 1990 until May 2012. An additional hand search was included for the relevant articles in the following journals: International Journal of Oral and Maxillofacial Implants, Clinical Oral Implants Research, Journal of Clinical Periodontology, International Journal of Periodontics, Journal of Periodontology, and Clinical Implant Dentistry and Related Research. Any relevant papers from the journals' references were hand searched. Articles were included if they provided detailed data on implant length, reported survival rates, mentioned measures for implant failure, were in the English language, involved human subjects, and researched implants inserted in healed atrophic ridges with a follow-up period of at least 1 year after implant-prosthesis loading. Short implants demonstrated a high rate of success in the replacement of missing teeth in especially atrophic alveolar ridges. The advanced technology and improvement of the implant surfaces have encouraged the success of short implants to a comparable level to that of standard implants. However, further randomized controlled clinical trials and prospective studies with longer follow-up periods are needed.

  10. Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted $^{163}$Ho ions

    Gastaldo, L.; von Seggern, F.; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

    2013-01-01

    For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of $^{163}$Ho using MMCs having the radioactive $^{163}$Ho ions implanted in the absorber. The implantation of $^{163}$Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. In addition an optimized detector design for future $^{163}$Ho experiments is presented.

  11. Fully 3D GPU PET reconstruction

    Herraiz, J.L., E-mail: joaquin@nuclear.fis.ucm.es [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Espana, S. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Cal-Gonzalez, J. [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Vaquero, J.J. [Departmento de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Desco, M. [Departmento de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Udias, J.M. [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain)

    2011-08-21

    Fully 3D iterative tomographic image reconstruction is computationally very demanding. Graphics Processing Unit (GPU) has been proposed for many years as potential accelerators in complex scientific problems, but it has not been used until the recent advances in the programmability of GPUs that the best available reconstruction codes have started to be implemented to be run on GPUs. This work presents a GPU-based fully 3D PET iterative reconstruction software. This new code may reconstruct sinogram data from several commercially available PET scanners. The most important and time-consuming parts of the code, the forward and backward projection operations, are based on an accurate model of the scanner obtained with the Monte Carlo code PeneloPET and they have been massively parallelized on the GPU. For the PET scanners considered, the GPU-based code is more than 70 times faster than a similar code running on a single core of a fast CPU, obtaining in both cases the same images. The code has been designed to be easily adapted to reconstruct sinograms from any other PET scanner, including scanner prototypes.

  12. Fully 3D GPU PET reconstruction

    Herraiz, J.L.; Espana, S.; Cal-Gonzalez, J.; Vaquero, J.J.; Desco, M.; Udias, J.M.

    2011-01-01

    Fully 3D iterative tomographic image reconstruction is computationally very demanding. Graphics Processing Unit (GPU) has been proposed for many years as potential accelerators in complex scientific problems, but it has not been used until the recent advances in the programmability of GPUs that the best available reconstruction codes have started to be implemented to be run on GPUs. This work presents a GPU-based fully 3D PET iterative reconstruction software. This new code may reconstruct sinogram data from several commercially available PET scanners. The most important and time-consuming parts of the code, the forward and backward projection operations, are based on an accurate model of the scanner obtained with the Monte Carlo code PeneloPET and they have been massively parallelized on the GPU. For the PET scanners considered, the GPU-based code is more than 70 times faster than a similar code running on a single core of a fast CPU, obtaining in both cases the same images. The code has been designed to be easily adapted to reconstruct sinograms from any other PET scanner, including scanner prototypes.

  13. Fully populated VCM or the hidden parameter

    Kermarrec G.

    2017-11-01

    Full Text Available Least-squares estimates are trustworthy with minimal variance if the correct stochastic model is used. Due to computational burden, diagonal models that neglect correlations are preferred to describe the elevation dependency of the variance of GPS observations. In this contribution, an improved stochastic model based on a parametric function to take correlations between GPS phase observations into account is presented. Built on an adapted and flexible Mátern function accounting for spatiotemporal variabilities, its parameters can be fixed thanks to Maximum Likelihood Estimation or chosen apriori to model turbulent tropospheric refractivity fluctuations. In this contribution, we will show in which cases and under which conditions corresponding fully populated variance covariance matrices (VCM replace the estimation of a tropospheric parameter. For this equivalence “augmented functional versus augmented stochastic model” to hold, the VCM should be made sufficiently largewhich corresponds to computing small batches of observations. A case study with observations from a medium baseline of 80 km divided into batches of 600 s shows improvement of up to 100 mm for the 3Drms when fully populated VCM are used compared with an elevation dependent diagonal model. It confirms the strong potential of such matrices to improve the least-squares solution, particularly when ambiguities are let float.

  14. Communication: Fully coherent quantum state hopping

    Martens, Craig C., E-mail: cmartens@uci.edu [University of California, Irvine, California 92697-2025 (United States)

    2015-10-14

    In this paper, we describe a new and fully coherent stochastic surface hopping method for simulating mixed quantum-classical systems. We illustrate the approach on the simple but unforgiving problem of quantum evolution of a two-state quantum system in the limit of unperturbed pure state dynamics and for dissipative evolution in the presence of both stationary and nonstationary random environments. We formulate our approach in the Liouville representation and describe the density matrix elements by ensembles of trajectories. Population dynamics are represented by stochastic surface hops for trajectories representing diagonal density matrix elements. These are combined with an unconventional coherent stochastic hopping algorithm for trajectories representing off-diagonal quantum coherences. The latter generalizes the binary (0,1) “probability” of a trajectory to be associated with a given state to allow integers that can be negative or greater than unity in magnitude. Unlike existing surface hopping methods, the dynamics of the ensembles are fully entangled, correctly capturing the coherent and nonlocal structure of quantum mechanics.

  15. Fully CMOS-compatible titanium nitride nanoantennas

    Briggs, Justin A., E-mail: jabriggs@stanford.edu [Department of Applied Physics, Stanford University, 348 Via Pueblo Mall, Stanford, California 94305 (United States); Department of Materials Science and Engineering, Stanford University, 496 Lomita Mall, Stanford, California 94305 (United States); Naik, Gururaj V.; Baum, Brian K.; Dionne, Jennifer A. [Department of Materials Science and Engineering, Stanford University, 496 Lomita Mall, Stanford, California 94305 (United States); Petach, Trevor A.; Goldhaber-Gordon, David [Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States)

    2016-02-01

    CMOS-compatible fabrication of plasmonic materials and devices will accelerate the development of integrated nanophotonics for information processing applications. Using low-temperature plasma-enhanced atomic layer deposition (PEALD), we develop a recipe for fully CMOS-compatible titanium nitride (TiN) that is plasmonic in the visible and near infrared. Films are grown on silicon, silicon dioxide, and epitaxially on magnesium oxide substrates. By optimizing the plasma exposure per growth cycle during PEALD, carbon and oxygen contamination are reduced, lowering undesirable loss. We use electron beam lithography to pattern TiN nanopillars with varying diameters on silicon in large-area arrays. In the first reported single-particle measurements on plasmonic TiN, we demonstrate size-tunable darkfield scattering spectroscopy in the visible and near infrared regimes. The optical properties of this CMOS-compatible material, combined with its high melting temperature and mechanical durability, comprise a step towards fully CMOS-integrated nanophotonic information processing.

  16. Comparison of naturally occurring and ligature-induced peri-implantitis bone defects in humans and dogs.

    Schwarz, F.; Herten, M. van; Sager, M.; Bieling, K.; Sculean, A.; Becker, J.

    2007-01-01

    OBJECTIVES: The aim of the present study was to evaluate and compare naturally occuring and ligature-induced peri-implantitis bone defects in humans and dogs. MATERIAL AND METHODS: Twenty-four partially and fully edentulous patients undergoing peri-implant bone augmentation procedures due to

  17. Experiences from Auditory Brainstem Implantation (ABIs) in four paediatric patients.

    Lundin, Karin; Stillesjö, Fredrik; Nyberg, Gunnar; Rask-Andersen, Helge

    2016-01-01

    Indications for auditory brainstem implants (ABIs) have been widened from patients with neurofibromatosis type 2 (NF2) to paediatric patients with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, or cochlear ossification after meningitis. We present four ABI surgeries performed in children at Uppsala University Hospital in Sweden since 2009. Three children were implanted with implants from Cochlear Ltd. (Lane Cove, Australia) and one child with an implant from MedEl GMBH (Innsbruck, Austria). A boy with Goldenhar syndrome was implanted with a Cochlear Nucleus ABI24M at age 2 years (patient 1). Another boy with CHARGE syndrome was implanted with a Cochlear Nucleus ABI541 at age 2.5 years (patient 2). Another boy with post-ossification meningitis was implanted with a Cochlear Nucleus ABI24M at age 4 years (patient 3). A girl with cochlear aplasia was implanted with a MedEl Synchrony ABI at age 3 years (patient 4). In patients 1, 2, and 3, the trans-labyrinthine approach was used, and in patient 4 the retro-sigmoid approach was used. Three of the four children benefited from their ABIs and use it full time. Two of the full time users had categories of auditory performance (CAP) score of 4 at their last follow up visit (6 and 2.5 years postoperative) which means they can discriminate consistently any combination of two of Ling's sounds. One child has not been fully evaluated yet, but is a full time user and had CAP 2 (responds to speech sounds) after 3 months of ABI use. No severe side or unpleasant stimulation effects have been observed so far. There was one case of immediate electrode migration and one case of implant device failure after 6.5 years. ABI should be considered as an option in the rehabilitation of children with similar diagnoses.

  18. Fully Printed Flexible and Stretchable Electronics

    Zhang, Suoming

    Through this thesis proposal, the author has demonstrated series of flexible or stretchable sensors including strain gauge, pressure sensors, display arrays, thin film transistors and photodetectors fabricated by a direct printing process. By adopting the novel serpentine configuration with conventional non-stretchable materials silver nanoparticles, the fully printed stretchable devices are successfully fabricated on elastomeric substrate with the demonstration of stretchable conductors that can maintain the electrical properties under strain and the strain gauge, which could be used to measure the strain in desired locations and also to monitor individual person's finger motion. And by investigating the intrinsic stretchable materials silver nanowires (AgNWs) with the conventional configuration, the fully printed stretchable conductors are achieved on various substrates including Si, glass, Polyimide, Polydimethylsiloxane (PDMS) and Very High Bond (VHB) tape with the illustration of the capacitive pressure sensor and stretchable electroluminescent displays. In addition, intrinsically stretchable thin-film transistors (TFTs) and integrated logic circuits are directly printed on elastomeric PDMS substrates. The printed devices utilize carbon nanotubes and a type of hybrid gate dielectric comprising PDMS and barium titanate (BaTiO3) nanoparticles. The BaTiO3/PDMS composite simultaneously provides high dielectric constant, superior stretchability, low leakage, as well as good printability and compatibility with the elastomeric substrate. Both TFTs and logic circuits can be stretched beyond 50% strain along either channel length or channel width directions for thousands of cycles while showing no significant degradation in electrical performance. Finally, by applying the SWNTs as the channel layer of the thin film transistor, we successfully fabricate the fully printed flexible photodetector which exhibits good electrical characteristics and the transistors exhibit

  19. A Fully Automated Penumbra Segmentation Tool

    Nagenthiraja, Kartheeban; Ribe, Lars Riisgaard; Hougaard, Kristina Dupont

    2012-01-01

    Introduction: Perfusion- and diffusion weighted MRI (PWI/DWI) is widely used to select patients who are likely to benefit from recanalization therapy. The visual identification of PWI-DWI-mismatch tissue depends strongly on the observer, prompting a need for software, which estimates potentially...... salavageable tissue, quickly and accurately. We present a fully Automated Penumbra Segmentation (APS) algorithm using PWI and DWI images. We compare automatically generated PWI-DWI mismatch mask to mask outlined manually by experts, in 168 patients. Method: The algorithm initially identifies PWI lesions......) at 600∙10-6 mm2/sec. Due to the nature of thresholding, the ADC mask overestimates the DWI lesion volume and consequently we initialized level-set algorithm on DWI image with ADC mask as prior knowledge. Combining the PWI and inverted DWI mask then yield the PWI-DWI mismatch mask. Four expert raters...

  20. Simulations of fully deformed oscillating flux tubes

    Karampelas, K.; Van Doorsselaere, T.

    2018-02-01

    Context. In recent years, a number of numerical studies have been focusing on the significance of the Kelvin-Helmholtz instability in the dynamics of oscillating coronal loops. This process enhances the transfer of energy into smaller scales, and has been connected with heating of coronal loops, when dissipation mechanisms, such as resistivity, are considered. However, the turbulent layer is expected near the outer regions of the loops. Therefore, the effects of wave heating are expected to be confined to the loop's external layers, leaving their denser inner parts without a heating mechanism. Aim. In the current work we aim to study the spatial evolution of wave heating effects from a footpoint driven standing kink wave in a coronal loop. Methods: Using the MPI-AMRVAC code, we performed ideal, three dimensional magnetohydrodynamic simulations of footpoint driven transverse oscillations of a cold, straight coronal flux tube, embedded in a hotter environment. We have also constructed forward models for our simulation using the FoMo code. Results: The developed transverse wave induced Kelvin-Helmholtz (TWIKH) rolls expand throughout the tube cross-section, and cover it entirely. This turbulence significantly alters the initial density profile, leading to a fully deformed cross section. As a consequence, the resistive and viscous heating rate both increase over the entire loop cross section. The resistive heating rate takes its maximum values near the footpoints, while the viscous heating rate at the apex. Conclusions: We conclude that even a monoperiodic driver can spread wave heating over the whole loop cross section, potentially providing a heating source in the inner loop region. Despite the loop's fully deformed structure, forward modelling still shows the structure appearing as a loop. A movie attached to Fig. 1 is available at http://https://www.aanda.org

  1. Lidar Cloud Detection with Fully Convolutional Networks

    Cromwell, E.; Flynn, D.

    2017-12-01

    The vertical distribution of clouds from active remote sensing instrumentation is a widely used data product from global atmospheric measuring sites. The presence of clouds can be expressed as a binary cloud mask and is a primary input for climate modeling efforts and cloud formation studies. Current cloud detection algorithms producing these masks do not accurately identify the cloud boundaries and tend to oversample or over-represent the cloud. This translates as uncertainty for assessing the radiative impact of clouds and tracking changes in cloud climatologies. The Atmospheric Radiation Measurement (ARM) program has over 20 years of micro-pulse lidar (MPL) and High Spectral Resolution Lidar (HSRL) instrument data and companion automated cloud mask product at the mid-latitude Southern Great Plains (SGP) and the polar North Slope of Alaska (NSA) atmospheric observatory. Using this data, we train a fully convolutional network (FCN) with semi-supervised learning to segment lidar imagery into geometric time-height cloud locations for the SGP site and MPL instrument. We then use transfer learning to train a FCN for (1) the MPL instrument at the NSA site and (2) for the HSRL. In our semi-supervised approach, we pre-train the classification layers of the FCN with weakly labeled lidar data. Then, we facilitate end-to-end unsupervised pre-training and transition to fully supervised learning with ground truth labeled data. Our goal is to improve the cloud mask accuracy and precision for the MPL instrument to 95% and 80%, respectively, compared to the current cloud mask algorithms of 89% and 50%. For the transfer learning based FCN for the HSRL instrument, our goal is to achieve a cloud mask accuracy of 90% and a precision of 80%.

  2. A novel fully integrated handheld gamma camera

    Massari, R.; Ucci, A.; Campisi, C.; Scopinaro, F.; Soluri, A.

    2016-01-01

    In this paper, we present an innovative, fully integrated handheld gamma camera, namely designed to gather in the same device the gamma ray detector with the display and the embedded computing system. The low power consumption allows the prototype to be battery operated. To be useful in radioguided surgery, an intraoperative gamma camera must be very easy to handle since it must be moved to find a suitable view. Consequently, we have developed the first prototype of a fully integrated, compact and lightweight gamma camera for radiopharmaceuticals fast imaging. The device can operate without cables across the sterile field, so it may be easily used in the operating theater for radioguided surgery. The prototype proposed consists of a Silicon Photomultiplier (SiPM) array coupled with a proprietary scintillation structure based on CsI(Tl) crystals. To read the SiPM output signals, we have developed a very low power readout electronics and a dedicated analog to digital conversion system. One of the most critical aspects we faced designing the prototype was the low power consumption, which is mandatory to develop a battery operated device. We have applied this detection device in the lymphoscintigraphy technique (sentinel lymph node mapping) comparing the results obtained with those of a commercial gamma camera (Philips SKYLight). The results obtained confirm a rapid response of the device and an adequate spatial resolution for the use in the scintigraphic imaging. This work confirms the feasibility of a small gamma camera with an integrated display. This device is designed for radioguided surgery and small organ imaging, but it could be easily combined into surgical navigation systems.

  3. A novel fully integrated handheld gamma camera

    Massari, R.; Ucci, A.; Campisi, C. [Biostructure and Bioimaging Institute (IBB), National Research Council of Italy (CNR), Rome (Italy); Scopinaro, F. [University of Rome “La Sapienza”, S. Andrea Hospital, Rome (Italy); Soluri, A., E-mail: alessandro.soluri@ibb.cnr.it [Biostructure and Bioimaging Institute (IBB), National Research Council of Italy (CNR), Rome (Italy)

    2016-10-01

    In this paper, we present an innovative, fully integrated handheld gamma camera, namely designed to gather in the same device the gamma ray detector with the display and the embedded computing system. The low power consumption allows the prototype to be battery operated. To be useful in radioguided surgery, an intraoperative gamma camera must be very easy to handle since it must be moved to find a suitable view. Consequently, we have developed the first prototype of a fully integrated, compact and lightweight gamma camera for radiopharmaceuticals fast imaging. The device can operate without cables across the sterile field, so it may be easily used in the operating theater for radioguided surgery. The prototype proposed consists of a Silicon Photomultiplier (SiPM) array coupled with a proprietary scintillation structure based on CsI(Tl) crystals. To read the SiPM output signals, we have developed a very low power readout electronics and a dedicated analog to digital conversion system. One of the most critical aspects we faced designing the prototype was the low power consumption, which is mandatory to develop a battery operated device. We have applied this detection device in the lymphoscintigraphy technique (sentinel lymph node mapping) comparing the results obtained with those of a commercial gamma camera (Philips SKYLight). The results obtained confirm a rapid response of the device and an adequate spatial resolution for the use in the scintigraphic imaging. This work confirms the feasibility of a small gamma camera with an integrated display. This device is designed for radioguided surgery and small organ imaging, but it could be easily combined into surgical navigation systems.

  4. [Bilateral cochlear implants].

    Müller, J

    2017-07-01

    Cochlear implants (CI) are standard for the hearing rehabilitation of severe to profound deafness. Nowadays, if bilaterally indicated, bilateral implantation is usually recommended (in accordance with German guidelines). Bilateral implantation enables better speech discrimination in quiet and in noise, and restores directional and spatial hearing. Children with bilateral CI are able to undergo hearing-based hearing and speech development. Within the scope of their individual possibilities, bilaterally implanted children develop faster than children with unilateral CI and attain, e.g., a larger vocabulary within a certain time interval. Only bilateral implantation allows "binaural hearing," with all the benefits that people with normal hearing profit from, namely: better speech discrimination in quiet and in noise, as well as directional and spatial hearing. Naturally, the developments take time. Binaural CI users benefit from the same effects as normal hearing persons: head shadow effect, squelch effect, and summation and redundancy effects. Sequential CI fitting is not necessarily disadvantageous-both simultaneously and sequentially fitted patients benefit in a similar way. For children, earliest possible fitting and shortest possible interval between the two surgeries seems to positively influence the outcome if bilateral CI are indicated.

  5. Terminal Posterior Tilted Implants Planned as a Sinus Graft Alternative for Fixed Full-Arch Implant-Supported Maxillary Restoration: A Case Series with 10- to 19-Year Results on 44 Consecutive Patients Presenting for Routine Maintenance.

    Fortin, Yvan; Sullivan, Richard M

    2017-02-01

    Posterior maxillary tilted implants are gaining prevalence as an alternative to sinus grafts supporting fixed maxillary restorations. This paper reports long-term results after loading using this technique. Consecutive patients presenting for either routine hygiene maintenance or unplanned emergency care who had received tilted implants as a sinus graft alternative to support fixed fully implant-supported restoration of an edentulous maxilla and were followed for a minimum of 10 years from initial implant placement were included in this evaluation. Forty-four patients were identified: 40 with bilateral tilted implants and 4 with one tilted and one axial posterior implant. Eight patients received one-piece fixed porcelain-to-gold screw-retained restorations, and thirty-six patients received a fully implant-supported patient-removable Marius Bridge. Seventy-nine out of 84 originally loaded posterior tilted implants survived a minimum of 10 years loading; one tilted implant was lost at 10 years. Eight additional posterior implants were placed for either these lost tilted posterior implants or as proactive supplemental support; one of these replacement tilted implants survived for at least 10 years and is included in the data. All patients have maintained continuous fixed function throughout the follow-up period. Forty-one out of 44 patients continue with the original restoration, 33 without modification or removal of the fixed restoration or implant-connecting bar. One porcelain-to-gold and seven Marius Bridges had framework modifications to accommodate additional implants; 3 Marius Bridge restorations were replaced with a newer generation. Within the limits of this retrospective study, the results show that continuous fixed function of fully implant-supported maxillary restorations using posterior tilted implants in terminal positions of support as a sinus graft alternative combined with axial anterior implants is possible over a prolonged period. Loss of a posterior

  6. Psychological intervention following implantation of an implantable defibrillator

    Pedersen, Susanne S.; van den Broek, Krista C; Sears, Samuel F

    2007-01-01

    The medical benefits of the implantable cardioverter defibrillator (ICD) are unequivocal, but a subgroup of patients experiences emotional difficulties following implantation. For this subgroup, some form of psychological intervention may be warranted. This review provides an overview of current ...

  7. Comparison of Carina active middle-ear implant with conventional hearing aids for mixed hearing loss.

    Savaş, V A; Gündüz, B; Karamert, R; Cevizci, R; Düzlü, M; Tutar, H; Bayazit, Y A

    2016-04-01

    To compare the auditory outcomes of Carina middle-ear implants with those of conventional hearing aids in patients with moderate-to-severe mixed hearing loss. The study comprised nine patients (six males, three females) who underwent middle-ear implantation with Carina fully implantable active middle-ear implants to treat bilateral moderate-to-severe mixed hearing loss. The patients initially used conventional hearing aids and subsequently received the Carina implants. The hearing thresholds with implants and hearing aids were compared. There were no significant differences between: the pre-operative and post-operative air and bone conduction thresholds (p > 0.05), the thresholds with hearing aids and Carina implants (p > 0.05), or the pre-operative (mean, 72.8 ± 19 per cent) and post-operative (mean, 69.9 ± 24 per cent) speech discrimination scores (p > 0.05). One of the patients suffered total sensorineural hearing loss three months following implantation despite an initial 38 dB functional gain. All except one patient showed clinical improvements after implantation according to quality of life questionnaire (Glasgow Benefit Inventory) scores. Acceptance of Carina implants is better than with conventional hearing aids in patients with mixed hearing loss, although both yield similar hearing amplification. Cosmetic reasons appear to be critical for patient acceptance.

  8. Exploring the experiences of teenagers with cochlear implants.

    Watson, Victoria; Verschuur, Carl; Lathlean, Judith

    2016-11-01

    Teenage cochlear implant users' perceptions of deafness, surgery, fitting of the device and life as a cochlear implant wearer were explored in order to gain a more comprehensive understanding of teenagers' experiences of living with the device. Semi-structured in-depth interviews were undertaken and analysed using thematic analysis. Ten teenagers aged 14-16 years with at least one cochlear implant were interviewed. Seven teenagers experienced great pre-operative anxiety and two reported significant post-operative pain. Four of the teenagers described a mismatch between their expectations and the disappointing reality of adjusting to the device. However, all the teenagers reported an enhanced sense of well-being as a result of being able to interact more easily with their world around them. The teenagers differed in the extent to which they identified with the hearing and deaf world. Despite the early challenges, over time the teenagers experienced many functional and psychosocial benefits. Most felt their lives were now easier as a result of the cochlear implant(s). They described complex, flexible identities. By giving prominence to the teenagers' voices this study has added new knowledge concerning their experience of surgery. The findings also more fully revealed the challenges of adjusting to the device and the impact of having a cochlear implant on the teenagers' identities. Clinical recommendations are made to address the gaps in service highlighted by these findings.

  9. Management of peri-implantitis

    Jayachandran Prathapachandran

    2012-01-01

    Full Text Available Peri-implantitis is a site-specific infectious disease that causes an inflammatory process in soft tissues, and bone loss around an osseointegrated implant in function. The etiology of the implant infection is conditioned by the status of the tissue surrounding the implant, implant design, degree of roughness, external morphology, and excessive mechanical load. The microorganisms most commonly associated with implant failure are spirochetes and mobile forms of Gram-negative anaerobes, unless the origin is the result of simple mechanical overload. Diagnosis is based on changes of color in the gingiva, bleeding and probing depth of peri-implant pockets, suppuration, X-ray, and gradual loss of bone height around the tooth. Treatment will differ depending upon whether it is a case of peri-implant mucositis or peri-implantitis. The management of implant infection should be focused on the control of infection, the detoxification of the implant surface, and regeneration of the alveolar bone. This review article deals with the various treatment options in the management of peri-implantitis. The article also gives a brief description of the etiopathogenesis, clinical features, and diagnosis of peri-implantitis.

  10. Interaction of nitrogen with vacancy defects in N+-implanted ZnO studied using a slow positron beam

    Chen, Z.Q.; Maekawa, M.; Kawasuso, A.; Suzuki, R.; Ohdaira, T.

    2005-01-01

    ZnO crystals were implanted with N + , O + , and Al + , and co-implanted with O + /N + and Al + /N + ions. Positron annihilation measurements indicate introduction of vacancy clusters upon implantation. In the N + -implanted and Al + /N + co-implanted samples, these vacancy clusters are only partially annealed at 800 deg. C, as compared with their entire recovery in the O + - and Al + -implanted samples at 800-900 deg. C, suggesting a strong interaction between nitrogen and vacancy clusters. However, in the O + /N + co-implanted sample, most vacancy clusters disappear at 800 deg. C. Probably oxygen scavenges nitrogen to enhance the annealing of the vacancy clusters. Upon further annealing at 1000-1100 deg. C, nitrogen also forms stable complexes with thermally generated vacancies. These nitrogen-related vacancy complexes need high-temperature annealing at 1200-1250 deg. C to be fully removed

  11. Thermal desorption of deuterium implanted into beryllium

    Markin, A.V.; Chernikov, V.N.; Zakharov, A.P.

    1995-01-01

    By means of TDS measurements it is shown that the desorption of deuterium from Be implanted with 5 keV D ions to fluences, Φ, from 1x10 20 D/m 2 to 1x10 21 D/m 2 proceeds in one high temperature stage B, while at Φ ≥ 1.2x10 21 D/m 2 one more stage A is added. The desorption maximum A is narrow and consists of two peaks A 1 and A 2 at about 460 K and 490 K, respectively. Peak A 1 is attributed to the desorption of deuterium from the walls of opened channels formed under D ion implantation. Peak A 2 is a consequence of the opening of a part of closed bubbles/channels to the outer surface. The position of maximum B shifts noticeably and nonsteadily on the fluence in a range from 850 to 1050 K. The origin of this maximum is the liberation of D atoms bound at vacancy complexes discussed previously by Wampler. The dependence of Tm(B) on the fluence is governed by the interaction of freely migrating D atoms with partly opened or fully closed gas cavity arrangements which are created under temperature ramping, but differently in specimens implanted with D ions to different fluences

  12. Ion implantation control system

    Gault, R. B.; Keutzer, L. L.

    1985-01-01

    A control system is disclosed for an ion implantation system of the type in which the wafers to be implanted are mounted around the periphery of a disk which rotates and also moves in a radial direction relative to an ion beam to expose successive sections of each wafer to the radiation. The control system senses beam current which passes through one or more apertures in the disk and is collected by a Faraday cup. This current is integrated to obtain a measure of charge which is compared with a calculated value based upon the desired ion dosage and other parameters. The resultant controls the number of incremental steps the rotating disk moves radially to expose the adjacent sections of each wafer. This process is continued usually with two or more traverses until the entire surface of each wafer has been implanted with the proper ion dosage

  13. Implantation for tribological applications

    Leutenecker, R.; Cao-Minh, U.; Overbeck, R.

    1992-08-01

    Empirical results on the strength enhancement of steels by N- and B-implantation should be explained from a materials science point of view. The methods applied were X-ray diffractometry and element depth profiling. The investigations of N-implanted steels focussed on the nitride formation in selected model materials and, with respect to applications, in: X90 CrMoV and S 6-5-2 tool steels, austenite X10 CrNiTi189 as well as in hard chromium plates. Main topic in B-implanted steels were the transformations: crystalline Fe-phase - amorphous Fe-B-phase - crystalline boride phases. The result is an improvement in process control by first an insight into the strength enhancing mechanisms and second in into their generation depending on the materials microstructure and the process parameter. (orig.). 101 figs., 16 tabs., 15 refs [de

  14. Dental implants: A review.

    Guillaume, B

    2016-12-01

    A high number of patients have one or more missing tooth and it is estimated that one in four American subjects over the age of 74 have lost all their natural teeth. Many options exist to replace missing teeth but dental implants have become one of the most used biomaterial to replace one (or more) missing tooth over the last decades. Contemporary dental implants made with titanium have been proven safe and effective in large series of patients. This review considers the main historical facts concerned with dental implants and present the different critical factors that will ensure a good osseo-integration that will ensure a stable prosthesis anchorage. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. Tribology of implantation bilayers

    Pivin, J.C.

    1989-01-01

    The mechanical behaviour of implantation films must be analysed in terms of bilayer rheology (laws of mechanical behaviour). Tribology takes into account thermodynamical, chemical and metallurgical parameters to interpret the friction properties of a system as a whole. One can distinguish between alloying effects of ion implantation and structural modifications. Alloying affects the basic properties of the crystal: elasticity, cohesion, mobility of planar defects, and its surface electronic structure, which determines the reactivity with the atmosphere or the friction counterpart (adhesion). Radiation damage and phase changes act more particularly on the modes of gliding and climbing of dislocations, and fracture mechanisms. 105 refs.; 11 figs.; 1 table

  16. [Tinnitus and implants].

    Despreaux, G; Tison, P; Van Den Abbeele, T; Moine, A; Frachet, B

    1990-01-01

    The experience with cochlear implantation at Avicenne hospital prompted us to carry out a retrospective study on tinnitus in a population of operated patients. Improvement or disappearance of the symptoms was noted in all cases. These results, which partly match those found in the literature, are probably produced by rehabilitation inhibiting the "deafferentation" mechanisms in analogy with pain phenomena. In some precise cases, which are described, they led us to proposing implantation even though the main, if not sole, complaint of the patient was tinnitus.

  17. Engineering aspects of a fully mirrored endoscope

    Terra, A.; Huber, A.; Schweer, B.; Mertens, Ph.; Arnoux, G.; Balshaw, N.; Brezinsek, S.; Egner, S.; Hartl, M.; Kampf, D.; Klammer, J.; Lambertz, H.T.; Morlock, C.; Murari, A.; Reindl, M.; Sanders, S.; Sergienko, G.; Spencer, G.

    2013-01-01

    Highlights: ► Replacement of JET diagnostics to match the new ITER-like Wall. ► The endoscope test ITER-like design with only mirror based optics. ► Withstanding and diagnostic capability during Plasma operation and disruptions. ► Engineering process from design to installation and procurement. -- Abstract: The development of optical diagnostics, like endoscopes, compatible with the ITER environment (metallic plasma facing components, neutron proof optics, etc.) is a challenge, but current tokamaks such as JET provide opportunities to test fully working concepts. This paper describes the engineering aspects of a fully mirrored endoscope that has recently been designed, procured and installed on JET. The system must operate in a very strict environment with high temperature, high magnetic fields up to B = 4 T and rapid field variations (∂B/∂t ∼ 100 T/s) that induce high stresses due to eddy currents in the front mirror assembly. It must be designed to withstand high mechanical loads especially during disruptions, which lead to acceleration of about 7 g at 14 Hz. For the JET endoscope, when the plasma thermal loading, direct and indirect, was added to the assumed disruption loads, the reserve factor, defined as a ratio of yield strength over summed up von Mises stresses, was close to 1 for the mirror components. To ensure reliable operation, several analyses were performed to evaluate the thermo-mechanical performance of the endoscope and a final validation was obtained from mechanical and thermal tests, before the system's final installation in May 2011. During the tests, stability of the field of view angle variation was kept below 1° despite the high thermal gradient on endoscope head (∂T/∂x ∼ 500 K/m). In parallel, to ensure long time operation and to prevent undesirable performance degradation, a shutter system was also implemented in order to reduce impurity deposition on in-vessel mirrors but also to allow in situ transmission calibration

  18. Fully 3D refraction correction dosimetry system

    Manjappa, Rakesh; Makki, S Sharath; Kanhirodan, Rajan; Kumar, Rajesh; Vasu, Ram Mohan

    2016-01-01

    The irradiation of selective regions in a polymer gel dosimeter results in an increase in optical density and refractive index (RI) at those regions. An optical tomography-based dosimeter depends on rayline path through the dosimeter to estimate and reconstruct the dose distribution. The refraction of light passing through a dose region results in artefacts in the reconstructed images. These refraction errors are dependant on the scanning geometry and collection optics. We developed a fully 3D image reconstruction algorithm, algebraic reconstruction technique-refraction correction (ART-rc) that corrects for the refractive index mismatches present in a gel dosimeter scanner not only at the boundary, but also for any rayline refraction due to multiple dose regions inside the dosimeter. In this study, simulation and experimental studies have been carried out to reconstruct a 3D dose volume using 2D CCD measurements taken for various views. The study also focuses on the effectiveness of using different refractive-index matching media surrounding the gel dosimeter. Since the optical density is assumed to be low for a dosimeter, the filtered backprojection is routinely used for reconstruction. We carry out the reconstructions using conventional algebraic reconstruction (ART) and refractive index corrected ART (ART-rc) algorithms. The reconstructions based on FDK algorithm for cone-beam tomography has also been carried out for comparison. Line scanners and point detectors, are used to obtain reconstructions plane by plane. The rays passing through dose region with a RI mismatch does not reach the detector in the same plane depending on the angle of incidence and RI. In the fully 3D scanning setup using 2D array detectors, light rays that undergo refraction are still collected and hence can still be accounted for in the reconstruction algorithm. It is found that, for the central region of the dosimeter, the usable radius using ART-rc algorithm with water as RI matched

  19. Fully 3D refraction correction dosimetry system.

    Manjappa, Rakesh; Makki, S Sharath; Kumar, Rajesh; Vasu, Ram Mohan; Kanhirodan, Rajan

    2016-02-21

    The irradiation of selective regions in a polymer gel dosimeter results in an increase in optical density and refractive index (RI) at those regions. An optical tomography-based dosimeter depends on rayline path through the dosimeter to estimate and reconstruct the dose distribution. The refraction of light passing through a dose region results in artefacts in the reconstructed images. These refraction errors are dependant on the scanning geometry and collection optics. We developed a fully 3D image reconstruction algorithm, algebraic reconstruction technique-refraction correction (ART-rc) that corrects for the refractive index mismatches present in a gel dosimeter scanner not only at the boundary, but also for any rayline refraction due to multiple dose regions inside the dosimeter. In this study, simulation and experimental studies have been carried out to reconstruct a 3D dose volume using 2D CCD measurements taken for various views. The study also focuses on the effectiveness of using different refractive-index matching media surrounding the gel dosimeter. Since the optical density is assumed to be low for a dosimeter, the filtered backprojection is routinely used for reconstruction. We carry out the reconstructions using conventional algebraic reconstruction (ART) and refractive index corrected ART (ART-rc) algorithms. The reconstructions based on FDK algorithm for cone-beam tomography has also been carried out for comparison. Line scanners and point detectors, are used to obtain reconstructions plane by plane. The rays passing through dose region with a RI mismatch does not reach the detector in the same plane depending on the angle of incidence and RI. In the fully 3D scanning setup using 2D array detectors, light rays that undergo refraction are still collected and hence can still be accounted for in the reconstruction algorithm. It is found that, for the central region of the dosimeter, the usable radius using ART-rc algorithm with water as RI matched

  20. PVT Panels. Fully renewable and competitive

    Bakker, M.; Strootman, K.J.; Jong, M.J.M.

    2003-10-01

    A photovoltaic/thermal (PVT) panel is a combination of photovoltaic cells with a solar thermal collector, generating solar electricity and solar heat simultaneously. PVT panels generate more solar energy per unit surface area than a combination of separate PV panels and solar thermal collectors, and share the aesthetic advantage of PV. After several years of research, PVT panels have been developed into a product that is now ready for market introduction. One of the most promising system concepts, consisting of 25 m 2 of PVT panels and a ground coupled heat pump, has been simulated in TRNSYS, and has been found to be able to fully cover both the building related electricity and heat consumption, while keeping the long-term average ground temperature constant. The cost and payback time of such a system have been determined; it has been found that the payback time of this system is approximately two-thirds of the payback time of an identical system but with 21 m 2 of PV panels and 4 m 2 of solar thermal collectors. Finally, by looking at the expected growth in the PV and solar thermal collector market, the market potential for for PVT panels has been found to be very large

  1. A new fully automated TLD badge reader

    Kannan, S.; Ratna, P.; Kulkarni, M.S.

    2003-01-01

    At present personnel monitoring in India is being carried out using a number of manual and semiautomatic TLD badge Readers and the BARC TL dosimeter badge designed during 1970. Of late the manual TLD badge readers are almost completely replaced by semiautomatic readers with a number of performance improvements like use of hot gas heating to reduce the readout time considerably. PC based design with storage of glow curve for every dosimeter, on-line dose computation and printout of dose reports, etc. However the semiautomatic system suffers from the lack of a machine readable ID code on the badge and the physical design of the dosimeter card not readily compatible for automation. This paper describes a fully automated TLD badge Reader developed in the RSS Division, using a new TLD badge with machine readable ID code. The new PC based reader has a built-in reader for reading the ID code, in the form of an array of holes, on the dosimeter card. The reader has a number of self-diagnostic features to ensure a high degree of reliability. (author)

  2. Fully inkjet-printed microwave passive electronics

    McKerricher, Garret

    2017-01-30

    Fully inkjet-printed three-dimensional (3D) objects with integrated metal provide exciting possibilities for on-demand fabrication of radio frequency electronics such as inductors, capacitors, and filters. To date, there have been several reports of printed radio frequency components metallized via the use of plating solutions, sputtering, and low-conductivity pastes. These metallization techniques require rather complex fabrication, and do not provide an easily integrated or versatile process. This work utilizes a novel silver ink cured with a low-cost infrared lamp at only 80 °C, and achieves a high conductivity of 1×107 S m−1. By inkjet printing the infrared-cured silver together with a commercial 3D inkjet ultraviolet-cured acrylic dielectric, a multilayer process is demonstrated. By using a smoothing technique, both the conductive ink and dielectric provide surface roughness values of <500 nm. A radio frequency inductor and capacitor exhibit state-of-the-art quality factors of 8 and 20, respectively, and match well with electromagnetic simulations. These components are implemented in a lumped element radio frequency filter with an impressive insertion loss of 0.8 dB at 1 GHz, proving the utility of the process for sensitive radio frequency applications.

  3. The first LHC sector is fully interconnected

    2006-01-01

    Sector 7-8 is the first sector of the LHC to become fully operational. All the magnets, cryogenic line, vacuum chambers and services are interconnected. The cool down of this sector can soon commence. LHC project leader Lyn Evans, the teams from CERN's AT/MCS, AT/VAC and AT/MEL groups, and the members of the IEG consortium celebrate the completion of the first LHC sector. The 10th of November was a red letter day for the LHC accelerator teams, marking the completion of the first sector of the machine. The magnets of sector 7-8, together with the cryogenic line, the vacuum chambers and the distribution feedboxes (DFBs) are now all completely interconnected. Sector 7-8 has thus been closed and is the first LHC sector to become operational. The interconnection work required several thousand electrical, cryogenic and insulating connections to be made on the 210 interfaces between the magnets in the arc, the 30 interfaces between the special magnets and the interfaces with the cryogenic line. 'This represent...

  4. Fully Resolved Simulations of 3D Printing

    Tryggvason, Gretar; Xia, Huanxiong; Lu, Jiacai

    2017-11-01

    Numerical simulations of Fused Deposition Modeling (FDM) (or Fused Filament Fabrication) where a filament of hot, viscous polymer is deposited to ``print'' a three-dimensional object, layer by layer, are presented. A finite volume/front tracking method is used to follow the injection, cooling, solidification and shrinking of the filament. The injection of the hot melt is modeled using a volume source, combined with a nozzle, modeled as an immersed boundary, that follows a prescribed trajectory. The viscosity of the melt depends on the temperature and the shear rate and the polymer becomes immobile as its viscosity increases. As the polymer solidifies, the stress is found by assuming a hyperelastic constitutive equation. The method is described and its accuracy and convergence properties are tested by grid refinement studies for a simple setup involving two short filaments, one on top of the other. The effect of the various injection parameters, such as nozzle velocity and injection velocity are briefly examined and the applicability of the approach to simulate the construction of simple multilayer objects is shown. The role of fully resolved simulations for additive manufacturing and their use for novel processes and as the ``ground truth'' for reduced order models is discussed.

