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The purpose of the paper is to study effect of the implantation of oxygen and helium ions on the corrosion performance of the AISI3l6L stainless steel. It presents useful new results which allows one to draw conclusions as to the suitability of the helium and oxygen ion implanted AISI 316L stainless steel for biomedical use in the body.

The implantation of oxygen and helium ions was done on AISI 316L SS at an energy level of 100 keV at a dose of 1×10¹⁷ ions/cm², at room temperature. In order to simulate the natural tissue environment, an electrochemical test using cyclic polarization was done in a 0.9 percent sodium chloride solution at a pH value of 6.3 at 37°C. This was carried out on both the virgin and implanted AISI 316L stainless steel for the purpose of comparing performance. In addition to this, the hardness of the virgin and implanted samples was also studied using Vickers microhardness tester with varying loads. Besides, the surface morphologies of the implanted samples and the corroded samples were studied with XRD and SEM.

From the study the following findings are made. First, the XRD and SEM results were found to be in accordance with the corrosion test results. Second, the general corrosion behavior showed a significant improvement in the case of both helium implanted (icorr=0.0689 mA/cm²) and oxygen implanted (icorr=1.104 mA/cm²), when compared to the virgin AISI 316L SS (icorr=1.2187 mA/cm²). The pitting corrosion showed a significant improvement for helium implanted (Epit=230 mV) when compared to virgin material (Epit=92 mV). The oxygen implanted has not shown any improvement (Epit=92 mV). The surface hardness is found to be 1202 HV for helium implanted and 1020 HV for oxygen implanted, while it is found to be 195 HV for the virgin material. The hardness of the helium and oxygen implanted samples is found to be increased by about 600 percent and 500 percent, respectively, when compared to the virgin samples. Helium implanted samples show better performance in terms of corrosion resistance and hardness when compared to those of the oxygen implanted samples.

Although a number of authors have conducted many research on AISI 316L stainless steel, this work has original experimental results in terms of the oxygen and helium ion implantation parameters used and the specific tests: microhardness, electrochemical corrosion test, SEM and XRD that were used. It thus presents useful new results which allows one to draw conclusions as to the suitability of the Helium and Oxygen ion implanted AISI 316L stainless steel for biomedical use.

Implant surgery is generally accepted as the best technique for complete teeth replacement. However, it is also the most demanding technique to implement and the most onerous to the client. It would be helpful to reduce costs and simplify procedures in order that the general public could benefit from implant dentistry. This paper reports a robotic system developed with the objective of studying stress/strain distribution caused by implants inserted in blocks of a polymer. The polymer exhibits the same mechanical properties of the human mandible bone.

The system includes an industrial robot manipulator, a data acquisition board, strain gauges for stress/strain evaluation and a force/torque sensor (equipped with accelerometers) placed on the robot wrist. The objective is to optimize the number of implants and their placement/orientation, contributing in this way to reduce the overall cost of implant surgery. The system is presented in detail and explored for drilling and implant insertion.

The preliminary results are encouraging and indicate the usefulness of the system. The three presented situations correspond to general clinical procedures and, as can be concluded from the preliminary results, the intensity of the applied forces increase with the inclination of the drilling tool. Since, the depth of the holes is the same, it can be also concluded that the dissipated energy is superior in the 30° hole. Apart from inclination all the other properties remain constant during the force evaluation; therefore, we expected that during the perforation of the 30° hole the temperature should raise more than in the other types of holes. This aspect will be addressed in detail in the near future (just by carefully monitoring the temperature) because living tissues should not be submitted to temperatures greater than 42°C. The observed fluctuation in the modulus of the force during a drilling cycle suggests that the material is not homogeny. The results indicate that the strain is larger in the vertical load. This might be related with the fact that inclined applied forces imply a distribution of the strain/stress forces at least for two directions.

Further work will include more sensors to obtain all the data.

This will be of interest to the implant industry, since low prices will significantly increase the market and consequently the need for implant products. Currently, implant surgery as well as teeth replacements are based on a few general rules that, very often, do not take into account the specific needs of the patient. This happens independently of clinician expertise, which does not have enough biomechanical information to plan the number, location and orientation of implants in a specific surgery. Consequently, in most of the cases the needs are overestimated, to guarantee long‐term success, which implies expensive procedures and more discomfort for patients.