  5. Microaneurysm detection using fully convolutional neural networks.

    Chudzik, Piotr; Majumdar, Somshubra; Calivá, Francesco; Al-Diri, Bashir; Hunter, Andrew

    2018-05-01

    Diabetic retinopathy is a microvascular complication of diabetes that can lead to sight loss if treated not early enough. Microaneurysms are the earliest clinical signs of diabetic retinopathy. This paper presents an automatic method for detecting microaneurysms in fundus photographies. A novel patch-based fully convolutional neural network with batch normalization layers and Dice loss function is proposed. Compared to other methods that require up to five processing stages, it requires only three. Furthermore, to the best of the authors' knowledge, this is the first paper that shows how to successfully transfer knowledge between datasets in the microaneurysm detection domain. The proposed method was evaluated using three publicly available and widely used datasets: E-Ophtha, DIARETDB1, and ROC. It achieved better results than state-of-the-art methods using the FROC metric. The proposed algorithm accomplished highest sensitivities for low false positive rates, which is particularly important for screening purposes. Performance, simplicity, and robustness of the proposed method demonstrates its suitability for diabetic retinopathy screening applications. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Fully inkjet-printed microwave passive electronics

    McKerricher, Garret; Vaseem, Mohammad; Shamim, Atif

    2017-01-01

    Fully inkjet-printed three-dimensional (3D) objects with integrated metal provide exciting possibilities for on-demand fabrication of radio frequency electronics such as inductors, capacitors, and filters. To date, there have been several reports of printed radio frequency components metallized via the use of plating solutions, sputtering, and low-conductivity pastes. These metallization techniques require rather complex fabrication, and do not provide an easily integrated or versatile process. This work utilizes a novel silver ink cured with a low-cost infrared lamp at only 80 °C, and achieves a high conductivity of 1×107 S m−1. By inkjet printing the infrared-cured silver together with a commercial 3D inkjet ultraviolet-cured acrylic dielectric, a multilayer process is demonstrated. By using a smoothing technique, both the conductive ink and dielectric provide surface roughness values of <500 nm. A radio frequency inductor and capacitor exhibit state-of-the-art quality factors of 8 and 20, respectively, and match well with electromagnetic simulations. These components are implemented in a lumped element radio frequency filter with an impressive insertion loss of 0.8 dB at 1 GHz, proving the utility of the process for sensitive radio frequency applications.

  7. Cochlear implantation in autistic children with profound sensorineural hearing loss.

    Lachowska, Magdalena; Pastuszka, Agnieszka; Łukaszewicz-Moszyńska, Zuzanna; Mikołajewska, Lidia; Niemczyk, Kazimierz

    2016-11-19

    Cochlear implants have become the method of choice for the treatment of severe-to-profound hearing loss in both children and adults. Its benefits are well documented in the pediatric and adult population. Also deaf children with additional needs, including autism, have been covered by this treatment. The aim of this study was to assess the benefits from cochlear implantation in deafened children with autism as the only additional disability. This study analyzes data of six children. The follow-up time was at least 43 months. The following data were analyzed: medical history, reaction to music and sound, Ling's six sounds test, onomatopoeic word test, reaction to spoken child's name, response to requests, questionnaire given to parents, sound processor fitting sessions and data. After cochlear implantation each child presented other communication skills. In some children, the symptoms of speech understanding were observed. No increased hyperactivity associated with daily use cochlear implant was observed. The study showed that in autistic children the perception is very important for a child's sense of security and makes contact with parents easier. Our study showed that oral communication is not likely to be a realistic goal in children with cochlear implants and autism. The implantation results showed benefits that varied among those children. The traditional methods of evaluating the results of cochlear implantation in children with autism are usually insufficient to fully assess the functional benefits. These benefits should be assessed in a more comprehensive manner taking into account the limitations of communication resulting from the essence of autism. It is important that we share knowledge about these complex children with cochlear implants. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  8. Recent advances in dental implants.

    Hong, Do Gia Khang; Oh, Ji-Hyeon

    2017-12-01

    Dental implants are a common treatment for the loss of teeth. This paper summarizes current knowledge on implant surfaces, immediate loading versus conventional loading, short implants, sinus lifting, and custom implants using three-dimensional printing. Most of the implant surface modifications showed good osseointegration results. Regarding biomolecular coatings, which have been recently developed and studied, good results were observed in animal experiments. Immediate loading had similar clinical outcomes compared to conventional loading and can be used as a successful treatment because it has the advantage of reducing treatment times and providing early function and aesthetics. Short implants showed similar clinical outcomes compared to standard implants. A variety of sinus augmentation techniques, grafting materials, and alternative techniques, such as tilted implants, zygomatic implants, and short implants, can be used. With the development of new technologies in three-dimension and computer-aided design/computer-aided manufacturing (CAD/CAM) customized implants can be used as an alternative to conventional implant designs. However, there are limitations due to the lack of long-term studies or clinical studies. A long-term clinical trial and a more predictive study are needed.

  9. Untreated silicone breast implant rupture

    Hölmich, Lisbet R; Vejborg, Ilse M; Conrad, Carsten

    2004-01-01

    Implant rupture is a well-known complication of breast implant surgery that can pass unnoticed by both patient and physician. To date, no prospective study has addressed the possible health implications of silicone breast implant rupture. The aim of the present study was to evaluate whether untre...

  10. Treatment of Orally Handicapped Edentulous Older Adults Using Dental Implants.

    Zahedi, Charles

    2016-07-01

    The oral handicap of complete edentulism is the terminal outcome of a multifactorial process involving biological factors and patient-related factors. Fully edentulous orally handicapped older adults have been neglected because removable acrylic dentures have been the classic therapy for complete edentulism but are only rehabilitative, not therapeutic. Not replacing missing teeth with stable dentures could prevent adequate food intake. Osseointegrated endosseous implants used as a therapeutic adjunct can reduce the problem of long-term bone resorption to less than 0.1 mm per year. Implant-borne prostheses substantially increase the overall health and quality of life of orally handicapped fully edentulous older adults. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Piezosurgery applied to implant dentistry: clinical and biological aspects.

    Pereira, Cassiano Costa Silva; Gealh, Walter Cristiano; Meorin-Nogueira, Lamis; Garcia-Júnior, Idelmo Rangel; Okamoto, Roberta

    2014-07-01

    Piezosurgery is a new and modern technique of bone surgery in implantology. Selective cutting is possible for different ultrasonic frequencies acting only in hard tissues (mineralized), saving vital anatomical structures. With the piezoelectric osteotomy technique, receptor site preparation for implants, autogenous bone graft acquistition (particles and blocks), osteotomy for alveolar bone crest expansion, maxillary sinus lifting, and dental implant removal can be performed accurately and safely, providing excellent clinical and biological results, especially for osteocyte viability. The aim of this review was, through literature review, to present clinical applications of piezosurgery in implant dentistry and outline their advantages and disadvantages over conventional surgical systems. Moreover, this study addressed the biological aspects related to piezosurgery that differentiate it from those of bone tissue approaches. Overall, piezosurgery enables critical operations in simple and fully executable procedures; and effectively, areas that are difficult to access have less risk of soft tissue and neurovascular tissue damage via piezosurgery.

  12. Semiconductor Ion Implanters

    MacKinnon, Barry A.; Ruffell, John P.

    2011-01-01

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion! Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  13. Implantable enzyme amperometric biosensors.

    Kotanen, Christian N; Moussy, Francis Gabriel; Carrara, Sandro; Guiseppi-Elie, Anthony

    2012-05-15

    The implantable enzyme amperometric biosensor continues as the dominant in vivo format for the detection, monitoring and reporting of biochemical analytes related to a wide range of pathologies. Widely used in animal studies, there is increasing emphasis on their use in diabetes care and management, the management of trauma-associated hemorrhage and in critical care monitoring by intensivists in the ICU. These frontier opportunities demand continuous indwelling performance for up to several years, well in excess of the currently approved seven days. This review outlines the many challenges to successful deployment of chronically implantable amperometric enzyme biosensors and emphasizes the emerging technological approaches in their continued development. The foreign body response plays a prominent role in implantable biotransducer failure. Topics considering the approaches to mitigate the inflammatory response, use of biomimetic chemistries, nanostructured topographies, drug eluting constructs, and tissue-to-device interface modulus matching are reviewed. Similarly, factors that influence biotransducer performance such as enzyme stability, substrate interference, mediator selection and calibration are reviewed. For the biosensor system, the opportunities and challenges of integration, guided by footprint requirements, the limitations of mixed signal electronics, and power requirements, has produced three systems approaches. The potential is great. However, integration along the multiple length scales needed to address fundamental issues and integration across the diverse disciplines needed to achieve success of these highly integrated systems, continues to be a challenge in the development and deployment of implantable amperometric enzyme biosensor systems. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. HA-Coated Implant

    Daugaard, Henrik; Søballe, Kjeld; Bechtold, Joan E

    2014-01-01

    of improving the fixation of implants. Of these, hydroxyapatite (HA) is the most widely used and most extensively investigated. HA is highly osseoconductive, and the positive effect is well documented in both basic and long-term clinical research [1–6]. This chapter describes experimental and clinical studies...

  15. Middle ear implants

    K S Gangadhara Somayaji

    2013-01-01

    Full Text Available Hearing loss is becoming more common in the society living in cities with lot of background noise around, and frequent use of gadgets like mobile phones, MP3s, and IPods are adding to the problem. The loss may involve the conductive or perceptive pathway. Majority of the patients with conductive hearing loss will revert back to normal hearing levels with medical and/or surgical treatment. However, in sensorineural hearing loss, many factors are involved in the management. Though traditionally hearing aids in various forms are the most commonly used modality in managing these patients, there are some drawbacks associated with them. Implantable middle ear amplifiers represent the most recent breakthrough in the management of hearing loss. Middle ear implants are surgically implanted electronic devices that aim to correct hearing loss by stimulating the ossicular chain or middle ear. Of late, they are also being used in the management of congenital conductive hearing loss and certain cases of chronic otitis media with residual hearing loss. The article aims to provide general information about the technology, indications and contraindications, selection of candidates, available systems, and advantages of middle ear implants. (MEI

  16. Delayed breast implant reconstruction

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne

    2011-01-01

    the period 1999 to 2006; 239 one-stage procedures and 353 two-stage procedures. The postoperative course through November 2009 was evaluated by cumulative incidence adjusting for competing risks for the selected outcomes; hematoma, infection, seroma, implant rupture, severe capsular contracture (modified...

  17. Remote actuated valve implant

    McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

    2014-02-25

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  18. Highly efficient fully transparent inverted OLEDs

    Meyer, J.; Winkler, T.; Hamwi, S.; Schmale, S.; Kröger, M.; Görrn, P.; Johannes, H.-H.; Riedl, T.; Lang, E.; Becker, D.; Dobbertin, T.; Kowalsky, W.

    2007-09-01

    One of the unique selling propositions of OLEDs is their potential to realize highly transparent devices over the visible spectrum. This is because organic semiconductors provide a large Stokes-Shift and low intrinsic absorption losses. Hence, new areas of applications for displays and ambient lighting become accessible, for instance, the integration of OLEDs into the windshield or the ceiling of automobiles. The main challenge in the realization of fully transparent devices is the deposition of the top electrode. ITO is commonly used as transparent bottom anode in a conventional OLED. To obtain uniform light emission over the entire viewing angle and a low series resistance, a TCO such as ITO is desirable as top contact as well. However, sputter deposition of ITO on top of organic layers causes damage induced by high energetic particles and UV radiation. We have found an efficient process to protect the organic layers against the ITO rf magnetron deposition process of ITO for an inverted OLED (IOLED). The inverted structure allows the integration of OLEDs in more powerful n-channel transistors used in active matrix backplanes. Employing the green electrophosphorescent material Ir(ppy) 3 lead to IOLED with a current efficiency of 50 cd/A and power efficiency of 24 lm/W at 100 cd/m2. The average transmittance exceeds 80 % in the visible region. The on-set voltage for light emission is lower than 3 V. In addition, by vertical stacking we achieved a very high current efficiency of more than 70 cd/A for transparent IOLED.

  19. Towards a Fully Conservative Water Balance

    Rodriguez, L. B.; Vionnet, C. A.; Younger, P. L.; Parkin, G.

    2001-12-01

    Hydrological modeling is nowadays an essential tool in many aspects of water resources assessment and management. For practical purposes, hydrological models may be defined as mathematical procedures, which transform meteorological input data such as precipitation and evapotranspiration into hydrological output values such as riverflows. Conceptual water balance models are one kind of hydrological models still quite popular among engineers and scientists for three main reasons: firstly the "book-keeping" procedure they are based upon makes them computationally inexpensive, secondly, they require far less data than any physically based model, and thirdly, once calibrated and validated, they can yield the proper order of magnitude of the water cycle component on the basin under investigation. A common criticism of water balance models is their lack of sound theoretical basis. In this work a fully conservative water balance model for basin applications which takes into account physical processes is presented. The two-storage level model contains four calibration parameters: a, b, l and Umax. The saturated storage component resembles the abcd model by Thomas, corrected by the presence of the aquifer storativity coefficient s and the river-aquifer interface conductance l. The resulting model is capable of estimating monthly basin-average of actual evapotranspiration, soil moisture, effective groundwater recharge, groundwater level fluctuations, baseflows and direct runoff using an integral form of the mass conservation law in the saturated/unsaturated layers. The model was applied to a 600 Km2 catchment in the United Kingdom. An eight-year record was used for calibration, while a similar record was reserved for validation of model results. Total streamflows as well as baseflows calculated by the model were compared with observed and estimated data. A quite good agreement was obtained. Finally, simulated groundwater levels were compared with observation data collected at

  20. 7 CFR 718.304 - Failure to fully comply.

    2010-01-01

    ... authorized in accordance with § 718.305 if the participant made a good faith effort to comply fully with the... FSA approval official to have made a good faith effort to comply fully with the terms and conditions...

  1. Towards a Scalable Fully-Implicit Fully-coupled Resistive MHD Formulation with Stabilized FE Methods

    Shadid, J N; Pawlowski, R P; Banks, J W; Chacon, L; Lin, P T; Tuminaro, R S

    2009-06-03

    This paper presents an initial study that is intended to explore the development of a scalable fully-implicit stabilized unstructured finite element (FE) capability for low-Mach-number resistive MHD. The discussion considers the development of the stabilized FE formulation and the underlying fully-coupled preconditioned Newton-Krylov nonlinear iterative solver. To enable robust, scalable and efficient solution of the large-scale sparse linear systems generated by the Newton linearization, fully-coupled algebraic multilevel preconditioners are employed. Verification results demonstrate the expected order-of-acuracy for the stabilized FE discretization of a 2D vector potential form for the steady and transient solution of the resistive MHD system. In addition, this study puts forth a set of challenging prototype problems that include the solution of an MHD Faraday conduction pump, a hydromagnetic Rayleigh-Bernard linear stability calculation, and a magnetic island coalescence problem. Initial results that explore the scaling of the solution methods are presented on up to 4096 processors for problems with up to 64M unknowns on a CrayXT3/4. Additionally, a large-scale proof-of-capability calculation for 1 billion unknowns for the MHD Faraday pump problem on 24,000 cores is presented.

  2. Improved oxidation resistance of group VB refractory metals by Al+ ion implantation

    Hampikian, J.M.

    1996-01-01

    Aluminum ion implantation of vanadium, niobium, and tantalum improved the metals' oxidation resistances at 500 C and 735 C. Implanted vanadium oxidized only to one-third the extent of unimplanted vanadium when exposed at 500 C to air. The oxidative weight gains of implanted niobium and tantalum proved negligible when measured at 500 C and for times sufficient to fully convert the untreated metals to their pentoxides. At 735 C, implantation of vanadium only slightly retarded its oxidation, while oxidative weight gains of niobium and tantalum were reduced by factors of 3 or more. Implanted niobium exhibited weight gain in direct proportion to oxidation time squared at 735 C. Microstructural examination of the metals implanted with selected fluences of the 180 kV aluminum ions showed the following. The solubility limit of aluminum is extended by implantation, the body centered cubic (bcc) phases being retained to ∼60 at. pct Al in all three metals. The highest fluence investigated, 2.4 x 10 22 ions/m 2 , produced an ∼400-nm layer of VAl 3 beneath the surface of vanadium, and ∼300-nm layers of an amorphous phase containing ∼70 at. pct Al beneath the niobium and tantalum surfaces. All three metals, implanted to this fluence and annealed at 600 C, contained tri-aluminides, intermetallic compounds known for their oxidation resistances. Specimens implanted to this fluence were thus selected for the oxidation measurements

  3. Contemporary guided bone regeneration therapy for unaesthetic anterior peri-implantitis case

    Benso Sulijaya

    2016-12-01

    Full Text Available Background: Dental implant is one of an alternative solutions reconstruction therapy for missing teeth. Complication of dental implant could occurs and leading to implant failure. In order to restore the complication, surgical treatment with guided bone regeneration (GBR is indicated. The potential use of bone substitutes is widely known to be able to regenerate the bone surrounding the implant and maintain bone volume. Purpose: The study aimed to demonstrate the effectiveness of implant-bone fully coverage by using sandwich technique of biphasic calcium phosphate (BCP and demineralized freeze-dried bone allografts (DFDBA bone substitutes combined with collagen resorbable membrane. Case: A 24-year-old male came with diagnosis of peri-implantitis on implant #11. Clinical finding indicated that implant thread was exposed on the labial aspect. Case management: After initial therapy including oral hygiene improvement performed, an operator did a contemporary GBR to correct the defect. Bone graft materials used were 40% β-tri calcium phosphate (β-TCP-60% hydroxyapatite (HA on the outer layer and DFDBA on the inner layer of the defect. Resorbable collagen membrane was used to cover the graft. Conclusion: GBR with sandwich technique could serve as one of the treatment choices for correcting an exposed anterior implant that would enhance the successful aesthetic outcome.

  4. In vivo evaluation of mastication noise reduction for dual channel implantable microphone.

    Woo, SeongTak; Jung, EuiSung; Lim, HyungGyu; Lee, Jang Woo; Seong, Ki Woong; Won, Chul Ho; Kim, Myoung Nam; Cho, Jin Ho; Lee, Jyung Hyun

    2014-01-01

    Input for fully implantable hearing devices (FIHDs) is provided by an implantable microphone under the skin of the temporal bone. However, the implanted microphone can be affected when the FIHDs user chews. In this paper, a dual implantable microphone was designed that can filter out the noise from mastication. For the in vivo experiment, a fabricated microphone was implanted in a rabbit. Pure-tone sounds of 1 kHz through a standard speaker were applied to the rabbit, which was given food simultaneously. To evaluate noise reduction, the measured signals were processed using a MATLAB program based adaptive filter. To verify the proposed method, the correlation coefficients and signal to-noise ratio before and after signal processing were calculated. By comparing the results, signal-to-noise ratio and correlation coefficients are enhanced by 6.07dB and 0.529 respectively.

  5. New approach to solve symmetric fully fuzzy linear systems

    concepts of fuzzy set theory and then define a fully fuzzy linear system of equations. .... To represent the above problem as fully fuzzy linear system, we represent x .... Fully fuzzy linear systems can be solved by Linear programming approach, ...

  6. Does platform switching really prevent crestal bone loss around implants?

    Yoshiyuki Hagiwara

    2010-08-01

    Full Text Available To maintain long-term implant stability, it is important to minimize bone loss around the implant. Several clinical studies have shown a mean marginal bone loss around dental implants of 1.5–2 mm in the first year after prosthetic restoration. Currently, concepts to prevent bone loss around dental implants have been reported as the platform switching (PLS. This technique use of prosthetic abutments with reduced width in relation to the implant platform diameter seems to have the greatest potential to limit the crestal resorption. However, there are only a few reports on the mechanism of action or the extent of bone loss prevention, and as such, it is difficult to say that the effect of PLS has been thoroughly examined. Excluding case reports, articles on PLS can be broadly categorized into: (1 radiographic evaluation of crestal bone level in humans, (2 histological and histomorphometrical analysis in animals, or (3 finite element analysis. This review revealed a shortage of published data for above three categories related PLS. Researchers have attempted to explain the mechanism of action of PLS; however, it is necessary to conduct further studies, including histological studies using animals, to clarify the mechanism fully.

  7. Efter cochlear implant

    Højen, Anders

    Dit barn har netop fået et cochlear implant. Hvad nu? Skal barnet fokusere udelukkende på at lære talt sprog, eller skal det også lære/fortsætte med tegnsprog eller støttetegn? Det er et vanskeligt spørgsmål, og før valget foretages, er det vigtigt at vurdere hvilke konsekvenser valget har, dels...... for den sproglige udvikling isoleret set, og dels for barnets udvikling ud fra en helhedsbetragtning. Dette indlæg fokuserer på, hvilke forventninger man kan have til cochlear implant-brugeres sproglige udvikling med talt sprog alene, hhv. med to sprog (tale og tegn). Disse forventninger er baseret på...

  8. Delayed breast implant reconstruction

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne

    2012-01-01

    We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast...... reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy....

  9. Piezosurgery in implant dentistry

    Stübinger, Stefan; Stricker, Andres; Berg, Britt-Isabelle

    2015-01-01

    Piezosurgery, or the use of piezoelectric devices, is being applied increasingly in oral and maxillofacial surgery. The main advantages of this technique are precise and selective cuttings, the avoidance of thermal damage, and the preservation of soft-tissue structures. Through the application of piezoelectric surgery, implant-site preparation, bone grafting, sinus-floor elevation, edentulous ridge splitting or the lateralization of the inferior alveolar nerve are very technically feasible. This clinical overview gives a short summary of the current literature and outlines the advantages and disadvantages of piezoelectric bone surgery in implant dentistry. Overall, piezoelectric surgery is superior to other methods that utilize mechanical instruments. Handling of delicate or compromised hard- and soft-tissue conditions can be performed with less risk for the patient. With respect to current and future innovative surgical concepts, piezoelectric surgery offers a wide range of new possibilities to perform customized and minimally invasive osteotomies. PMID:26635486

  10. Ion implantation in metals

    Vook, F.L.

    1977-02-01

    The application of ion beams to metals is rapidly emerging as a promising area of research and technology. This report briefly describes some of the recent advances in the modification and study of the basic properties of metals by ion implantation techniques. Most of the research discussed illustrates some of the new and exciting applications of ion beams to metals which are under active investigation at Sandia Laboratories, Albuquerque

  11. Modelling dental implant extraction by pullout and torque procedures.

    Rittel, D; Dorogoy, A; Shemtov-Yona, K

    2017-07-01

    Dental implants extraction, achieved either by applying torque or pullout force, is used to estimate the bone-implant interfacial strength. A detailed description of the mechanical and physical aspects of the extraction process in the literature is still missing. This paper presents 3D nonlinear dynamic finite element simulations of a commercial implant extraction process from the mandible bone. Emphasis is put on the typical load-displacement and torque-angle relationships for various types of cortical and trabecular bone strengths. The simulations also study of the influence of the osseointegration level on those relationships. This is done by simulating implant extraction right after insertion when interfacial frictional contact exists between the implant and bone, and long after insertion, assuming that the implant is fully bonded to the bone. The model does not include a separate representation and model of the interfacial layer for which available data is limited. The obtained relationships show that the higher the strength of the trabecular bone the higher the peak extraction force, while for application of torque, it is the cortical bone which might dictate the peak torque value. Information on the relative strength contrast of the cortical and trabecular components, as well as the progressive nature of the damage evolution, can be revealed from the obtained relations. It is shown that full osseointegration might multiply the peak and average load values by a factor 3-12 although the calculated work of extraction varies only by a factor of 1.5. From a quantitative point of view, it is suggested that, as an alternative to reporting peak load or torque values, an average value derived from the extraction work be used to better characterize the bone-implant interfacial strength. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. The breast implant controversy.

    Cook, R R; Harrison, M C; LeVier, R R

    1994-02-01

    The breast implant issue is a "bad news/good news" story. For many women with implants, the controversy has caused a fair degree of anxiety which may or may not be resolved as further information becomes available. It has also taken its toll on Dow Corning. Whole lines of medical products have been eliminated or are being phase out. The development of new medical applications has been terminated. As a consequence, employees have lost their jobs. What the effect will be on the biomedical industry as a whole remains to be seen (11). While silicones have been an important component in various medical devices, it is likely that other materials can be used as replacements. However, suppliers of non-silicone materials are also reevaluating their role in this market. For example, Du Pont, the nation's largest chemical company, has determined that the unpredictable and excessive costs of doing business with manufacturers of implantable medical devices no longer justifies the unrestricted sale of standard raw materials into this industry. Other companies are quietly following suit. On the up side, it is possible that the research being driven by this controversy will result in a greater understanding of the immunologic implications of xenobiotics, of the importance of nonbiased observations, of the need for ready access to valid data sets, and of the opportunity for valid scientific information to guide legal decisions. Only time will tell.

  13. Cochlear implants in children implanted in Jordan: A parental overview.

    Alkhamra, Rana A

    2015-07-01

    Exploring the perspective of parents on the cochlear implant process in Jordan. Sixty parents of deaf children were surveyed on the information gathering process prior to cochlear implant surgery, and their implant outcome expectations post-surgery. Whether child or parent characteristics may impact parents' post-surgical expectations was explored. Although parents used a variety of information sources when considering a cochlear implant, the ear, nose and throat doctor comprised their major source of information (60%). Parents received a range of information prior to cochlear implant but agreed (93.3%) on the need for a multidisciplinary team approach. Post-surgically, parents' expected major developments in the areas of spoken language (97%), and auditory skills (100%). Receiving education in mainstream schools (92%) was expected too. Parents perceived the cochlear implant decision as the best decision they can make for their child (98.3%). A significant correlation was found between parents contentment with the cochlear implant decision and expecting developments in the area of reading and writing (r=0.7). Child's age at implantation and age at hearing loss diagnosis significantly affected parents' post-implant outcome expectations (pparents agree on the need for a comprehensive multidisciplinary team approach during the different stages of the cochlear implant process. Parents' education about cochlear implants prior to the surgery can affect their post-surgical outcome expectations. The parental perspective presented in this study can help professionals develop better understanding of parents' needs and expectations and henceforth improve their services and support during the different stages of the cochlear implant process. Copyright © 2015. Published by Elsevier Ireland Ltd.

  14. Sub-meninges implantation reduces immune response to neural implants.

    Markwardt, Neil T; Stokol, Jodi; Rennaker, Robert L

    2013-04-15

    Glial scar formation around neural interfaces inhibits their ability to acquire usable signals from the surrounding neurons. To improve neural recording performance, the inflammatory response and glial scarring must be minimized. Previous work has indicated that meningeally derived cells participate in the immune response, and it is possible that the meninges may grow down around the shank of a neural implant, contributing to the formation of the glial scar. This study examines whether the glial scar can be reduced by placing a neural probe completely below the meninges. Rats were implanted with sets of loose microwire implants placed either completely below the meninges or implanted conventionally with the upper end penetrating the meninges, but not attached to the skull. Histological analysis was performed 4 weeks following surgical implantation to evaluate the glial scar. Our results found that sub-meninges implants showed an average reduction in reactive astrocyte activity of 63% compared to trans-meninges implants. Microglial activity was also reduced for sub-meninges implants. These results suggest that techniques that isolate implants from the meninges offer the potential to reduce the encapsulation response which should improve chronic recording quality and stability. Published by Elsevier B.V.

  15. Heat generated by dental implant drills during osteotomy-a review: heat generated by dental implant drills.

    Mishra, Sunil Kumar; Chowdhary, Ramesh

    2014-06-01

    Osseointegration is the more stable situation and results in a high success rate of dental implants. Heat generation during rotary cutting is one of the important factors influencing the development of osseointegration. To assess the various factors related to implant drills responsible for heat generation during osteotomy. To identify suitable literature, an electronic search was performed using Medline and Pubmed database. Articles published in between 1960 to February 2013 were searched. The search is focused on heat generated by dental implant drills during osteotomy. Various factors related to implant drill such effect of number of blades; drill design, drill fatigue, drill speed and force applied during osteotomies which were responsible for heat generation were reviewed. Titles and abstracts were screened, and literature that fulfilled the inclusion criteria was selected for a full-text reading. The initial literature search resulted in 299 articles out of which only 70 articles fulfils the inclusion criteria and were included in this systematic review. Many factors related to implant drill responsible for heat generation were found. Successful preparation of an implant cavity with minimal damage to the surrounding bone depends on the avoidance of excessive temperature generation during surgical drilling. The relationship between heat generated and implant drilling osteotomy is multifactorial in nature and its complexity has not been fully studied. Lack of scientific knowledge regarding this issue still exists. Further studies should be conducted to determine the various factors which generate less heat while osteotomy such as ideal ratio of force and speed in vivo, exact time to replace a drill, ideal drill design, irrigation system, drill-bone contact area.

  16. Improving osseointegration of dental implants.

    Elias, Carlos Nelson; Meirelles, Luiz

    2010-03-01

    In the beginning of implantology, the procedures adopted for treating patients were performed in two surgical phases with an interval of 3-6 months. Nowadays, it is possible to insert and load a dental implant in the same surgical procedure. This change is due to several factors, such as improvement of surgical technique, modifications of the implant design, increased quality of implant manufacturing, development of the surgical instruments' quality, careful patient screening and adequate treatment of the implant surface. The clinical results show that adequate treatment of surfaces is crucial for reducing healing time and treating at-risk patients. The surface properties of dental implants can be significantly improved at the manufacturing stage, affecting cells' activity during the healing phase that will ultimately determine the host tissue response, a fundamental requirement for clinical success. This review focuses on different types of dental implant surfaces and the influence of surface characteristics on osseointegration.

  17. Wide-diameter locking-taper implants: a prospective clinical study with 1 to 10-year follow-up

    C. Mangano

    2014-06-01

    Full Text Available Aim: Wide-diameter implants (WDIs, diameter ≥4.5 mm are increasingly being used in patients with poor bone quality and reduced bone height. The aim of this study was to evaluate the survival rate, peri-implant bone loss, biological and prosthetic complications of wide-diameter (4.8 mm locking-taper implants used in the restoration of partially and fully edentulous patients. Materials and methods: Between January 2002 and December 2011, all patients referred to a private clinic for treatment with WDIs were considered for inclusion in the study. At each annual follow-up session, clinical and radiographic parameters were assessed: the outcome measurements were implant failure, peri-implant bone loss (distance between the implant shoulder and the first visible bone-to-implant contact: DIB, biological and prosthetic complications. The cumulative survival rate (CSR was assessed using the Kaplan-Meier estimator; Log-rank was applied to evaluate correlations between the study variables. The statistical analysis was performed at the patient and at the implant level. Results: A total of 438 WDIs were placed in 411 patients. Four implants failed, for a CSR of 99% (patient-based and 99.1% (implant-based at 10-year follow-up. The CSR did not differ significantly with respect to patients’ gender, age, smoking or parafunctional habit, implant location, position, length, bone type or prosthetic restoration. A mean DIB of 0.34 mm (± 0.23, 0.45 mm (± 0.27 and 0.75 mm (± 0.33 was shown at the 1-, 5- and 10-year follow-up examination. Conclusions: Wide-diameter, locking-taper implants can be a good treatment option for the rehabilitation of partially and fully edentulous patients over the long term.

  18. Immediate Direct-To-Implant Breast Reconstruction Using Anatomical Implants

    Sung-Eun Kim

    2014-09-01

    Full Text Available BackgroundIn 2012, a new anatomic breast implant of form-stable silicone gel was introduced onto the Korean market. The intended use of this implant is in the area of aesthetic breast surgery, and many reports are promising. Thus far, however, there have been no reports on the use of this implant for breast reconstruction in Korea. We used this breast implant in breast reconstruction surgery and report our early experience.MethodsFrom November 2012 to April 2013, the Natrelle Style 410 form-stable anatomically shaped cohesive silicone gel-filled breast implant was used in 31 breasts of 30 patients for implant breast reconstruction with an acellular dermal matrix. Patients were treated with skin-sparing mastectomies followed by immediate breast reconstruction.ResultsThe mean breast resection volume was 240 mL (range, 83-540 mL. The mean size of the breast implants was 217 mL (range, 125-395 mL. Breast shape outcomes were considered acceptable. Infection and skin thinning occurred in one patient each, and hematoma and seroma did not occur. Three cases of wound dehiscence occurred, one requiring surgical intervention, while the others healed with conservative treatment in one month. Rippling did not occur. So far, complications such as capsular contracture and malrotation of breast implant have not yet arisen.ConclusionsBy using anatomic breast implants in breast reconstruction, we achieved satisfactory results with aesthetics better than those obtained with round breast implants. Therefore, we concluded that the anatomical implant is suitable for breast reconstruction.

  19. Dental implants in growing children

    S K Mishra

    2013-01-01

    Full Text Available The replacement of teeth by implants is usually restricted to patients with completed craniofacial growth. The aim of this literature review is to discuss the use of dental implants in normal growing patients and in patients with ectodermal dysplasia and the influence of maxillary and mandibular skeletal and dental growth on the stability of those implants. It is recommended that while deciding the optimal individual time point of implant insertion, the status of skeletal growth, the degree of hypodontia, and extension of related psychological stress should be taken into account, in addition to the status of existing dentition and dental compliance of a pediatric patient.

  20. Printing of Titanium implant prototype

    Wiria, Florencia Edith; Shyan, John Yong Ming; Lim, Poon Nian; Wen, Francis Goh Chung; Yeo, Jin Fei; Cao, Tong

    2010-01-01

    Dental implant plays an important role as a conduit of force and stress to flow from the tooth to the related bone. In the load sharing between an implant and its related bone, the amount of stress carried by each of them directly related to their stiffness or modulus. Hence, it is a crucial issue for the implant to have matching mechanical properties, in particular modulus, between the implant and its related bone. Titanium is a metallic material that has good biocompatibility and corrosion resistance. Whilst the modulus of the bulk material is still higher than that of bone, it is the lowest among all other commonly used metallic implant materials, such as stainless steel or cobalt alloy. Hence it is potential to further reduce the modulus of pure Titanium by engineering its processing method to obtain porous structure. In this project, porous Titanium implant prototype is fabricated using 3-dimensional printing. This technique allows the flexibility of design customization, which is beneficial for implant fabrication as tailoring of implant size and shape helps to ensure the implant would fit nicely to the patient. The fabricated Titanium prototype had a modulus of 4.8-13.2 GPa, which is in the range of natural bone modulus. The compressive strength achieved was between 167 to 455 MPa. Subsequent cell culture study indicated that the porous Titanium prototype had good biocompatibility and is suitable for bone cell attachment and proliferation.

  1. Cochlear implantation in Mondini dysplasia.

    Daneshi, Ahmad; Hassanzadeh, Saeid; Abasalipour, Parvaneh; Emamdjomeh, Hessamaddin; Farhadi, Mohammad

    2003-01-01

    The use of cochlear implantation to treat patients with inner ear malformations such as Mondini dysplasia has been increasingly successful. Until now, conventional hearing aids in these patients have not performed well. Consequently, the hearing problem for patients with this condition has been somewhat improved with the use of cochlear implants. Various results of cochlear implantation have been reported in these patients so far. This is a report of 5 patients with Mondini malformation who have undergone cochlear implant surgery. Copyright 2003 S. Karger AG, Basel

  2. Implant-retained maxillary overdentures.

    Eckert, Steven E; Carr, Alan B

    2004-07-01

    Overdentures supported by osseointegrated implants overcome many of the complications observed with overdentures supported by natural teeth. Dental implants are free of biologic consequences associated with natural teeth, such as dental caries and periodontal disease. Bone undercuts adjacent to implants do not mimic those found adjacent to natural tooth roots. Implants are used to provide predictable retention, support, and stability for overdenture prostheses. When lip or facial support is required, the overdenture is the treatment of choice. Likewise the overdenture may improve phonetic deficiencies associated with alveolar bone loss.

  3. Cochlear implants in Waardenburg syndrome.

    Cullen, Robert D; Zdanski, Carlton; Roush, Patricia; Brown, Carolyn; Teagle, Holly; Pillsbury, Harold C; Buchman, Craig

    2006-07-01

    Waardenburg syndrome is an autosomal-dominant syndrome characterized by dystopia canthorum, hyperplasia of the eyebrows, heterochromia irides, a white forelock, and sensorineural hearing loss in 20% to 55% of patients. This patient population accounts for approximately 2% of congenitally deaf children. The purpose of this retrospective case review was to describe the outcomes for those children with Waardenburg syndrome who have undergone cochlear implantation. Pediatric cochlear implant recipients with documented evidence of Waardenburg syndrome underwent retrospective case review. All patients received their cochlear implants at the study institution followed by outpatient auditory habilitation. Charts were reviewed for etiology and duration of deafness, age at time of cochlear implantation, perioperative complications, duration of use, and performance outcomes. Results of standard tests batteries for speech perception and production administered as a part of the patients' auditory habilitation were reviewed. Seven patients with Waardenburg syndrome and cochlear implants were identified. The average age at implantation was 37 months (range, 18-64 months) and the average duration of use was 69 months (range, 12-143 months). All of these patients are active users of their devices and perform very well after implantation. There were no major complications in this small group of patients. Children with congenital sensorineural hearing loss without other comorbidities (e.g., developmental delay, inner ear malformations) perform well when they receive cochlear implantation and auditory habilitation. Patients with Waardenburg syndrome can be expected to have above-average performance after cochlear implantation.

  4. Qualitative evaluation of titanium implant integration into bone by diffraction enhanced imaging

    Wagner, A; Sachse, A; Keller, M; Aurich, M; Wetzel, W-D; Hortschansky, P; Schmuck, K; Lohmann, M; Reime, B; Metge, J; Arfelli, F; Menk, R; Rigon, L; Muehleman, C; Bravin, A; Coan, P; Mollenhauer, J

    2006-01-01

    Diffraction enhanced imaging (DEI) uses refraction of x-rays at edges, which allows pronounced visualization of material borders and rejects scattering which often obscures edges and blurs images. Here, the first evidence is presented that, using DEI, a destruction-free evaluation of the quality of integration of metal implants into bone is possible. Experiments were performed in rabbits and sheep with model implants to investigate the option for DEI as a tool in implant research. The results obtained from DEI were compared to conventional histology obtained from the specimens. DE images allow the identification of the quality of ingrowth of bone into the hydroxyapatite layer of the implant. Incomplete integration of the implant with a remaining gap of less than 0.3 mm caused the presence of a highly refractive edge at the implant/bone border. In contrast, implants with bone fully grown onto the surface did not display a refractive signal. Therefore, the refractive signal could be utilized to diagnose implant healing and/or loosening

  5. Qualitative evaluation of titanium implant integration into bone by diffraction enhanced imaging

    Wagner, A.; Sachse, A.; Keller, M.; Aurich, M.; Wetzel, W.-D.; Hortschansky, P.; Schmuck, K.; Lohmann, M.; Reime, B.; Metge, J.; Arfelli, F.; Menk, R.; Rigon, L.; Muehleman, C.; Bravin, A.; Coan, P.; Mollenhauer, J.

    2006-03-01

    Diffraction enhanced imaging (DEI) uses refraction of x-rays at edges, which allows pronounced visualization of material borders and rejects scattering which often obscures edges and blurs images. Here, the first evidence is presented that, using DEI, a destruction-free evaluation of the quality of integration of metal implants into bone is possible. Experiments were performed in rabbits and sheep with model implants to investigate the option for DEI as a tool in implant research. The results obtained from DEI were compared to conventional histology obtained from the specimens. DE images allow the identification of the quality of ingrowth of bone into the hydroxyapatite layer of the implant. Incomplete integration of the implant with a remaining gap of less than 0.3 mm caused the presence of a highly refractive edge at the implant/bone border. In contrast, implants with bone fully grown onto the surface did not display a refractive signal. Therefore, the refractive signal could be utilized to diagnose implant healing and/or loosening.

  6. Modification of anti-bacterial surface properties of textile polymers by vacuum arc ion source implantation

    Nikolaev, A.G.; Yushkov, G.Yu.; Oks, E.M.; Oztarhan, A.; Akpek, A.; Hames-Kocabas, E.; Urkac, E.S.; Brown, I.G.

    2014-01-01

    Highlights: • Ion implantation. • Anti-bacterial properties. • Textile polymer. • Vacuum arc ion source. - Abstract: Ion implantation provides an important technology for the modification of material surface properties. The vacuum arc ion source is a unique instrument for the generation of intense beams of metal ions as well as gaseous ions, including mixed metal–gas beams with controllable metal:gas ion ratio. Here we describe our exploratory work on the application of vacuum arc ion source-generated ion beams for ion implantation into polymer textile materials for modification of their biological cell compatibility surface properties. We have investigated two specific aspects of cell compatibility: (i) enhancement of the antibacterial characteristics (we chose to use Staphylococcus aureus bacteria) of ion implanted polymer textile fabric, and (ii) the “inverse” concern of enhancement of neural cell growth rate (we chose Rat B-35 neuroblastoma cells) on ion implanted polymer textile. The results of both investigations were positive, with implantation-generated antibacterial efficiency factor up to about 90%, fully comparable to alternative conventional (non-implantation) approaches and with some potentially important advantages over the conventional approach; and with enhancement of neural cell growth rate of up to a factor of 3.5 when grown on suitably implanted polymer textile material

  7. Qualitative evaluation of titanium implant integration into bone by diffraction enhanced imaging.

    Wagner, A; Sachse, A; Keller, M; Aurich, M; Wetzel, W-D; Hortschansky, P; Schmuck, K; Lohmann, M; Reime, B; Metge, J; Arfelli, F; Menk, R; Rigon, L; Muehleman, C; Bravin, A; Coan, P; Mollenhauer, J

    2006-03-07

    Diffraction enhanced imaging (DEI) uses refraction of x-rays at edges, which allows pronounced visualization of material borders and rejects scattering which often obscures edges and blurs images. Here, the first evidence is presented that, using DEI, a destruction-free evaluation of the quality of integration of metal implants into bone is possible. Experiments were performed in rabbits and sheep with model implants to investigate the option for DEI as a tool in implant research. The results obtained from DEI were compared to conventional histology obtained from the specimens. DE images allow the identification of the quality of ingrowth of bone into the hydroxyapatite layer of the implant. Incomplete integration of the implant with a remaining gap of less than 0.3 mm caused the presence of a highly refractive edge at the implant/bone border. In contrast, implants with bone fully grown onto the surface did not display a refractive signal. Therefore, the refractive signal could be utilized to diagnose implant healing and/or loosening.

  8. Qualitative evaluation of titanium implant integration into bone by diffraction enhanced imaging

    Wagner, A [Department of Orthopaedics of the University of Jena at the Waldkrankenhaus ' Rudolf Elle' , Jena (Germany); Sachse, A [Department of Orthopaedics of the University of Jena at the Waldkrankenhaus ' Rudolf Elle' , Jena (Germany); Keller, M [Department of Orthopaedics of the University of Jena at the Waldkrankenhaus ' Rudolf Elle' , Jena (Germany); Aurich, M [Department of Orthopaedics of the University of Jena at the Waldkrankenhaus ' Rudolf Elle' , Jena (Germany); Wetzel, W-D [Department of Orthopaedics of the University of Jena at the Waldkrankenhaus ' Rudolf Elle' , Jena (Germany); Hortschansky, P [Hans-Knoell-Institut fuer Naturstoffforschung, Jena (Germany); Schmuck, K [DePuy Biotech GmbH, Jena (Germany); Lohmann, M [Hasylab at DESY, Hamburg (Germany); Reime, B [Hasylab at DESY, Hamburg (Germany); Metge, J [CELLS-ALBA, Universitat Autonoma de Barcelona (Spain); Arfelli, F [Department of Physics, University of Trieste, Trieste (Italy); Menk, R [ELETTRA, Trieste (Italy); Rigon, L [ELETTRA, Trieste (Italy); Muehleman, C [Department of Biochemistry, Rush Medical College, Chicago, IL (United States); Bravin, A [European Synchrotron Radiation Facility, BP220 38043, Grenoble (France); Coan, P [European Synchrotron Radiation Facility, BP220 38043, Grenoble (France); Mollenhauer, J [Department of Orthopaedics of the University of Jena at the Waldkrankenhaus ' Rudolf Elle' , Jena (Germany)

    2006-03-07

    Diffraction enhanced imaging (DEI) uses refraction of x-rays at edges, which allows pronounced visualization of material borders and rejects scattering which often obscures edges and blurs images. Here, the first evidence is presented that, using DEI, a destruction-free evaluation of the quality of integration of metal implants into bone is possible. Experiments were performed in rabbits and sheep with model implants to investigate the option for DEI as a tool in implant research. The results obtained from DEI were compared to conventional histology obtained from the specimens. DE images allow the identification of the quality of ingrowth of bone into the hydroxyapatite layer of the implant. Incomplete integration of the implant with a remaining gap of less than 0.3 mm caused the presence of a highly refractive edge at the implant/bone border. In contrast, implants with bone fully grown onto the surface did not display a refractive signal. Therefore, the refractive signal could be utilized to diagnose implant healing and/or loosening.

  9. Modification of anti-bacterial surface properties of textile polymers by vacuum arc ion source implantation

    Nikolaev, A.G., E-mail: nik@opee.hcei.tsc.ru [High Current Electronics Institute, Siberian Branch of the Russian Academy of Sciences, Tomsk 634055 (Russian Federation); Yushkov, G.Yu.; Oks, E.M. [High Current Electronics Institute, Siberian Branch of the Russian Academy of Sciences, Tomsk 634055 (Russian Federation); Oztarhan, A. [Izmir University, Izmir 35140 (Turkey); Akpek, A.; Hames-Kocabas, E.; Urkac, E.S. [Bioengineering Department, Ege University, Bornova 35100, Izmir (Turkey); Brown, I.G. [Lawrence Berkeley National Laboratory, Berkeley, CA 94708 (United States)

    2014-08-15

    Highlights: • Ion implantation. • Anti-bacterial properties. • Textile polymer. • Vacuum arc ion source. - Abstract: Ion implantation provides an important technology for the modification of material surface properties. The vacuum arc ion source is a unique instrument for the generation of intense beams of metal ions as well as gaseous ions, including mixed metal–gas beams with controllable metal:gas ion ratio. Here we describe our exploratory work on the application of vacuum arc ion source-generated ion beams for ion implantation into polymer textile materials for modification of their biological cell compatibility surface properties. We have investigated two specific aspects of cell compatibility: (i) enhancement of the antibacterial characteristics (we chose to use Staphylococcus aureus bacteria) of ion implanted polymer textile fabric, and (ii) the “inverse” concern of enhancement of neural cell growth rate (we chose Rat B-35 neuroblastoma cells) on ion implanted polymer textile. The results of both investigations were positive, with implantation-generated antibacterial efficiency factor up to about 90%, fully comparable to alternative conventional (non-implantation) approaches and with some potentially important advantages over the conventional approach; and with enhancement of neural cell growth rate of up to a factor of 3.5 when grown on suitably implanted polymer textile material.

  10. [Fully absorbable drug eluting coronary stent: where do we stand in 2014?].

    Kočka, Viktor; Toušek, Petr; Lisa, Libor; Buděšínský, Tomáš

    2014-04-01

    Coronary stent is routinely used in majority percutaneous coronary interventions for a long time. They have an important role, especially, in the first months after intervention. We can consider as a breakthrough point the development of stent which has ability to absorb in intervened artery after a few years. The review presents current techniques of fully absorbable coronary stents and also provides clinical trials and experiences available in 2014. The article continues with discussion between supporters and opponents of this new technique, but definitive conclusion can't be done yet. The authors conclude the review with their own opinion. There are many encouraging data in patients with good clinical outcome after implantation of absorbable stents in more than 10 years follow-up.

  11. Age at implantation and auditory memory in cochlear implanted children.

    Mikic, B; Miric, D; Nikolic-Mikic, M; Ostojic, S; Asanovic, M

    2014-05-01

    Early cochlear implantation, before the age of 3 years, provides the best outcome regarding listening, speech, cognition an memory due to maximal central nervous system plasticity. Intensive postoperative training improves not only auditory performance and language, but affects auditory memory as well. The aim of this study was to discover if the age at implantation affects auditory memory function in cochlear implanted children. A total of 50 cochlear implanted children aged 4 to 8 years were enrolled in this study: early implanted (1-3y) n = 27 and late implanted (4-6y) n = 23. Two types of memory tests were used: Immediate Verbal Memory Test and Forward and Backward Digit Span Test. Early implanted children performed better on both verbal and numeric tasks of auditory memory. The difference was statistically significant, especially on the complex tasks. Early cochlear implantation, before the age of 3 years, significantly improve auditory memory and contribute to better cognitive and education outcomes.

  12. Microstructure and mechanical properties of porous titanium structures fabricated by electron beam melting for cranial implants.

    Moiduddin, Khaja

    2018-02-01

    The traditional methods of metallic bone implants are often dense and suffer from adverse reactions, biomechanical mismatch and lack of adequate space for new bone tissue to grow into the implant. The objective of this study is to evaluate the customized porous cranial implant with mechanical properties closer to that of bone and to improve the aesthetic outcome in cranial surgery with precision fitting for a better quality of life. Two custom cranial implants (bulk and porous) are digitally designed based on the Digital Imaging and Communications in Medicine files and fabricated using additive manufacturing. Initially, the defective skull model and the implant were fabricated using fused deposition modeling for the purpose of dimensional validation. Subsequently, the implant was fabricated using titanium alloy (Ti6Al4V extra low interstitial) by electron beam melting technology. The electron beam melting-produced body diagonal node structure incorporated in cranial implant was evaluated based on its mechanical strength and structural characterization. The results show that the electron beam melting-produced porous cranial implants provide the necessary framework for the bone cells to grow into the pores and mimic the architecture and mechanical properties closer to the region of implantation. Scanning electron microscope and micro-computed tomography scanning confirm that the produced porous implants have a highly regular pattern of porous structure with a fully interconnected network channel without any internal defect and voids. The physical properties of the titanium porous structure, containing the compressive strength of 61.5 MPa and modulus of elasticity being 1.20 GPa, represent a promising means of reducing stiffness and stress-shielding effect on the surrounding bone. This study reveals that the use of porous structure in cranial reconstruction satisfies the need of lighter implants with an adequate mechanical strength and structural characteristics

  13. Cluster Implantation and Deposition Apparatus

    Hanif, Muhammad; Popok, Vladimir

    2015-01-01

    In the current report, a design and capabilities of a cluster implantation and deposition apparatus (CIDA) involving two different cluster sources are described. The clusters produced from gas precursors (Ar, N etc.) by PuCluS-2 can be used to study cluster ion implantation in order to develop...

  14. Porous metal for orthopedics implants

    Matassi, Fabrizio; Botti, Alessandra; Sirleo, Luigi; Carulli, Christian; Innocenti, Massimo

    2013-01-01

    Porous metal has been introduced to obtain biological fixation and improve longevity of orthopedic implants. The new generation of porous metal has intriguing characteristics that allows bone healing and high osteointegration of the metallic implants. This article gives an overview about biomaterials properties of the contemporary class of highly porous metals and about the clinical use in orthopaedic surgery.

  15. [The impact of dental implants

    Meijer, G.J.

    2013-01-01

    The importance of the introduction of dental implants can only be understood when the historical context is clarified. In the past, the main treatment carried out by dentists consisted of filling or, in unfortunate cases, removal of painful teeth. Only since the introduction of dental implants did

  16. Sequential provisional implant prosthodontics therapy.

    Zinner, Ira D; Markovits, Stanley; Jansen, Curtis E; Reid, Patrick E; Schnader, Yale E; Shapiro, Herbert J

    2012-01-01

    The fabrication and long-term use of first- and second-stage provisional implant prostheses is critical to create a favorable prognosis for function and esthetics of a fixed-implant supported prosthesis. The fixed metal and acrylic resin cemented first-stage prosthesis, as reviewed in Part I, is needed for prevention of adjacent and opposing tooth movement, pressure on the implant site as well as protection to avoid micromovement of the freshly placed implant body. The second-stage prosthesis, reviewed in Part II, should be used following implant uncovering and abutment installation. The patient wears this provisional prosthesis until maturation of the bone and healing of soft tissues. The second-stage provisional prosthesis is also a fail-safe mechanism for possible early implant failures and also can be used with late failures and/or for the necessity to repair the definitive prosthesis. In addition, the screw-retained provisional prosthesis is used if and when an implant requires removal or other implants are to be placed as in a sequential approach. The creation and use of both first- and second-stage provisional prostheses involve a restorative dentist, dental technician, surgeon, and patient to work as a team. If the dentist alone cannot do diagnosis and treatment planning, surgery, and laboratory techniques, he or she needs help by employing the expertise of a surgeon and a laboratory technician. This team approach is essential for optimum results.

  17. Piezosurgery in implant dentistry

    Stübinger S

    2015-11-01

    Full Text Available Stefan Stübinger,1 Andres Stricker,2 Britt-Isabelle Berg3,4 1Hightech Research Center of Cranio-maxillofacial Surgery, University of Basel, Allschwil, Switzerland; 2Private Practice, Konstanz, Germany; 3Department of Cranio-maxillofacial Surgery, University Hospital Basel, Basel, Switzerland; 4Division of Oral and Maxillofacial Radiology, Columbia University Medical Center, New York, NY, USA Abstract: Piezosurgery, or the use of piezoelectric devices, is being applied increasingly in oral and maxillofacial surgery. The main advantages of this technique are precise and selective cuttings, the avoidance of thermal damage, and the preservation of soft-tissue structures. Through the application of piezoelectric surgery, implant-site preparation, bone grafting, sinus-floor elevation, edentulous ridge splitting or the lateralization of the inferior alveolar nerve are very technically feasible. This clinical overview gives a short summary of the current literature and outlines the advantages and disadvantages of piezoelectric bone surgery in implant dentistry. Overall, piezoelectric surgery is superior to other methods that utilize mechanical instruments. Handling of delicate or compromised hard- and soft-tissue conditions can be performed with less risk for the patient. With respect to current and future innovative surgical concepts, piezoelectric surgery offers a wide range of new possibilities to perform customized and minimally invasive osteotomies. Keywords: implantology, piezoelectric device, piezosurgery, maxillary sinus elevation, bone grafting, osteotomy, edentulous ridge splitting

  18. Labyrinthectomy with cochlear implantation.

    Zwolan, T A; Shepard, N T; Niparko, J K

    1993-05-01

    Numerous reports indicate that the cochlea remains responsive to electrical stimulation following labyrinthectomy. We report a case of a 47-year-old woman with a severe to profound sensorineural hearing loss from birth, who developed episodic vertigo with symptoms suggestive of delayed onset endolymphatic hydrops. Following 8 months of failed medical and vestibular rehabilitation management, a right-sided labyrinthectomy combined with cochlear implantation was performed without complication. Postoperatively the patient was free of vertigo. Attempts to activate the patient's device between 4 to 12 weeks after surgery were unsuccessful as stimulation of the electrodes resulted in discomfort. However, all 20 electrodes elicited comfortable hearing sensations 16 weeks postsurgery. One year after the successful activation, the patient demonstrated improved sound awareness and speech recognition with the implant when compared with preoperative performance with a hearing aid. This case study suggests that electrical detection thresholds with prosthetic stimulation may be unstable in the recently labyrinthectomized ear but supports and extends prior observations of preserved cochlear responsiveness after labyrinthectomy.

  19. Implant prostheses for convertibility, stress control, esthetics, and hygiene.

    Garfield, R E

    1988-07-01

    A method of connecting "fixed partial denture" prostheses to osseointegrated implant fixtures has been described. The advantages of this system of restoration for partially and fully edentulous mouths are that it is more effective in addressing the problems of (1) stress-control on abutments, (2) a back-up system for abutment failures, (3) esthetics, and (4) control of bacterial plaques around abutments. To accomplish this procedure, the application of convertible periodontal prosthesis techniques with modifications to some existing implant systems is undertaken. The disadvantages of this method seem insignificant when one considers the complexities and risks involved with the present array of implant prosthesis alternatives. Some patients and dentists might consider the necessity of the prosthesis being detachable as one disadvantage. In reality, the prosthesis can be used as a fixed restoration until the patient has fully adapted to the new proprioception and appearance. A large percentage of patients feel uncomfortable with the word "removable" because it immediately creates a perception of unsightly metallic clasp display, palatal coverage, tongue interference, and negative body image. The use of the term "detachable" coupled with the doctor's offer to perform this task for the patient "whenever necessary" will usually relieve the patient's anxiety and allow the treatment to proceed. Once neuromuscular and esthetic adaptation have occurred and the patient has accepted the prosthesis, daily detaching and home-care hygiene by the patient will follow without incident. Esthetic improvement is obvious (Fig. 3).

  20. Immediate versus early non-occlusal loading of dental implants placed flapless in partially edentulous patients. One-year results from a randomised controlled trial.

    Merli, Mauro; Merli, Aldo; Bernardelli, Francesco; Lombardini, Francesco; Esposito, Marco

    2008-01-01

    To compare immediate versus early (6 weeks) non-occlusal loading of dental implants placed flapless in partially edentulous patients 1 year after loading. Sixty patients were randomised: 30 to the immediately loaded group and 30 to the early loaded group. In order to be immediately loaded, implants were inserted with a minimum torque of > or = 40Ncm. Implants were fully occlusally loaded after 6 months. Outcome measures were prosthesis and implant failures, and biological and biomechanical complications. Five implants in five patients randomised to the immediately loaded group did not reach the required primary implant stability. Three of these implants (two prostheses) were not immediately loaded. Two patients who were randomised to the early loaded group were immediately loaded erroneously. Implants in five patients of the early loaded group were conventionally loaded. No patient dropped out and there were no failures. Two complications occurred in the early and one in the immediately loaded group (no statistically significant difference), but were solved. The use of a flapless technique for placing dental implants in conjunction with non-occlusal immediate or early loading in selected patients can provide excellent clinical results. No differences were observed when comparing implants that were loaded immediately or early. Therefore, when a high primary implant stability is obtained, it might be preferable to load the implants immediately rather than waiting for a few weeks.

  1. Ion implantation and amorphous metals

    Hohmuth, K.; Rauschenbach, B.

    1981-01-01

    This review deals with ion implantation of metals in the high concentration range for preparing amorphous layers (>= 10 at%, implantation doses > 10 16 ions/cm 2 ). Different models are described concerning formation of amorphous phases of metals by ion implantation and experimental results are given. The study of amorphous phases has been carried out by the aid of Rutherford backscattering combined with the channeling technique and using transmission electron microscopy. The structure of amorphous metals prepared by ion implantation has been discussed. It was concluded that amorphous metal-metalloid compounds can be described by a dense-random-packing structure with a great portion of metal atoms. Ion implantation has been compared with other techniques for preparing amorphous metals and the adventages have been outlined

  2. Ion implantation: an annotated bibliography

    Ting, R.N.; Subramanyam, K.

    1975-10-01

    Ion implantation is a technique for introducing controlled amounts of dopants into target substrates, and has been successfully used for the manufacture of silicon semiconductor devices. Ion implantation is superior to other methods of doping such as thermal diffusion and epitaxy, in view of its advantages such as high degree of control, flexibility, and amenability to automation. This annotated bibliography of 416 references consists of journal articles, books, and conference papers in English and foreign languages published during 1973-74, on all aspects of ion implantation including range distribution and concentration profile, channeling, radiation damage and annealing, compound semiconductors, structural and electrical characterization, applications, equipment and ion sources. Earlier bibliographies on ion implantation, and national and international conferences in which papers on ion implantation were presented have also been listed separately

  3. Design of a statically balanced fully compliant grasper

    Lamers, A.J.; Gallego Sanchez, J.A.; Herder, Justus Laurens

    2015-01-01

    Monolithic and thus fully compliant surgical graspers are promising when they provide equal or better force feedback than conventional graspers. In this work for the first time a fully compliant grasper is designed to exhibit zero stiffness and zero operation force. The design problem is addressed

  4. Tribological properties of nitrogen implanted and boron implanted steels

    Kern, K.T.

    1996-01-01

    Samples of a steel with high chrome content was implanted separately with 75 keV nitrogen ions and with 75 keV boron ions. Implanted doses of each ion species were 2-, 4-, and 8 x 10 17 /cm 2 . Retained doses were measured using resonant non-Rutherford Backscattering Spectrometry. Tribological properties were determined using a pin-on-disk test with a 6-mm diameter ruby pin with a velocity of 0.94 m/min. Testing was done at 10% humidity with a load of 377 g. Wear rate and coefficient of friction were determined from these tests. While reduction in the wear rate for nitrogen implanted materials was observed, greater reduction (more than an order of magnitude) was observed for boron implanted materials. In addition, reduction in the coefficient of friction for high-dose boron implanted materials was observed. Nano-indentation revealed a hardened layer near the surface of the material. Results from grazing incidence x-ray diffraction suggest the formation of Fe 2 N and Fe 3 N in the nitrogen implanted materials and Fe 3 B in the boron implanted materials. Results from transmission electron microscopy will be presented

  5. Cochlear implantation in late-implanted adults with prelingual deafness.

    Most, Tova; Shrem, Hadas; Duvdevani, Ilana

    2010-01-01

    The purpose of this study was to examine the effect of cochlear implantation (CI) on prelingually deafened participants who were implanted as adults. The effect of the CI was examined with regard to the following variables: communication, family, social skills, education, and work satisfaction with one's life, loneliness, and self-esteem. Thirty-eight adults participated. Four self-report questionnaires were used at 2 points in time: before and after CI. The research findings show significant differences in the reports of most variables before and after implantation. The participants felt better with regard to communication, social skills, education, and work and satisfaction with one's life after implantation in comparison to their feelings before implantation. Furthermore, they felt less lonely after implantation. However, there were no significant differences before and after implantation regarding their feelings within the family and regarding their self-esteem. The results demonstrated the need to evaluate the benefits resulting from the CI not only with traditional clinical measures but with additional measures as well. Furthermore, they demonstrated the benefit of the CI on the positive psychosociological implications of prelingually deafened adults. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Cutaneous and systemic hypersensitivity reactions to metallic implants.

    Basko-Plluska, Juliana L; Thyssen, Jacob P; Schalock, Peter C

    2011-01-01

    Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous, and vasculitic eruptions may occur. Also, more complex immune reactions may develop around the implants, resulting in pain, inflammation, and loosening. Nickel, cobalt, and chromium are the three most common metals that elicit both cutaneous and extracutaneous allergic reactions from chronic internal exposure. However, other metal ions as well as bone cement components can cause such hypersensitivity reactions. To complicate things, patients may also develop delayed-type hypersensitivity reactions to metals (ie, in-stent restenosis, prosthesis loosening, inflammation, pain, or allergic contact dermatitis) following the insertion of intravascular stents, dental implants, cardiac pacemakers, or implanted gynecologic devices. Despite repeated attempts by researchers and clinicians to further understand this difficult area of medicine, the association between metal sensitivity and cutaneous allergic reactions remains to be fully understood. This review provides an update of the current knowledge in this field and should be valuable to health care providers who manage patients with conditions related to this field.

  7. Advances in Materials for Recent Low-Profile Implantable Bioelectronics

    Yanfei Chen

    2018-03-01

    Full Text Available The rapid development of micro/nanofabrication technologies to engineer a variety of materials has enabled new types of bioelectronics for health monitoring and disease diagnostics. In this review, we summarize widely used electronic materials in recent low-profile implantable systems, including traditional metals and semiconductors, soft polymers, biodegradable metals, and organic materials. Silicon-based compounds have represented the traditional materials in medical devices, due to the fully established fabrication processes. Examples include miniaturized sensors for monitoring intraocular pressure and blood pressure, which are designed in an ultra-thin diaphragm to react with the applied pressure. These sensors are integrated into rigid circuits and multiple modules; this brings challenges regarding the fundamental material’s property mismatch with the targeted human tissues, which are intrinsically soft. Therefore, many polymeric materials have been investigated for hybrid integration with well-characterized functional materials such as silicon membranes and metal interconnects, which enable soft implantable bioelectronics. The most recent trend in implantable systems uses transient materials that naturally dissolve in body fluid after a programmed lifetime. Such biodegradable metallic materials are advantageous in the design of electronics due to their proven electrical properties. Collectively, this review delivers the development history of materials in implantable devices, while introducing new bioelectronics based on bioresorbable materials with multiple functionalities.

  8. Advances in Materials for Recent Low-Profile Implantable Bioelectronics

    Kim, Yun-Soung; Tillman, Bryan W.; Chun, Youngjae

    2018-01-01

    The rapid development of micro/nanofabrication technologies to engineer a variety of materials has enabled new types of bioelectronics for health monitoring and disease diagnostics. In this review, we summarize widely used electronic materials in recent low-profile implantable systems, including traditional metals and semiconductors, soft polymers, biodegradable metals, and organic materials. Silicon-based compounds have represented the traditional materials in medical devices, due to the fully established fabrication processes. Examples include miniaturized sensors for monitoring intraocular pressure and blood pressure, which are designed in an ultra-thin diaphragm to react with the applied pressure. These sensors are integrated into rigid circuits and multiple modules; this brings challenges regarding the fundamental material’s property mismatch with the targeted human tissues, which are intrinsically soft. Therefore, many polymeric materials have been investigated for hybrid integration with well-characterized functional materials such as silicon membranes and metal interconnects, which enable soft implantable bioelectronics. The most recent trend in implantable systems uses transient materials that naturally dissolve in body fluid after a programmed lifetime. Such biodegradable metallic materials are advantageous in the design of electronics due to their proven electrical properties. Collectively, this review delivers the development history of materials in implantable devices, while introducing new bioelectronics based on bioresorbable materials with multiple functionalities. PMID:29596359

  9. A Retrospective Analysis of Ruptured Breast Implants

    Woo Yeol Baek

    2014-11-01

    Full Text Available BackgroundRupture is an important complication of breast implants. Before cohesive gel silicone implants, rupture rates of both saline and silicone breast implants were over 10%. Through an analysis of ruptured implants, we can determine the various factors related to ruptured implants.MethodsWe performed a retrospective review of 72 implants that were removed for implant rupture between 2005 and 2014 at a single institution. The following data were collected: type of implants (saline or silicone, duration of implantation, type of implant shell, degree of capsular contracture, associated symptoms, cause of rupture, diagnostic tools, and management.ResultsForty-five Saline implants and 27 silicone implants were used. Rupture was diagnosed at a mean of 5.6 and 12 years after insertion of saline and silicone implants, respectively. There was no association between shell type and risk of rupture. Spontaneous was the most common reason for the rupture. Rupture management was implant change (39 case, microfat graft (2 case, removal only (14 case, and follow-up loss (17 case.ConclusionsSaline implants have a shorter average duration of rupture, but diagnosis is easier and safer, leading to fewer complications. Previous-generation silicone implants required frequent follow-up observation, and it is recommended that they be changed to a cohesive gel implant before hidden rupture occurs.

  10. [Maintenance care for dental implant].

    Kamoi, K

    1989-10-01

    Dental implant has tried at the early stage in 19th century recovering an oral function and esthetics. Technological revolutions in biochemical and new materials have developed on the remarkable change in the dental implants, nowadays we call the three generation therapy for dental implantology. There are many kinds of methods and techniques in dental implants, however a lot of troublesome complication on the process of surgical phase, construction of prothodontics and prognosis of maintenance care. In the proceedings of this symposium, I would like to propose you how to manage the maintenance care for various kind of dental implants through the methodology and case presentations. Tendenay and future for dental implants The current outlook of dental implant has increasing supply and demand not only dentists but also patients. According to Japanese Welfare Ministry's report in 1987, average missing teeth over sixty years old generations are approximately 42% in accordance with NIDR (U.S.A.) research. They are missed on ten over teeth in full 28th teeth dentitions owing to dental caries and periodontal diseases. Generally speaking, latent implant patients are occupied on the same possibility of needs for dental implants both Japan and U.S.A. Management of maintenance care The patients hardly recognized the importance of plaque control for the maintenance care in the intraoral condition after implantation. Dentists and dental staffs must be instruct patients for importance of plaque removal and control, because they already had forgotten the habit of teeth cleaning, especially in the edenturous conditions. 1) Concept of establishment in oral hygiene. Motivation and instruction for patients include very important factors in dental implants as well as in periodontal diseases. Patients who could not achieve on good oral hygiene levels obtained no good results in the long term observations. To establish good oral hygiene are how to control supra plaque surrounding tissues

  11. Deep ion implantation for bipolar silicon devices; investigations into the use of the third dimension

    Mouthaan, A.J.

    1986-01-01

    This thesis covers various aspects of the use of deep ion implantations in digital bipolar circuits. It starts with the implications of the use of deep ion implantations for numerical process, device and circuit simulation. It shows the use of 1MeV boron and phosphorus implantations in the realization of a fully vertical IIL, here named Buried Injector Logic, which can also be used as static and dynamic memory device in several different configurations. The author presents a combined MOS-bipolar device, called the Charge Injection Device as a dynamic memory cell. Finally, deep ion implantations are used to realize a stack of photovoltaic cells that produces a multiple of the open circuit voltage of one photodiode. (Auth.)

  12. Wireless power transfer and data communication for neural implants case study : epilepsy monitoring

    Yilmaz, Gürkan

    2017-01-01

    This book presents new circuits and systems for implantable biomedical applications targeting neural recording. The authors describe a system design adapted to conform to the requirements of an epilepsy monitoring system. Throughout the book, these requirements are reflected in terms of implant size, power consumption, and data rate. In addition to theoretical background which explains the relevant technical challenges, the authors provide practical, step-by-step solutions to these problems. Readers will gain understanding of the numerical values in such a system, enabling projections for feasibility of new projects. Provides complete, system-level perspective for implantable batteryless biomedical system; Extends design example to implementation and long term in-vitro validation; Discusses system design concerns regarding wireless power transmission and wireless data communication, particularly for systems in which both are performed on the same channel/frequency; Presents fully-integrated, implantable syste...

  13. Deuterium migration and trapping in uranium and uranium dioxide during D+ implantation

    Lewis, M.B.

    1980-01-01

    Uranium and UO 2 have been implanted with deuterium ions in the energy range 30-85 keV. Subsequently, the near surface regions (100-90000 Angstroem) of these samples were quantitatively profiled for deuterium oxygen using the method of ion beam microanalysis. Mean ranges and widths of the implanted ions were measured and compared with theoretical predictions. Fully oxidized samples were compared with those having only thin oxide films on their surfaces. While the deuterium appeared to migrate during its implantation in uranium, little or no migration appeared either during or after implantation in UO 2 . Further measurements suggest that thin surface oxide films strongly trap the deuterium migrating beneath the surface. It is suggested that the electronic energy loss of the ion beam lowers the effective activation energy for the formation of OD bonds near the target surface. (orig.)

  14. Ion implantation apparatus

    Forneris, J.L.; Hicks, W.W.; Keller, J.H.; McKenna, C.M.; Siermarco, J.A.; Mueller, W.F.

    1981-01-01

    The invention relates to ion bombardment or implantation apparatus. It comprises an apparatus for bombarding a target with a beam of ions, including an arrangement for measuring the ion beam current and controlling the surface potential of the target. This comprises a Faraday cage formed, at least in part, by the target and by walls adjacent to, and electrically insulated from, the target and surrounding the beam. There is at least one electron source for supplying electrons to the interior of the Faraday cage and means within the cage for blocking direct rectilinear radiation from the source to the target. The target current is measured and combined with the wall currents to provide a measurement of the ion beam current. The quantity of electrons supplied to the interior of the cage can be varied to control the target current and thereby the target surface potential. (U.K.)

  15. Implantable biochemical fuel cell

    Richter, G; Rao, J R

    1978-01-05

    Implantable biochemical fuel cells for the operation of heart pacemakers or artificial hearts convert oxidisable body substances such as glucose on the anode side and reduce the oxygen contained in body fluids at the cathode. The anode and cathode are separated by membranes which are impermeable to albumen and blood corpuscles in body fluids. A chemical shortcircuit cannot occur in practice if, according to the invention, one or more selective oxygen electrodes with carbon as catalyst are arranged so that the mixture which diffuses into the cell from body fluids during operation reaches the fuel cell electrode through the porous oxygen electrode. The membranes used must be permeable to water. Cellulose, polymerised polyvinyl alcohol or an ion exchanger with a buffering capacity between pH5 and 8 act as permeable materials.

  16. Prosthesis-guided implant restoration of an auricular defect using computed tomography and 3-dimensional photographic imaging technologies: a clinical report.

    Wang, Shuming; Leng, Xu; Zheng, Yaqi; Zhang, Dapeng; Wu, Guofeng

    2015-02-01

    The concept of prosthesis-guided implantation has been widely accepted for intraoral implant placement, although clinicians do not fully appreciate its use for facial defect restoration. In this clinical report, multiple digital technologies were used to restore a facial defect with prosthesis-guided implantation. A simulation surgery was performed to remove the residual auricular tissue and to ensure the correct position of the mirrored contralateral ear model. The combined application of computed tomography and 3-dimensional photography preserved the position of the mirrored model and facilitated the definitive implant-retained auricular prosthesis. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  17. Implant materials modified by colloids

    Zboromirska-Wnukiewicz Beata

    2016-03-01

    Full Text Available Recent advances in general medicine led to the development of biomaterials. Implant material should be characterized by a high biocompatibility to the tissue and appropriate functionality, i.e. to have high mechanical and electrical strength and be stable in an electrolyte environment – these are the most important properties of bioceramic materials. Considerations of biomaterials design embrace also electrical properties occurring on the implant-body fluid interface and consequently the electrokinetic potential, which can be altered by modifying the surface of the implant. In this work, the surface of the implants was modified to decrease the risk of infection by using metal colloids. Nanocolloids were obtained using different chemical and electrical methods. It was found that the colloids obtained by physical and electrical methods are more stable than colloids obtained by chemical route. In this work the surface of modified corundum implants was investigated. The implant modified by nanosilver, obtained by electrical method was selected. The in vivo research on animals was carried out. Clinical observations showed that the implants with modified surface could be applied to wounds caused by atherosclerotic skeleton, for curing the chronic and bacterial inflammations as well as for skeletal reconstruction surgery.

  18. Basic research on maxillofacial implants

    Matsui, Yoshiro [Showa Univ., Tokyo (Japan). School of Dentistry

    2001-11-01

    Osseointegrated implants have begun to be used not only in general practice in dentistry but also in various clinical situations in the maxillofacial region. The process has yielded three problems: the spread of application, new materials and diagnostic methods, and management for difficult situations. This paper presents basic data and clinical guidelines for new applications, it investigates the characteristics of the materials and the usefulness of a new diagnostic method, and it studies effective techniques for difficult cases. The results obtained are as follows: Investigations into the spreading application. The lateral and superior orbital rim have sufficient bone thickness and width for the implant body to be placed. Osseointegrated implants, especially by the fixed bridge technique, are not recommended in the craniofacial bone and jaws of young children. Implant placement into bone after/before irradiation must be performed in consideration of impaired osteogenesis, the decrease of trabecular bone, and the time interval between implantation and irradiation. Investigations into materials and diagnostic methods. Hydroxyapatite-coated and titanium implants should be selected according to the characteristics of the materials. A dental simulating soft may also be applicable in the craniofacial region. Investigations into the management of difficult cases. Hyperbaric oxygen therapy (HBO), bone morphogenetic protein (BMP), and tissue engineering should be useful for improving the quality and increasing the quantity of bone where implants are placed. Soft tissue around implants placed in the reconstructed area should be replaced with mucosal tissue. The data obtained here should be useful for increasing the efficiency of osseointegrated implants, but further basic research is required in the future. (author)

  19. Basic research on maxillofacial implants

    Matsui, Yoshiro

    2001-01-01

    Osseointegrated implants have begun to be used not only in general practice in dentistry but also in various clinical situations in the maxillofacial region. The process has yielded three problems: the spread of application, new materials and diagnostic methods, and management for difficult situations. This paper presents basic data and clinical guidelines for new applications, it investigates the characteristics of the materials and the usefulness of a new diagnostic method, and it studies effective techniques for difficult cases. The results obtained are as follows: Investigations into the spreading application. The lateral and superior orbital rim have sufficient bone thickness and width for the implant body to be placed. Osseointegrated implants, especially by the fixed bridge technique, are not recommended in the craniofacial bone and jaws of young children. Implant placement into bone after/before irradiation must be performed in consideration of impaired osteogenesis, the decrease of trabecular bone, and the time interval between implantation and irradiation. Investigations into materials and diagnostic methods. Hydroxyapatite-coated and titanium implants should be selected according to the characteristics of the materials. A dental simulating soft may also be applicable in the craniofacial region. Investigations into the management of difficult cases. Hyperbaric oxygen therapy (HBO), bone morphogenetic protein (BMP), and tissue engineering should be useful for improving the quality and increasing the quantity of bone where implants are placed. Soft tissue around implants placed in the reconstructed area should be replaced with mucosal tissue. The data obtained here should be useful for increasing the efficiency of osseointegrated implants, but further basic research is required in the future. (author)

  20. Surface modifications of dental implants.

    Stanford, C M

    2008-06-01

    Dental implant surface technologies have been evolving rapidly to enhance a more rapid bone formation on their surface and hold a potential to increase the predictability of expedited implant therapy. While implant outcomes have become highly predictable, there are sites and conditions that result in elevated implant loss. This paper reviews the impact of macro-retentive features which includes approaches to surface oxide modification, thread design, press-fit and sintered-bead technologies to increase predictability of outcomes. Implant designs that lead to controlled lateral compression of the bone can improve primary stability as long as the stress does not exceed the localized yield strength of the cortical bone. Some implant designs have reduced crestal bone loss by use of multiple cutting threads that are closely spaced, smoothed on the tip but designed to create a hoop-stress stability of the implant as it is completely seated in the osteotomy. Following the placement of the implant, there is a predictable sequence of bone turnover and replacement at the interface that allows the newly formed bone to adapt to microscopic roughness on the implant surface, and on some surfaces, a nanotopography (<10(-9) m scale) that has been shown to preferably influence the formation of bone. Newly emerging studies show that bone cells are exquisitely sensitive to these topographical features and will upregulate the expression of bone related genes for new bone formation when grown on these surfaces. We live in an exciting time of rapid changes in the modalities we can offer patients for tooth replacement therapy. Given this, it is our responsibility to be critical when claims are made, incorporate into our practice what is proven and worthwhile, and to continue to support and provide the best patient care possible.

  1. COCHLEAR IMPLANTATION PREVALENCE IN ELDERLY

    A. V. Starokha

    2014-01-01

    Full Text Available Current paper describes an experience of cochlear implantation in elderly. Cochlear implantation has become a widely accepted intervention in the treatment of individuals with severe-to-profound sensorineural hearing loss. Cochlear implants are now accepted as a standard of care to optimize hearing and subsequent speech development in children and adults with deafness. But cochlear implantation affects not only hearing abilities, speech perception and speech production; it also has an outstanding impact on the social life, activities and self-esteem of each patient. The aim of this study was to evaluate the cochlear implantation efficacy in elderly with severe to profound sensorineural hearing loss. There were 5 patients under our observation. Surgery was performed according to traditional posterior tympanotomy and cochleostomy for cochlear implant electrode insertion for all observed patients. The study was conducted in two stages: before speech processor’s activation and 3 months later. Pure tone free field audiometry was performed to each patient to assess the efficiency of cochlear implantation in dynamics. The aim of the study was also to evaluate quality of life in elderly with severe to profound sensorineural hearing loss after unilateral cochlear implantation. Each patient underwent questioning with 36 Item Short Form Health Survey (SF-36. SF-36 is a set of generic, coherent, and easily administered quality-of-life measures. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The eight sections are: physical functioning; physical role functioning; emotional role functioning; vitality; emotional well-being; social role functioning; bodily pain; general health perceptions. Our results demonstrate that cochlear implantation in elderly consistently improved quality of life

  2. Scalloped Implant-Abutment Connection Compared to Conventional Flat Implant-Abutment Connection

    Starch-Jensen, Thomas; Christensen, Ann-Eva; Lorenzen, Henning

    2017-01-01

    OBJECTIVES: The objective was to test the hypothesis of no difference in implant treatment outcome after installation of implants with a scalloped implant-abutment connection compared to a flat implant-abutment connection. MATERIAL AND METHODS: A MEDLINE (PubMed), Embase and Cochrane library search...... of suprastructures has never been compared within the same study. High implant survival rate was reported in all the included studies. Significantly more peri-implant marginal bone loss, higher probing depth score, bleeding score and gingival score was observed around implants with a scalloped implant-abutment...... loss around implants with a scalloped implant-abutment connection. CONCLUSIONS: A scalloped implant-abutment connection seems to be associated with higher peri-implant marginal bone loss compared to a flat implant-abutment connection. Therefore, the hypothesis of the present systematic review must...

  3. Implantable cardioverter defibrillator implantation in children in The Netherlands

    Ten Harkel, ADJ; Blom, NA; Reimer, AG; Tukkie, R; Sreeram, N; Bink-Boelkens, MTE

    To evaluate the indications, underlying cardiac disorders, efficacy and complications involved with implantable cardioverter-defibrillators (ICDs) in paediatric patients in The Netherlands, the records of all patients aged 18 years or younger who underwent ICD placement were reviewed

  4. Implantable cardioverter defibrillator implantation in children in The Netherlands

    ten Harkel, A. Derk Jan; Blom, Nico A.; Reimer, Annette G.; Tukkie, Raymond; Sreeram, Narayanswami; Bink-Boelkens, Margreet T. E.

    2005-01-01

    To evaluate the indications, underlying cardiac disorders, efficacy and complications involved with implantable cardioverter-defibrillators (ICDs) in paediatric patients in The Netherlands, the records of all patients aged 18 years or younger who underwent ICD placement were reviewed

  5. Nitrogen implantation in steel with an impulsive ion implanter

    Feugeas, J.N.; Gonzalez, C.O.; Hermida, J.; Nieto, M.; Peyronel, M.F.; Sanchez, G.

    1990-01-01

    This work describes the results of steel implantation with nitrogen, with a pulsed accelerator which provides a continuous ion energy spectrum giving a uniform profile of nitrogen without changing its operative conditions. (Author)

  6. Ion implantation in semiconductor bodies

    Badawi, M.H.