This work reports on a robotic system to simplify implant procedures.

The purpose of this paper is to use numerical methods and modelling to estimate the effect of a passive, metallic (conducting) implant on eddy currents distribution in a human knee model. There exists a concern among wearers of such implants that they alter electromagnetic field (eddy currents) significantly and there is a need for standardization of that problem.

The numerical model of a human knee has been built on the base of Visual Human Project and electromagnetic field calculations were carried out using Meep FDTD engine. In total, two scenarios have been considered: the knee model with and without a metallic implant. The knee implant model has been prepared as the knee model with overestimated electrical parameters of bone tissues by titanium metal. Alternating eddy current distribution has then been evaluated for both models using FDTD low frequency algorithm.

The highest values of eddy currents occurred on the interface between skin and muscle tissues when the model without an implant is considered. However, when the bone tissues have been replaced with titanium metal, the highest values have occurred in the implant (about 100 times higher than the previous one). This means that an implant can be heated by external electromagnetic fields and that the location of the highest values of eddy currents can be shifted to the proximity of the implant. Moreover, one should realize that in this model the implant is like a knee bone with all anatomical details. It has emerged from this that the implant's shape and size are essential when evaluating its effect on eddy currents distribution.

The interaction of electromagnetic field with implants should be generally further investigated, at least for the presumable worst cases. Such investigation has already been done by some researches but they have been devoted to radio frequencies. The authors believe that the presented research will be helpful in the standardization process, when talking about low frequency electromagnetic field.

The presented methodology can be used in the development of computer aid diagnosis systems. Overestimation of electrical parameters of some parts of the model allows us to predict the distribution of electromagnetic field in the model under investigation very quickly. The results presented in the paper can be used during the standardization process.

To develop a computer‐assisted prefabricated implant design and manufacturing system to improve the esthetic outcome in chin surgery.

Design methods for medical rapid prototyping (RP) of custom‐fabricated chin augmentation implant are presented in this paper. After a careful preoperative planning based on cephalometric tracing for esthetic assessment, helical computed tomography data were used to create a three‐dimensional model of the deficient mandible. Based on these data, the inner surface of the prosthesis was designed to fit the bone surface exactly. The outer geometry was generated from a dried human mandible to create anatomically correct shape prosthesis. The inner and outer surfaces were then connected, and a solid model resulted. A RP system was used for production of the physical models. The surgical planning was performed using the implants and skull models. The resulting SLA implant is used for the production of a mold, which is used to cast the titanium part. Three patients with a congenital small chin or a small and asymmetric mandible underwent reconstruction with individual prefabricated implant. Mean follow‐up period was 1.5 years.

This approach showed significant results in chin augmentation. Compared with traditional methods, the intra‐operative fit was excellent. The operating time was reduced. Postoperatively, the patients experienced the restoration of a natural chin contour, so the esthetic outcome was pleasing. Over the mean follow‐up period of 1.5 years, there were no complications and no implant had to be removed. Long‐term excellent esthetic outcomes by using this new technique have recently been reported.

The methods described above suffer from certain limitations. The registration of the mandible template to create the augmentation image requires high skills of the designer. In addition, the use of RP model in preoperative preparation is expensive.

This method not only demonstrates the significant progress in the reconstruction of chin defects using CAD/CAM RP and RT, compared with the conventional methods of chin augmentation surgery, but also provides natural geometrical prosthesis contour design and accurate fabrication and precise fitting of the prosthesis. The advantages of using this technique are that the physical model of the implant is fitted on the skull model so that the surgeon can plan and rehearse the surgery in advance and a less invasive surgical procedure and less time‐consuming reconstructive and an adequate esthetic can result.

This clinical case demonstrated the potential value of CAD/CAM and RP‐based custom fitted and anatomically correct shape prosthesis fabrication and presurgical planning in craniofacial surgery.

To understand how parents make the decision to implant their deaf young children with cochlear implants, focusing specifically on the concepts of normality, medicalization, and stigma.