    1984-01-01

    Ions are selectively implanted into layers of a semiconductor substrate of, for example, semi-insulating gallium arsenide via a photoresist implantation mask and a metallic layer of, for example, titanium disposed between the substrate surface and the photoresist mask. After implantation the mask and metallic layer are removed and the substrate heat treated for annealing purposes. The metallic layer acts as a buffer layer and prevents possible contamination of the substrate surface, by photoresist residues, at the annealing stage. Such contamination would adversely affect the electrical properties of the substrate surface, particularly gallium arsenide substrates. (author)

  7. Hardness of ion implanted ceramics

    Oliver, W.C.; McHargue, C.J.; Farlow, G.C.; White, C.W.

    1985-01-01

    It has been established that the wear behavior of ceramic materials can be modified through ion implantation. Studies have been done to characterize the effect of implantation on the structure and composition of ceramic surfaces. To understand how these changes affect the wear properties of the ceramic, other mechanical properties must be measured. To accomplish this, a commercially available ultra low load hardness tester has been used to characterize Al 2 O 3 with different implanted species and doses. The hardness of the base material is compared with the highly damaged crystalline state as well as the amorphous material

  8. Antimicrobial mouthrinse use as an adjunct method in peri-implant biofilm control

    Vinicius PEDRAZZI

    2014-01-01

    Full Text Available Great possibilities for oral rehabilitation emerged as a result of scientific consolidation, as well as a large number of dental implant applications. Along with implants appeared diseases such as mucositis and peri-implantitis, requiring management through several strategies applied at different stages. Biofilm accumulation is associated with clinical signs manifest by both tooth and implant inflammation. With this in mind, regular and complete biofilm elimination becomes essential for disease prevention and host protection. Chemical control of biofilms, as an adjuvant to mechanical oral hygiene, is fully justified by its simplicity and efficacy proven by studies based on clinical evidence. The purpose of this review was to present a consensus regarding the importance of antimicrobial mouthrinse use as an auxiliary method in chemical peri-implant biofilm control. The active ingredients of the several available mouthrinses include bis-biguanide, essential oils, phenols, quaternary ammonium compounds, oxygenating compounds, chlorine derivatives, plant extracts, fluorides, antibiotics and antimicrobial agent combinations. It was concluded that there is strong clinical evidence that at least two mouthrinses have scientifically proven efficacy against different oral biofilms, i.e., chlorhexidine digluconate and essential oils; however, 0.12% chlorhexidine digluconate presents a number of unwanted side effects and should be prescribed with caution. Chemical agents seem beneficial in controlling peri-implant inflammation, although they require further investigation. We recommend a scientifically proven antiseptic, with significant short and long term efficacy and with no unwanted side effects, for the prevention and/or treatment of peri-implant disease.

  9. Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted 163Ho ions

    Gastaldo, L.; Ranitzsch, P. C.-O.; von Seggern, F.; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

    2013-05-01

    For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of 163Ho using MMCs having the radioactive 163Ho ions implanted in the absorber. The isotope 163Ho decays through electron capture to 163Dy and features the smallest known QEC value. This peculiarity makes 163Ho a very interesting candidate to investigate the value of the electron neutrino mass by the analysis of the energy spectrum. The implantation of 163Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. Moreover the performance of the detector prototype having the 163Ho ions implanted in the absorber is already close to the requirements needed for an experiment with sub-eV sensitivity to the electron neutrino mass. Based on these results, an optimized detector design for future 163Ho experiments is presented.

  10. Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted 163Ho ions

    Gastaldo, L.; Ranitzsch, P.C.-O.; Seggern, F. von; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

    2013-01-01

    For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of 163 Ho using MMCs having the radioactive 163 Ho ions implanted in the absorber. The isotope 163 Ho decays through electron capture to 163 Dy and features the smallest known Q EC value. This peculiarity makes 163 Ho a very interesting candidate to investigate the value of the electron neutrino mass by the analysis of the energy spectrum. The implantation of 163 Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. Moreover the performance of the detector prototype having the 163 Ho ions implanted in the absorber is already close to the requirements needed for an experiment with sub-eV sensitivity to the electron neutrino mass. Based on these results, an optimized detector design for future 163 Ho experiments is presented

  11. An introduction to single implant abutments.

    Warreth, Abdulhadi

    2013-01-01

    This article is an introduction to single implant abutments and aims to provide basic information about abutments which are essential for all dental personnel who are involved in dental implantology. Clinical Relevance: This article provides a basic knowledge of implants and implant abutments which are of paramount importance, as replacement of missing teeth with oral implants has become a well-established clinical procedure.

  12. Cochlear implantation in a bilateral Mondini dysplasia.

    Turrini, M; Orzan, E; Gabana, M; Genovese, E; Arslan, E; Fisch, U

    1997-01-01

    We report the speech perception progress and programming procedures of a case of congenital profound deafness and bilateral Mondini dysplasia implanted with a Nucleus 20 + 2 cochlear implant at the age of six. Unclear relations between electrodes array and cochlear partition made implant programming difficult and non-standard procedures were set. Cochlear implantation may give excellent rehabilitative results also in cochleae with malformation.

  13. Implant retention systems for implant-retained overdentures.

    Laverty, D P; Green, D; Marrison, D; Addy, L; Thomas, M B M

    2017-03-10

    Implant retained overdentures are being increasingly utilised in both general and specialist practice to rehabilitate patients with missing teeth, particularly those that are edentate. This article aims to inform the reader of a variety of retention systems that are available to retain an implant overdenture and to understand how these systems work, their advantages and disadvantages and to outline some of the clinical and treatment planning considerations involved in selecting the most appropriate retention system for patients.

  14. Implant Materials Generate Different Peri-implant Inflammatory Factors

    Olivares-Navarrete, Rene; Hyzy, Sharon L.; Slosar, Paul J.; Schneider, Jennifer M.; Schwartz, Zvi; Boyan, Barbara D.

    2015-01-01

    Study Design. An in vitro study examining factors produced by human mesenchymal stem cells on spine implant materials. Objective. The aim of this study was to examine whether the inflammatory microenvironment generated by cells on titanium-aluminum-vanadium (Ti-alloy, TiAlV) surfaces is affected by surface microtexture and whether it differs from that generated on poly-ether-ether-ketone (PEEK). Summary of Background Data. Histologically, implants fabricated from PEEK have a fibrous connectiv...

  15. Analysis of metallic traces from the biodegradation of endomedullary AZ31 alloy temporary implants in rat organs after long implantation times.

    Bodelón, O G; Iglesias, C; Garrido, J; Clemente, C; Garcia-Alonso, M C; Escudero, M L

    2015-08-04

    AZ31 alloy has been tested as a biodegradable material in the form of endomedullary implants in female Wistar rat femurs. In order to evaluate the accumulation of potentially toxic elements from the biodegradation of the implant, magnesium (Mg), aluminium (Al), zinc (Zn), manganese (Mn) and fluorine (F) levels have been measured in different organs such as kidneys, liver, lungs, spleen and brain. Several factors that may influence accumulation have been taken into account: how long the implant has been in place, whether or not the bone is fractured, and the presence of an MgF2 protective coating on the implant. The main conclusions and the clinical relevance of the study have been that AZ31 endomedullary implants have a degradation rate of about 60% after 13 months, which is fully compatible with fracture consolidation. Neither bone fracture nor an MgF2 coating seems to influence the accumulation of trace elements in the studied organs. Aluminium is the only alloying element in this study that requires special attention. The increase in Al recovered from the sampled organs represents 3.95% of the amount contained in the AZ31 implant. Al accumulates in a statistically significant way in all the organs except the brain. All of this suggests that in long-term tests AZ31 may be a suitable material for osteosynthesis.

  16. Structure of ion-implanted ceramics

    Naramoto, Hiroshi

    1983-01-01

    The variation of structure of LiF, MgO, Al 2 O 3 and TiO 2 accompanying annealing after ion implantation is explained. The analysis of structure is usually made by the perturbed gamma ray angular correlation, the internal electron Moessbauer method, or the ion scattering method. The results of analyses are discussed for alkali ion implantation, Fe-ion implantation, In-ion implantation, Au-ion implantation, Pt-ion implantation, Pb-ion implantation and transition metal ion implantation. The coupling of the implanted elements with lattice defects and matrix elements, and the compatibility between deposited elements and matrix crystal lattice were studied. The variation of physical properties due to ion implantation such as phase transition, volume change, the control of single crystal region, and the variation of hardness near surface were investigated, and the examples are presented. (Kato, T.)

  17. Fully deuterated microorganisms: Tools in magnetic resonance and neutron scattering

    Crespi, H.L.

    1988-01-01

    Current work at Argonne emphasizes the use of fully deuterated algae and cyanobacteria as tools in the study of photosynthesis and as a source of complex substrates for the culture of engineered overproducing bacteria. 17 refs., 1 fig., 1 tab

  18. Measles: Make Sure Your Child Is Fully Immunized

    ... this? Submit What's this? Submit Button Past Emails Measles: Make Sure Your Child is Fully Immunized Language: ... also become infected if they are not protected. Measles in the U.S. From January 2 to March ...

  19. Fully differential cross sections for heavy particle impact ionization

    McGovern, M; Walters, H R J [Department of Applied Mathematics and Theoretical Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Assafrao, D; Mohallem, J R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, P.O Box 702, 30123-970 Belo Horizonte, MG (Brazil); Whelan, Colm T, E-mail: mmcgovern06@qub.ac.u [Department of Physics, Old Dominion University, Norfolk, VA 23529-0116 (United States)

    2009-11-15

    We describe a procedure for extracting fully differential ionization cross sections from an impact parameter coupled pseudostate treatment of the collision. Some examples from antiproton impact ionization of atomic Hydrogen are given.

  20. Multi-Branch Fully Convolutional Network for Face Detection

    Bai, Yancheng; Ghanem, Bernard

    2017-01-01

    Face detection is a fundamental problem in computer vision. It is still a challenging task in unconstrained conditions due to significant variations in scale, pose, expressions, and occlusion. In this paper, we propose a multi-branch fully

  1. Solving Fully Fuzzy Linear System of Equations in General Form

    A. Yousefzadeh

    2012-06-01

    Full Text Available In this work, we propose an approach for computing the positive solution of a fully fuzzy linear system where the coefficient matrix is a fuzzy $nimes n$ matrix. To do this, we use arithmetic operations on fuzzy numbers that introduced by Kaffman in and convert the fully fuzzy linear system into two $nimes n$ and $2nimes 2n$ crisp linear systems. If the solutions of these linear systems don't satisfy in positive fuzzy solution condition, we introduce the constrained least squares problem to obtain optimal fuzzy vector solution by applying the ranking function in given fully fuzzy linear system. Using our proposed method, the fully fuzzy linear system of equations always has a solution. Finally, we illustrate the efficiency of proposed method by solving some numerical examples.

  2. Fully-distributed randomized cooperation in wireless sensor networks

    Bader, Ahmed

    2015-01-07

    When marrying randomized distributed space-time coding (RDSTC) to geographical routing, new performance horizons can be created. In order to reach those horizons however, routing protocols must evolve to operate in a fully distributed fashion. In this letter, we expose a technique to construct a fully distributed geographical routing scheme in conjunction with RDSTC. We then demonstrate the performance gains of this novel scheme by comparing it to one of the prominent classical schemes.

  3. Combining Semi-Endogenous and Fully Endogenous Growth: a Generalization.

    Cozzi, Guido

    2017-01-01

    This paper shows that combining the semi-endogenous and the fully endogenous growth mechanisms with a general CES aggregator, either growth process can prevail in the balanced growth path depending on their degree of complementarity/substitutability. Policy-induced long-run economic switches to the fully endogenous steady state as the R&D employment ratio surpasses a positive threshold are possible if the two growth engines are gross substitutes.

  4. A Concept Analysis of Fully Informed: Breastfeeding Promotion

    2005-12-21

    updated breastfeeding policy statement, the American Academy of Pediatrics 3 ( AAP , 2005) identified the compelling advantages of breastfeeding and urged...healthcare 4 professionals to implement principles to promote breastfeeding . The AAP cited obstacles 5 to the initiation and continuation of...Analysis of Fully Informed 2 14 A Concept Analysis of Fully Informed: Breastfeeding Promotion 15 In February 2005, the American Academy of Pediatrics ( AAP

  5. Fully-distributed randomized cooperation in wireless sensor networks

    Bader, Ahmed; Abed-Meraim, Karim; Alouini, Mohamed-Slim

    2015-01-01

    When marrying randomized distributed space-time coding (RDSTC) to geographical routing, new performance horizons can be created. In order to reach those horizons however, routing protocols must evolve to operate in a fully distributed fashion. In this letter, we expose a technique to construct a fully distributed geographical routing scheme in conjunction with RDSTC. We then demonstrate the performance gains of this novel scheme by comparing it to one of the prominent classical schemes.

  6. Surface microhardening by ion implantation

    Singh, Amarjit

    1986-01-01

    The paper discusses the process and the underlying mechanism of surface microhardening by implanting suitable energetic ions in materials like 4145 steel, 304 stainless steel, aluminium and its 2024-T351 alloy. It has been observed that boron and nitrogen implantation in materials like 4145 steel and 304 stainless steel can produce a significant increase in surface hardness. Moreover the increase can be further enhanced with suitable overlay coatings such as aluminium (Al), Titanium (Ti) and carbon (C). The surface hardening due to implantation is attributed to precipitation hardening or the formation of stable/metastable phase or both. The effect of lithium implantation in aluminium and its alloy on microhardness with increasing ion dose and ion beam energy is also discussed. (author)

  7. Implanted-tritium permeation experiments

    Longhurst, G.R.; Holland, D.F.; Casper, L.A.; Hsu, P.Y.; Miller, L.G.; Schmunk, R.E.; Watts, K.D.; Wilson, C.J.; Kershner, C.J.; Rogers, M.L.

    1982-04-01

    In fusion reactors, charge exchange neutral atoms of tritium coming from the plasma will be implanted into the first wall and other interior structures. EG and G Idaho is conducting two experiments to determine the magnitude of permeation into the coolant streams and the retention of tritium in those structures. One experiment uses an ion gun to implant deuterium. The ion gun will permit measurements to be made for a variety of implantation energies and fluxes. The second experiment utilizes a fission reactor to generate a tritium implantation flux by the 3 He(n,p) 3 H reaction. This experiment will simulate the fusion reactor radiation environment. We also plan to verify a supporting analytical code development program, in progress, by these experiments

  8. Dental-Implantate und ihre Werkstoffe

    Newesely, Heinrich

    1983-07-01

    Some new trends in materials for dental implants, which also effect in the operative techniques and implant design, are described. Advantages and shortcomings of the different material types are exemplified and correlated with their bioinert resp. bioactive functions. The practical interest in metallic implants focussed in titanium resp. oxide ceramics in the ceramic field, whereas the special goal of implant research follows from the improvement of the bioactive principle with loaded calcium phosphate implants.

  9. Biodegradable Implants in Orthopaedics and Traumatology

    YETKIN, Haluk

    2014-01-01

    Biodegradable implants are an alternative to metallic implants and have the advantage of not being necessary to remove once the fracture has healed. Twenty-two patients with fractures were treated with biodegradable implants. There were osteolysis in eleven patients; however, no serious complication was encountered. Although biodegradable implants are expensive, a second surgical procedure to remove the implants is not necessary, relieving the patient of the related costs and risks.

  10. Basics of clinical diagnosis in implant dentistry

    Manu Rathee

    2015-01-01

    Full Text Available Implant-based prosthetic rehabilitation requires an understanding of associated anatomical structures. The ultimate predictability of an implant site is determined by the existing anatomy as related to dentition and the associated hard and soft tissues. Meticulous clinical assessment helps in determining the suitability of the potential site for implant placement. The purpose of this article is to present the clinical assessment for dental implants' placement to modulate peri-implant tissue characteristics in individual clinical need.

  11. Incidence and Potential Mechanism(s) of Post-Procedural Rise of Cardiac Biomarker in Patients With Coronary Artery Narrowing After Implantation of an Everolimus-Eluting Bioresorbable Vascular Scaffold or Everolimus-Eluting Metallic Stent

    Ishibashi, Yuki; Muramatsu, Takashi; Nakatani, Shimpei

    2015-01-01

    OBJECTIVES: This study sought to evaluate the mechanism of post-procedural cardiac biomarker (CB) rise following device implantation. BACKGROUND: A fully bioresorbable Absorb scaffold, compared with everolimus-eluting metallic stents (EES), might be associated with a higher incidence...

  12. Cochlear implantation for severe sensorineural hearing loss caused by lightning.

    Myung, Nam-Suk; Lee, Il-Woo; Goh, Eui-Kyung; Kong, Soo-Keun

    2012-01-01

    Lightning strike can produce an array of clinical symptoms and injuries. It may damage multiple organs and cause auditory injuries ranging from transient hearing loss and vertigo to complete disruption of the auditory system. Tympanic-membrane rupture is relatively common in patients with lightning injury. The exact pathogenetic mechanisms of auditory lesions in lightning survivors have not been fully elucidated. We report the case of a 45-year-old woman with bilateral profound sensorineural hearing loss caused by a lightning strike, who was successfully rehabilitated after a cochlear implantation. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Magnetoresistive nanojunctions fabricated via focused ion beam implantation

    Stefanescu, E.; Hong, J.; Guduru, R. [Florida International University (United States); Lavrenov, A. [Hitachi Research (United States); Litvinov, D. [University of Houston, Center for Nanomagnetic Systems (United States); Khizroev, S., E-mail: khizroev@fiu.edu [Florida International University (United States)

    2013-01-15

    Focused ion beam (FIB) is used to implant Ga{sup +} ions into a 30-nm thick magnetoresistive element to effectively reduce the track width of the sensor from 1 Micro-Sign m to {approx}80 nm. Through magnetic recording industry-standard spinstand measurements, it is confirmed that a dose of {approx}10{sup 3} ions/cm{sup 2} at a 1-pA FIB current is sufficient to fully 'de-activate' magnetism in the exposed side regions. To record tracks required for spinstand tests, a FIB-trimmed ring type write head is used.

  14. Body Implanted Medical Device Communications

    Yazdandoost, Kamya Yekeh; Kohno, Ryuji

    The medical care day by day and more and more is associated with and reliant upon concepts and advances of electronics and electromagnetics. Numerous medical devices are implanted in the body for medical use. Tissue implanted devices are of great interest for wireless medical applications due to the promising of different clinical usage to promote a patient independence. It can be used in hospitals, health care facilities and home to transmit patient measurement data, such as pulse and respiration rates to a nearby receiver, permitting greater patient mobility and increased comfort. As this service permits remote monitoring of several patients simultaneously it could also potentially decrease health care costs. Advancement in radio frequency communications and miniaturization of bioelectronics are supporting medical implant applications. A central component of wireless implanted device is an antenna and there are several issues to consider when designing an in-body antenna, including power consumption, size, frequency, biocompatibility and the unique RF transmission challenges posed by the human body. The radiation characteristics of such devices are important in terms of both safety and performance. The implanted antenna and human body as a medium for wireless communication are discussed over Medical Implant Communications Service (MICS) band in the frequency range of 402-405MHz.

  15. Cochlear implants and medical tourism.

    McKinnon, Brian J; Bhatt, Nishant

    2010-09-01

    To compare the costs of medical tourism in cochlear implant surgery performed in India as compared to the United States. In addition, the cost savings of obtaining cochlear implant surgery in India were compare d to those of other surgical interventions obtained as a medical tourist. Searches were conducted on Medline and Google using the search terms: 'medical tourism', 'medical offshoring', 'medical outsourcing', 'cochlear implants' and 'cochlear implantation'. The information regarding cost of medical treatment was obtained from personal communication with individuals familiar with India's cochlear implantation medical tourism industry. The range of cost depended on length of stay as well as the device chosen. Generally the cost, inclusive of travel, surgery and device, was in the range of $21,000-30,000, as compared to a cost range of $40,000-$60,000 in the US. With the escalating cost of healthcare in the United States, it is not surprising that some patients would seek to obtain surgical care overseas at a fraction of the cost. Participants in medical tourism often have financial resources, but lack health insurance coverage. While cardiovascular and orthopedic surgery performed outside the United States in India at centers that cater to medical tourists are often performed at one-quarter to one-third of the cost that would have been paid in the United States, the cost differential for cochlear implants is not nearly as favorable.

  16. Implantation damage in silicon devices

    Nicholas, K.H.

    1977-01-01

    Ion implantation, is an attractive technique for producing doped layers in silicon devices but the implantation process involves disruption of the lattice and defects are formed, which can degrade device properties. Methods of minimizing such damage are discussed and direct comparisons made between implantation and diffusion techniques in terms of defects in the final devices and the electrical performance of the devices. Defects are produced in the silicon lattice during implantation but they are annealed to form secondary defects even at room temperature. The annealing can be at a low temperature ( 0 C) when migration of defects in silicon in generally small, or at high temperature when they can grow well beyond the implanted region. The defect structures can be complicated by impurity atoms knocked into the silicon from surface layers by the implantation. Defects can also be produced within layers on top of the silicon and these can be very important in device fabrication. In addition to affecting the electrical properties of the final device, defects produced during fabrication may influence the chemical properties of the materials. The use of these properties to improve devices are discussed as well as the degradation they can cause. (author)

  17. The vestibular implant: Quo vadis?

    Raymond eVan De Berg

    2011-08-01

    Full Text Available AbstractObjective: to assess the progress of the development of the vestibular implant and its feasibility short-term. Data sources: a search was performed in Pubmed, Medline and Embase. Key words used were vestibular prosth* and vestibular implant. The only search limit was language: English or Dutch. Additional sources were medical books, conference lectures and our personal experience with per-operative vestibular stimulation in patients selected for cochlear implantation.Study selection: all studies about the vestibular implant and related topics were included and evaluated by two reviewers. No study was excluded since every study investigated different aspects of the vestibular implant. Data extraction and synthesis: data was extracted by the first author from selected reports, supplemented by additional information, medical books conference lectures. Since each study had its own point of interest with its own outcomes, it was not possible to compare data of different studies. Conclusion: to use a basic vestibular implant in humans seems feasible in the very near future. Investigations show that electric stimulation of the canal nerves induces a nystagmus which corresponds to the plane of the canal which is innervated by the stimulated nerve branch. The brain is able to adapt to a higher baseline stimulation, while still reacting on a dynamic component. The best response will be achieved by a combination of the optimal stimulus (stimulus profile, stimulus location, precompensation, complemented by central vestibular adaptation. The degree of response will probably vary between individuals, depending on pathology and their ability to adapt.

  18. Imaging of common breast implants and implant-related complications: A pictorial essay.

    Shah, Amisha T; Jankharia, Bijal B

    2016-01-01

    The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  19. Why are mini-implants lost: the value of the implantation technique!

    Romano, Fabio Lourenço; Consolaro, Alberto

    2015-01-01

    The use of mini-implants have made a major contribution to orthodontic treatment. Demand has aroused scientific curiosity about implant placement procedures and techniques. However, the reasons for instability have not yet been made totally clear. The aim of this article is to establish a relationship between implant placement technique and mini-implant success rates by means of examining the following hypotheses: 1) Sites of poor alveolar bone and little space between roots lead to inadequate implant placement; 2) Different sites require mini-implants of different sizes! Implant size should respect alveolar bone diameter; 3) Properly determining mini-implant placement site provides ease for implant placement and contributes to stability; 4) The more precise the lancing procedures, the better the implant placement technique; 5) Self-drilling does not mean higher pressures; 6) Knowing where implant placement should end decreases the risk of complications and mini-implant loss.

  20. Why are mini-implants lost: The value of the implantation technique!

    Fabio Lourenço Romano

    2015-02-01

    Full Text Available The use of mini-implants have made a major contribution to orthodontic treatment. Demand has aroused scientific curiosity about implant placement procedures and techniques. However, the reasons for instability have not yet been made totally clear. The aim of this article is to establish a relationship between implant placement technique and mini-implant success rates by means of examining the following hypotheses: 1 Sites of poor alveolar bone and little space between roots lead to inadequate implant placement; 2 Different sites require mini-implants of different sizes! Implant size should respect alveolar bone diameter; 3 Properly determining mini-implant placement site provides ease for implant placement and contributes to stability; 4 The more precise the lancing procedures, the better the implant placement technique; 5 Self-drilling does not mean higher pressures; 6 Knowing where implant placement should end decreases the risk of complications and mini-implant loss.

  1. Imaging of common breast implants and implant-related complications: A pictorial essay

    Amisha T Shah

    2016-01-01

    Full Text Available The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  2. Implantate in der Augenheilkunde

    Dresp, Joachim H.

    Im Bereich der Augenheilkunde findet sich die weltweit am häufigsten ausgeführte chirurgische Massnahme, die operative Behandlung des Grauen Stars: die Katarakt. Bei der Katarakt handelt es sich um eine Eintrübung der natürlichen Augenlinse, die sich je nach Stadium der Erkrankung leicht opak, über milchig bis zu bräunlich präsentiert. Mit dieser Zunahme der Undurchlässigkeit für das sichtbare Licht geht eine Abnahme des Sehvermögens einher, die bis zur totalen Erblindung führen kann. Bedingt durch die sehr eingeschränkten chirurgischen Möglichkeiten in den Ländern der Dritten Welt ist die Katarakt die Erblindungsursache Nummer 1 in der Welt. Ganz im Gegensatz hierzu ist in den industrialisierten Ländern Europas, Amerikas und Asiens die Katarakt-OP die sicherste chirurgische Intervention. In der Augenheilkunde werden Implantate aller drei Aggregatszustände verwendet.

  3. Precision of fit between implant impression coping and implant replica pairs for three implant systems.

    Nicoll, Roxanna J; Sun, Albert; Haney, Stephan; Turkyilmaz, Ilser

    2013-01-01

    The fabrication of an accurately fitting implant-supported fixed prosthesis requires multiple steps, the first of which is assembling the impression coping on the implant. An imprecise fit of the impression coping on the implant will cause errors that will be magnified in subsequent steps of prosthesis fabrication. The purpose of this study was to characterize the 3-dimensional (3D) precision of fit between impression coping and implant replica pairs for 3 implant systems. The selected implant systems represent the 3 main joint types used in implant dentistry: external hexagonal, internal trilobe, and internal conical. Ten impression copings and 10 implant replicas from each of the 3 systems, B (Brånemark System), R (NobelReplace Select), and A (NobelActive) were paired. A standardized aluminum test body was luted to each impression coping, and the corresponding implant replica was embedded in a stone base. A coordinate measuring machine was used to quantify the maximum range of displacement in a vertical direction as a function of the tightening force applied to the guide pin. Maximum angular displacement in a horizontal plane was measured as a function of manual clockwise or counterclockwise rotation. Vertical and rotational positioning was analyzed by using 1-way analysis of variance (ANOVA). The Fisher protected least significant difference (PLSD) multiple comparisons test of the means was applied when the F-test in the ANOVA was significant (α=.05). The mean and standard deviation for change in the vertical positioning of impression copings was 4.3 ±2.1 μm for implant system B, 2.8 ±4.2 μm for implant system R, and 20.6 ±8.8 μm for implant system A. The mean and standard deviation for rotational positioning was 3.21 ±0.98 degrees for system B, 2.58 ±1.03 degrees for system R, and 5.30 ±0.79 degrees for system A. The P-value for vertical positioning between groups A and B and between groups A and R was <.001. No significant differences were found for

  4. The effects of a slow release GnRH agonist implant on male rabbits

    Goericke-Pesch, Sandra Kathrin; Groeger, Gesa; Wehrend, Axel

    2015-01-01

    Surgical castration is done in male pet rabbits for reproduction control, to reduce inter-male aggression and to control hyper-sexuality, territory marking and aggression against humans. Alternatives to surgical castration are requested because of a relatively great anaesthetic risk in rabbits....... Long-term application of a GnRH agonist implant results in a fully reversible "hormonal" castration in male dogs, cats, boars and many other species. Therefore, the present study using New Zealand White hybrid and German Giant rabbits aimed to investigate the effects of a 4.7mg deslorelin implant...

  5. Fully hadronic ttbar cross section measurement with ATLAS detector

    Bertella, C; The ATLAS collaboration

    2011-01-01

    The top quark pair production cross section in the fully hadronic final state is characterized by a six jet topology, two of which could be identified as originating from a b-quark using ATLAS b-tagging algorithms. Compared to other decay channels, this final state presents an advantageous larger branching ratio; on the other hand it suffers from a very large QCD multi-jet background, generally difficult to estimate from Monte Carlo simulation and therefore evaluated using data-driven techniques. It is essential, to efficiently trigger on these fully hadronic ttbar events, to use dedicated triggers. An overview of the analysis for ttbar production cross section measurement in the fully hadronic final state and the state-of-the-art of the b-jet trigger performance estimation are presented in this contribution.

  6. Fully kinetic simulations of megajoule-scale dense plasma focus

    Schmidt, A.; Link, A.; Tang, V.; Halvorson, C.; May, M. [Lawrence Livermore National Laboratory, Livermore California 94550 (United States); Welch, D. [Voss Scientific, LLC, Albuquerque, New Mexico 87108 (United States); Meehan, B. T.; Hagen, E. C. [National Security Technologies, LLC, Las Vegas, Nevada 89030 (United States)

    2014-10-15

    Dense plasma focus (DPF) Z-pinch devices are sources of copious high energy electrons and ions, x-rays, and neutrons. Megajoule-scale DPFs can generate 10{sup 12} neutrons per pulse in deuterium gas through a combination of thermonuclear and beam-target fusion. However, the details of the neutron production are not fully understood and past optimization efforts of these devices have been largely empirical. Previously, we reported on the first fully kinetic simulations of a kilojoule-scale DPF and demonstrated that both kinetic ions and kinetic electrons are needed to reproduce experimentally observed features, such as charged-particle beam formation and anomalous resistivity. Here, we present the first fully kinetic simulation of a MegaJoule DPF, with predicted ion and neutron spectra, neutron anisotropy, neutron spot size, and time history of neutron production. The total yield predicted by the simulation is in agreement with measured values, validating the kinetic model in a second energy regime.

  7. Fully plastic solutions of semi-elliptical surface cracks

    Yagawa, Genki; Yoshimura, Shinobu; Kitajima, Yasumi; Ueda, Hiroyoshi.

    1990-01-01

    Nonlinear finite element analyses of semi-elliptical surface cracks are performed under the fully plastic condition. The power-law hardening materials and the deformation theory of plasticity are assumed. Either the penalty function method or the Uzawa's algorithm is utilized to treat the incompressibility of plastic strains. The local and global J-integral values are obtained using a virtual crack extension technique for plates and cylinders with semi-elliptical surface cracks subjected to uniform tensions. The fully plastic solutions for surface cracked plates are given in the form of polynominals with geometric parameters a/t, a/c and the strain hardening exponent (n). In addition, the effects of curvature on fully plastic solutions are discussed through the comparison between the results of plates and cylinders. (author)

  8. CMOS serial link for fully duplexed data communication

    Lee, Kyeongho; Kim, Sungjoon; Ahn, Gijung; Jeong, Deog-Kyoon

    1995-04-01

    This paper describes a CMOS serial link allowing fully duplexed 500 Mbaud serial data communication. The CMOS serial link is a robust and low-cost solution to high data rate requirements. A central charge pump PLL for generating multiphase clocks for oversampling is shared by several serial link channels. Fully duplexed serial data communication is realized in the bidirectional bridge by separating incoming data from the mixed signal on the cable end. The digital PLL accomplishes process-independent data recovery by using a low-ratio oversampling, a majority voting, and a parallel data recovery scheme. Mostly, digital approach could extend its bandwidth further with scaled CMOS technology. A single channel serial link and a charge pump PLL are integrated in a test chip using 1.2 micron CMOS process technology. The test chip confirms upto 500 Mbaud unidirectional mode operation and 320 Mbaud fully duplexed mode operation with pseudo random data patterns.

  9. Fully developed turbulence via Feigenbaum's period-doubling bifurcations

    Duong-van, M.

    1987-08-01

    Since its publication in 1978, Feigenbaum's predictions of the onset of turbulence via period-doubling bifurcations have been thoroughly borne out experimentally. In this paper, Feigenbaum's theory is extended into the regime in which we expect to see fully developed turbulence. We develop a method of averaging that imposes correlations in the fluctuating system generated by this map. With this averaging method, the field variable is obtained by coarse-graining, while microscopic fluctuations are preserved in all averaging scales. Fully developed turbulence will be shown to be a result of microscopic fluctuations with proper averaging. Furthermore, this model preserves Feigenbaum's results on the physics of bifurcations at the onset of turbulence while yielding additional physics both at the onset of turbulence and in the fully developed turbulence regime

  10. Falha prematura em implantes orais = Early oral implant failures

    Fadanelli, Alexandro Bianchi

    2005-01-01

    Full Text Available Atualmente, ainda há uma percentagem significativa de fracassos de implantes na prática clínica, causando transtorno para o profissional e para o paciente. O objetivo deste estudo foi avaliar a bibliografia disponível sobre o assunto, apresentar um caso clínico e discutir os aspectos relacionados aos insucessos na terapia com implantes ocorridos durante o período de osteointegração. A avaliação da literatura mostrou haverem múltiplos fatores possivelmente envolvidos nas falhas de implantes, sendo que através do estudo das falhas pode-se minimizar sua ocorrência

  11. Medical implants and methods of making medical implants

    Shaw, Wendy J; Yonker, Clement R; Fulton, John L; Tarasevich, Barbara J; McClain, James B; Taylor, Doug

    2014-09-16

    A medical implant device having a substrate with an oxidized surface and a silane derivative coating covalently bonded to the oxidized surface. A bioactive agent is covalently bonded to the silane derivative coating. An implantable stent device including a stent core having an oxidized surface with a layer of silane derivative covalently bonded thereto. A spacer layer comprising polyethylene glycol (PEG) is covalently bonded to the layer of silane derivative and a protein is covalently bonded to the PEG. A method of making a medical implant device including providing a substrate having a surface, oxidizing the surface and reacting with derivitized silane to form a silane coating covalently bonded to the surface. A bioactive agent is then covalently bonded to the silane coating. In particular instances, an additional coating of bio-absorbable polymer and/or pharmaceutical agent is deposited over the bioactive agent.

  12. An Unusual Bone Loss Around Implants

    Amirreza Rokn

    2013-01-01

    Full Text Available AbstractPre-implant disease is an inflammatory process, which can affect the surrounding tissues of a functional Osseointegrated implant that is usually as a result of a disequilibrium between the micro-flora and the body defense system.This case reports a 57 years old male with unusual bone loss around dental implants.This was an unusual case of peri-implantitis which occurred only in the implants on one side of the mouth although they all were unloaded implants.

  13. Occlusal considerations for dental implant restorations.

    Bergmann, Ranier H

    2014-01-01

    When placed, dental implants are put into an ever-changing oral environment in which teeth can continue to migrate. Yet, the implants themselves are ankylosed. This can lead to occlusal instability. Teeth may continue to erupt, leaving the implants in infraocclusion. Teeth may move mesially away from an implant, requiring modification to close an open contact point. Friction in the connection between teeth and implants can lead to intrusion of teeth and damage to the periodontal attachment apparatus. Implant occlusion with shallow incisal guidance minimizes lateral and tipping forces. Cross-arch stabilization allows the best distribution of occlusal forces. The choice of restorative materials influences long-term occlusal stability.

  14. Hexagonal undersampling for faster MRI near metallic implants.

    Sveinsson, Bragi; Worters, Pauline W; Gold, Garry E; Hargreaves, Brian A

    2015-02-01

    Slice encoding for metal artifact correction acquires a three-dimensional image of each excited slice with view-angle tilting to reduce slice and readout direction artifacts respectively, but requires additional imaging time. The purpose of this study was to provide a technique for faster imaging around metallic implants by undersampling k-space. Assuming that areas of slice distortion are localized, hexagonal sampling can reduce imaging time by 50% compared with conventional scans. This work demonstrates this technique by comparisons of fully sampled images with undersampled images, either from simulations from fully acquired data or from data actually undersampled during acquisition, in patients and phantoms. Hexagonal sampling is also shown to be compatible with parallel imaging and partial Fourier acquisitions. Image quality was evaluated using a structural similarity (SSIM) index. Images acquired with hexagonal undersampling had no visible difference in artifact suppression from fully sampled images. The SSIM index indicated high similarity to fully sampled images in all cases. The study demonstrates the ability to reduce scan time by undersampling without compromising image quality. © 2014 Wiley Periodicals, Inc.

  15. Fully simulatable quantum-secure coin-flipping and applications

    Lunemann, Carolin; Nielsen, Jesper Buus

    2011-01-01

    schemes which we show how to construct in the given setting. We then show that the interactive generation of random coins at the beginning or during outer protocols allows for quantum-secure realizations of classical schemes, again without any set-up assumptions. As example applications we discuss quantum...... zero-knowledge proofs of knowledge and quantum-secure two-party function evaluation. Both applications assume only fully simulatable coin-flipping and mixed commitments. Since our framework allows to construct fully simulatable coin-flipping from mixed commitments, this in particular shows that mixed...

  16. Design Study of Fully Superconducting Wind Turbine Generators

    Song, Xiaowei (Andy); Mijatovic, Nenad; Jensen, Bogi Bech

    2015-01-01

    In this paper, two fully superconducting generators employing MgB2 armature winding, with YBCO and MgB2 field winding respectively, are presented and analyzed. The ac loss in armature winding is estimated, and a simple comparative study is carried out. The results show that both electromagnetic...... designs for fully superconducting generators are promising with respect to the power density. However, the cost of removing ac loss in armature winding is as high as $900 000. It is also noted that with the current price of YBCO tape, the generator employing MgB 2 field winding would have lower cost....

  17. A new memory effect (MSD) in fully depleted SOI MOSFETs

    Bawedin, M.; Cristoloveanu, S.; Yun, J. G.; Flandre, D.

    2005-09-01

    We demonstrate that the transconductance and drain current of fully depleted MOSFETs can display an interesting time-dependent hysteresis. This new memory effect, called meta-stable dip (MSD), is mainly due to the long carrier generation lifetime in the silicon film. Our parametric analysis shows that the memory window can be adjusted in view of practical applications. Various measurement conditions and devices with different doping, front oxide and silicon film thicknesses are systematically explored. The MSD effect can be generalized to several fully depleted CMOS technologies. The MSD mechanism is discussed and validated by two-dimensional simulations results.

  18. Current trends in ion implantation

    Gwilliam, R.M.

    2001-01-01

    As semiconductor device dimensions continue to shrink, the drive beyond 250 nm is creating significant problems for the device processor. In particular, trends toward shallower-junctions, lower thermal budgets and simplified processing steps present severe challenges to ion implantation. In parallel with greater control of the implant process goes the need for a better understanding of the physical processes involved during implantation and subsequent activation annealing. For instance, the need for an understanding of dopant-defect interaction is paramount as defects mediate a number of technologically important phenomena such as transient enhanced diffusion and impurity gettering. This paper will outline the current trends in the ion implantation and some of the challenges it faces in the next decade, as described in the semiconductor roadmap. It will highlight some recent positron annihilation work that has made a contribution to addressing one of these challenges, namely the need for tighter control of implant uniformity and dose. Additionally, some vacancy-mediated processes are described with the implication that these may provide areas in which positron annihilation spectroscopy could make a significant contribution. (orig.)

  19. Composite fibrous glaucoma drainage implant

    Klapstova, A.; Horakova, J.; Shynkarenko, A.; Lukas, D.

    2017-10-01

    Glaucoma is a frequent reason of loss vision. It is usually caused by increased intraocular pressure leading to damage of optic nerve head. This work deals with the development of fibrous structure suitable for glaucoma drainage implants (GDI). Commercially produced metallic glaucoma implants are very effective in lowering intraocular pressure. However, these implants may cause adverse events such as damage to adjacent tissue, fibrosis, hypotony or many others [1]. The aim of this study is to reduce undesirable properties of currently produced drains and improve their properties by creating of the composite fibrous drain for achieve a normal intraocular pressure. Two types of electrospinning technologies were used for the production of very small tubular implants. First type was focused for production of outer part of tubular drain and the second type of electrospinning method made the inner part of shape follows the connections of both parts. Complete implant had a special properties suitable for drainage of fluid. Morphological parameters, liquid transport tests and in-vitro cell adhesion tests were detected.

  20. Cranioplasty with individual titanium implants

    Mishinov, S.; Stupak, V.; Sadovoy, M.; Mamonova, E.; Koporushko, N.; Larkin, V.; Novokshonov, A.; Dolzhenko, D.; Panchenko, A.; Desyatykh, I.; Krasovsky, I.

    2017-09-01

    Cranioplasty is the second procedure in the history of neurosurgery after trepanation, and it is still relevant despite the development of civilization and progress in medicine. Each cranioplasty operation is unique because there are no two patients with identical defects of the skull bones. The development of Direct Metal Laser Sintering (DMLS) technique opened up the possibility of direct implant printing of titanium, a biocompatible metal used in medicine. This eliminates the need for producing any intermediate products to create the desired implant. We have produced 8 patient-specific titanium implants using this technique for patients who underwent different decompressive cranioectomies associated with bone tumors. Follow-up duration ranged from 6 to 12 months. We observed no implant-related reactions or complications. In all cases of reconstructive neurosurgery we achieved good clinical and aesthetic results. The analysis of the literature and our own experience in three-dimensional modeling, prototyping, and printing suggests that direct laser sintering of titanium is the optimal method to produce biocompatible surgical implants.

  1. Aqueous shunt implantation in glaucoma

    Jing Wang

    2017-01-01

    Full Text Available Aqueous shunts or glaucoma drainage devices are increasingly utilized in the management of refractory glaucoma. The general design of the most commonly-used shunts is based on the principles of the Molteno implant: ie. a permanent sclerostomy (tube, a predetermined bleb area (plate and diversion of aqueous humour to the equatorial region and away from the limbal subconjunctival space. These three factors make aqueous shunts more resistant to scarring as compared to trabeculectomy. The two most commonly used shunts are the Ahmed Glaucoma Valve, which contains a flow-restrictor, and the non-valved Baervedlt Glaucoma Implant. While the valved implants have a lower tendency to hypotony and related complications, the non-valved implants with larger, more-biocompatible end plate design, achieve lower intraocular pressures with less encapsulation. Non-valved implants require additional suturing techniques to prevent early hypotony and a number of these methods will be described. Although serious shunt-related infection is rare, corneal decompensation and diplopia are small but significant risks.

  2. Capacitive Feedthroughs for Medical Implants.

    Grob, Sven; Tass, Peter A; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging.

  3. A new system of implant abutment connection: how to improve a two piece implant system sealing.

    Grecchi, F; DI Girolamo, M; Cura, F; Candotto, V; Carinci, F

    2017-01-01

    Implant dentistry has become one of the most successful dentistry techniques for replacing missing teeth. The success rate of implant dentistry is above 80%. However, peri-implantitis is a later complication of implant dentistry that if untreated, can lead to implant loss. One of the hypotized causes of peri-implantis is the bacterial leakage at the level of implant-abutment connection. Bacterial leakage is favored to the presence of a micro gap at the implant-abutment interface, allowing microorganisms to penetrate and colonize the inner part of the implant leading to biofilm accumulation and consequently to peri-implantitis development. To identify the capability of the implant to protect the internal space from the external environment, the passage of genetically modified Escherichia coli across implant-abutment interface was evaluated. Implants were immerged in a bacterial culture for twenty-four hours and then bacteria amount was measured inside implant-abutment interface with Real-time PCR. Bacteria were detected inside all studied implants, with a median percentage of 9%. The reported results are better to those of previous studies carried out on different implant systems. Until now, none implant-abutment system has been proven to seal the gap between implant and abutment.

  4. Physico-Chemical and Biochemical Characteristics of Mixed Saliva in Patients at Various Time After Dental Implantation

    Zekiy A.O.

    2015-12-01

    Full Text Available he study deals with comparison of physico-chemical (pH, buffer capacity, viscosity and biochemical (concentration of albumin, calcium, phosphate, the activity of aamylase and alkaline phosphatase variables in the mixed saliva (oral fluid, OF in persons with dental implants depending on its number (1-2 or 3 and more and time after installation (2-4 and 5-11 months, and those with satisfactory state of oral health and without implants. The pH value in OF was almost similar in patients of group comparison and at different times after implantation and at different number of implants. The OF buffer capacity in different periods after the installation of single implants varied, been typical for the comparison group. A 2.4-fold decrease of buffer capacity was character at 2-4 months after installation of three or more implants, later this decline has not recovered fully. The installation of a single implant was not accompanied by changes in the OF viscosity, while multiple dental implant installation let to increase of viscosity 2.1 times less than in the comparison group at 2-4 months terms. The alterations of some biochemical properties of OF after dental implantation were shown to depend on the number and timing since the load on the installed constructions. Thus, more significant changes in oral fluid are to reduce the buffer capacity and viscosity of oral fluid, the concentration of calcium ions and the activity of a-amylase, they may be stored at the time of 5-11 months after implantation. These changes are associated with possible functional properties of oral fluid, which may affect the adaptation of dental system to new functional conditions connected to dental implant installation.

  5. Evolution of voids in Al+-implanted ZnO probed by a slow positron beam

    Chen, Z.Q.; Maekawa, M.; Yamamoto, S.; Kawasuso, A.; Yuan, X.L.; Sekiguchi, T.; Suzuki, R.; Ohdaira, T.

    2004-01-01

    Undoped ZnO single crystals were implanted with aluminum ions up to a dose of 10 15 Al + /cm 2 . Vacancy defects in the implanted layers were detected using positron lifetime and Doppler broadening measurements with slow positron beams. It shows that vacancy clusters, which are close to the size of V 8 , are generated by implantation. Postimplantation annealing shows that the Doppler broadening S parameter increases in the temperature range from 200 deg. C to 600 deg. C suggesting further agglomeration of vacancy clusters to voids. Detailed analyses of Doppler broadening spectra show formation of positronium after 600 deg. C annealing of the implanted samples with doses higher than 10 14 Al + /cm 2 . Positron lifetime measurements further suggest that the void diameter is about 0.8 nm. The voids disappear and the vacancy concentration reaches the detection limit after annealing at 600-900 deg. C. Hall measurement shows that the implanted Al + ions are fully activated with improved carrier mobility after final annealing. Cathodoluminescence measurements show that the ultraviolet luminescence is much stronger than the unimplanted state. These findings also suggest that the electrical and optical properties of ZnO become much better by Al + implantation and subsequent annealing

  6. Application of micro beam PIXE to detection of titanium ion release from dental and orthopaedic implants

    Ektessabi, A.M.; Otsuka, T.; Tsuboi, Y.; Yokoyama, K.; Albrektsson, T.; Sennerby, L.; Johansson, C.

    1994-01-01

    In the past two decades the utilization of dental and orthopaedic implants in reconstructive surgery has been spread widely. Most of these implants are inserted in the corrosive environment of the human body for long periods of time. The level of dissolution, release, and transport of metal ions as a result of corrosion of these materials are not fully known at present. We report the results of application of micro ion beam PIXE spectroscopy to detect release of titanium from titanium and titanium alloy implants inserted in the tibiae of rabbits for three months. It was found that titanium ions could be detected in the surrounding tissues, with high precision, as a gradient from the implant surface and in higher amounts in the bone tissue as compared with the soft tissues. It is concluded that application of micro ion beam PIXE spectroscopy for detection of metal ion release, and distribution of the released material around the implants with high special resolution and accuracy may be used to further investigate the mechanism of metal release, and the relation between surface micromorphology and corrosion resistance of the implant materials. (author)

  7. Ion implantation enhanced metal-Si-metal photodetectors

    Sharma, A. K.; Scott, K. A. M.; Brueck, S. R. J.; Zolper, J. C.; Myers, D. R.

    1994-05-01

    The quantum efficiency and frequency response of simple Ni-Si-Ni metal-semiconductor-metal (MSM) photodetectors at long wavelengths are significantly enhanced with a simple, ion-implantation step to create a highly absorbing region approx. 1 micron below the Si surface. The internal quantum efficiency is improved by a factor of approx. 3 at 860 nm (to 64%) and a full factor of ten at 1.06 microns (to 23%) as compared with otherwise identical unimplanted devices. Dark currents are only slightly affected by the implantation process and are as low as 630 pA for a 4.5-micron gap device at 10-V bias. Dramatic improvement in the impulse response is observed, 100 ps vs. 600 ps, also at 10-V bias and 4.5-micron gap, due to the elimination of carrier diffusion tails in the implanted devices. Due to its planar structure, this device is fully VLSI compatible. Potential applications include optical interconnections for local area networks and multi-chip modules.

  8. Theoretical predictions of the lateral spreading of implanted ions

    Ashworth, D.G.; Oven, R.

    1986-01-01

    The theoretical model and computer program (AAMPITS-3D) of Ashworth and co-workers for the calculation of three-dimensional distributions of implanted ions in multi-element amorphous targets are extended to show that the lateral rest distribution is gaussian in a form with a lateral standard deviation (lateral-spread function) which is a function of depth beneath the target surface. A method is given whereby this function may be accurately determined from a knowledge of the projected range and chord range rest distribution functions. Examples of the lateral-spread function are given for boron, phosphorus and arsenic ions implanted into silicon and a detailed description is given of how the lateral-spread function may be used in conjunction with the projected range rest distribution function to provide a fully three-dimensional rest distribution of ions implanted into amorphous targets. Examples of normalised single ion isodensity contours computed from AMPITS-3D are compared with those obtained using the previous assumption of a lateral standard deviation which was independent of distance beneath the target surface. (author)

  9. Cortical Plasticity after Cochlear Implantation

    Petersen, Bjørn; Gjedde, Albert; Wallentin, Mikkel

    2013-01-01

    recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners...... with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss...... occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only...

  10. Tinting of intraocular lens implants

    Zigman, S.

    1982-06-01

    Intraocular lens (IOL) implants of polymethyl methacrylate (PMMA) lack an important yellow pigment useful as a filter in the visual process and in the protection of the retina from short-wavelength radiant energy. The ability to produce a yellow pigment in the PMMA used in IOL implants by exposure to near-ultraviolet (UV) light was tested. It was found that the highly cross-linked material in Copeland lens blanks was tinted slightly because of this exposure. The absorptive properties of lens blanks treated with near-UV light in this way approached that of the absorptive properties of human lenses. This finding shows that it is possible to alter IOL implants simply so as to induce a pale-yellow pigment in them to improve the visual process and to protect the retinas of IOL users.

  11. MRI of orbital hydroxyapatite implants

    Flanders, A.E.; De Potter P.; Rao, V.M.; Tom, B.M.; Shields, C.L.; Shields, J.A.

    1996-01-01

    Our aim was to use MRI for the postsurgical assessment of a new form of integrated orbital implant composed of a porous calcium phosphate hydroxyapatite substrate. We studied ten patients 24-74 years of age who underwent enucleation and implantation of a hydroxyapatite ball; 5-13 months after surgery, each patient was examined by spin-echo MRI, with fat suppression and gadolinium enhancement. Fibrovascular ingrowth was demonstrated in all ten patients as areas of enhancement at the periphery of the hydroxyapatite sphere that extended to the center to a variable degree. The radiologist should aware of the MRI appearances of the coralline hydroxyapatite orbital implant since it is now widely used following enucleation. MRI is a useful means to determine successful incorporation of the substrate into the orbital tissues. The normal pattern of contrast enhancement should not be mistaken for recurrent tumor or infection. (orig.)

  12. Tinting of intraocular lens implants

    Zigman, S.

    1982-01-01

    Intraocular lens (IOL) implants of polymethyl methacrylate (PMMA) lack an important yellow pigment useful as a filter in the visual process and in the protection of the retina from short-wavelength radiant energy. The ability to produce a yellow pigment in the PMMA used in IOL implants by exposure to near-ultraviolet (UV) light was tested. It was found that the highly cross-linked material in Copeland lens blanks was tinted slightly because of this exposure. The absorptive properties of lens blanks treated with near-UV light in this way approached that of the absorptive properties of human lenses. This finding shows that it is possible to alter IOL implants simply so as to induce a pale-yellow pigment in them to improve the visual process and to protect the retinas of IOL users

  13. Implant rehabilitation in bruxism patient

    Goiato, Marcelo Coelho; Sonego, Mariana Vilela; dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

    2014-01-01

    A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocols supported by six implants in each arch were installed after a 6-month healing period. A soft occlusal splint was made due to the patient's history of bruxism, and the lack of its use by the patient resulted in an acrylic fracture. The prosthesis was repaired and the importance of using the occlusal splint was restated. In the 4-year follow-up no fractures were reported. PMID:24907215

  14. MR imaging of breast implants.

    Gorczyca, D P

    1994-11-01

    MR imaging has proved to be an excellent imaging modality in locating free silicone and evaluating an implant for rupture, with a sensitivity of approximately 94% and specificity of 97%. Silicone has a unique MR resonance frequency and long T1 and T2 relaxation times, which allows several MR sequences to provide excellent diagnostic images. The most commonly used sequences include T2-weighted, STIR, and chemical shift imaging (Figs. 3, 13, and 14). The T2-weighted and STIR sequences are often used in conjunction with chemical water suppression. The most reliable findings on MR images for detection of implant rupture include identification of the collapsed implant shell (linguine sign) and free silicone within the breast parenchyma.

  15. Radioactive implants for medical applications; Radioaktive Implantate fuer medizinische Anwendungen

    Schubert, M.

    2008-07-01

    The long-term success of surgery is often diminished by excessive wound healing, which makes another intervention necessary. Locally applied radionuclides with short range radiation can prevent such benign hyperproliferation. As pure electron emitter with a half-life of 14.3 days and a mean energy of 694.9 keV (E{sub max}=1710.48 keV) {sup 32}P is a suitable radionuclide which can be produced from the stable {sup 31}P by the capture of thermal neutrons (1 x 10{sup 14} /s/cm{sup 2}) in a nuclear reactor. After a typical irradiation time (14 days) the ratio of {sup 32}P to {sup 31}P is 1.4 x 10{sup -5} to 1. Implants made of polymer and/or bioabsorbable material functioning as a carrier of the radioactive emitter allow - as opposed to metallic implants - for new applications for this type of radiotherapy. In this thesis a manufacturing method for previously not available organic, radioactive implants has been developed and a corresponding dosimetry system has been established. By means of ion implantation, {sup 32}P ions with up to 180 keV can be shot some 100 nm deep into organic implant materials. For a typical dose (15 Gy over 7 days, 1 mm distance from the implant) an activity of 75 kBq is needed corresponding to 1.3 x 10{sup 11} {sup 32}P ions. The sputter ion gun, which has been optimized for this application, creates an ion beam with high beam current (> 14 {mu}A P{sup -}) and low emittance (< 4 {pi} mm mrad {radical}(MeV)). Because of the good beam quality also small implants (<1 mm{sup 2}) can be manufactured with high efficiency. The unintentionally co-implanted portion of molecules and nuclides of the same mass (e.g. {sup 31}PH, {sup 16}O{sub 2} and {sup 32}S) could be reduced from approximately 500 to 50 by an improvement of the isotope selection at {sup 32}P beam creation. Hence, in comparison with the best hitherto existing implantation methods, the radiation dose of the implant could be reduced by an order of magnitude. With regard to the beta

  16. Development of a fully injectable calcium phosphate cement

    Permanent link: https://www.ias.ac.in/article/fulltext/boms/026/04/0415-0422. Keywords. Calcium phosphate cements; hydroxyapatite; bioceramics; bone substitute; orthopedic; dental. Abstract. A study on the development of a fully injectable calcium phosphate cement for orthopedic and dental applications is presented.

  17. 7 CFR 635.4 - Failure to fully comply.

    2010-01-01

    ... to participants who are determined by the Chief to have made a good faith effort to comply fully with... whether a participant acted in good faith and rendered substantial performance under paragraph (b) of this..., the Chief, or designee, may grant relief in accordance with § 635.5 if the participant made a good...

  18. Peirce and Rationalism: Is Peirce a Fully Semiotic Philosopher?

    Stables, Andrew

    2014-01-01

    While Peirce is a seminal figure for contemporary semiotic philosophers, it is axiomatic of a fully semiotic perspective that no philosopher or philosophy (semiotics included) can provide any final answer, as signs are always interpreted and the context of interpretation always varies. Semiosis is evolutionary: it may or may not be construed as…

  19. SYSTEMATIZATION AND ANALYSIS OF PARTIALLY AND FULLY HOMOMORPHIC CRYPTOSYSTEM

    A. V. Epishkina

    2016-12-01

    Full Text Available In this article provides an overview of the known partially and fully homomorphic cryptosystem, such as: RSA, ElGamal, Paillier, Gentry and Halevi. Justified the homomorphic properties of the considered cryptosystems. The comparative analysis of the homomorphic encryption algorithms has been committed

  20. Viscosity solutions of fully nonlinear functional parabolic PDE

    Liu Wei-an

    2005-01-01

    Full Text Available By the technique of coupled solutions, the notion of viscosity solutions is extended to fully nonlinear retarded parabolic equations. Such equations involve many models arising from optimal control theory, economy and finance, biology, and so forth. The comparison principle is shown. Then the existence and uniqueness are established by the fixed point theory.

  1. A Fully Inkjet Printed 3D Honeycomb Inspired Patch Antenna

    McKerricher, Garret; Titterington, Don; Shamim, Atif

    2015-01-01

    by inkjet printing in this work. This is the first demonstration of a fully 3D Multijet printing process with integrated polymer and metal. A 2.4 GHz patch antenna is successfully fabricated with good performance proving the viability of the process

  2. Design of a Fully-Passive Transfemoral Prosthesis Prototype

    Behrens, Sebastiaan Maria; Behrens, S.M.; Ünal, Ramazan; Unal, R.; Hekman, Edsko E.G.; Carloni, Raffaella; Stramigioli, Stefano; Koopman, Hubertus F.J.M.

    In this study, we present the mechanical design of a prototype of a fully-passive transfemoral prosthesis for normal walking. The conceptual working principle at the basis of the design is inspired by the power flow in human gait, with the main purpose of realizing an energy efficient device. The

  3. Benchmarking of regenerative braking for a fully electric car

    Varocky, B.J.; Nijmeijer, H.; Jansen, S.; Besselink, I.J.M.; Mansvelder, R.; Mansvelders, R.E.

    2011-01-01

    Short range of electric vehicles is one of the stumbling blocks in the way of electric cars to gaining wide user acceptance and becoming a major market player. The possibility to recover vehicle energy otherwise lost as heat during braking is an inherent advantage of a hybrid electric or a fully

  4. A Fully Transparent Resistive Memory for Harsh Environments

    Yang, Po-Kang; Ho, Chih-Hsiang; Lien, Der-Hsien; Duran Retamal, Jose Ramon; Kang, Chen-Fang; Chen, Kuan-Ming; Huang, Teng-Han; Yu, Yueh-Chung; Wu, Chih-I; He, Jr-Hau

    2015-01-01

    A fully transparent resistive memory (TRRAM) based on Hafnium oxide (HfO2) with excellent transparency, resistive switching capability, and environmental stability is demonstrated. The retention time measured at 85 °C is over 3 × 104 sec

  5. Fully probabilistic design: the way for optimizing of concrete structures

    I. Laníková

    Full Text Available Some standards for the design of concrete structures (e.g. EC2 and the original ČSN 73 1201-86 allow a structure to be designed by several methods. This contribution documents the fact that even if a structure does not comply with the partial reliability factor method, according to EC2, it can satisfy the conditions during the application of the fully probabilistic approach when using the same standard. From an example of the reliability of a prestressed spun concrete pole designed by the partial factor method and fully probabilistic approach according to the Eurocode it is evident that an expert should apply a more precise (though unfortunately more complicated method in the limiting cases. The Monte Carlo method, modified by the Latin Hypercube Sampling (LHS method, has been used for the calculation of reliability. Ultimate and serviceability limit states were checked for the partial factor method and fully probabilistic design. As a result of fully probabilistic design it is possible to obtain a more efficient design for a structure.

  6. LV challenge LKEB contribution : fully automated myocardial contour detection

    Wijnhout, J.S.; Hendriksen, D.; Assen, van H.C.; Geest, van der R.J.

    2009-01-01

    In this paper a contour detection method is described and evaluated on the evaluation data sets of the Cardiac MR Left Ventricle Segmentation Challenge as part of MICCAI 2009s 3D Segmentation Challenge for Clinical Applications. The proposed method, using 2D AAM and 3D ASM, performs a fully

  7. A fully integrated 16 channel digitally trimmed pulse shaping amplifier

    Hearn, W.E.; Wright, M.E.

    1993-11-01

    A fully integrated CMOS pulse shaping amplifier has been developed at LBL. All frequency dependent networks are included on the chip. Provision is made for tuning to compensate for process variations. The overall architecture and details of the circuitry are discussed. Test results are presented

  8. New approach to solve symmetric fully fuzzy linear systems

    In this paper, we present a method to solve fully fuzzy linear systems with symmetric coefficient matrix. The symmetric coefficient matrix is decomposed into two systems of equations by using Cholesky method and then a solution can be obtained. Numerical examples are given to illustrate our method.

  9. Surface engineering by ion implantation

    Nielsen, Bjarne Roger

    1995-01-01

    Awidespread commercial applica tion iof particle accelerators is for ion implantation. Accelerator beams are used for ion implantation into metals, alloying a thin surface layer with foreign atoms to concentrations impossible to achieve by thermal processes, making for dramatic improvements in hardness and in resistance to wear and corrosion. Traditional hardening processes require high temperatures causing deformation; ion implantation on the other hand is a ''cold process'', treating the finished product. The ionimplanted layer is integrated in the substrate, avoiding the risk of cracking and delamination from normal coating processes. Surface properties may be ''engineered'' independently of those of the bulk material; the process does not use environmentally hazardous materials such as chromium in the surface coating. The typical implantation dose required for the optimum surface properties of metals is around 2 x 10 17 ion/cm 2 , a hundred times the typical doses for semiconductor processing. When surface areas of more than a few square centimetres have to be treated, the implanter must therefore be able to produce high beam currents (5 to 10 mA) to obtain an acceptable treatment time. Ion species used include nitrogen, boron, carbon, titanium, chromium and tantalum, and beam energies range from 50 to 200 keV. Since most components are three dimensional, it must be possible to rotate and tilt them in the beam, and control beam position over a large area. Examples of industrial applications are: - surface treatment of prostheses (hip and knee joints) to reduce wear of the moving parts, using biocompatible materials; - ion implantation into high speed ball bearings to protect against the aqueous corrosion in jet engines (important for service helicopters on oil rigs); - hardening of metal forming and cutting tools; - reduction of corrosive wear of plastic moulding tools, which are expensive to produce

  10. Carbon Fiber Biocompatibility for Implants

    Richard Petersen

    2016-01-01

    Full Text Available Carbon fibers have multiple potential advantages in developing high-strength biomaterials with a density close to bone for better stress transfer and electrical properties that enhance tissue formation. As a breakthrough example in biomaterials, a 1.5 mm diameter bisphenol-epoxy/carbon-fiber-reinforced composite rod was compared for two weeks in a rat tibia model with a similar 1.5 mm diameter titanium-6-4 alloy screw manufactured to retain bone implants. Results showed that carbon-fiber-reinforced composite stimulated osseointegration inside the tibia bone marrow measured as percent bone area (PBA to a great extent when compared to the titanium-6-4 alloy at statistically significant levels. PBA increased significantly with the carbon-fiber composite over the titanium-6-4 alloy for distances from the implant surfaces of 0.1 mm at 77.7% vs. 19.3% (p < 10−8 and 0.8 mm at 41.6% vs. 19.5% (p < 10−4, respectively. The review focuses on carbon fiber properties that increased PBA for enhanced implant osseointegration. Carbon fibers acting as polymer coated electrically conducting micro-biocircuits appear to provide a biocompatible semi-antioxidant property to remove damaging electron free radicals from the surrounding implant surface. Further, carbon fibers by removing excess electrons produced from the cellular mitochondrial electron transport chain during periods of hypoxia perhaps stimulate bone cell recruitment by free-radical chemotactic influences. In addition, well-studied bioorganic cell actin carbon fiber growth would appear to interface in close contact with the carbon-fiber-reinforced composite implant. Resulting subsequent actin carbon fiber/implant carbon fiber contacts then could help in discharging the electron biological overloads through electrochemical gradients to lower negative charges and lower concentration.

  11. Neutrophil Responses to Sterile Implant Materials.

    Siddharth Jhunjhunwala

    Full Text Available In vivo implantation of sterile materials and devices results in a foreign body immune response leading to fibrosis of implanted material. Neutrophils, one of the first immune cells to be recruited to implantation sites, have been suggested to contribute to the establishment of the inflammatory microenvironment that initiates the fibrotic response. However, the precise numbers and roles of neutrophils in response to implanted devices remains unclear. Using a mouse model of peritoneal microcapsule implantation, we show 30-500 fold increased neutrophil presence in the peritoneal exudates in response to implants. We demonstrate that these neutrophils secrete increased amounts of a variety of inflammatory cytokines and chemokines. Further, we observe that they participate in the foreign body response through the formation of neutrophil extracellular traps (NETs on implant surfaces. Our results provide new insight into neutrophil function during a foreign body response to peritoneal implants which has implications for the development of biologically compatible medical devices.

  12. Fractographic analysis of fractured dental implant components

    Chih-Ling Chang

    2013-03-01

    Conclusion: To avoid implant fracture, certain underlying mechanical risk factors should be noted such as patients with a habit of bruxism, bridgework with a cantilever design, or two implants installed in a line in the posterior mandible.

  13. Production of amorphous alloys by ion implantation

    Grant, W.A.; Chadderton, L.T.; Johnson, E.

    1978-01-01

    Recent data are reported on the use of ion implantation to produce amorphous metallic alloys. In particular data on the dose dependence of the crystalline to amorphous transition induced by P + implantation of nickel is presented. (Auth.)

  14. Dental implant surgery: planning and guidance

    Lobregt, S.; Schillings, J.J.; Vuurberg, E.

    2001-01-01

    A prototype application has been developed for interactive planning of dental implants on the EasyVision workstation. The user is led step by step via virtual positioning of the implant to the design of a customized drill guide. (orig.)

  15. Preparation of targets by ion implantation

    Santry, D.C.

    1976-01-01

    Various factors are described which are involved in target preparation by direct ion implantation and the limitations and pitfalls of the method are emphasized. Examples are given of experiments for which ion implanted targets are well suited. (author)

  16. Surgical Templates for Dental Implant Positioning; Current ...

    prosthodontics; however, designing an implant‑supported prosthesis with function .... template where a provisional fixed restoration bridges the implant site. Pesun and ... in single implant therapy or short‑span implant‑supported prostheses.

  17. Implants in free fibula flap supporting dental rehabilitation - Implant and peri-implant related outcomes of a randomized clinical trial.

    Kumar, Vinay V; Ebenezer, Supriya; Kämmerer, Peer W; Jacob, P C; Kuriakose, Moni A; Hedne, Naveen; Wagner, Wilfried; Al-Nawas, Bilal

    2016-11-01

    The objective of this study was to assess the difference in success rates of implants when using two or four implant-supported-overdentures following segmental mandibular reconstruction with fibula free flap. This prospective, parallel designed, randomized clinical study was conducted with 1:1 ratio. At baseline, all participants already had segmental reconstruction of mandible with free fibula flap. The participants were randomized into two groups: Group-I received implant-supported-overdentures on two tissue-level implants and Group-II received implant-supported-overdentures on four tissue-level implants. Success rates of the implants were evaluated at 3 months, 6 months and 12 months following implant loading using marginal bone level changes as well as peri-implant indices (Buser et al., 1990). 52 patients were randomized into two treatment groups (26 each), out of which 18 patients (36 implants) of Group-I and 17 patients (68 implants) of Group-II were evaluated. One implant in Group-I was lost due to infective complications and one patient in the same group had superior barrel necrosis. There was a statistically significant increase at both time points (p = 0.03, p = 0.04 at 6 months, 12 months) in the amount of marginal bone loss in Group-I (0.4 mm, 0.5 mm at 6 months, 12 months) as compared to Group-II (0.1 mm, 0.2 mm at 6 months, 12 months). There were no clinically significant changes peri-implant parameters between both groups. Peri-implant soft tissue hyperplasia was seen in both groups, 32% of implants at 3-months, 26% at 6-months and 3% at 12-months follow-up. The results of this study show that patients with 2-implant-supported-overdentures had higher marginal bone loss as compared to patients with 4-implant-supported-overdentures. There were no clinically significant differences in peri-implant soft tissue factors in patients with 2- or 4-implant-supported-overdentures. Hyperplastic peri-implant tissues are common in the early implant

  18. Implant surface preparation in the surgical treatment of experimental peri-implantitis with autogenous bone graft and ePTFE membrane in cynomolgus monkeys

    Schou, Søren; Holmstrup, Palle; Jørgensen, Torben

    2003-01-01

    peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology......peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology...

  19. Impact of cone-beam computed tomography on implant planning and on prediction of implant size

    Pedroso, Ludmila Assuncao de Mello; Silva, Maria Alves Garcia Santos, E-mail: ludmilapedroso@hotmail.com [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Fac. de Odontologia; Garcia, Robson Rodrigues [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Fac. de Odontologia. Dept. de Medicina Oral; Leles, Jose Luiz Rodrigues [Universidade Paulista (UNIP), Goiania, GO (Brazil). Fac. de Odontologia. Dept. de Cirurgia; Leles, Claudio Rodrigues [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Fac. de Odontologia. Dept. de Prevencao e Reabilitacao Oral

    2013-11-15

    The aim was to investigate the impact of cone-beam computed tomography (CBCT) on implant planning and on prediction of final implant size. Consecutive patients referred for implant treatment were submitted to clinical examination, panoramic (PAN) radiography and a CBCT exam. Initial planning of implant length and width was assessed based on clinical and PAN exams, and final planning, on CBCT exam to complement diagnosis. The actual dimensions of the implants placed during surgery were compared with those obtained during initial and final planning, using the McNemmar test (p < 0.05). The final sample comprised 95 implants in 27 patients, distributed over the maxilla and mandible. Agreement in implant length was 50.5% between initial and final planning, and correct prediction of the actual implant length was 40.0% and 69.5%, using PAN and CBCT exams, respectively. Agreement in implant width assessment ranged from 69.5% to 73.7%. A paired comparison of the frequency of changes between initial or final planning and implant placement (McNemmar test) showed greater frequency of changes in initial planning for implant length (p < 0.001), but not for implant width (p = 0.850). The frequency of changes was not influenced by implant location at any stage of implant planning (chi-square test, p > 0.05). It was concluded that CBCT improves the ability of predicting the actual implant length and reduces inaccuracy in surgical dental implant planning. (author)

  20. Implantable Cardiac Pacemakers – 50 Years from the First Implantation

    Ratko Magjarević

    2010-01-01

    Overview: Development of implantable cardiac pacemaker was enabled by another important invention, the silicon transistor. h ough the invention of suitable lithium cells as appropriate power supply was essential for prolongation of battery life cycle and for increased reliability of pacemakers, main milestones in the development were associated with technological breakthroughs in electronics: from transistors, which introduced such features as small size and low power consumption, to hybrid and integrated circuits, which enabled programmability, microprocessors, which added more options in programming (multiprogrammability, diagnostics and telemetry, and the ICT (information communication technology that enabled physicians remote access to patients and interrogation of their implantable devices. Conclusions: Implantable pacemakers are reliable devices indicated for a wide range of dif erent therapies of cardiac rhythm disorders and heart failure. h ere is still a lot to learn about the physiology of a normal heart and even more about the failing heart. Modern pacemakers provide physicians valuable information from pacemakers’ memory via the built-in telemetry system. h ese information help physicians to better understand pathologic processes within the heart, thus contributing to the development of new ideas for treatment of diseases and for precise tailoring of the therapy to the patient’s needs. Although implantable pacemakers have reached the level of mature technology, they will continue to develop with therapies and diagnostics to facilitate a higher quality of life.

  1. Augmentation Mammaplasty Using Implants: A Review

    Susumu Takayanagi

    2012-09-01

    Full Text Available One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed.

  2. Augmentation Mammaplasty Using Implants: A Review

    Susumu Takayanagi

    2012-09-01

    Full Text Available One of the techniques for augmentation mammaplasty is the procedure using implants. Eventhough this technique has been used for many years, there are still several controversial issuesto be discussed and overcome for patient safety. In this review article, capsular contracture,leak or rupture of the implants, possible systemic disease, relation with breast cancer, andrecent problems with Poly Implant Prothese implants are described and discussed.

  3. Plasma immersion ion implantation into insulating materials

    Tian Xiubo; Yang Shiqin

    2006-01-01

    Plasma immersion ion implantation (PIII) is an effective surface modification tool. During PIII processes, the objects to be treated are immersed in plasmas and then biased to negative potential. Consequently the plasma sheath forms and ion implantation may be performed. The pre-requirement of plasma implantation is that the object is conductive. So it seems difficult to treat the insulating materials. The paper focuses on the possibilities of plasma implantation into insulting materials and presents some examples. (authors)

  4. Influence of different implant materials on the primary stability of orthodontic mini-implants

    Chin-Yun Pan; Szu-Ting Chou; Yu-Chuan Tseng; Yi-Hsin Yang; Chao-Yi Wu; Ting-Hsun Lan; Pao-Hsin Liu; Hong-Po Chang

    2012-01-01

    This study evaluates the influence of different implant materials on the primary stability of orthodontic mini-implants by measuring the resonance frequency. Twenty-five orthodontic mini-implants with a diameter of 2 mm were used. The first group contained stainless steel mini-implants with two different lengths (10 and 12 mm). The second group included titanium alloy mini-implants with two different lengths (10 and 12 mm) and stainless steel mini-implants 10 mm in length. The mini-implants w...

  5. Scalloped Implant-Abutment Connection Compared to Conventional Flat Implant-Abutment Connection

    Starch-Jensen, Thomas; Christensen, Ann-Eva; Lorenzen, Henning

    2017-01-01

    OBJECTIVES: The objective was to test the hypothesis of no difference in implant treatment outcome after installation of implants with a scalloped implant-abutment connection compared to a flat implant-abutment connection. MATERIAL AND METHODS: A MEDLINE (PubMed), Embase and Cochrane library search......-abutment connection. There were no significant differences between the two treatment modalities regarding professional or patient-reported outcome measures. Meta-analysis disclosed a mean difference of peri-implant marginal bone loss of 1.56 mm (confidence interval: 0.87 to 2.25), indicating significant more bone...... loss around implants with a scalloped implant-abutment connection. CONCLUSIONS: A scalloped implant-abutment connection seems to be associated with higher peri-implant marginal bone loss compared to a flat implant-abutment connection. Therefore, the hypothesis of the present systematic review must...

  6. [The elementary discussion on digital implant dentistry].

    Su, Y C

    2016-04-09

    It is a digital age today. Exposed to all kinds of digital products in many fields. Certainly, implant dentistry is not exception. Digitalization could improve the outcomes and could decrease the complications of implant dentistry. This paper introduces the concepts, definitions, advantages, disadvantages, limitations and errors of digital implant dentistry.

  7. Active implants and scaffolds for tissue regeneration

    Zilberman, Meital

    2011-01-01

    Active implants are actually drug or protein-eluting implants that induce healing effects, in addition to their regular task, such as support. This book gives a broad overview of biomaterial platforms used as basic elements of drug-eluting implants.

  8. Surgical Templates for Dental Implant Positioning; Current ...

    Since the mid‑20th century, there has been an increase in interest in the implant process for the replacement of missing teeth. Branemark ... Ideal placement of the implant facilitates the establishment of favorable forces on the implants and the prosthetic component as well as ensures an aesthetic outcome. Therefore, it is ...

  9. The endometrial factor in human embryo implantation

    Boomsma, C.M.

    2009-01-01

    The studies presented in this thesis aimed to explore the role of the endometrium in the implantation process. At present, embryo implantation is the major rate-limiting step for success in fertility treatment. Clinicians have sought to develop clinical interventions aimed at enhancing implantation

  10. Macro design morphology of endosseous dental implants.

    Sahiwal, Indira G; Woody, Ronald D; Benson, Byron W; Guillen, Guillermo E

    2002-05-01

    The identification of dental implant bodies in patients without available records is a considerable problem due to increased patient mobility and to the large number of implant systems with different designs. The purpose of this study was to document the designs of selected implants to help clinicians identify these implants from their radiographic images. More than 50 implant manufacturers were contacted and asked to provide implants with dimensions as close as possible to 3.75 mm (diameter) x 10 mm (length). Forty-four implants were donated, separated into threaded and non-threaded categories, and further sorted into tapered and non-tapered categories. The implants were examined visually, and features on the entire circumference and length of each implant were recorded and categorized as coronal, midbody, or apical. A series of tables describe the 44 implants according to coronal, midbody, and apical features. The results of this project offer dentists basic knowledge of the design of selected dental implants. Such knowledge can aid the radiographic identification of these implants.

  11. Ten-year in vivo wear measurement of a fully congruent mobile bearing unicompartmental knee arthroplasty.

    Price, A J; Short, A; Kellett, C; Beard, D; Gill, H; Pandit, H; Dodd, C A F; Murray, D W

    2005-11-01

    Polyethylene particulate wear debris continues to be implicated in the aetiology of aseptic loosening following knee arthroplasty. The Oxford unicompartmental knee arthroplasty employs a spherical femoral component and a fully congruous meniscal bearing to increase contact area and theoretically reduce the potential for polyethylene wear. This study measures the in vivo ten-year linear wear of the device, using a roentgenstereophotogrammetric technique. In this in vivo study, seven medial Oxford unicompartmental prostheses, which had been implanted ten years previously were studied. Stereo pairs of radiographs were acquired for each patient and the films were analysed using a roentgen stereophotogrammetric analysis calibration and a computer-aided design model silhouette-fitting technique. Penetration of the femoral component into the original volume of the bearing was our estimate of linear wear. In addition, eight control patients were examined less than three weeks post-insertion of an Oxford prosthesis, where no wear would be expected. The control group showed no measured wear and suggested a system accuracy of 0.1 mm. At ten years, the mean linear wear rate was 0.02 mm/year. The results from this in vivo study confirm that the device has low ten-year linear wear in clinical practice. This may offer the device a survival advantage in the long term.

  12. Annealing behaviour of MeV erbium implanted lithium niobate

    Gortmaker, P; McCallum, J C [Royal Melbourne Inst. of Tech., VIC (Australia)

    1994-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  13. Annealing behaviour of MeV erbium implanted lithium niobate

    Gortmaker, P.; McCallum, J.C. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  14. Implantable batteryless device for on-demand and pulsatile insulin administration

    Lee, Seung Ho; Lee, Young Bin; Kim, Byung Hwi; Lee, Cheol; Cho, Young Min; Kim, Se-Na; Park, Chun Gwon; Cho, Yong-Chan; Choy, Young Bin

    2017-04-01

    Many implantable systems have been designed for long-term, pulsatile delivery of insulin, but the lifetime of these devices is limited by the need for battery replacement and consequent replacement surgery. Here we propose a batteryless, fully implantable insulin pump that can be actuated by a magnetic field. The pump is prepared by simple-assembly of magnets and constituent units and comprises a drug reservoir and actuator equipped with a plunger and barrel, each assembled with a magnet. The plunger moves to noninvasively infuse insulin only when a magnetic field is applied on the exterior surface of the body. Here we show that the dose is easily controlled by varying the number of magnet applications. Also, pump implantation in diabetic rats results in profiles of insulin concentration and decreased blood glucose levels similar to those observed in rats treated with conventional subcutaneous insulin injections.

  15. Ion implantation of Cd and Ag into AlN and GaN

    Miranda, Sérgio M C; Correia, João Guilherme; Vianden, Reiner; Johnston, Karl; Alves, Eduardo; Lorenz, Katharina

    2012-01-01

    GaN and AlN thin films were implanted with cadmium (Cd) or silver (Ag), to fluences ranging from 1×1013 to 1.7 × 1015 at/cm$^{2}$. The implanted samples were annealed at 950 ºC under flowing nitrogen. While implantation damage could be fully removed for the lowest fluences, for higher fluences the crystal quality was only partially recovered. For the high fluence samples the lattice site location of the ions was studied by Rutherford Backscattering/ channelling (RBS/C). Cd ions are found to be incorporated in substitutional cation sites (Al or Ga) while Ag is slightly displaced from this position. To further investigate the incorporation sites, Perturbed Angular Correlation (PAC) measurements were performed and the electric field gradients at the site of the probe nuclei were determined.

  16. Digital Workflow for Computer-Guided Implant Surgery in Edentulous Patients: A Case Report.

    Oh, Ji-Hyeon; An, Xueyin; Jeong, Seung-Mi; Choi, Byung-Ho

    2017-12-01

    The purpose of this article was to describe a fully digital workflow used to perform computer-guided flapless implant placement in an edentulous patient without the use of conventional impressions, models, or a radiographic guide. Digital data for the workflow were acquired using an intraoral scanner and cone-beam computed tomography (CBCT). The image fusion of the intraoral scan data and CBCT data was performed by matching resin markers placed in the patient's mouth. The definitive digital data were used to design a prosthetically driven implant position, surgical template, and computer-aided design and computer-aided manufacturing fabricated fixed dental prosthesis. The authors believe this is the first published case describing such a technique in computer-guided flapless implant surgery for edentulous patients. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  17. Current State and Future Perspectives of Energy Sources for Totally Implantable Cardiac Devices.

    Bleszynski, Peter A; Luc, Jessica G Y; Schade, Peter; PhilLips, Steven J; Tchantchaleishvili, Vakhtang

    There is a large population of patients with end-stage congestive heart failure who cannot be treated by means of conventional cardiac surgery, cardiac transplantation, or chronic catecholamine infusions. Implantable cardiac devices, many designated as destination therapy, have revolutionized patient care and outcomes, although infection and complications related to external power sources or routine battery exchange remain a substantial risk. Complications from repeat battery replacement, power failure, and infections ultimately endanger the original objectives of implantable biomedical device therapy - eliminating the intended patient autonomy, affecting patient quality of life and survival. We sought to review the limitations of current cardiac biomedical device energy sources and discuss the current state and trends of future potential energy sources in pursuit of a lifelong fully implantable biomedical device.