I conducted 33 semi-structured interviews with the hearing parents or parent of children with cochlear implants. In all but two families I interviewed the primary caretaker which in all cases was a mother. In the remaining two interviews, I interviewed both parents together. Because of the relative scarcity of families with children with cochlear implants, and the difficulty in connecting with these families, I used a convenience sample, and I did not stratify it in any way. The only requirement for parents to be interviewed is that they had at least one deaf child who had been implanted with at least one cochlear implant. Although this is a small sample, the findings are transferable to other families with the same sociodemographic characteristics as those in my study.

Parents in the study focused on three key concepts: normality, risk analysis, and being a good parent. Dispositional factors such as the need to be “normal” and the desire for material success for one's children appeared to moderate the cost-benefit calculus.

This interview project concentrated on hearing families who had implanted their deaf children with cochlear implants; it does not include culturally Deaf parents who choose to use American Sign Language (ASL) with their Deaf children. Understanding how Deaf families understand the concepts of normality, medicalization, and stigma would shed light on how a distinctly “abnormal” group (by a statistical conception of normal) – ASL-using Deaf people-explain normality in the face of using a non-typical communication method. One can learn a lot by studying the absence of a phenomena, in this case, not implanting children with cochlear implants. It is possible that the existential threat felt by some Deaf people, specifically the demographic problem presented by cochlear implants, led Deaf educators or parents to resist being the subject of research.

Overwhelmingly the sample was female, and white. Only two participants were male, and none of the participants were non-white. The lack of diversity in the sample does not necessarily reflect a lack of diversity of children receiving cochlear implants. Medicaid, which disproportionately covers families of color, covers cochlear implants in most cases, so low SES/racial intersectionality should not have affected the lack of diversity in the sample. However, the oral schools are all private pay, with few scholarships available, so low SES/racial intersectionality in the sampling universe (all children who attend oral schools), may have played a part in the lack of racial diversity within the sample.

Parents in this study were very specific about the fact that they believed cochlear implants would lead to academic, professional, and personal success. They weaved narratives of normality, medicalization, and stigma through their stories. Normality is an important lens from which to see stories about disability and ability, as well as medical correction. As medical science continues to advance, more and more conditions will become medicalized, leading to more and more people taking advanced medical treatments to address problems that were previously considered “problems with living” that are now considered “medical problems” that can be treated with advanced science.

This chapter's contribution to the sociological cochlear implant literature is it's weaving of narratives about normality, stigma, and medicalization into parental stories about the cochlear implant decision-making process. Most literature about the cochlear implant decision-making process focus on cost-benefit analysis, and logical decision-making processes, whereas this paper focuses on decision-making factors stemming from bias, emotions, and values.

This paper aims to automatically obtain the implant parameter from the CBCT images to improve the outcome of implant planning.

This paper proposes automatic simulated dental implant positioning on CBCT images, which can significantly improve the efficiency of implant planning. The authors introduce the fusion point calculation method for the missing tooth's long axis and root axis based on the dental arch line used to obtain the optimal fusion position. In addition, the authors proposed a semi-interactive visualization method of implant parameters that be automatically simulated by the authors' method. If the plan does not meet the doctor's requirements, the final implant plan can be fine-tuned to achieve the optimal effect.

A series of experimental results show that the method proposed in this paper greatly improves the feasibility and accuracy of the implant planning scheme, and the visualization method of planting parameters improves the planning efficiency and the friendliness of system use.

The proposed method can be applied to dental implant planning software to improve the communication efficiency between doctors, patients and technicians.

This research aims to reveal the working principles of the decision mechanism that affects the use of neural implant acceptance and to discuss the leading role of digital literacy in this mechanism. In addition, it aimed to examine the theoretical connections of the research model with the conservation of resources (COR) and technology acceptance model (TAM) theories in the discussion.

The authors collected data from 300 individuals in an organization operating in the health sector and analyzed the data in the Smart Partial Least Squares (PLS) 3.3.3. This way, the authors determined the relationships between the variables, the path coefficients and the significance levels.

The study has found that strong digital literacy skills are linked to positive emotions and attitudes. Additionally, maintaining a positive mindset can improve one's understanding of ethics. Ethical attitudes and positive emotions can also increase the likelihood of adopting neural implants. Therefore, it is crucial to consider both technical and ethical concerns and emotions when deciding whether to use neural implants.