  18. Imaging of common breast implants and implant-related complications: A pictorial essay

    Shah, Amisha T; Jankharia, Bijal B

    2016-01-01

    The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance i...

  19. Clinical Application of Fully Covered Self-Expandable Metal Stents in the Treatment of Bronchial Fistula.

    Cao, Ming; Zhu, Qiang; Wang, Wei; Zhang, Tian Xiao; Jiang, Min Zhong; Zang, Qi

    2016-09-01

    Background The study was designed to access the feasibility, safety, and efficacy of fully covered self-expandable metal stents in the treatment of bronchial fistula. Methods Clinical data of nine patients (seven males and two females) who were treated with placement of tracheobronchial or bronchial fully covered self-expandable metal stents from August 2005 to November 2011 were analyzed retrospectively. Among these patients, seven were diagnosed with bronchopleural fistula, one with tracheopleural fistula, and one with left main bronchoesophageal fistula. Eight had accompanying thoracic empyema. The fistula orifices ranged from 3.5 mm to 25 mm in diameter. All patients received topical anesthesia. L-shaped stents were placed in six patients and I-shaped stents in three under fluoroscopic guidance. After stent placement, patients with empyema were treated with pleural lavage. Results Stent placement in the tracheobronchial tree was successful in all patients, without procedure-related complications. The operating time was 5 to 16 minutes. A small amount of bubble overflowed from the intrathoracic drainage tube of only one patient. In the other patients, the bubble in the intrathoracic drainage tube disappeared immediately or angiography showed no overflow of contrast agent from the fistula orifice. The effective rate of fistula orifice closure after stent placement was 100%, with 88.9% rated as excellent. One patient coughed the stent out 5 days after placement and hence a new stent was placed. Among the patients with empyema, one died of septicemia arising from empyema on day 8 and another died of brain metastases of lung cancer 6 months after stent insertion with persistent empyema. In the other six patients, empyema resolved after 2 to 5 months (cure rate 75%). Seven patients were followed up for 3 to 36 months. During follow-up, one stent was removed 8 months after implantation due to difficult expectoration, without recurrent empyema. The remaining

  20. [Clinical application of a fully covered self-expandable metallic stent in treatment of airway fistula].

    Zhu, Qiang; Zang, Qi; Jiang, Zhong-min; Wang, Wei; Cao, Ming

    2013-06-01

    To assess the feasibility, safety and efficacy of the use of a fully covered self-expandable stent for the treatment of airway fistula. From August 2005 to November 2011, 9 patients underwent treatment by the introduction of a tracheo-bronchial or bronchial fully covered self-expandable metallic stent. There were 7 males and 2 females, aged from 28-65 years with a mean of 46 years. In this group, 7 cases were diagnosed as bronchopleural fistula, 1 case as tracheopleural fistula, 1 case as broncho-esophageal fistula, 8 cases with thoracic empyema. The fistula orifices were from 3.5-25.0 mm in diameter with a mean 8.4 mm. All patients received topical anesthesia, and L-shaped stent was placed in 6 patients and I-shaped stent in 3 patients under fluoroscopic guidance. After the stent placement, the patients with empyema were treated with continual irrigation of the empyema cavity. Stent placement in the tracheo-bronchial tree was technically successful in all patients, without procedure-related complications. The operating time was from 5-16 minutes, mean time (10 ± 4) minutes. Except for 1 patient, immediate closure of the airway fistula was achieved in the other patients after the procedure, as shown by the immediate cessation of bubbling in the chest drain system or the contrast examination. In this study, 1 patient coughed the inserted stent out due to irritable cough on the 5th day and had to receive repositioning of a new stent. Among the patients who were with empyema, 1 patient died of septicemia on the 8th day and 1 patient died of brain metastases from lung cancer 6 months after the stent insertion with empyema not cured, the other 6 patients' empyema healed from 2-5 months, mean time 3.7 months. Seven patients were followed from 3 to 36 months with a median of 13.5 months. During follow-up, 1 stent was removed from a patient 8 months after the stent implantation without empyema recurred. The remaining patient presented good tolerability to the existence of

  1. Clinical outcome of narrow-diameter (3.3-mm) locking-taper implants: a prospective study with 1 to 10 years of follow-up.

    Mangano, Francesco; Shibli, Jamil A; Sammons, Rachel L; Veronesi, Giovanni; Piattelli, Adriano; Mangano, Carlo

    2014-01-01

    To evaluate the outcome of narrow-diameter (3.3-mm) locking-taper implants used in the rehabilitation of partially and fully edentulous patients over a 10-year period. Between January 2002 and December 2011, all patients referred to a private dental clinic for treatment with narrow-diameter implants were enrolled in this study. At each annual follow-up session, clinical and radiographic parameters were assessed; the outcome measurements were implant failure, peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact [DIB]), and biologic and technical complications. The cumulative survival rate (CSR) was assessed using the Kaplan-Meier survival estimator; Tarone-Ware and chi-square analyses were used to evaluate correlations between the study variables. The statistical analysis was performed at the patient- and implant-level. A total of 324 narrow-diameter implants were placed in 279 patients (159 men, 120 women; age: 25 to 73 years). Four implants failed, for an overall CSR of 98.5% (patient-based) and 98.7% (implant-based) at the 10-year follow-up. The survival rate did not differ significantly with respect to patients' sex, age, smoking or parafunctional habits, bone type, prosthetic restoration, or implant location, position, or length. Among the surviving implants, a mean DIB of 0.31 ± 0.23 mm, 0.45 ± 0.27 mm, and 0.69 ± 0.28 mm was observed at the 1-, 5-, and 10-year follow-up examinations, respectively. A few biologic (1.2%) and technical complications (7.5%) were reported. Within the limitations of this study, it can be concluded that narrow-diameter locking-taper implants represent a good treatment option for the prosthetic rehabilitation of partially and totally edentulous patients.

  2. Cochlear implant after bacterial meningitis.

    Bille, Jesper; Ovesen, Therese

    2014-06-01

    The aim of this retrospective case study at a tertiary referral center was to investigate the outcome of cochlear implantation (CI) in children with sensorineural hearing loss due to meningitis compared to CI in children with deafness due to other reasons. This post-meningial group (PMG) consisted of 22 children undergoing CI due to deafness induced by meningitis, between December 1996 and January 2012. Five children had bilateral simultaneous implantation. None was excluded and the children were followed for at least 3 years. Operations were carried out by one of two surgeons using similar techniques in all cases. Each patient from the PMG was matched 2:1 with children having implantation for other reasons according to age and follow up (control group). Overall, the median category of auditory performance (CAP) and speech intelligibility rating (SIR) score were not statistically significantly different between the two groups. The presence of additional central nervous system (CNS) disorders (post-meningeal sequelae), however, correlated significantly with poorer outcome CI was a safe procedure without surgical complications in the present study. It is possible to restore auditory capacity and speech performance to a degree comparable to children undergoing implantation for other reasons. A statistically important variable is secondary CNS involvement. The rehabilitation program after CI should be adjusted according to these additional handicaps. It is recommended to screen meningitis patients as fast as possible to identify those with hearing loss and initiate treatment with hearing aids or CI. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

  3. Annealing of ion implanted silicon

    Chivers, D.; Smith, B.J.; Stephen, J.; Fisher, M.

    1980-09-01

    The newer uses of ion implantation require a higher dose rate. This has led to the introduction of high beam current implanters; the wafers move in front of a stationary beam to give a scanning effect. This can lead to non-uniform heating of the wafer. Variations in the sheet resistance of the layers can be very non-uniform following thermal annealing. Non-uniformity in the effective doping both over a single wafer and from one wafer to another, can affect the usefulness of ion implantation in high dose rate applications. Experiments to determine the extent of non-uniformity in sheet resistance, and to see if it is correlated to the annealing scheme have been carried out. Details of the implantation parameters are given. It was found that best results were obtained when layers were annealed at the maximum possible temperature. For arsenic, phosphorus and antimony layers, improvements were observed up to 1200 0 C and boron up to 950 0 C. Usually, it is best to heat the layer directly to the maximum temperature to produce the most uniform layer; with phosphorus layers however it is better to pre-heat to 1050 0 C. (U.K.)

  4. Implantation of boron in silicon

    Hofker, W.K.

    1975-01-01

    The distribution versus depth of boron implanted in silicon and the corresponding electrical activity obtained after annealing are studied. The boron distributions are measured by secondary-ion mass spectrometry. Boron distributions implanted at energies in the range from 30 keV to 800 keV in amorphous and polycrystalline silicon are analysed. Moments of these distributions are determined by a curve-fitting programme and compared with moments calculated by Winterbon. Boron distributions obtained by implantations along a dense crystallographic direction in monocrystalline silicon are found to have penetrating tails. After investigation of some possible mechanisms of tail formation it is concluded that the tails are due to channelling. It was found that the behaviour of boron during annealing is determined by the properties of three boron fractions consisting of precipitated boron, interstitial boron and substitutional boron. The electrical activity of the boron versus depth is found to be consistent with the three boron fractions. A peculiar redistribution of boron is found which is induced by the implantation of a high dose of heavy ions and subsequent annealing. Different mechanisms which may cause the observed effects, such as thermal diffusion which is influenced by lattice strain and damage, are discussed. (Auth.)

  5. [Dental implant restoration abutment selection].

    Bin, Shi; Hao, Zeng

    2017-04-01

    An increasing number of implant restoration abutment types are produced with the rapid development of dental implantology. Although various abutments can meet different clinical demands, the selection of the appropriate abutment is both difficult and confusing. This article aims to help clinicians select the appropriate abutment by describing abutment design, types, and selection criteria.

  6. Reading skills after cochlear implantation

    Vermeulen, A.M.

    2007-01-01

    It has frequently been found that profoundly deaf children with conventional hearing aids have difficulties with the comprehension of written text. Cochlear Implants (CIs) were expected to enhance the reading comprehension of these profoundly deaf children because they provide auditory access to

  7. Advancing Binaural Cochlear Implant Technology

    Mathias Dietz

    2015-12-01

    Full Text Available This special issue contains a collection of 13 papers highlighting the collaborative research and engineering project entitled Advancing Binaural Cochlear Implant Technology—ABCIT—as well as research spin-offs from the project. In this introductory editorial, a brief history of the project is provided, alongside an overview of the studies.

  8. Cochlear implant: the family's perspective.

    Vieira, Sheila de Souza; Dupas, Giselle; Chiari, Brasilia Maria

    2018-07-01

    To understand the family's experience of a child who uses a cochlear implant (CI). Specifically, to identify the difficulties, changes, and feelings entailed by deafness and the use of the CI; the coping strategies; and to understand the role of the family for the child with a CI. Qualitative research, using Symbolic Interactionism and Straussian Grounded Theory as the theoretical and methodological frameworks, respectively. Data collection instrument: semi-structured interview. A total of 9 families (32 individuals) participated in the study. The children's ages ranged from 6 to 11 years old (mean = 8.9 years old). Their experience is described in the following categories: Having to fight for results, Coping with difficult situations, Recognizing that you are not alone, Learning to overcome, and Having one's life restored by the implant. Cochlear implantation changes the direction of the child and the family's life by restoring the child's opportunity to hear and to obtain good results in her personal, social, and academic development. Even after implantation, the child continues to experience difficulties and requires the family's mobilization in order to be successful. The family is the principal actor in the process of the child's rehabilitation.

  9. Effect of Intraoperative Three-Dimensional Imaging During the Reduction and Fixation of Displaced Calcaneal Fractures on Articular Congruence and Implant Fixation

    Eckardt, Henrik; Lind, Marianne

    2015-01-01

    BACKGROUND: Operative treatment of displaced calcaneal fractures should restore joint congruence, but conventional fluoroscopy is unable to fully visualize the subtalar joint. We questioned whether intraoperative 3-dimensional (3D) imaging would aid in the reduction of calcaneal fractures......, resulting in improved articular congruence and implant positioning. METHOD: Sixty-two displaced calcaneal fractures were operated on using standard fluoroscopic views. When the surgeon had achieved a satisfactory reduction, an intraoperative 3D scan was conducted, malreductions or implant imperfections were...

  10. Usher syndrome and cochlear implantation.

    Loundon, Natalie; Marlin, Sandrine; Busquet, Denise; Denoyelle, Françoise; Roger, Gilles; Renaud, Francis; Garabedian, Erea Noel

    2003-03-01

    To evaluate the symptoms leading to diagnosis and the quality of rehabilitation after cochlear implantation in Usher syndrome. Retrospective cohort study. ENT department of a tertiary referral hospital. Among 210 patients given an implantation in the Ear, Nose, and Throat department, 185 were congenitally deaf and 13 had Usher syndrome (7.0%). Five had a family history of Usher, and eight were sporadic cases. Eleven cases were Usher type I, one was Usher type III, and one was not classified. The age at implantation ranged from 18 months to 44 years (mean, 6 years 1 month). The mean follow-up was 52 months (range, 9 months to 9 years). All patients had audiophonological and clinical examination, computed tomography scan of the temporal bones, ophthalmologic examination with fundoscopy, and an electroretinogram. Cerebral magnetic resonance imaging and vestibular examination were performed in 9 of 13 and 10 of 13 cases, respectively. Logopedic outcome measured preimplant and postimplant closed- and open-set word recognition and oral expression at follow-up. The most frequent initial sign of Usher syndrome was delayed walking, with a mean age of 20 months. Among the 172 other congenitally deaf children with implants, when deafness was not associated with other neurologic disorders, the mean age at walking was 14 months (p < 0.001). The fundoscopy was always abnormal after the age of 5 years, and the electroretinogram was abnormal in all cases. Vestibular function was abnormal in all but one case (nonclassified). The computed tomography scan and the magnetic resonance imaging were always normal. Logopedic results with cochlear implants showed good perception skills in all but one case. The best perceptive results were obtained in children implanted before the age of 9 years. Oral language had significantly progressed in 9 of 13 at follow-up. There was no relation between the visual acuity and the logopedic results. The earliest clinical sign associated with deafness

  11. Failure analysis of fractured dental zirconia implants.

    Gahlert, M; Burtscher, D; Grunert, I; Kniha, H; Steinhauser, E

    2012-03-01

    The purpose of the present study was the macroscopic and microscopic failure analysis of fractured zirconia dental implants. Thirteen fractured one-piece zirconia implants (Z-Look3) out of 170 inserted implants with an average in situ period of 36.75±5.34 months (range from 20 to 56 months, median 38 months) were prepared for macroscopic and microscopic (scanning electron microscopy [SEM]) failure analysis. These 170 implants were inserted in 79 patients. The patient histories were compared with fracture incidences to identify the reasons for the failure of the implants. Twelve of these fractured implants had a diameter of 3.25 mm and one implant had a diameter of 4 mm. All fractured implants were located in the anterior side of the maxilla and mandibula. The patient with the fracture of the 4 mm diameter implant was adversely affected by strong bruxism. By failure analysis (SEM), it could be demonstrated that in all cases, mechanical overloading caused the fracture of the implants. Inhomogeneities and internal defects of the ceramic material could be excluded, but notches and scratches due to sandblasting of the surface led to local stress concentrations that led to the mentioned mechanical overloading by bending loads. The present study identified a fracture rate of nearly 10% within a follow-up period of 36.75 months after prosthetic loading. Ninety-two per cent of the fractured implants were so-called diameter reduced implants (diameter 3.25 mm). These diameter reduced implants cannot be recommended for further clinical use. Improvement of the ceramic material and modification of the implant geometry has to be carried out to reduce the failure rate of small-sized ceramic implants. Nevertheless, due to the lack of appropriate laboratory testing, only clinical studies will demonstrate clearly whether and how far the failure rate can be reduced. © 2011 John Wiley & Sons A/S.

  12. Effectiveness of Implant Therapy Analyzed in a Swedish Population: Prevalence of Peri-implantitis.

    Derks, J; Schaller, D; Håkansson, J; Wennström, J L; Tomasi, C; Berglundh, T

    2016-01-01

    Peri-implantitis is an inflammatory disease affecting soft and hard tissues surrounding dental implants. As the global number of individuals that undergo restorative therapy through dental implants increases, peri-implantitis is considered as a major and growing problem in dentistry. A randomly selected sample of 588 patients who all had received implant-supported therapy 9 y earlier was clinically and radiographically examined. Prevalence of peri-implantitis was assessed and risk indicators were identified by multilevel regression analysis. Forty-five percent of all patients presented with peri-implantitis (bleeding on probing/suppuration and bone loss >0.5 mm). Moderate/severe peri-implantitis (bleeding on probing/suppuration and bone loss >2 mm) was diagnosed in 14.5%. Patients with periodontitis and with ≥4 implants, as well as implants of certain brands and prosthetic therapy delivered by general practitioners, exhibited higher odds ratios for moderate/severe peri-implantitis. Similarly, higher odds ratios were identified for implants installed in the mandible and with crown restoration margins positioned ≤1.5 mm from the crestal bone at baseline. It is suggested that peri-implantitis is a common condition and that several patient- and implant-related factors influence the risk for moderate/severe peri-implantitis (ClinicalTrials.gov NCT01825772). © International & American Associations for Dental Research 2015.

  13. Asteroseismology of pulsating DA white dwarfs with fully evolutionary models

    Althaus L.G.

    2013-03-01

    Full Text Available We present a new approach for asteroseismology of DA white dwarfs that consists in the employment of a large set of non-static, physically sound, fully evolutionary models representative of these stars. We already have applied this approach with success to pulsating PG1159 stars (GW Vir variables. Our white dwarf models, which cover a wide range of stellar masses, effective temperatures, and envelope thicknesses, are the result of fully evolutionary computations that take into account the complete history of the progenitor stars from the ZAMS. In particular, the models are characterized by self-consistent chemical structures from the centre to the surface, a crucial aspect of white dwarf asteroseismology. We apply this approach to an ensemble of 44 bright DAV (ZZ Ceti stars.

  14. Toward textbook multigrid efficiency for fully implicit resistive magnetohydrodynamics

    Adams, Mark F.; Samtaney, Ravi; Brandt, Achi

    2013-01-01

    Multigrid methods can solve some classes of elliptic and parabolic equations to accuracy below the truncation error with a work-cost equivalent to a few residual calculations so-called textbook multigrid efficiency. We investigate methods to solve the system of equations that arise in time dependent magnetohydrodynamics (MHD) simulations with textbook multigrid efficiency. We apply multigrid techniques such as geometric interpolation, full approximate storage, Gauss-Seidel smoothers, and defect correction for fully implicit, nonlinear, second-order finite volume discretizations of MHD. We apply these methods to a standard resistive MHD benchmark problem, the GEM reconnection problem, and add a strong magnetic guide field, which is a critical characteristic of magnetically confined fusion plasmas. We show that our multigrid methods can achieve near textbook efficiency on fully implicit resistive MHD simulations.

  15. Solution of the fully fuzzy linear systems using iterative techniques

    Dehghan, Mehdi; Hashemi, Behnam; Ghatee, Mehdi

    2007-01-01

    This paper mainly intends to discuss the iterative solution of fully fuzzy linear systems which we call FFLS. We employ Dubois and Prade's approximate arithmetic operators on LR fuzzy numbers for finding a positive fuzzy vector x-tilde which satisfies A-tildex-tilde=b, where A-tilde and b-tilde are a fuzzy matrix and a fuzzy vector, respectively. Please note that the positivity assumption is not so restrictive in applied problems. We transform FFLS and propose iterative techniques such as Richardson, Jacobi, Jacobi overrelaxation (JOR), Gauss-Seidel, successive overrelaxation (SOR), accelerated overrelaxation (AOR), symmetric and unsymmetric SOR (SSOR and USSOR) and extrapolated modified Aitken (EMA) for solving FFLS. In addition, the methods of Newton, quasi-Newton and conjugate gradient are proposed from nonlinear programming for solving a fully fuzzy linear system. Various numerical examples are also given to show the efficiency of the proposed schemes

  16. Toward textbook multigrid efficiency for fully implicit resistive magnetohydrodynamics

    Adams, Mark F.; Samtaney, Ravi; Brandt, Achi

    2010-01-01

    Multigrid methods can solve some classes of elliptic and parabolic equations to accuracy below the truncation error with a work-cost equivalent to a few residual calculations so-called "textbook" multigrid efficiency. We investigate methods to solve the system of equations that arise in time dependent magnetohydrodynamics (MHD) simulations with textbook multigrid efficiency. We apply multigrid techniques such as geometric interpolation, full approximate storage, Gauss-Seidel smoothers, and defect correction for fully implicit, nonlinear, second-order finite volume discretizations of MHD. We apply these methods to a standard resistive MHD benchmark problem, the GEM reconnection problem, and add a strong magnetic guide field, which is a critical characteristic of magnetically confined fusion plasmas. We show that our multigrid methods can achieve near textbook efficiency on fully implicit resistive MHD simulations. (C) 2010 Elsevier Inc. All rights reserved.

  17. Trial production and characterisation of fully calcia-stabilised zirconia

    George, A.M.; Karkhanavala, M.D.

    1980-01-01

    A process for manufacture of stabilized zirconia powder has been developed. The process is quite versatile since stabilization is achieved at relatively low temperatures (950deg - 1000deg C) and can be used for manufacture of either fully or partially calcia-stabilized zirconia. A 100 Kg trial batch of fully stabilized zirconia powder was produced accordingly at the Indian Rare Earths Ltd. plant and its characteristics were evaluated by XRD, microscopy, surface area and density measurements. The powder on firing at 1400deg C showed considerable volume shrinkage, as expected. On manually compacting with a phosphatic binder and firing for 8-10 hrs at 1300deg-1400deg C sintered shapes having bulk densities around 80-85% T.D. are easily obtained. Details of the measurements and the prospective industrial applications of the material are discussed. (auth.)

  18. Toward textbook multigrid efficiency for fully implicit resistive magnetohydrodynamics

    Adams, Mark F.

    2010-09-01

    Multigrid methods can solve some classes of elliptic and parabolic equations to accuracy below the truncation error with a work-cost equivalent to a few residual calculations so-called "textbook" multigrid efficiency. We investigate methods to solve the system of equations that arise in time dependent magnetohydrodynamics (MHD) simulations with textbook multigrid efficiency. We apply multigrid techniques such as geometric interpolation, full approximate storage, Gauss-Seidel smoothers, and defect correction for fully implicit, nonlinear, second-order finite volume discretizations of MHD. We apply these methods to a standard resistive MHD benchmark problem, the GEM reconnection problem, and add a strong magnetic guide field, which is a critical characteristic of magnetically confined fusion plasmas. We show that our multigrid methods can achieve near textbook efficiency on fully implicit resistive MHD simulations. (C) 2010 Elsevier Inc. All rights reserved.

  19. A Fully Symmetric and Completely Decoupled MEMS-SOI Gyroscope

    Abdelhameed SHARAF

    2011-04-01

    Full Text Available This paper introduces a novel MEMS gyroscope that is capable of exciting the drive mode differentially. The structure also decouples the drive and sense modes via an intermediate mass and decoupling beams. Both drive and sense modes are fully differential enabling control over the zero-rate-output for the former and maximizing output sensitivity using a bridge circuit for the latter. Further, the structure is fully symmetric about the x- and y- axes which results in minimizing the temperature sensitivity problem. Complete analytical analysis based on the equations of motion was performed and verified using two commercially available finite element software packages. Results from both methods are in good agreement. The analysis of the sensor shows an electrical sensitivity of 1.14 (mV/(º/s. The gyroscope was fabricated using single mask and deep reactive ion etching. The measurement of the resonance frequency performed showing a good agreement with the analytical and numerical analysis.

  20. The production of fully deacetylated chitosan by compression method

    Xiaofei He

    2016-03-01

    Full Text Available Chitosan’s activities are significantly affected by degree of deacetylation (DDA, while fully deacetylated chitosan is difficult to produce in a large scale. Therefore, this paper introduces a compression method for preparing 100% deacetylated chitosan with less environmental pollution. The product is characterized by XRD, FT-IR, UV and HPLC. The 100% fully deacetylated chitosan is produced in low-concentration alkali and high-pressure conditions, which only requires 15% alkali solution and 1:10 chitosan powder to NaOH solution ratio under 0.11–0.12 MPa for 120 min. When the alkali concentration varied from 5% to 15%, the chitosan with ultra-high DDA value (up to 95% is produced.

  1. Toward textbook multigrid efficiency for fully implicit resistive magnetohydrodynamics

    Adams, Mark F.; Samtaney, Ravi; Brandt, Achi

    2010-01-01

    Multigrid methods can solve some classes of elliptic and parabolic equations to accuracy below the truncation error with a work-cost equivalent to a few residual calculations - so-called 'textbook' multigrid efficiency. We investigate methods to solve the system of equations that arise in time dependent magnetohydrodynamics (MHD) simulations with textbook multigrid efficiency. We apply multigrid techniques such as geometric interpolation, full approximate storage, Gauss-Seidel smoothers, and defect correction for fully implicit, nonlinear, second-order finite volume discretizations of MHD. We apply these methods to a standard resistive MHD benchmark problem, the GEM reconnection problem, and add a strong magnetic guide field, which is a critical characteristic of magnetically confined fusion plasmas. We show that our multigrid methods can achieve near textbook efficiency on fully implicit resistive MHD simulations.

  2. Configuration Synthesis for Fully Restrained 7-Cable-Driven Manipulators

    Xiaoqiang Tang

    2012-10-01

    Full Text Available Cable distribution plays a vital role in Cable Driven Parallel Manipulators (CDPMs regarding tension and workspace quality, especially in fully restrained CDPMs. This paper focuses on three typical configurations of fully restrained CDPMs with 7 cables in order to introduce an approach for configuration synthesis. Firstly, the kinematic models of three types of CDPMs with 7 cables are set up. Then, in order to evaluate workspace quality, two new indices are proposed by using tensions along each cable, which are the All Cable Tension Distribution Index (ACTDI and Global Tension Distribution Index (GTDI. Next, the three types of CDPMs with 7 cables are analysed with the two indices. At the end, according to different performance requirements, the configurations of cable distribution are discussed and selected.

  3. Externally calibrated parallel imaging for 3D multispectral imaging near metallic implants using broadband ultrashort echo time imaging.

    Wiens, Curtis N; Artz, Nathan S; Jang, Hyungseok; McMillan, Alan B; Reeder, Scott B

    2017-06-01

    To develop an externally calibrated parallel imaging technique for three-dimensional multispectral imaging (3D-MSI) in the presence of metallic implants. A fast, ultrashort echo time (UTE) calibration acquisition is proposed to enable externally calibrated parallel imaging techniques near metallic implants. The proposed calibration acquisition uses a broadband radiofrequency (RF) pulse to excite the off-resonance induced by the metallic implant, fully phase-encoded imaging to prevent in-plane distortions, and UTE to capture rapidly decaying signal. The performance of the externally calibrated parallel imaging reconstructions was assessed using phantoms and in vivo examples. Phantom and in vivo comparisons to self-calibrated parallel imaging acquisitions show that significant reductions in acquisition times can be achieved using externally calibrated parallel imaging with comparable image quality. Acquisition time reductions are particularly large for fully phase-encoded methods such as spectrally resolved fully phase-encoded three-dimensional (3D) fast spin-echo (SR-FPE), in which scan time reductions of up to 8 min were obtained. A fully phase-encoded acquisition with broadband excitation and UTE enabled externally calibrated parallel imaging for 3D-MSI, eliminating the need for repeated calibration regions at each frequency offset. Significant reductions in acquisition time can be achieved, particularly for fully phase-encoded methods like SR-FPE. Magn Reson Med 77:2303-2309, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  4. He reemission implanted in metals

    Tanabe, T.

    2014-01-01

    Highlights: • Observation of He reemission of various metals under He + implantation at wide temperature range. • Materials examined are aluminum (Al), Nickel (Ni) and molybdenum (Mo). • He reemission is quite temperature dependent and different with materials. • Three metals show similar dependence on temperature normalized with respective melting point. • He reemission is successfully correlated with He behavior in metals. - Abstract: Helium (He) reemission of Al, Ni and Mo under energetic He implantation (10–30 keV) in wide temperature range is studied to understand behavior of implanted He in correlation with structure changes. The reemission behavior is categorized into 4 different temperature ranges with the normalized temperature (T m ) to the melting point of each metal. At elevated temperatures (well above ∼0.6 T m ), interstitial He atoms and/or He-vacancy (ies) clusters can migrate remaining no structure change and showing smooth reemission without any burst. Between ∼0.25 and 0.6 T m , He reemission always accompanies significant structure modification. For ∼04–0.6 T m , implanted He coalesce to make bubbles and the bubbles can move to the surface. Bubble migration accompanies materials flow to the surface resulting in fuzz surface or columnar structure, depending on implantation flux. Slower bubble motion at ∼0.25–0.4 prohibits the material migration. Instead the bubbles coalesce to grow large and multi-layered blistering appears as periodic reemission behavior. Below ∼0.25 T m , He migration is too slow for bubbles to grow large, but bubble density increases up to a certain fluence, where neighboring bubbles start to coalesce. Accordingly, He release is mostly caused by mechanical failure or blister rapture. With increasing fluence, all defects (bubbles and dislocation loops) tangle or inter connected with neighboring defects and accordingly He migration to the surface along the tangled or connected defects is enhanced

  5. [Cochlear implant treatment in Germany].

    Jacob, R; Stelzig, Y

    2013-01-01

    Restoration of impaired auditory function through cochlear implant is possible, with high reliably and great success. Nevertheless, there are regular disputes between patients and insurance companies due to high costs. In Germany, approx. 1.9 Mio. people are severely hearing impaired. It can be estimated that for adequate hearing rehabilitation about 30,000 cochlear implants/year are necessary. Currently, less than 10% of those affected are offered cochlear implant. A handicap is defined if there is deviation from normal hearing for more than 6 months. This sets a time frame for the supply with cochlear implant after sudden deafness. The professional code requires to advice all medical options to a person seeking help for hearing loss. This includes benefit-risk consideration. At this point, the economic aspect plays no role. The indication for medical treatment is only subject to the treating physician and should not be modified by non-physicians or organizations. It should be noted that a supply of hearing aids is qualitatively different to the help from a cochlear implant, which provides a restoration of lost function. In social law (SGB V and IX) doctors are requested to advise and recommend all measures which contribute to normal hearing (both sides). This indicates that doctors may be prosecuted for not offering help when medically possible, just because health insurance employees did not approve the cost balance. The current situation, with insufficient medical care for the hearing impaired, needs clarifying. To do this, patients, health insurance companies, the political institutions, legislation and professional societies need to accept their responsibilities.

  6. The classical equation of state of fully ionized plasmas

    Eisa, Dalia Ahmed

    2011-03-01

    The aim of this paper is to calculate the analytical form of the equation of state until the third virial coefficient of a classical system interacting via an effective potential of fully Ionized Plasmas. The excess osmotic pressure is represented in the forms of a convergent series expansions in terms of the plasma Parameter μ _{ab} = {{{e_a e_b χ } over {DKT}}}, where χ2 is the square of the inverse Debye radius. We consider only the thermal equilibrium plasma.

  7. Fully depleted back-illuminated p-channel CCD development

    Bebek, Chris J.; Bercovitz, John H.; Groom, Donald E.; Holland, Stephen E.; Kadel, Richard W.; Karcher, Armin; Kolbe, William F.; Oluseyi, Hakeem M.; Palaio, Nicholas P.; Prasad, Val; Turko, Bojan T.; Wang, Guobin

    2003-07-08

    An overview of CCD development efforts at Lawrence Berkeley National Laboratory is presented. Operation of fully-depleted, back-illuminated CCD's fabricated on high resistivity silicon is described, along with results on the use of such CCD's at ground-based observatories. Radiation damage and point-spread function measurements are described, as well as discussion of CCD fabrication technologies.

  8. An introduction to geometric theory of fully nonlinear parabolic equations

    Lunardi, A.

    1991-01-01

    We study a class of nonlinear evolution equations in general Banach space being an abstract version of fully nonlinear parabolic equations. In addition to results of existence, uniqueness and continuous dependence on the data, we give some qualitative results about stability of the stationary solutions, existence and stability of the periodic orbits. We apply such results to some parabolic problems arising from combustion theory. (author). 24 refs

  9. Printing Tablets with Fully Customizable Release Profiles for Personalized Medicine.

    Sun, Yajuan; Soh, Siowling

    2015-12-16

    Personalizing the release profiles of drugs is important for different people with different medical and biological conditions. A technically simple and low-cost method to fabricate fully customizable tablets that can deliver drugs with any type of release profile is described. The customization is intuitively straightforward: the desired profile can simply be "drawn" and printed by a 3D printer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Fully probabilistic control design in an adaptive critic framework

    Herzallah, R.; Kárný, Miroslav

    2011-01-01

    Roč. 24, č. 10 (2011), s. 1128-1135 ISSN 0893-6080 R&D Projects: GA ČR GA102/08/0567 Institutional research plan: CEZ:AV0Z10750506 Keywords : Stochastic control design * Fully probabilistic design * Adaptive control * Adaptive critic Subject RIV: BC - Control Systems Theory Impact factor: 2.182, year: 2011 http://library.utia.cas.cz/separaty/2011/AS/karny-0364820.pdf

  11. Fully Realistic Multi-Criteria Multi-Modal Routing

    Gündling, Felix; Keyhani, Mohammad Hossein; Schnee, Mathias; Weihe, Karsten

    2014-01-01

    We report on a multi-criteria search system, in which the German long- and short-distance trains, local public transport, walking, private car, private bike, and taxi are incorporated. The system is fully realistic. Three optimization criteria are addressed: travel time, travel cost, and convenience. Our algorithmic approach computes a complete Pareto set of reasonable connections. The computational study demonstrates that, even in such a large-scale, highly complex scenario, approp...

  12. On the uniqueness of fully informative rational expectations equilibria

    Peter DeMarzo; Costis Skiadas

    1998-01-01

    This paper analyzes two equivalent equilibrium notions under asymmetric information: risk neutral rational expectations equilibria (rn-REE), and common knowledge equilibria. We show that the set of fully informative rn-REE is a singleton, and we provide necessary and sufficient conditions for the existence of partially informative rn-REE. In a companion paper (DeMarzo and Skiadas (1996)) we show that equilibrium prices for the larger class of quasi-complete economies can be characterized as r...

  13. Devil's staircase in a fully frustrated superconducting array

    Kim, S.; Choi, M.Y.

    1993-01-01

    A two-dimensional fully frustrated superconducting array with a combined direct and alternating applied current is studied both analytically and numerically. At zero temperature equations of motion can be reduced through the use of the translational symmetry present in the system. Remarkably, we find a series of subharmonic steps in addition to standard integer and half-integer giant Shapiro steps, leading to devil's staircase structure. We also present results of detailed numerical simulations, which indeed reveal such subharmonic fine structure. (orig.)

  14. CMS on the GRID: Toward a fully distributed computing architecture

    Innocente, Vincenzo

    2003-01-01

    The computing systems required to collect, analyse and store the physics data at LHC would need to be distributed and global in scope. CMS is actively involved in several grid-related projects to develop and deploy a fully distributed computing architecture. We present here recent developments of tools for automating job submission and for serving data to remote analysis stations. Plans for further test and deployment of a production grid are also described

  15. Peri-implant esthetics assessment and management

    Balasubramaniam, Aarthi S.; Raja, Sunitha V.; Thomas, Libby John

    2013-01-01

    Providing an esthetic restoration in the anterior region of the mouth has been the basis of peri-implant esthetics. To achieve optimal esthetics, in implant supported restorations, various patient and tooth related factors have to be taken into consideration. Peri-implant plastic surgery has been adopted to improve the soft tissue and hard tissue profiles, during and after implant placement. The various factors and the procedures related to enhancement of peri-implant esthetics have been discussed in this review article. PMID:23878557

  16. Structural-chemical characteristics of implanted metals

    Kozejkin, B.V.; Pavlov, P.V.; Pitirimova, E.A.; Frolov, A.I.

    1988-01-01

    Corrosion and structural characteristics of metallic layers implanted by ions of chemically active impurities and noble gases are studied. Dependence of experimental results on parameters of initial materials and technological conditions of implantation is established. In studying corrosion characteristics of implanted metals a strong dependence of chemical passivation effect on technological conditions of ion-implantation and structure of initial material is stated. On the basis of developed mathematical model of chemical passivation effect it is shown that increase of corrosion characteristics of implanted metals is defined by superposition of surface and volumetric mechanisms

  17. Current Concepts in Restorative Implant Dentistry

    Prof.Marchack

    2009-01-01

    Patients today are incteasingly aware of dental implants.and their expectations are for esthetically and functionally pleasingimplant restorations that mimic natural teeth.This presentation will give both the experienced and novice practitioner a better understand-ing of how restorative implant dentistry has evolved.Treatment planning and restorative options for single implants.multiple implants andfully edentulons arches will be discussed,and the use of modern materials and CADCAM technology in fabricating the most contemporaryfixed implant supported prostheses will be demonstrated.

  18. Fully hadronic ttbar cross section measurement with ATLAS detector

    Bertella, Claudia

    2011-01-01

    The top quark pair production cross section in the fully hadronic final state is characterized by a six jet topology, two of which could be identified as originating from a b-quark using ATLAS b-tagging algorithms. Compared to other decay channels, this final state presents an advantageous larger branching ratio; on the other hand it suffers from a very large QCD multi-jet background, generally difficult to estimate from Monte Carlo simulation and therefore evaluated using data-driven techniques. The analysis is performed using 36pb-1 of pp collisions produced at the LHC with a center-of-mass energy of 7 TeV. The observed upper limit is set at 261 pb at 95% confidence level, where the expected Standard Model cross-section for the ttbar process is 165+11-16 pb. In the future, when the LHC luminosity increases, it is essential, to efficiently trigger on these fully hadronic ttbar events, to use dedicated triggers. An overview of the analysis for ttbar production cross section measurement in the fully hadronic f...

  19. Cardiac imaging: working towards fully-automated machine analysis & interpretation.

    Slomka, Piotr J; Dey, Damini; Sitek, Arkadiusz; Motwani, Manish; Berman, Daniel S; Germano, Guido

    2017-03-01

    Non-invasive imaging plays a critical role in managing patients with cardiovascular disease. Although subjective visual interpretation remains the clinical mainstay, quantitative analysis facilitates objective, evidence-based management, and advances in clinical research. This has driven developments in computing and software tools aimed at achieving fully automated image processing and quantitative analysis. In parallel, machine learning techniques have been used to rapidly integrate large amounts of clinical and quantitative imaging data to provide highly personalized individual patient-based conclusions. Areas covered: This review summarizes recent advances in automated quantitative imaging in cardiology and describes the latest techniques which incorporate machine learning principles. The review focuses on the cardiac imaging techniques which are in wide clinical use. It also discusses key issues and obstacles for these tools to become utilized in mainstream clinical practice. Expert commentary: Fully-automated processing and high-level computer interpretation of cardiac imaging are becoming a reality. Application of machine learning to the vast amounts of quantitative data generated per scan and integration with clinical data also facilitates a move to more patient-specific interpretation. These developments are unlikely to replace interpreting physicians but will provide them with highly accurate tools to detect disease, risk-stratify, and optimize patient-specific treatment. However, with each technological advance, we move further from human dependence and closer to fully-automated machine interpretation.

  20. Fully implicit 1D radiation hydrodynamics: Validation and verification

    Ghosh, Karabi; Menon, S.V.G.

    2010-01-01

    A fully implicit finite difference scheme has been developed to solve the hydrodynamic equations coupled with radiation transport. Solution of the time-dependent radiation transport equation is obtained using the discrete ordinates method and the energy flow into the Lagrangian meshes as a result of radiation interaction is fully accounted for. A tridiagonal matrix system is solved at each time step to determine the hydrodynamic variables implicitly. The results obtained from this fully implicit radiation hydrodynamics code in the planar geometry agrees well with the scaling law for radiation driven strong shock propagation in aluminium. For the point explosion problem the self similar solutions are compared with results for pure hydrodynamic case in spherical geometry. Results obtained when radiation interaction is also accounted agree with those of point explosion with heat conduction for lower input energies. Having, thus, benchmarked the code, self convergence of the method w.r.t. time step is studied in detail for both the planar and spherical problems. Spatial as well as temporal convergence rates are ≅1 as expected from the difference forms of mass, momentum and energy conservation equations. This shows that the asymptotic convergence rate of the code is realized properly.

  1. Fully integrated digital GAMMA camera-computer system

    Berger, H.J.; Eisner, R.L.; Gober, A.; Plankey, M.; Fajman, W.

    1985-01-01

    Although most of the new non-nuclear imaging techniques are fully digital, there has been a reluctance in nuclear medicine to abandon traditional analog planar imaging in favor of digital acquisition and display. The authors evaluated a prototype digital camera system (GE STARCAM) in which all of the analog acquisition components are replaced by microprocessor controls and digital circuitry. To compare the relative effects of acquisition matrix size on image quality and to ascertain whether digital techniques could be used in place of analog imaging, Tc-99m bone scans were obtained on this digital system and on a comparable analog camera in 10 patients. The dedicated computer is used for camera setup including definition of the energy window, spatial energy correction, and spatial distortion correction. The display monitor, which is used for patient positioning and image analysis, is 512/sup 2/ non-interlaced, allowing high resolution imaging. Data acquisition and processing can be performed simultaneously. Thus, the development of a fully integrated digital camera-computer system with optimized display should allow routine utilization of non-analog studies in nuclear medicine and the ultimate establishment of fully digital nuclear imaging laboratories

  2. Soft Ultrathin Electronics Innervated Adaptive Fully Soft Robots.

    Wang, Chengjun; Sim, Kyoseung; Chen, Jin; Kim, Hojin; Rao, Zhoulyu; Li, Yuhang; Chen, Weiqiu; Song, Jizhou; Verduzco, Rafael; Yu, Cunjiang

    2018-03-01

    Soft robots outperform the conventional hard robots on significantly enhanced safety, adaptability, and complex motions. The development of fully soft robots, especially fully from smart soft materials to mimic soft animals, is still nascent. In addition, to date, existing soft robots cannot adapt themselves to the surrounding environment, i.e., sensing and adaptive motion or response, like animals. Here, compliant ultrathin sensing and actuating electronics innervated fully soft robots that can sense the environment and perform soft bodied crawling adaptively, mimicking an inchworm, are reported. The soft robots are constructed with actuators of open-mesh shaped ultrathin deformable heaters, sensors of single-crystal Si optoelectronic photodetectors, and thermally responsive artificial muscle of carbon-black-doped liquid-crystal elastomer (LCE-CB) nanocomposite. The results demonstrate that adaptive crawling locomotion can be realized through the conjugation of sensing and actuation, where the sensors sense the environment and actuators respond correspondingly to control the locomotion autonomously through regulating the deformation of LCE-CB bimorphs and the locomotion of the robots. The strategy of innervating soft sensing and actuating electronics with artificial muscles paves the way for the development of smart autonomous soft robots. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Robust Fully Distributed Minibatch Gradient Descent with Privacy Preservation

    Gábor Danner

    2018-01-01

    Full Text Available Privacy and security are among the highest priorities in data mining approaches over data collected from mobile devices. Fully distributed machine learning is a promising direction in this context. However, it is a hard problem to design protocols that are efficient yet provide sufficient levels of privacy and security. In fully distributed environments, secure multiparty computation (MPC is often applied to solve these problems. However, in our dynamic and unreliable application domain, known MPC algorithms are not scalable or not robust enough. We propose a light-weight protocol to quickly and securely compute the sum query over a subset of participants assuming a semihonest adversary. During the computation the participants learn no individual values. We apply this protocol to efficiently calculate the sum of gradients as part of a fully distributed minibatch stochastic gradient descent algorithm. The protocol achieves scalability and robustness by exploiting the fact that in this application domain a “quick and dirty” sum computation is acceptable. We utilize the Paillier homomorphic cryptosystem as part of our solution combined with extreme lossy gradient compression to make the cost of the cryptographic algorithms affordable. We demonstrate both theoretically and experimentally, based on churn statistics from a real smartphone trace, that the protocol is indeed practically viable.

  4. The influence of direct laser metal sintering implants on the early stages of osseointegration in diabetic mini-pigs.

    Tan, Naiwen; Liu, Xiangwei; Cai, Yanhui; Zhang, Sijia; Jian, Bo; Zhou, Yuchao; Xu, Xiaoru; Ren, Shuai; Wei, Hongbo; Song, Yingliang

    2017-01-01

    High failure rates of oral implants have been reported in diabetic patients due to the disruption of osseointegration. The aim of this study was to investigate whether direct laser metal sintering (DLMS) could improve osseointegration in diabetic animal models. Surface characterizations were carried out on two types of implants. Cell morphology and the osteogenic-related gene expression of MG63 cells were observed under conditions of DLMS and microarc oxidation (MAO). A diabetes model in mini-pigs was established by intravenous injection of streptozotocin (150 mg/kg), and a total of 36 implants were inserted into the mandibular region. Micro-computed tomography (micro-CT) and histologic evaluations were performed 3 and 6 months after implantation. The Ra (the average of the absolute height of all points) of MAO surface was 2.3±0.3 µm while the DLMS surface showed the Ra of 27.4±1.1 µm. The cells on DLMS implants spread out more podia than those on MAO implants through cell morphology analysis. Osteogenic-related gene expression was also dramatically increased in the DLMS group. Obvious improvement was observed in the micro-CT and Van Gieson staining analyses of DLMS implants compared with MAO at 3 months, although this difference disappeared by 6 months. DLMS implants showed a higher bone-implant contact percentage (33.2%±11.2%) at 3 months compared with MAO group (18.9%±7.3%) while similar results were showed at 6 months between DLMS group (42.8%±10.1%) and MAO group (38.3%±10.8%). The three-dimensional environment of implant surfaces with highly porous and fully interconnected channel and pore architectures can improve cell spreading and accelerate the progress of osseointegration in diabetic mini-pigs.

  5. Poly Implants Prosthèse Breast Implants: A Case Series and Review of the Literature.

    Klein, Doron; Hadad, Eran; Wiser, Itay; Wolf, Omer; Itzhaki Shapira, Ortal; Fucks, Shir; Heller, Lior

    2018-01-01

    Silicone breast implants from the French manufacturer Poly Implants Prosthèse (PIP) were recalled from the European market after the French regulator has revealed the implants contain non-medical-grade silicone filler. In December 2011, following a large increase in reported rupture rate and a possible cancer risk, the French Ministry of Health recommended consideration of the PIP explantation, regardless of their condition. In 2012, the Israel Ministry of Health recommended to replace the implants only upon suspected implant rupture. The aims of this study were to characterize breast-augmented Israeli patients with PIP implants, compare their outcomes with those of breast-augmented patients with different implant types, and review the current PIP literature. Breast-augmented patients who underwent an elective breast implant exchange in Israel between January 2011 and January 2017 were included in the study. Data were collected from electronic and physical medical files. There were 73 breast-augmented female patients with 146 PIP breast implants included in this study. Average implant age was 6.7 ± 2.79 years. Mean implant size was 342.8 ± 52.9 mL. Fourteen women (19 implants [16%]) had a high-grade capsular contracture (Baker grade 3-4). During exchange, 28 implants were found to be ruptured (19.2%). Less than 10 years following breast augmentation, PIP implants demonstrated higher rupture rate compared with other implants. Our data are comparable to overall available rupture rate. Among patients with definitive rupture diagnosis, an elective implant removal should be recommended. In cases of undamaged implants, plastic surgeons should also seriously consider PIP implant explantation. When the patient does not desire to remove the implant, an annual physical examination and breast ultrasound are recommended, beginning a year after augmentation.

  6. [Clinical application of individualized three-dimensional printing implant template in multi-tooth dental implantation].

    Wang, Lie; Chen, Zhi-Yuan; Liu, Rong; Zeng, Hao

    2017-08-01

    To study the value and satisfaction of three-dimensional printing implant template and conventional implant template in multi-tooth dental implantation. Thirty cases (83 teeth) with missing teeth needing to be implanted were randomly divided into conventional implant template group (CIT group, 15 cases, 42 teeth) and 3D printing implant template group (TDPIT group, 15 cases, 41 teeth). Patients in CIT group were operated by using conventional implant template, while patients in TDPIT group were operated by using three-dimensional printing implant template. The differences of implant neck and tip deviation, implant angle deviation and angle satisfaction between the two groups were compared. The difference of probing depth and bone resorption of implant were compared 1 year after operation between the two groups. The difference of success rate and satisfaction of dental implantation were compared 1 year after operation between the two groups. SPSS19.0 software package was used for statistical analysis. The deviation direction of the neck and the tip in disto-mesial, bucco-palatal, vertical direction and angle of implants in disto-mesial and bucco-palatal direction in TDPIT group were significantly lower than in CIT group (P0.05). The difference of the cumulative success rate in dental implantation at 3 months and 6 months between the two groups were not significant (P>0.05), but the cumulative success rate of TDPIT group was significantly higher than CIT group at 9 months and 1 year (90.48% vs 100%,P=0.043). The patients' satisfaction rate of dental implantation in TDPIT group was significantly higher than in CIT group (86.67% vs 53.33%, P=0.046). Using three-dimensional printing implant template can obtain better accuracy of implant, higher implant success rate and better patients' satisfaction than using conventional implant template. It is suitable for clinical application.

  7. Clinical feasibility of a new through-the-scope fully covered esophageal self-expandable metallic stent: an in vivo animal study.

    Cheon, Young Koog; Lee, Tae Yoon; Sung, In Kyung; Shim, Chan Sup

    2014-01-01

    Most delivery devices used for esophageal stents for obstructing esophageal cancer have a diameter of 5-8 mm, a size that is too large to pass through the endoscopic working channel. The conventional esophageal stent requires multiple endoscopic procedures for implantation. The purpose of the present study was to evaluate the clinical feasibility of a newly developed fully covered, self-expanding, through-the-scope (TTS) esophageal stent in a porcine model. Eight mini pigs were used. Each animal underwent placement of a fully covered TTS stent (Hanarostent® Esophagus TTS) and the upper part of the stent was fixed by suturing with nylon. Fluoroscopy was carried out every week to assess migration of the stent. Follow-up endoscopy was done every month for 3 months to evaluate the status of the membrane, stent mesh, grade of tissue hyperplasia, and mucosal changes at both ends of the stent. All stents were successfully and easily deployed, and were placed without any distortion in the stent or without rupture of the membrane. In two cases, stent migration was observed after 8 weeks. No case of membrane disruption, stent mesh disruption or tissue hyperplasia at either end of the stent was found at the completion of the study. Our findings indicate that the new fully covered self-expanding TTS esophageal stent is easy and simple to implant, and no significant distortion of mesh or disruption of membrane was observed. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  8. Ion implantation and bio-compatibility

    Suzuki, Yoshiaki; Kusakabe, Masahiro [Sony Corp., Tokyo (Japan). Corporate Research Labs.; Iwaki, Masaya

    1992-07-01

    Surface modification of polymers by ion implantation has been carried out to control surface properties such as conductivity, wettability, blood and tissue compatibility. Ion implantation into silicone rubber, polystyrene and segmented polyurethane was performed at 150 keV with doses ranging from 1 x 10[sup 15] to 3 x 10[sup 17] ions/cm[sup 2] to improve bio-compatibility. The platelet accumulation on ion implanted silicone rubber decreased and non-thrombogenicity of ion implanted specimens were improved. The ion implanted polystyrene and segmented polyurethane have been found to exhibit remarkably higher adhesion and spreading of endothelial cells compared to the non-implanted case. It is concluded that ion implantation into polymers is effective in controlling their bio-compatibility. (author).

  9. Congenitally Deafblind Children and Cochlear Implants

    Dammeyer, Jesper Herup

    2008-01-01

    There has been much research conducted demonstrating the positive benefits of cochlear implantation (CI) in children who are deaf. Research on cochlear implantation in children who are both deaf and blind, however, is lacking. The purpose of this article is to present a study of 5 congenitally...... deafblind children who received cochlear implants between 2.2 and 4.2 years of age.  Ratings of video observations were used to measure the children's early communication development with and without the use of their cochlear implants. In addition, parental interviews were used to assess the benefits...... parents perceived regarding their children's cochlear implants. Two examples are included in this article to illustrate the parents' perspectives about cochlear implantation in their deafblind children. Benefits of cochlear implantation in this cohort of children included improved attention and emotional...

  10. Dynamics of bone graft healing around implants

    Narayan Venkataraman

    2015-01-01

    A few questions arise pertaining to the use of bone grafts along with implants are whether these are successful in approximation with implant. Do they accelerate bone regeneration? Are all defects ultimately regenerated with new viable bone? Is the bone graft completely resorbed or integrated in new bone? Does the implant surface characteristic positively affect osseointegration when used with a bone graft? What type of graft and implant surface can be used that will have a positive effect on the healing type and time? Finally, what are the dynamics of bone graft healing around an implant? This review discusses the cellular and molecular mechanisms of bone graft healing in general and in vicinity of another foreign, avascular body, namely the implant surface, and further, the role of bone grafts in osseointegration and/or clinical success of the implants.

  11. Magnetic resonance imaging of breast implants.

    Shah, Mala; Tanna, Neil; Margolies, Laurie

    2014-12-01

    Silicone breast implants have significantly evolved since their introduction half a century ago, yet implant rupture remains a common and expected complication, especially in patients with earlier-generation implants. Magnetic resonance imaging is the primary modality for assessing the integrity of silicone implants and has excellent sensitivity and specificity, and the Food and Drug Administration currently recommends periodic magnetic resonance imaging screening for silent silicone breast implant rupture. Familiarity with the types of silicone implants and potential complications is essential for the radiologist. Signs of intracapsular rupture include the noose, droplet, subcapsular line, and linguine signs. Signs of extracapsular rupture include herniation of silicone with a capsular defect and extruded silicone material. Specific sequences including water and silicone suppression are essential for distinguishing rupture from other pathologies and artifacts. Magnetic resonance imaging provides valuable information about the integrity of silicone implants and associated complications.

  12. Surface modification of implants in long bone.

    Förster, Yvonne; Rentsch, Claudia; Schneiders, Wolfgang; Bernhardt, Ricardo; Simon, Jan C; Worch, Hartmut; Rammelt, Stefan

    2012-01-01

    Coatings of orthopedic implants are investigated to improve the osteoinductive and osteoconductive properties of the implant surfaces and thus to enhance periimplant bone formation. By applying coatings that mimic the extracellular matrix a favorable environment for osteoblasts, osteoclasts and their progenitor cells is provided to promote early and strong fixation of implants. It is known that the early bone ongrowth increases primary implant fixation and reduces the risk of implant failure. This review presents an overview of coating titanium and hydroxyapatite implants with components of the extracellular matrix like collagen type I, chondroitin sulfate and RGD peptide in different small and large animal models. The influence of these components on cells, the inflammation process, new bone formation and bone/implant contact is summarized.

  13. Release of low molecular weight silicones and platinum from silicone breast implants.

    Lykissa, E D; Kala, S V; Hurley, J B; Lebovitz, R M

    1997-12-01

    also observed to leak through intact implants into lipid-containing media at rates of approximately 20-25 micrograms/day/250 g of implant at 37 degrees C. The rates at which both LM-silicones and platinum have been observed to leak from intact implants could lead to significant accumulation within lipid-rich tissues and should be investigated more fully in vivo.

  14. Translation of First North American 50 and 70 cc Total Artificial Heart Virtual and Clinical Implantations: Utility of 3D Computed Tomography to Test Fit Devices.

    Ferng, Alice S; Oliva, Isabel; Jokerst, Clinton; Avery, Ryan; Connell, Alana M; Tran, Phat L; Smith, Richard G; Khalpey, Zain

    2017-08-01

    Since the creation of SynCardia's 50 cc Total Artificial Hearts (TAHs), patients with irreversible biventricular failure now have two sizing options. Herein, a case series of three patients who have undergone successful 50 and 70 cc TAH implantation with complete closure of the chest cavity utilizing preoperative "virtual implantation" of different sized devices for surgical planning are presented. Computed tomography (CT) images were used for preoperative planning prior to TAH implantation. Three-dimensional (3D) reconstructions of preoperative chest CT images were generated and both 50 and 70 cc TAHs were virtually implanted into patients' thoracic cavities. During the simulation, the TAHs were projected over the native hearts in a similar position to the actual implantation, and the relationship between the devices and the atria, ventricles, chest wall, and diaphragm were assessed. The 3D reconstructed images and virtual modeling were used to simulate and determine for each patient if the 50 or 70 cc TAH would have a higher likelihood of successful implantation without complications. Subsequently, all three patients received clinical implants of the properly sized TAH based on virtual modeling, and their chest cavities were fully closed. This virtual implantation increases our confidence that the selected TAH will better fit within the thoracic cavity allowing for improved surgical outcome. Clinical implantation of the TAHs showed that our virtual modeling was an effective method for determining the correct fit and sizing of 50 and 70 cc TAHs. © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  15. Dopant redistribution and electrical activation in silicon following ultra-low energy boron implantation and excimer laser annealing

    Whelan, S.; La Magna, A.; Privitera, V.; Mannino, G.; Italia, M.; Bongiorno, C.; Fortunato, G.; Mariucci, L.

    2003-01-01

    Excimer laser annealing (ELA) of ultra-low-energy (ULE) B-ion implanted Si has been performed. High-resolution transmission electron microscopy has been used to assess the as-implanted damage and the crystal recovery following ELA. The electrical activation and redistribution of B in Si during ELA has been investigated as a function of the laser energy density (melted depth), the implant dose, and the number of laser pulses (melt time). The activated and retained dose has been evaluated with spreading resistance profiling and secondary ion mass spectrometry. A significant amount of the implanted dopant was lost from the sample during ELA. However, the dopant that was retained in crystal material was fully activated following rapid resolidification. At an atomic concentration below the thermodynamic limit, the activation efficiency (dose activated/dose implanted into Si material) was a constant for a fixed melt depth, irrespective of the dose implanted and hence the total activated dose was raised as the implant dose was increased. The electrical activation was increased for high laser energy density annealing when the dopant was redistributed over a deeper range

  16. Successful Rehabilitation of Partial Edentulous Maxilla and Mandible with New Type of Implants: Molecular Precision Implants

    Matteo Danza

    2014-01-01

    Full Text Available The extraction of teeth results in rapid bone resorption both vertically and horizontally in the first month. The loss of alveolar ridge reduces the chance of implant rehabilitation. Atraumatic extraction, implant placement in extraction socket, and an immediate prosthesis have been proposed as alternative therapies to maintain the volume and contours tissue and reduce time and cost of treatment. The immediate load of implants is a universally practiced procedure; nevertheless a successful procedure requires expertise in both the clinical and the reconstructive stages using a solid implant system. Excellent primary stability and high bone-implant contact are only minimal requirements for any type of implant procedure. In this paper we present a case report using a new type of implants. The new type of implants, due to its sophisticated control system of production, provides to the implantologist a safe and reliable implant, with a macromorphology designed to ensure a close contact with the surrounding bone.

  17. Does the number of implants have any relation with peri-implant disease?

    Bernardo Born PASSONI

    2014-10-01

    Full Text Available Objective: The aim of this study was to evaluate the relationship between the number of pillar implants of implant-supported fixed prostheses and the prevalence of periimplant disease. Material and Methods: Clinical and radiographic data were obtained for the evaluation. The sample consisted of 32 patients with implant-supported fixed prostheses in function for at least one year. A total of 161 implants were evaluated. Two groups were formed according to the number of implants: G1 ≤5 implants and G2 >5 implants. Data collection included modified plaque index (MPi, bleeding on probing (BOP, probing depth (PD, width of keratinized mucosa (KM and radiographic bone loss (BL. Clinical and radiographic data were grouped for each implant in order to conduct the diagnosis of mucositis or peri-implantitis. Results: Clinical parameters were compared between groups using Student’s t test for numeric variables (KM, PD and BL and Mann-Whitney test for categorical variables (MPi and BOP. KM and BL showed statistically significant differences between both groups (p<0.001. Implants from G1 – 19 (20.43% – compared with G2 – 26 (38.24% – showed statistically significant differences regarding the prevalence of peri-implantitis (p=0.0210. Conclusion: It seems that more than 5 implants in total fixed rehabilitations increase bone loss and consequently the prevalence of implants with periimplantitis. Notwithstanding, the number of implants does not have any influence on the prevalence of mucositis.

  18. Comparative silicone breast implant evaluation using mammography, sonography, and magnetic resonance imaging: experience with 59 implants.

    Ahn, C Y; DeBruhl, N D; Gorczyca, D P; Shaw, W W; Bassett, L W

    1994-10-01

    With the current controversy regarding the safety of silicone implants, the detection and evaluation of implant rupture are causing concern for both plastic surgeons and patients. Our study obtained comparative value analysis of mammography, sonography, and magnetic resonance imaging (MRI) in the detection of silicone implant rupture. Twenty-nine symptomatic patients (total of 59 silicone implants) were entered into the study. Intraoperative findings revealed 21 ruptured implants (36 percent). During physical examination, a positive "squeeze test" was highly suggestive of implant rupture. Mammograms were obtained of 51 implants (sensitivity 11 percent, specificity 89 percent). Sonography was performed on 57 implants (sensitivity 70 percent, specificity 92 percent). MRI was performed on 55 implants (sensitivity 81 percent, specificity 92 percent). Sonographically, implant rupture is demonstrated by the "stepladder sign." Double-lumen implants may appear as false-positive results for rupture on sonography. On MRI, the "linguine sign" represents disrupted fragments of a ruptured implant. The most reliable imaging modality for implant rupture detection is MRI, followed by sonogram. Mammogram is the least reliable. Our study supports the clinical indication and diagnostic value of sonogram and MRI in the evaluation of symptomatic breast implant patients.

  19. Continuously Operating Biosensor and Its Integration into a Hermetically Sealed Medical Implant

    Mario Birkholz

    2016-10-01

    Full Text Available An integration concept for an implantable biosensor for the continuous monitoring of blood sugar levels is presented. The system architecture is based on technical modules used in cardiovascular implants in order to minimize legal certification efforts for its perspective usage in medical applications. The sensor chip operates via the principle of affinity viscometry, which is realized by a fully embedded biomedical microelectromechanical systems (BioMEMS prepared in 0.25-µm complementary metal–oxide–semiconductor (CMOS/BiCMOS technology. Communication with a base station is established in the 402–405 MHz band used for medical implant communication services (MICS. The implant shall operate within the interstitial tissue, and the hermetical sealing of the electronic system against interaction with the body fluid is established using titanium housing. Only the sensor chip and the antenna are encapsulated in an epoxy header closely connected to the metallic housing. The study demonstrates that biosensor implants for the sensing of low-molecular-weight metabolites in the interstitial may successfully rely on components already established in cardiovascular implantology.

  20. Dental implants modified with drug releasing titania nanotubes: therapeutic potential and developmental challenges.

    Gulati, Karan; Ivanovski, Sašo

    2017-08-01

    The transmucosal nature of dental implants presents a unique therapeutic challenge, requiring not only rapid establishment and subsequent maintenance of osseointegration, but also the formation of resilient soft tissue integration. Key challenges in achieving long-term success are sub-optimal bone integration in compromised bone conditions and impaired trans-mucosal tissue integration in the presence of a persistent oral microbial biofilm. These challenges can be targeted by employing a drug-releasing implant modification such as TiO 2 nanotubes (TNTs), engineered on titanium surfaces via electrochemical anodization. Areas covered: This review focuses on applications of TNT-based dental implants towards achieving optimal therapeutic efficacy. Firstly, the functions of TNT implants will be explored in terms of their influence on osseointegration, soft tissue integration and immunomodulation. Secondly, the developmental challenges associated with such implants are reviewed including sterilization, stability and toxicity. Expert opinion: The potential of TNTs is yet to be fully explored in the context of the complex oral environment, including appropriate modulation of alveolar bone healing, immune-inflammatory processes, and soft tissue responses. Besides long-term in vivo assessment under masticatory loading conditions, investigating drug-release profiles in vivo and addressing various technical challenges are required to bridge the gap between research and clinical dentistry.

  1. Erbium implantation in Strontium Titanate

    Araújo, J P; Alves, E; Correia, J G; Monteiro, T; Soares, J; Santos, L

    2002-01-01

    We report on the lattice location of Er in SrTiO$_{3}$ single crystals using the emission channeling technique. The angular distribution of conversion electrons emitted from $^{167m}$Er(T$_{1/2}$=2.27 s) was monitored with a position-sensitive detector following the room-temperature 60 keV implantation of the precursor isotope $^{167}$Tm(T$_{1/2}$=9.25 d) to a dose of 2$\\times$ 10$^{12}$ at./cm$^{2}$. The results for the sample annealed in vacuum at 610°C for 15 min provide direct evidence that Er occupies both Sr and Ti substitutional lattice sites. In addition, thermal recovery of lattice damage was also studied with RBS/C for SrTiO$_{3}$ implanted to doses of 5$\\times$ 10$^{14}$ and 5 $\\times$ 10$^{15}$ Er/cm$^{2}$. We further comment on preliminary photoluminescence results from these samples.

  2. A fully adaptive hybrid optimization of aircraft engine blades

    Dumas, L.; Druez, B.; Lecerf, N.

    2009-10-01

    A new fully adaptive hybrid optimization method (AHM) has been developed and applied to an industrial problem in the field of the aircraft engine industry. The adaptivity of the coupling between a global search by a population-based method (Genetic Algorithms or Evolution Strategies) and the local search by a descent method has been particularly emphasized. On various analytical test cases, the AHM method overperforms the original global search method in terms of computational time and accuracy. The results obtained on the industrial case have also confirmed the interest of AHM for the design of new and original solutions in an affordable time.

  3. Multigrid Methods for Fully Implicit Oil Reservoir Simulation

    Molenaar, J.

    1996-01-01

    In this paper we consider the simultaneous flow of oil and water in reservoir rock. This displacement process is modeled by two basic equations: the material balance or continuity equations and the equation of motion (Darcy's law). For the numerical solution of this system of nonlinear partial differential equations there are two approaches: the fully implicit or simultaneous solution method and the sequential solution method. In the sequential solution method the system of partial differential equations is manipulated to give an elliptic pressure equation and a hyperbolic (or parabolic) saturation equation. In the IMPES approach the pressure equation is first solved, using values for the saturation from the previous time level. Next the saturations are updated by some explicit time stepping method; this implies that the method is only conditionally stable. For the numerical solution of the linear, elliptic pressure equation multigrid methods have become an accepted technique. On the other hand, the fully implicit method is unconditionally stable, but it has the disadvantage that in every time step a large system of nonlinear algebraic equations has to be solved. The most time-consuming part of any fully implicit reservoir simulator is the solution of this large system of equations. Usually this is done by Newton's method. The resulting systems of linear equations are then either solved by a direct method or by some conjugate gradient type method. In this paper we consider the possibility of applying multigrid methods for the iterative solution of the systems of nonlinear equations. There are two ways of using multigrid for this job: either we use a nonlinear multigrid method or we use a linear multigrid method to deal with the linear systems that arise in Newton's method. So far only a few authors have reported on the use of multigrid methods for fully implicit simulations. Two-level FAS algorithm is presented for the black-oil equations, and linear multigrid for

  4. Multigrid methods for fully implicit oil reservoir simulation

    Molenaar, J.

    1995-12-31

    In this paper, the authors consider the simultaneous flow of oil and water in reservoir rock. This displacement process is modeled by two basic equations the material balance or continuity equations, and the equation of motion (Darcy`s law). For the numerical solution of this system of nonlinear partial differential equations, there are two approaches: the fully implicit or simultaneous solution method, and the sequential solution method. In this paper, the authors consider the possibility of applying multigrid methods for the iterative solution of the systems of nonlinear equations.

  5. Electronically Tunable Fully Integrated Fractional-Order Resonator

    Tsirimokou, Georgia

    2017-03-20

    A fully integrated implementation of a parallel fractional-order resonator which employs together a fractional order capacitor and a fractional-order inductor is proposed in this paper. The design utilizes current-controlled Operational Transconductance Amplifiers as building blocks, designed and fabricated in AMS 0:35m CMOS process, and based on a second-order approximation of a fractional-order differentiator/ integrator magnitude optimized in the range 10Hz–700Hz. An attractive benefit of the proposed scheme is its electronic tuning capability.

  6. Uniformity of fully gravure printed organic field-effect transistors

    Hambsch, M.; Reuter, K.; Stanel, M.; Schmidt, G.; Kempa, H.; Fuegmann, U.; Hahn, U.; Huebler, A.C.

    2010-01-01

    Fully mass-printed organic field-effect transistors were made completely by means of gravure printing. Therefore a special printing layout was developed in order to avoid register problems in print direction. Upon using this layout, contact pads for source-drain electrodes of the transistors are printed together with the gate electrodes in one and the same printing run. More than 50,000 transistors have been produced and by random tests a yield of approximately 75% has been determined. The principle suitability of the gravure printed transistors for integrated circuits has been shown by the realization of ring oscillators.

  7. A fully robust PARAFAC method for analyzing fluorescence data

    Engelen, Sanne; Frosch, Stina; Jørgensen, Bo

    2009-01-01

    and Rayleigh scatter. Recently, a robust PARAFAC method that circumvents the harmful effects of outlying samples has been developed. For removing the scatter effects on the final PARAFAC model, different techniques exist. Newly, an automated scatter identification tool has been constructed. However......, there still exists no robust method for handling fluorescence data encountering both outlying EEM landscapes and scatter. In this paper, we present an iterative algorithm where the robust PARAFAC method and the scatter identification tool are alternately performed. A fully automated robust PARAFAC method...

  8. Application of ANNs approach for solving fully fuzzy polynomials system

    R. Novin

    2017-11-01

    Full Text Available In processing indecisive or unclear information, the advantages of fuzzy logic and neurocomputing disciplines should be taken into account and combined by fuzzy neural networks. The current research intends to present a fuzzy modeling method using multi-layer fuzzy neural networks for solving a fully fuzzy polynomials system. To clarify the point, it is necessary to inform that a supervised gradient descent-based learning law is employed. The feasibility of the method is examined using computer simulations on a numerical example. The experimental results obtained from the investigation of the proposed method are valid and delivers very good approximation results.

  9. Hyperon-Nulceon Scattering from Fully-Dynamical Lattice QCD

    Silas Beane; Paulo Bedaque; Thomas Luu; Konstantinos Orginos; Elizabetta Pallante; Assumpta Parreno; Martin Savage

    2007-10-01

    We present results of the first fully-dynamical lattice QCD determination of hyperon-nucleon scattering. One s-wave phase shift was determined for n{Lambda} scattering in both spin-channels at pion masses of 350, 490, and 590 MeV, and for n{Sigma}^- scattering in both spin channels at pion masses of 490, and 590 MeV. The calculations were performed with domain-wall valence quarks on dynamical, staggered gauge configurations with a lattice spacing of b ~0.125 fm.

  10. Monte Carlo simulation of fully Markovian stochastic geometries

    Lepage, Thibaut; Delaby, Lucie; Malvagi, Fausto; Mazzolo, Alain

    2010-01-01

    The interest in resolving the equation of transport in stochastic media has continued to increase these last years. For binary stochastic media it is often assumed that the geometry is Markovian, which is never the case in usual environments. In the present paper, based on rigorous mathematical theorems, we construct fully two-dimensional Markovian stochastic geometries and we study their main properties. In particular, we determine a percolation threshold p c , equal to 0.586 ± 0.0015 for such geometries. Finally, Monte Carlo simulations are performed through these geometries and the results compared to homogeneous geometries. (author)

  11. Moving towards a Competitive Fully Enzymatic Biodiesel Process

    Silvia Cesarini

    2015-06-01

    Full Text Available Enzymatic biodiesel synthesis can solve several problems posed by the alkaline-catalyzed transesterification but it has the drawback of being too expensive to be considered competitive. Costs can be reduced by lipase improvement, use of unrefined oils, evaluation of soluble/immobilized lipase preparations, and by combination of phospholipases with a soluble lipase for biodiesel production in a single step. As shown here, convenient natural tools have been developed that allow synthesis of high quality FAMEs (EN14214 from unrefined oils in a completely enzymatic single-step process, making it fully competitive.

  12. Electronically Tunable Fully Integrated Fractional-Order Resonator

    Tsirimokou, Georgia; Psychalinos, Costas; Elwakil, Ahmed S.; Salama, Khaled N.

    2017-01-01

    A fully integrated implementation of a parallel fractional-order resonator which employs together a fractional order capacitor and a fractional-order inductor is proposed in this paper. The design utilizes current-controlled Operational Transconductance Amplifiers as building blocks, designed and fabricated in AMS 0:35m CMOS process, and based on a second-order approximation of a fractional-order differentiator/ integrator magnitude optimized in the range 10Hz–700Hz. An attractive benefit of the proposed scheme is its electronic tuning capability.

  13. Implantable Neural Interfaces for Sharks

    2007-05-01

    technology for recording and stimulating from the auditory and olfactory sensory nervous systems of the awake, swimming nurse shark , G. cirratum (Figures...overlay of the central nervous system of the nurse shark on a horizontal MR image. Implantable Neural Interfaces for Sharks ...Neural Interfaces for Characterizing Population Responses to Odorants and Electrical Stimuli in the Nurse Shark , Ginglymostoma cirratum.” AChemS Abs

  14. Tooth Retained Implant: No More an Oxymoron

    Divya Bhat

    2011-03-01

    Full Text Available Introduction: Periodontally af-fected teeth are treated in one of the two ways. (1 Tooth retention after periodontal surgery, in which the degree of regeneration achieved is unpredictable. (2 Tooth extrac-tion and implant placement. Implants have an osseointegrated surface which does not provide adequate shock absorption. Regeneration can be achieved by resecting the crown of the affected tooth and submerging the root. This technique has not had a clinical application so far as the tooth becomes difficult to restore. Placing an implant within the root can make the retained root restorable. At the same time, as the implant is placed within the root surface it achieves a periodontal integration which dampens occlusal forces better than osseointegration. Therefore, such a “tooth retained implant” may serve as an additional treatment option with significant benefits over tooth retention and implant placement alone. The hypothesis: Implants placed within retained roots have shown cementum deposition and attachment of periodontal ligament fibers over their surface. This periodontal attachment may be able to dam-pen forces better than in an osseointegrated implant. Moreover, since an implant is being placed, the crown of the tooth can be resected and submerged. This prevents epithelial migration, allows for the periodontal ligament cells to populate the wound and favors regeneration.Evaluation of the hypothesis: The technique of placing implants within cavities prepared in the root and then submerging them are simple for any practitioner placing implants routinely.

  15. R&D on dental implants breakage

    Croitoru, Sorin Mihai; Popovici, Ion Alexandru

    2017-09-01

    Most used dental implants for human dental prostheses are of two steps type: first step means implantation and, after several months healing and osseointegration, second step is prosthesis fixture. For sure, dental implants and prostheses are meant to last for a lifetime. Still, there are unfortunate cases when dental implants break. This paper studies two steps dental implants breakage and proposes a set of instruments for replacement and restoration of the broken implant. First part of the paper sets the input data of the study: structure of the studied two steps dental implants based on two Romanian patents and values of the loading forces found in practice and specialty papers. In the second part of the paper, using DEFORM 2D™ FEM simulation software, worst case scenarios of loading dental implants are studied in order to determine which zones and components of the dental implant set are affected (broken). Last part of the paper is dedicated to design and presentation of a set for extracting and cutting tools used to restore the broken implant set.

  16. Management of peri-implant infections

    K L Vandana

    2015-01-01

    Full Text Available The ever-increasing popularity of dental implants in recent years has been associated with the reported incidence of short-term and long-term complications such as peri-implant mucositis and peri-implantitis. Therapies proposed for treating peri-implantitis are based on the evidence available for the treatment of periodontitis, and are aimed at reducing the bacterial load within peri-implant pockets and decontaminating implant surfaces, and, in some cases, attempting afterward to bring about bone regeneration. The treatment of peri-implant infections comprises conservative (nonsurgical and surgical approaches. This paper reviews various treatment strategies used for the treatment of peri-implant diseases. There are many approaches suggested by various authors for the treatment of peri-implant diseases, but there is no “ideal peri-implant therapy” that has been described in the literature. There is no consensus regarding the treatment protocol as the studies conducted so far have had varying study designs, small sample sizes, and short follow-up periods.

  17. Miniscrew implant applications in contemporary orthodontics

    Hong-Po Chang

    2014-03-01

    Full Text Available The need for orthodontic treatment modalities that provide maximal anchorage control but with minimal patient compliance requirements has led to the development of implant-assisted orthodontics and dentofacial orthopedics. Skeletal anchorage with miniscrew implants has no patient compliance requirements and has been widely incorporated in orthodontic practice. Miniscrew implants are now routinely used as anchorage devices in orthodontic treatment. This review summarizes recent data regarding the interpretation of bone data (i.e., bone quantity and quality obtained by preoperative diagnostic computed tomography (CT or by cone-beam computed tomography (CBCT prior to miniscrew implant placement. Such data are essential when selecting appropriate sites for miniscrew implant placement. Bone characteristics that are indications and contraindications for treatment with miniscrew implants are discussed. Additionally, bicortical orthodontic skeletal anchorage, risks associated with miniscrew implant failure, and miniscrew implants for nonsurgical correction of occlusal cant or vertical excess are reviewed. Finally, implant stability is compared between titanium alloy and stainless steel miniscrew implants.

  18. Customizable cap implants for neurophysiological experimentation.

    Blonde, Jackson D; Roussy, Megan; Luna, Rogelio; Mahmoudian, Borna; Gulli, Roberto A; Barker, Kevin C; Lau, Jonathan C; Martinez-Trujillo, Julio C

    2018-04-22

    Several primate neurophysiology laboratories have adopted acrylic-free, custom-fit cranial implants. These implants are often comprised of titanium or plastic polymers, such as polyether ether ketone (PEEK). Titanium is favored for its mechanical strength and osseointegrative properties whereas PEEK is notable for its lightweight, machinability, and MRI compatibility. Recent titanium/PEEK implants have proven to be effective in minimizing infection and implant failure, thereby prolonging experiments and optimizing the scientific contribution of a single primate. We created novel, customizable PEEK 'cap' implants that contour to the primate's skull. The implants were created using MRI and/or CT data, SolidWorks software and CNC-machining. Three rhesus macaques were implanted with a PEEK cap implant. Head fixation and chronic recordings were successfully performed. Improvements in design and surgical technique solved issues of granulation tissue formation and headpost screw breakage. Primate cranial implants have traditionally been fastened to the skull using acrylic and anchor screws. This technique is prone to skin recession, infection, and implant failure. More recent methods have used imaging data to create custom-fit titanium/PEEK implants with radially extending feet or vertical columns. Compared to our design, these implants are more surgically invasive over time, have less force distribution, and/or do not optimize the utilizable surface area of the skull. Our PEEK cap implants served as an effective and affordable means to perform electrophysiological experimentation while reducing surgical invasiveness, providing increased strength, and optimizing useful surface area. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  19. Metallic oxide nano-clusters synthesis by ion implantation in high purity Fe10Cr alloy

    Zheng, Ce

    2015-01-01

    ODS (Oxide Dispersed Strengthened) steels, which are reinforced with metal dispersions of nano-oxides (based on Y, Ti and O elements), are promising materials for future nuclear reactors. The detailed understanding of the mechanisms involved in the precipitation of these nano-oxides would improve manufacturing and mechanical properties of these ODS steels, with a strong economic impact for their industrialization. To experimentally study these mechanisms, an analytical approach by ion implantation is used, to control various parameters of synthesis of these precipitates as the temperature and concentration. This study demonstrated the feasibility of this method and concerned the behaviour of alloys models (based on aluminium oxide) under thermal annealing. High purity Fe-10Cr alloys were implanted with Al and O ions at room temperature. Transmission electron microscopy observations showed that the nano-oxides appear in the Fe-10Cr matrix upon ion implantation at room temperature without subsequent annealing. The mobility of implanted elements is caused by the defects created during ion implantation, allowing the nucleation of these nanoparticles, of a few nm in diameter. These nanoparticles are composed of aluminium and oxygen, and also chromium. The high-resolution experiments show that their crystallographic structure is that of a non-equilibrium compound of aluminium oxide (cubic γ-Al 2 O 3 type). The heat treatment performed after implantation induces the growth of the nano-sized oxides, and a phase change that tends to balance to the equilibrium structure (hexagonal α-Al 2 O 3 type). These results on model alloys are fully applicable to industrial materials: indeed ion implantation reproduces the conditions of milling and heat treatments are at equivalent temperatures to those of thermo-mechanical treatments. A mechanism involving the precipitation of nano-oxide dispersed in ODS alloys is proposed in this manuscript based on the obtained experimental results

  20. Implantation rate effects on microstructure

    Choyke, W.J.; Spitznagel, J.A.; Wood, S.; Doyle, N.J.

    1981-01-01

    We report a detailed TEM study of rate effects in a metal (304 SS) where we dope with an insoluble atom (He) and create the displacement damage with high energy Si. The rates of doping and the rates of producing lattice damage are independently varied during dual implantation. In addition to varying the doping rates of the He the magnitude of the displacement damage prior to He implantation is also varied (beam history). We find that the beam history has virtually no effect on maximum bubble size but it has a major effect on the average cavity diameter. A weak dependence of cavity number density on helium implantation rate is found. The total dislocation density is relatively independent of the doping rate and beam history at 550 and 700 0 C, whereas the loop fraction is sensitive to beam history at these temperatures. Acicular precipitate formation is weakly dependent on doping, doping rate and more strongly dependent on doping concentration and temperature. This form of solute segregation is very sensitive to beam history. (orig.)

  1. Survival of dental implants placed in sites of previously failed implants.

    Chrcanovic, Bruno R; Kisch, Jenö; Albrektsson, Tomas; Wennerberg, Ann

    2017-11-01

    To assess the survival of dental implants placed in sites of previously failed implants and to explore the possible factors that might affect the outcome of this reimplantation procedure. Patients that had failed dental implants, which were replaced with the same implant type at the same site, were included. Descriptive statistics were used to describe the patients and implants; survival analysis was also performed. The effect of systemic, environmental, and local factors on the survival of the reoperated implants was evaluated. 175 of 10,096 implants in 98 patients were replaced by another implant at the same location (159, 14, and 2 implants at second, third, and fourth surgeries, respectively). Newly replaced implants were generally of similar diameter but of shorter length compared to the previously placed fixtures. A statistically significant greater percentage of lost implants were placed in sites with low bone quantity. There was a statistically significant difference (P = 0.032) in the survival rates between implants that were inserted for the first time (94%) and implants that replaced the ones lost (73%). There was a statistically higher failure rate of the reoperated implants for patients taking antidepressants and antithrombotic agents. Dental implants replacing failed implants had lower survival rates than the rates reported for the previous attempts of implant placement. It is suggested that a site-specific negative effect may possibly be associated with this phenomenon, as well as the intake of antidepressants and antithrombotic agents. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Influence of different implant materials on the primary stability of orthodontic mini-implants.