The research results determined the links between the cognitive, emotional and ethical factors in the cyborgization process of the employees and gave original insights to the managers and employees.

1. Determination of antecedents that affect individuals' acceptance of neural implant use.

2. Application to 300 individuals working in a health organization.

3. Path analysis using the least squares method via Smart PLS 3.3.3

4. Significant path coefficients among digital literacy, positive emotions, attitude, ethical understanding and acceptance of neural implant use.

Determination of antecedents that affect individuals' acceptance of neural implant use.

Application to 300 individuals working in a health organization.

Path analysis using the least squares method via Smart PLS 3.3.3

Significant path coefficients among digital literacy, positive emotions, attitude, ethical understanding and acceptance of neural implant use.

The purpose of this paper is to determine the electric field and specific absorption rate (SAR) distribution within biological tissues in the vicinity of dental implants, exposed to the mobile phone radiation.

This research was performed for the frequency of 2.6 GHz, which corresponds to 4G mobile network. The adequate 3D realistic numerical models of the mobile phone user’s head, dental implants and actual smartphone model are created using packages based on the finite integral technique numerical method.

The obtained results yield to a conclusion that the presence of dental implants affects the increase in electric field intensity and SAR values within biological tissues in its vicinity.

The presented procedure is limited to the 4G mobile network frequency of 2.6 MHz. The study should be extended to other mobile network frequencies to be more general.

The criteria for selection of the materials used for dental implants production should be extended with the recommended material characteristics related to their influence on the electric field and SAR distribution, to keep their values in the limits prescribed by standards.

The obtained results provide the foundation for future research in mobile devices’ electromagnetic fields’ influence on human health.

The accurate determination of the electric field and SAR values within different biological tissues and organs in the vicinity of dental implants exposed to mobile phone electromagnetic radiation, demands highly realistic model of observed biological structures. For purposes of the current study, the procedure for modeling of highly nonhomogeneous structure with finite number of homogenous domains having known electromagnetic parameters is described in the paper. As a result, the 3D complex users’ head model formed of 16 homogeneous domains of different electromagnetic parameters is created.

This study aims to design and fabricate a customized multi-rooted dental implant (MRDI) for a canine strategic tooth to reduce surgical time/effort, and better assembly features, leading to enhanced primary and secondary stability and load-bearing capabilities by direct-metal laser sintering (DMLS).

A fractured tooth of a male German Shepherd three-year-old dog (extracted from a cadaver) was selected as the subject for the proposed work. The computer-aided design model of the implant was developed on SOLIDWORKS after a detailed review of literature and consultation with a veterinary doctor about the surgical procedures. Static stress analysis on the implant assembly and residual stress analysis with boundary distortion were performed on each part of the implant subassembly to ensure the fool-proof design.

The functional prototype of the innovative MRDI assembly through DMLS was successfully prepared with acceptable dimensional stability, surface roughness (Ra) and refined microstructure. The 3D printed functional prototype was observed to be residual stress-proof during printing and can bear up to 800 N bite force (required for an adult dog).

Innovative MRDI assembly has been 3D printed by using 17–4 precipitate hardened stainless steel without compromising the strength and can be implanted without bone grafting for better primary stability. Also, the prepared implant will be better for secondary stability due to enhanced osseointegration.

The purpose of this paper is to verify the feasibility and evaluate the compressive properties of Ti6Al4V implants with controlled porosity via electron beam melting process. This process might be a promising method to fabricate orthopedic implants with suitable pore architecture and matched mechanical properties.

Ti6Al4V implants with controlled porosity are produced using an electron beam melting machine. A scanning electron microscope is utilized to examine the macro‐pore structures of the Ti6Al4V implants. The compressive test is performed to investigate the mechanical properties of the porous implants.

The fabricated samples show a fully interconnected open‐pore network. The compressive yield strength of the Ti6Al4V implants with the porosity of around 51 percent is higher than that of human cortical bone. The Young's modulus of the implants is similar to that of cortical bone.

The surface of samples produced by electron beam melting process is covered with loosely spherical metal particles. Polishing and ultrasonic cleaning have to be used to remove the loose remnants.

This paper presents the potential application in the fabrication of orthopedic or dental implants using electron beam melting process.