    Pan, Chin-Yun; Chou, Szu-Ting; Tseng, Yu-Chuan; Yang, Yi-Hsin; Wu, Chao-Yi; Lan, Ting-Hsun; Liu, Pao-Hsin; Chang, Hong-Po

    2012-12-01

    This study evaluates the influence of different implant materials on the primary stability of orthodontic mini-implants by measuring the resonance frequency. Twenty-five orthodontic mini-implants with a diameter of 2 mm were used. The first group contained stainless steel mini-implants with two different lengths (10 and 12 mm). The second group included titanium alloy mini-implants with two different lengths (10 and 12 mm) and stainless steel mini-implants 10 mm in length. The mini-implants were inserted into artificial bones with a 2-mm-thick cortical layer and 40 or 20 lb/ft(3) trabecular bone density at insertion depths of 2, 4, and 6 mm. The resonance frequency of the mini-implants in the artificial bone was detected with the Implomates(®) device. Data were analyzed by two-way analysis of variance followed by the Tukey honestly significant difference test (α = 0.05). Greater insertion depth resulted in higher resonance frequency, whereas longer mini-implants showed lower resonance frequency values. However, resonance frequency was not influenced by the implant materials titanium alloy or stainless steel. Therefore, the primary stability of a mini-implant is influenced by insertion depth and not by implant material. Insertion depth is extremely important for primary implant stability and is critical for treatment success. Copyright © 2012. Published by Elsevier B.V.

  3. Influence of different implant materials on the primary stability of orthodontic mini-implants

    Chin-Yun Pan

    2012-12-01

    Full Text Available This study evaluates the influence of different implant materials on the primary stability of orthodontic mini-implants by measuring the resonance frequency. Twenty-five orthodontic mini-implants with a diameter of 2 mm were used. The first group contained stainless steel mini-implants with two different lengths (10 and 12 mm. The second group included titanium alloy mini-implants with two different lengths (10 and 12 mm and stainless steel mini-implants 10 mm in length. The mini-implants were inserted into artificial bones with a 2-mm-thick cortical layer and 40 or 20 lb/ft3 trabecular bone density at insertion depths of 2, 4, and 6 mm. The resonance frequency of the mini-implants in the artificial bone was detected with the Implomates® device. Data were analyzed by two-way analysis of variance followed by the Tukey honestly significant difference test (α = 0.05. Greater insertion depth resulted in higher resonance frequency, whereas longer mini-implants showed lower resonance frequency values. However, resonance frequency was not influenced by the implant materials titanium alloy or stainless steel. Therefore, the primary stability of a mini-implant is influenced by insertion depth and not by implant material. Insertion depth is extremely important for primary implant stability and is critical for treatment success.

  4. Fully filamentized HTS coated conductor via striation and selective electroplating

    Kesgin, Ibrahim; Majkic, Goran [Department of Mechanical Engineering and Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States); Selvamanickam, Venkat, E-mail: selva@uh.edu [Department of Mechanical Engineering and Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States)

    2013-03-15

    Highlights: ► Fully-filamentized coated conductor with 13-fold reduction in ac losses. ► Selective electroplating for filamentization of thick copper stabilizer. ► A twofold decrease in ac loss by filamentization of copper stabilizer. ► Absence of appreciable coupling loss contribution from electroplating. -- Abstract: A simple, cost-effective method involving top-down mechanical scribing, oxidation and bottom-up electroplating has been successfully developed to fabricate fully filamentized HTS coated conductors. The copper stabilizer layer is selectively electroplated on the superconducting filaments while the striations remain copper-free due to the formation of a resistive oxide layer in between filaments by oxidation of the striated grooves at elevated temperature in oxygen atmosphere. Magnetization AC loss measurements, performed in a frequency range of 45–500 Hz at 77 K, confirmed the expected N-fold reduction in AC loss of the filamentized tapes with no significant degradation in critical current beyond that due to the material removal from the striations (N – number of filaments). A considerable reduction in coupling AC loss was observed after high temperature annealing/oxidation of the striated tapes. Furthermore, a significant reduction in eddy current loss was achieved with selective copper electroplating, as evidenced by analyzing the field and frequency dependence of magnetization AC loss, as well as by comparing the AC loss performance of striated samples to that of non-striated samples after electroplating of copper stabilizer.

  5. Fully Automated Deep Learning System for Bone Age Assessment.

    Lee, Hyunkwang; Tajmir, Shahein; Lee, Jenny; Zissen, Maurice; Yeshiwas, Bethel Ayele; Alkasab, Tarik K; Choy, Garry; Do, Synho

    2017-08-01

    Skeletal maturity progresses through discrete phases, a fact that is used routinely in pediatrics where bone age assessments (BAAs) are compared to chronological age in the evaluation of endocrine and metabolic disorders. While central to many disease evaluations, little has changed to improve the tedious process since its introduction in 1950. In this study, we propose a fully automated deep learning pipeline to segment a region of interest, standardize and preprocess input radiographs, and perform BAA. Our models use an ImageNet pretrained, fine-tuned convolutional neural network (CNN) to achieve 57.32 and 61.40% accuracies for the female and male cohorts on our held-out test images. Female test radiographs were assigned a BAA within 1 year 90.39% and within 2 years 98.11% of the time. Male test radiographs were assigned 94.18% within 1 year and 99.00% within 2 years. Using the input occlusion method, attention maps were created which reveal what features the trained model uses to perform BAA. These correspond to what human experts look at when manually performing BAA. Finally, the fully automated BAA system was deployed in the clinical environment as a decision supporting system for more accurate and efficient BAAs at much faster interpretation time (<2 s) than the conventional method.

  6. Fully kinetic particle simulations of high pressure streamer propagation

    Rose, David; Welch, Dale; Thoma, Carsten; Clark, Robert

    2012-10-01

    Streamer and leader formation in high pressure devices is a dynamic process involving a hierarchy of physical phenomena. These include elastic and inelastic particle collisions in the gas, radiation generation, transport and absorption, and electrode interactions. We have performed 2D and 3D fully EM implicit particle-in-cell simulation model of gas breakdown leading to streamer formation under DC and RF fields. The model uses a Monte Carlo treatment for all particle interactions and includes discrete photon generation, transport, and absorption for ultra-violet and soft x-ray radiation. Central to the realization of this fully kinetic particle treatment is an algorithm [D. R. Welch, et al., J. Comp. Phys. 227, 143 (2007)] that manages the total particle count by species while preserving the local momentum distribution functions and conserving charge. These models are being applied to the analysis of high-pressure gas switches [D. V. Rose, et al., Phys. Plasmas 18, 093501 (2011)] and gas-filled RF accelerator cavities [D. V. Rose, et al. Proc. IPAC12, to appear].

  7. Development of Low Energy Gap and Fully Regioregular Polythienylenevinylene Derivative

    Tanya M. S. David

    2014-01-01

    Full Text Available Low energy gap and fully regioregular conjugated polymers find its wide use in solar energy conversion applications. This paper will first briefly review this type of polymers and also report synthesis and characterization of a specific example new polymer, a low energy gap, fully regioregular, terminal functionalized, and processable conjugated polymer poly-(3-dodecyloxy-2,5-thienylene vinylene or PDDTV. The polymer exhibited an optical energy gap of 1.46 eV based on the UV-vis-NIR absorption spectrum. The electrochemically measured highest occupied molecular orbital (HOMO level is −4.79 eV, resulting in the lowest unoccupied molecular orbital (LUMO level of −3.33 eV based on optical energy gap. The polymer was synthesized via Horner-Emmons condensation and is fairly soluble in common organic solvents such as tetrahydrofuran and chloroform with gentle heating. DSC showed two endothermic peaks at 67°C and 227°C that can be attributed to transitions between crystalline and liquid states. The polymer is thermally stable up to about 300°C. This polymer appears very promising for cost-effective solar cell applications.

  8. Fully vs. Sequentially Coupled Loads Analysis of Offshore Wind Turbines

    Damiani, Rick; Wendt, Fabian; Musial, Walter; Finucane, Z.; Hulliger, L.; Chilka, S.; Dolan, D.; Cushing, J.; O' Connell, D.; Falk, S.

    2017-06-19

    The design and analysis methods for offshore wind turbines must consider the aerodynamic and hydrodynamic loads and response of the entire system (turbine, tower, substructure, and foundation) coupled to the turbine control system dynamics. Whereas a fully coupled (turbine and support structure) modeling approach is more rigorous, intellectual property concerns can preclude this approach. In fact, turbine control system algorithms and turbine properties are strictly guarded and often not shared. In many cases, a partially coupled analysis using separate tools and an exchange of reduced sets of data via sequential coupling may be necessary. In the sequentially coupled approach, the turbine and substructure designers will independently determine and exchange an abridged model of their respective subsystems to be used in their partners' dynamic simulations. Although the ability to achieve design optimization is sacrificed to some degree with a sequentially coupled analysis method, the central question here is whether this approach can deliver the required safety and how the differences in the results from the fully coupled method could affect the design. This work summarizes the scope and preliminary results of a study conducted for the Bureau of Safety and Environmental Enforcement aimed at quantifying differences between these approaches through aero-hydro-servo-elastic simulations of two offshore wind turbines on a monopile and jacket substructure.

  9. A Fully Automated High-Throughput Zebrafish Behavioral Ototoxicity Assay.

    Todd, Douglas W; Philip, Rohit C; Niihori, Maki; Ringle, Ryan A; Coyle, Kelsey R; Zehri, Sobia F; Zabala, Leanne; Mudery, Jordan A; Francis, Ross H; Rodriguez, Jeffrey J; Jacob, Abraham

    2017-08-01

    Zebrafish animal models lend themselves to behavioral assays that can facilitate rapid screening of ototoxic, otoprotective, and otoregenerative drugs. Structurally similar to human inner ear hair cells, the mechanosensory hair cells on their lateral line allow the zebrafish to sense water flow and orient head-to-current in a behavior called rheotaxis. This rheotaxis behavior deteriorates in a dose-dependent manner with increased exposure to the ototoxin cisplatin, thereby establishing itself as an excellent biomarker for anatomic damage to lateral line hair cells. Building on work by our group and others, we have built a new, fully automated high-throughput behavioral assay system that uses automated image analysis techniques to quantify rheotaxis behavior. This novel system consists of a custom-designed swimming apparatus and imaging system consisting of network-controlled Raspberry Pi microcomputers capturing infrared video. Automated analysis techniques detect individual zebrafish, compute their orientation, and quantify the rheotaxis behavior of a zebrafish test population, producing a powerful, high-throughput behavioral assay. Using our fully automated biological assay to test a standardized ototoxic dose of cisplatin against varying doses of compounds that protect or regenerate hair cells may facilitate rapid translation of candidate drugs into preclinical mammalian models of hearing loss.

  10. Fully resolved simulations of expansion waves propagating into particle beds

    Marjanovic, Goran; Hackl, Jason; Annamalai, Subramanian; Jackson, Thomas; Balachandar, S.

    2017-11-01

    There is a tremendous amount of research that has been done on compression waves and shock waves moving over particles but very little concerning expansion waves. Using 3-D direct numerical simulations, this study will explore expansion waves propagating into fully resolved particle beds of varying volume fractions and geometric arrangements. The objectives of these simulations are as follows: 1) To fully resolve all (1-way coupled) forces on the particles in a time varying flow and 2) to verify state-of-the-art drag models for such complex flows. We will explore a range of volume fractions, from very low ones that are similar to single particle flows, to higher ones where nozzling effects are observed between neighboring particles. Further, we will explore two geometric arrangements: body centered cubic and face centered cubic. We will quantify the effects that volume fraction and geometric arrangement plays on the drag forces and flow fields experienced by the particles. These results will then be compared to theoretical predictions from a model based on the generalized Faxen's theorem. This work was supported in part by the U.S. Department of Energy under the Predictive Science Academic Alliance Program, under Contract No. DE-NA0002378.

  11. Fully filamentized HTS coated conductor via striation and selective electroplating

    Kesgin, Ibrahim; Majkic, Goran; Selvamanickam, Venkat

    2013-01-01

    Highlights: ► Fully-filamentized coated conductor with 13-fold reduction in ac losses. ► Selective electroplating for filamentization of thick copper stabilizer. ► A twofold decrease in ac loss by filamentization of copper stabilizer. ► Absence of appreciable coupling loss contribution from electroplating. -- Abstract: A simple, cost-effective method involving top-down mechanical scribing, oxidation and bottom-up electroplating has been successfully developed to fabricate fully filamentized HTS coated conductors. The copper stabilizer layer is selectively electroplated on the superconducting filaments while the striations remain copper-free due to the formation of a resistive oxide layer in between filaments by oxidation of the striated grooves at elevated temperature in oxygen atmosphere. Magnetization AC loss measurements, performed in a frequency range of 45–500 Hz at 77 K, confirmed the expected N-fold reduction in AC loss of the filamentized tapes with no significant degradation in critical current beyond that due to the material removal from the striations (N – number of filaments). A considerable reduction in coupling AC loss was observed after high temperature annealing/oxidation of the striated tapes. Furthermore, a significant reduction in eddy current loss was achieved with selective copper electroplating, as evidenced by analyzing the field and frequency dependence of magnetization AC loss, as well as by comparing the AC loss performance of striated samples to that of non-striated samples after electroplating of copper stabilizer

  12. Large fully retractable telescope enclosures still closable in strong wind

    Bettonvil, Felix C. M.; Hammerschlag, Robert H.; Jägers, Aswin P. L.; Sliepen, Guus

    2008-07-01

    Two prototypes of fully retractable enclosures with diameters of 7 and 9 m have been built for the high-resolution solar telescopes DOT (Dutch Open Telescope) and GREGOR, both located at the Canary Islands. These enclosures protect the instruments for bad weather and are fully open when the telescopes are in operation. The telescopes and enclosures also operate in hard wind. The prototypes are based on tensioned membrane between movable but stiff bows, which fold together to a ring when opened. The height of the ring is small. The prototypes already survived several storms, with often snow and ice, without any damage, including hurricane Delta with wind speeds up to 68 m/s. The enclosures can still be closed and opened with wind speeds of 20 m/s without any problems or restrictions. The DOT successfully demonstrated the open, wind-flushing concept for astronomical telescopes. It is now widely recognized that also large future telescopes benefit from wind-flushing and retractable enclosures. These telescopes require enclosures with diameters of 30 m until roughly 100 m, the largest sizes for the ELTs (Extreme Large Telescopes), which will be built in the near future. We discuss developments and required technology for the realization of these large sizes.

  13. Fully Automated Lipid Pool Detection Using Near Infrared Spectroscopy

    Elżbieta Pociask

    2016-01-01

    Full Text Available Background. Detecting and identifying vulnerable plaque, which is prone to rupture, is still a challenge for cardiologist. Such lipid core-containing plaque is still not identifiable by everyday angiography, thus triggering the need to develop a new tool where NIRS-IVUS can visualize plaque characterization in terms of its chemical and morphologic characteristic. The new tool can lead to the development of new methods of interpreting the newly obtained data. In this study, the algorithm to fully automated lipid pool detection on NIRS images is proposed. Method. Designed algorithm is divided into four stages: preprocessing (image enhancement, segmentation of artifacts, detection of lipid areas, and calculation of Lipid Core Burden Index. Results. A total of 31 NIRS chemograms were analyzed by two methods. The metrics, total LCBI, maximal LCBI in 4 mm blocks, and maximal LCBI in 2 mm blocks, were calculated to compare presented algorithm with commercial available system. Both intraclass correlation (ICC and Bland-Altman plots showed good agreement and correlation between used methods. Conclusions. Proposed algorithm is fully automated lipid pool detection on near infrared spectroscopy images. It is a tool developed for offline data analysis, which could be easily augmented for newer functions and projects.

  14. Fully Premixed Low Emission, High Pressure Multi-Fuel Burner

    Nguyen, Quang-Viet (Inventor)

    2012-01-01

    A low-emissions high-pressure multi-fuel burner includes a fuel inlet, for receiving a fuel, an oxidizer inlet, for receiving an oxidizer gas, an injector plate, having a plurality of nozzles that are aligned with premix face of the injector plate, the plurality of nozzles in communication with the fuel and oxidizer inlets and each nozzle providing flow for one of the fuel and the oxidizer gas and an impingement-cooled face, parallel to the premix face of the injector plate and forming a micro-premix chamber between the impingement-cooled face and the in injector face. The fuel and the oxidizer gas are mixed in the micro-premix chamber through impingement-enhanced mixing of flows of the fuel and the oxidizer gas. The burner can be used for low-emissions fuel-lean fully-premixed, or fuel-rich fully-premixed hydrogen-air combustion, or for combustion with other gases such as methane or other hydrocarbons, or even liquid fuels.

  15. Selective laser sintering of calcium phosphate materials for orthopedic implants

    Lee, Goonhee

    control of micro and macro pore structure, to maximize bone healing and provide sufficient mechanical strength. It also permits the complete removal of the polymeric binders that are resided in the SLS process. In collaboration with the University of Texas Health Science Center at San Antonio and BioMedical Enterprises, Inc., porous implants based on anatomical geometry have been successfully implanted in rabbits and dogs. These histologic animal studies reveal excellent biocompatibility and show its great potential for commercial custom-fit implant manufacture. The second research effort involves fabrication of fully dense bone for application in dental restoration and load-bearing orthopedic functions. Calcium phosphate glass melts, proven to be biocompatible in the first effort, were cast into carbon molds. Processes were developed for preparing the molds. These carbon molds of anatomic shape can be prepared from either Computer Numerical Control (CNC) milling of slab stock or SLS processing of thermoset-coated graphite powder. The CNC milling method provides accurate dimension of the molds in a short period of time, however, the capable geometries are limited; generally two pieces of molds are required for complex shapes. The SLS method provides very complex shape green molds. However, they need to go through pyrolysis of thermoset binder to provide the high temperature capability reached at calcium phosphate melt temperatures (1100°C) and noticeable shrinkage was observed during pyrolysis. The cast glass was annealed to develop polycrystalline calcium phosphate. This process also exhibits great potential.

  16. Methods to measure stability of dental implants

    Shruti Digholkar

    2014-01-01

    Full Text Available Dental implant treatment is an excellent option for prosthetic restoration that is associated with high success rates. Implant stability is essential for a good outcome. The clinical assessment of osseointegration is based on mechanical stability rather than histological criteria, considering primary stability (absence of mobility in bone bed after implant insertion and secondary stability (bone formation and remodeling at implant-bone interface. However, due to the invasive nature of the histological methods various other methods have been proposed: Radiographs, the surgeon′s perception, Insertion torque (cutting torque analysis, seating torque, reverse torque testing, percussion testing, impact hammer method, pulsed oscillation waveform, implant mobility checker, Periotest, resonance frequency analysis. This review focuses on the methods currently available for the evaluation of implant stability.

  17. Electrochemical properties of ion implanted silicon

    Pham minh Tan.

    1979-11-01

    The electrochemical behaviour of ion implanted silicon in contact with hydrofluoric acid solution was investigated. It was shown that the implanted layer on silicon changes profoundly its electrochemical properties (photopotential, interface impedance, rest potential, corrosion, current-potential behaviour, anodic dissolution of silicon, redox reaction). These changes depend strongly on the implantation parameters such as ion dose, ion energy, thermal treatment and ion mass and are weakly dependent on the chemical nature of the implantation ion. The experimental results were evaluated and interpreted in terms of the semiconductor electrochemical concepts taking into account the interaction of energetic ions with the solid surface. The observed effects are thus attributed to the implantation induced damage of silicon lattice and can be used for profiling of the implanted layer and the electrochemical treatment of the silicon surface. (author)

  18. Early Loaded Single Implant Reinforced Mandibular Overdenture

    K. Nischal

    2016-01-01

    Full Text Available Rehabilitating atrophied mandible with two-implant supported denture is a common treatment modality for implant retained removable overdenture in mandible. This paper aims to design a treatment modality where single implant reinforced overdenture is fabricated for a severely atrophied mandibular ridge with early loading protocol. Results of studies have shown that a single implant mandibular overdenture significantly increases the satisfaction and quality of life of patients with edentulism. Midline fracture of the prosthesis is the most common complication related to single implant and two-implant retained mandibular overdentures. To manage such complication, a thin metal mesh is used to reinforce the overdenture and also to make the prostheses lighter and cost effective as compared to conventional cast metal framework.

  19. Implant supported overdentures--the Copenhagen experience

    Gotfredsen, K

    1997-01-01

    OBJECTIVES: To evaluate the functional and biological effect of implant-supported overdenture treatment in the lower jaw. METHODS AND MATERIALS: Thirty-two patients were consecutively treated with Astra Tech implants in the lower jaw for retaining overdentures. All implants had a diameter of 3.5 mm...... and all but two of the implants were longer than 10 mm. For the implant supported overdentures two methods of attachment were used, a bar or a ball. RESULTS: One of 69 fixtures was lost during the 4-5 year observation period. The mean bone loss for all fixtures was less than 0.2 mm per year. Complications...... quality and quantity is sufficient, two implants can support an overdenture in the lower jaw, providing prosthesis which functions well....

  20. [Fusion implants of carbon fiber reinforced plastic].

    Früh, H J; Liebetrau, A; Bertagnoli, R

    2002-05-01

    Carbon fiber reinforced plastics (CFRP) are used in the medical field when high mechanical strength, innovative design, and radiolucency (see spinal fusion implants) are needed. During the manufacturing process of the material CFRP carbon fibers are embedded into a resin matrix. This resin material could be thermoset (e.g., epoxy resin EPN/DDS) or thermoplastic (e.g., PEAK). CFRP is biocompatible, radiolucent, and has higher mechanical capabilities compared to other implant materials. This publication demonstrates the manufacturing process of fusion implants made of a thermoset matrix system using a fiber winding process. The material has been used clinically since 1994 for fusion implants of the cervical and lumbar spine. The results of the fusion systems CORNERSTONE-SR C (cervical) and UNION (lumbar) showed no implant-related complications. New implant systems made of this CFRP material are under investigation and are presented.

  1. A case of peri-implantitis and osteoradionecrosis arising around dental implants placed before radiation therapy

    Teramoto, Yuji; Kurita, Hiroshi; Kamata, Takahiro; Aizawa, Hitoshi; Yoshimura, Nobuhiko; Nishimaki, Humihiro; Takamizawa, Kazunobu

    2016-01-01

    A little is known about the effect of radiotherapy on the dental implants that have previously been osseointegrated and charged. Here, we reported a case of osteoradionecrosis which arose around dental implants placed before radiation therapy.

  2. Long time follow up of implant therapy and treatment of peri-implantitis.

    Roos-Jansåker, Ann-Marie

    2007-01-01

    Dental implants have become an often used alternative to replace missing teeth, resulting in an increasing percentage of the adult population with implant supported prosthesis. Although favourable long-term results of implant therapy have been reported, infections occur. Until recently few reports included data on peri-implant infections, possibly underestimating this complication of implant treatment. It is possible that some infections around implants develop slowly and that with time peri-implantitis will be a common complication to implant therapy as an increasing number of patients have had their implants for a long time (>10 years). Data on treatment of peri-implant lesions are scarce leaving the clinician with limited guidance regarding choice of treatment. The aim of this thesis was to study the frequency of implant loss and presence of peri-implant lesions in a group of patients supplied with Brånemark implants 9-14 years ago, and to relate these events to patient and site specific characteristics. Moreover three surgical treatment modalities for peri-implantitis were evaluated. The thesis is based on six studies; Studies I-III included 218 patients and 1057 implants followed for 9-14 years evaluating prevalence of, and factors related to implant loss (Paper I) and prevalence of peri-implant infections and related factors (Paper I-III). Study IV is a review describing different treatment modalities of peri-implant infections. Study V is a prospective cohort study involving 36 patients and 65 implants, evaluating the use of a bone substitute with or without the use of a resorbable membrane. Study VI is a case series with 12 patients and 16 implants, evaluating a bone substitute in combination with a resorbable membrane and submerged healing. This thesis demonstrated that: After 9-14 years the survival rates of dental implants are high (95.7%). Implant loss seems to cluster within patients and are related to periodontitis evidenced as bone loss on

  3. Infective endocarditis and risk of death after cardiac implantable electronic device implantation

    Özcan, Cengiz; Raunsø, Jakob; Lamberts, Morten

    2017-01-01

    AIMS: To determine the incidence, risk factors, and mortality of infective endocarditis (IE) following implantation of a first-time, permanent, cardiac implantable electronic device (CIED). METHODS AND RESULTS: From Danish nationwide administrative registers (beginning in 1996), we identified all...

  4. Strain driven fast osseointegration of implants

    Wiesmann Hans-Peter

    2005-09-01

    Full Text Available Abstract Background Although the bone's capability of dental implant osseointegration has clinically been utilised as early as in the Gallo-Roman population, the specific mechanisms for the emergence and maintenance of peri-implant bone under functional load have not been identified. Here we show that under immediate loading of specially designed dental implants with masticatory loads, osseointegration is rapidly achieved. Methods We examined the bone reaction around non- and immediately loaded dental implants inserted in the mandible of mature minipigs during the presently assumed time for osseointegration. We used threaded conical titanium implants containing a titanium2+ oxide surface, allowing direct bone contact after insertion. The external geometry was designed according to finite element analysis: the calculation showed that physiological amplitudes of strain (500–3,000 ustrain generated through mastication were homogenously distributed in peri-implant bone. The strain-energy density (SED rate under assessment of a 1 Hz loading cycle was 150 Jm-3 s-1, peak dislocations were lower then nm. Results Bone was in direct contact to the implant surface (bone/implant contact rate 90% from day one of implant insertion, as quantified by undecalcified histological sections. This effect was substantiated by ultrastructural analysis of intimate osteoblast attachment and mature collagen mineralisation at the titanium surface. We detected no loss in the intimate bone/implant bond during the experimental period of either control or experimental animals, indicating that immediate load had no adverse effect on bone structure in peri-implant bone. Conclusion In terms of clinical relevance, the load related bone reaction at the implant interface may in combination with substrate effects be responsible for an immediate osseointegration state.

  5. Characterization of diamond amorphized by ion implantation

    Allen, W.R.; Lee, E.H.

    1992-01-01

    Single crystal diamond has been implanted at 1 MeV with 2 x 10 20 Ar/m 2 . Rutherford backscattering spectrometry in a channeled geometry revealed a broad amorphized region underlying a thin, partially crystalline layer. Raman spectroscopy disclosed modifications in the bonding characteristic of the appearance of non-diamond carbon. The complementary nature of the two analysis techniques is demonstrated. The Knoop hardness of the implanted diamond was reduced by implantation

  6. Modification of metallic corrosion by ion implantation

    Clayton, C.R.

    1981-01-01

    This review will consider some of the properties of surface alloys, formed by ion implantation, which are effective in modifying corrosion behaviour. Examples will be given of the modification of the corrosion behaviour of pure metals, steels and other engineering alloys, resulting from implantation with metals and metalloids. Emphasis will be given to the modification of anodic processes produced by ion implantation since a review will be given elsewhere in the proceedings concerning the modification of cathodic processes. (orig.)

  7. Relation between bruxism and dental implants

    TORCATO,Leonardo Bueno; ZUIM,Paulo Renato Junqueira; BRANDINI,Daniela Atili; FALCÓN-ANTENUCCI,Rosse Mary

    2014-01-01

    OBJECTIVE: The aim of this study was to gather information and discuss the predictability of implant-supported prostheses in patients with bruxism by performing a literature review.METHODS: In order to select the studies included in this review, a detailed search was performed in PubMed and Medlinedatabases, using the following key words: bruxism, dental implants, implant supported prosthesis, and dental restoration failure. Items that were included are: case reports, randomized controlled tr...

  8. CEMS of Sb+ implanted stainless steels

    Roy-Poulsen, H.; Johnson, E.; Johansen, A.; Sarholt-Kristensen, L.; Hayashi, H.

    1986-01-01

    Martensitic transformations have been analyzed in a series of antimony implanted austenitic stainless steels using CEMS. The implanted samples contain about 70 vol% martensite, which is considerably more than can be formed conventionally by plastic deformation of cooling below the martensite start temperature. CEM spectra from implantation induced martensite and from martensite formed in conventional processes are virtually identical. In both cases the hyperfine field is ∼ 25T. (Auth.)

  9. CEMS of Sb+ implanted stainless steels

    Roy-Poulsen, H.; Copenhagen Univ.; Johnson, E.; Johansen, A.; Sarholt-Kristensen, L.; Hayashi, H.

    1985-01-01

    Martensitic transformations have been analyzed in a series of antimony implanted austenitic stainless steels using CEMS. The implanted samples contain about 70 vol% martensite, which is considerably more than can be formed conventionally by plastic deformation or cooling below the martensite start temperature. CEM spectra from implantation induced martensite and from martensite formed in conventional processes are virtually identical. In both cases the hyperfine field is ∝25 T. (orig.)

  10. Cochlear implant revision surgeries in children.

    Amaral, Maria Stella Arantes do; Reis, Ana Cláudia Mirândola B; Massuda, Eduardo T; Hyppolito, Miguel Angelo

    2018-02-16

    The surgery during which the cochlear implant internal device is implanted is not entirely free of risks and may produce problems that will require revision surgeries. To verify the indications for cochlear implantation revision surgery for the cochlear implant internal device, its effectiveness and its correlation with certain variables related to language and hearing. A retrospective study of patients under 18 years submitted to cochlear implant Surgery from 2004 to 2015 in a public hospital in Brazil. Data collected were: age at the time of implantation, gender, etiology of the hearing loss, audiological and oral language characteristics of each patient before and after Cochlear Implant surgery and any need for surgical revision and the reason for it. Two hundred and sixty-five surgeries were performed in 236 patients. Eight patients received a bilateral cochlear implant and 10 patients required revision surgery. Thirty-two surgeries were necessary for these 10 children (1 bilateral cochlear implant), of which 21 were revision surgeries. In 2 children, cochlear implant removal was necessary, without reimplantation, one with cochlear malformation due to incomplete partition type I and another due to trauma. With respect to the cause for revision surgery, of the 8 children who were successfully reimplanted, four had cochlear calcification following meningitis, one followed trauma, one exhibited a facial nerve malformation, one experienced a failure of the cochlear implant internal device and one revision surgery was necessary because the electrode was twisted. The incidence of the cochlear implant revision surgery was 4.23%. The period following the revision surgeries revealed an improvement in the subject's hearing and language performance, indicating that these surgeries are valid in most cases. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  11. Fully integrated CMOS pixel detector for high energy particles

    Vanstraelen, G.; Debusschere, I.; Claeys, C.; Declerck, G.

    1989-01-01

    A novel type of position and energy sensitive, monolithic pixel array with integrated readout electronics is proposed. Special features of the design are a reduction of the number of output channels and of the amount of output data, and the use of transistors on the high resistivity silicon. The number of output channels for the detector array is reduced by handling in parallel a number of pixels, chosen as a function of the time resolution required for the system, and by the use of an address decoder. A further reduction of data is achieved by reading out only those pixels which have been activated. The pixel detector circuit will be realized in a 3 μm p-well CMOS process, which is optimized for the full integration of readout electronics and detector diodes on high resistivity Si. A retrograde well is formed by means of a high energy implantation, followed by the appropriate temperature steps. The optimization of the well shape takes into account the high substrate bias applied during the detector operation. The design is largely based on the use of MOS transistors on the high resistivity silicon itself. These have proven to perform as well as transistors on standard doped substrate. The basic building elements as well as the design strategy of the integrated pixel detector are presented in detail. (orig.)

  12. One-stage explant-implant procedure of exposed porous orbital implants

    Toft, Peter B; Rasmussen, Marie L Roed; Prause, Jan Ulrik

    2011-01-01

    Purpose:  To investigate the risks of implant exposure after a combined explant-implant procedure in patients with an exposed porous orbital implant. Methods:  Twenty-four consecutive patients who had a combined explant-implant procedure of an exposed hydroxyapatite (21) or porous polyethylene (3...... at the same procedure in sockets without profound signs of infection. The procedure carries a possible risk of poor motility....

  13. Systemic alendronate treatment improves fixation of press-fit implants: a canine study using nonloaded implants

    Jensen, Thomas B; Bechtold, Joan E; Chen, Xinqian

    2007-01-01

    of alendronate treatment. Bone ongrowth (bone in contact with implant surface) was estimated using the linear intercept technique and shear strength was calculated as the slope on a load-displacement curve. For the press fit implants, alendronate treatment significantly increased bone ongrowth from 24% to 29...... early implant stability is an important predictor of longevity, systemic alendronate treatment could be an important clinical tool to positively influence the early stages of implant incorporation. Udgivelsesdato: 2007-Jun...

  14. Neural Implants, Packaging for Biocompatible Implants, and Improving Fabricated Capacitors

    Agger, Elizabeth Rose

    We have completed the circuit design and packaging procedure for an NIH-funded neural implant, called a MOTE (Microscale Optoelectronically Transduced Electrode). Neural recording implants for mice have greatly advanced neuroscience, but they are often damaging and limited in their recording location. This project will result in free-floating implants that cause less damage, provide rapid electronic recording, and increase range of recording across the cortex. A low-power silicon IC containing amplification and digitization sub-circuits is powered by a dual-function gallium arsenide photovoltaic and LED. Through thin film deposition, photolithography, and chemical and physical etching, the Molnar Group and the McEuen Group (Applied and Engineering Physics department) will package the IC and LED into a biocompatible implant approximately 100microm3. The IC and LED are complete and we have begun refining this packaging procedure in the Cornell NanoScale Science & Technology Facility. ICs with 3D time-resolved imaging capabilities can image microorganisms and other biological samples given proper packaging. A portable, flat, easily manufactured package would enable scientists to place biological samples on slides directly above the Molnar group's imaging chip. We have developed a packaging procedure using laser cutting, photolithography, epoxies, and metal deposition. Using a flip-chip method, we verified the process by aligning and adhering a sample chip to a holder wafer. In the CNF, we have worked on a long-term metal-insulator-metal (MIM) capacitor characterization project. Former Fellow and continuing CNF user Kwame Amponsah developed the original procedure for the capacitor fabrication, and another former fellow, Jonilyn Longenecker, revised the procedure and began the arduous process of characterization. MIM caps are useful to clean room users as testing devices to verify electronic characteristics of their active circuitry. This project's objective is to

  15. Erbium-implanted silica colloids with 80% luminescence quantum efficiency

    Slooff, L. H.; de Dood, M. J. A.; van Blaaderen, A.; Polman, A.

    2000-06-01

    Silica colloids with a diameter of 240-360 nm, grown by wet chemical synthesis using ethanol, ammonia, water, and tetraethoxysilane, were implanted with 350 keV Er ions, to peak concentrations of 0.2-1.1 at. % and put onto a silicon or glass substrate. After annealing at 700-900 °C the colloids show clear room-temperature photoluminescence at 1.53 μm, with lifetimes as high as 17 ms. By comparing data of different Er concentrations, the purely radiative lifetime is estimated to be 20-22 ms, indicating a high quantum efficiency of about 80%. This high quantum efficiency indicates that, after annealing, the silica colloids are almost free of OH impurities. Spinning a layer of polymethylmethacrylate over the silica spheres results in an optically transparent nanocomposite layer, that can be used as a planar optical waveguide amplifier at 1.5 μm that is fully compatible with polymer technology.

  16. Feasibility of fully ceramic microencapsulated (FCM) replacement fuel assembly for OPR-1000 core fully loaded with FCM fuel assemblies

    Lee, W.J.; Lee, K.H.; Kwon, H.; Chun, J.H.; Kim, Y.M. [Korea Atomic Energy Research Inst., Daejeon (Korea, Republic of); Venneri, F. [Ultra Safe Nuclear Corp., Los Alamos, NM (United States)

    2014-07-01

    The feasibility of replacing conventional UO{sub 2} fuel assemblies (FAs) of light water reactors with accident-tolerant fully ceramic microencapsulated (FCM) FAs has been explored referencing OPR-1000, 1000MW{sub e} PWR. An optimum FCM FA design, 16x16 FCM FA with Silicon Carbide-coated Zircaloy cladding, was selected based on core-level scoping analysis for five FCM FA design candidates screened from FA-level study. For the selected FCM FA design, detailed core following analysis from initial to equilibrium cores, initially fully loaded with the FCM FAs, was carried out to quantify core physics parameters. Using these parameters, the core thermal-hydraulics and coated fuel particle performance of the FCM core was assessed, and the safety margin and accident-tolerance of the FCM core was evaluated for limiting design- and beyond design-basis-accidents. From the study, it has been demonstrated that the FCM fuel is a viable option in replacing the OPR-1000 core with enhanced safety and accident tolerance while maintaining the core neutronics, thermal-hydraulics and mechanical compatibility. (author)

  17. Limit load and fully plastic stress analysis for circular notched plates and bars using fully plastic analysis

    Oh, Chang Kyun; Myung, Man Sik; Kim, Yun Jae; Park, Jin Moo

    2005-01-01

    For the last four decades, tension test of notched bars has been performed to investigate the effect of stress triaxiality on ductile fracture. To quantify the effect of the notch radius on stress triaxiality, the Bridgman equation is typically used. However, recent works based on detailed finite element analysis have shown that the Bridgman equation is not correct, possibly due to his assumption that strain is constant in the necked ligament. Up to present, no systematic work has been performed on fully plastic stress fields for notched bars in tension. This paper presents fully plastic results for tension of notched bars and plates in plane strain, via finite element limit analysis. The notch radius is systematically varied, covering both un-cracked and cracked cases. Comparison of plastic limit loads with existing solutions shows that existing solutions are accurate for notched plates, but not for notched bars. Accordingly new limit load solutions are given for notched bars. Variations of stress triaxiality with the notch radius and depth are also given, which again indicates that the Bridgman solution for notched bars is not correct and inaccuracy depends on the notch radius and depth

  18. Trends in prosthetic biomaterials in implant dentistry

    Saranjit Singh Bhasin

    2015-01-01

    Full Text Available The most important criterion for the success of dental implants is the selection of a suitable implant biomaterial. To improve the biologic performance of an implant, it is necessary to select a material that does not elicit any negative biological response and at the same time maintains adequate function. It is mandatory for a dentist to have a comprehensive knowledge of various biomaterials used for dental implants. The material of choice for fabrication of the dental implant till date is titanium. With the advancements in the field of implants, zirconia seems to be propitious in the future. However, more advanced in vitro and in vivo studies are required before reaching any such conclusion. To increase the success of zirconia implants, care should be taken to reduce the incidence of mechanical failures. Such failures can be taken care of by having a thorough technical knowledge of implant designing and manufacturing defects. This article attempts to compare the advantages and disadvantages of various dental implant biomaterials. Focus is placed on the recent advances in this field with the recently introduced zirconia and its comparison to conventional titanium.

  19. He implantation induced nanovoids in crystalline Si

    Kilpelaeinen, S.; Kuitunen, K.; Slotte, J.; Tuomisto, F.; Bruno, E.; Mirabella, S.; Priolo, F.

    2009-01-01

    Positron annihilation spectroscopy (PAS) in Doppler broadening mode was used to study the vacancy profile of crystalline Si after He and B implantation and subsequent annealing. In the He-implanted samples two different void layers were observed, one consisting of large voids at the projected range of He and another containing 'nanovoids' slightly larger than divacancies at roughly halfway between R p of He and the surface. The nanovoid layer was shown to be absent from samples co-implanted with B, implying that interstitials created during B implantation get trapped in the nanovoids and fill them, thus hindering interstitial-mediated B diffusion.

  20. Ion implantation of boron in germanium

    Jones, K.S.

    1985-05-01

    Ion implantation of 11 B + into room temperature Ge samples leads to a p-type layer prior to any post implant annealing steps. Variable temperature Hall measurements and deep level transient spectroscopy experiments indicate that room temperature implantation of 11 B + into Ge results in 100% of the boron ions being electrically active as shallow acceptor, over the entire dose range (5 x 10 11 /cm 2 to 1 x 10 14 /cm 2 ) and energy range (25 keV to 100 keV) investigated, without any post implant annealing. The concentration of damage related acceptor centers is only 10% of the boron related, shallow acceptor center concentration for low energy implants (25 keV), but becomes dominant at high energies (100 keV) and low doses ( 12 /cm 2 ). Three damage related hole traps are produced by ion implantation of 11 B + . Two of these hole traps have also been observed in γ-irradiated Ge and may be oxygen-vacancy related defects, while the third trap may be divacancy related. All three traps anneal out at low temperatures ( 0 C). Boron, from room temperature implantation of BF 2 + into Ge, is not substitutionally active prior to a post implant annealing step of 250 0 C for 30 minutes. After annealing additional shallow acceptors are observed in BF 2 + implanted samples which may be due to fluorine or flourine related complexes which are electrically active