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Bone resorption following tooth loss might compromise retention, stability, and support of conventional removable prostheses, and for this reason, implant-supported overdentures are suggested as a viable alternative for completely edentulous patients. Bars, telescopic attachments, or stud attachments have been used to provide retention through a different mechanism of action based on specific design characteristics. The purpose of this report is to thoroughly describe the applied protocol for the fabrication of an implant overdenture supported by two bars incorporating stud attachments. A 67-year-old male patient presented to the Postgraduate Clinic of the National and Kapodistrian University in Athens seeking dental rehabilitation. The remaining teeth were characterized with poor prognosis, mainly due to their periodontal status. The proposed treatment plan included the placement of four implants in the maxilla and two implants in the mandible and the fabrication of implant-supported overdentures. The diagnostic stages revealed adequate prosthetic space that would enable the fabrication of a bar substructure for the maxillary overdenture. To combine the benefits of bars and stud attachments, two bars with four attachments were fabricated. Evaluation of the delivered prosthesis revealed adequate retention, support, and stability achieved with minimal palatal coverage. Patient’s reported satisfaction and quality of life were increased. Recall appointments at one, six, and twelve months did not reveal any adverse effects or patient’s complaints. According to the present case report, different types of attachments may be used after careful study of each case. More studies are needed to report on different aspects of the chosen treatment plan.

This article reviews 24 years of research focused on science education for students with learning and other disabilities. Our results are based on 53 articles from 2 relevant databases. We hereby present and discuss the results of the most popular topics investigated, which include: constructivism, exploratory learning, hands-on activities, cross-curricular projects, multiple means of representation, cognitive and social skills, group and peer learning, coursebooks, reading strategies, readability and students' assessment. Our results suggest that topics like teacher education, teacher/researcher co-operation, education policy, school administration and curriculum structure are scatteredly investigated. These experimental approaches and interventions may provide insight into teacher training in higher education and can explain controversial concepts regarding the question of "full inclusion, selective inclusion or excellency."

Implants are currently used to serve as abutments for implant-assisted removable partial dentures (IARPDs) to facilitate retention and support of the prosthesis. Implants are proposed in cases of posterior edentulous areas to convert Kennedy Class I or II to Class III or when the preparation of existing teeth to serve as abutments is contraindicated. The purpose of this report is to describe the protocol applied to fabricate an IARPD to restore a Kennedy Class II mandible of an elderly patient by incorporating traditional methods, such as the altered cast technique. Each step of the clinical procedure is thoroughly illustrated to document the selected appointment sequence. The patient was satisfied with the delivered prosthesis that demanded no additional implants to be placed but exploitation of an existing one. IARPDs are a viable and cost-effective solution substantiated by numerous reports with positive effects on patient satisfaction.

Theodora-Kalliopi Samartzi,1 Dimokritos Papalexopoulos,2 Aspasia Sarafianou,2 Stefanos Kourtis2 1Private Dentistry Practice, Athens, Greece; 2Department of Prosthodontics, National and Kapodistrian University of Athens, Athens, GreeceCorrespondence: Dimokritos PapalexopoulosDepartment of Prosthodontics, National and Kapodistrian University of Athens, Athens, GreeceEmail dimpapalex@hotmail.comPurpose: The immediate application of a dentin-bonding agent after tooth preparation and before impression-taking (immediate dentin sealing [IDS]) has been suggested to provide several advantages concerning bacterial microleakage, hypersensitivity, and bonding quality. We reviewed the literature and clarified certain aspects related to each step of IDS application.Materials and Methods: The search strategy comprised an electronic research in MEDLINE, Cochrane, Ovid and Scopus for studies published from January 1990 to December 2020 regarding the IDS technique and including both in vitro and clinical studies.Results: After exclusion of irrelevant or duplicate articles, 88 articles focusing on aspects of the IDS technique were assessed. IDS seems to be advantageous with regard to bond strength, gap formation, bacterial microleakage, and dentin hypersensitivity. However, issues arising from interaction with impression materials, the provisional phase, and conditioning methods before cementation require further investigation.Conclusion: There are no documented reasons preventing clinicians applying IDS in their everyday practice. On the contrary, the presented technique seems to be beneficial in certain aspects regarding indirect restorations.Keywords: IDS, indirect restorations, restorative dentistry, review

Forecasting imbalance volumes are of great importance for the different actors in electricity markets. From a transmission system operator (TSO) perspective, balancing supply and demand in real-time is one of the main operational tasks to ensure the safe and reliable operation of the power system, while market participants also use forecasting tools to enhance their participation strategy in electricity wholesale markets. Over the last few years, the increasing integration of renewable energy sources into the power system has created additional complexity for the problem of accurately determining the imbalance volume. In the present work, a case study of the Greek balancing market is presented and analysed. Different algorithms and a set of external predictors are adopted both from the market and operational perspective and compared for two different forecasting horizons.

Electricity price forecasting (EPF) has become an essential part of decision-making for energy companies to participate in power markets. As the energy mix becomes more uncertain and stochastic, this process has also become important for industrial companies, as their production schedules are greatly impacted by energy costs. Although various approaches have been tested with varying degrees of success, this study focuses on predicting day-ahead market (DAM) prices in different European markets and how this directly affects the optimal production scheduling for various industrial loads. We propose a fuzzy-based architecture that incorporates the results of two forecasting algorithms; a random forest (RF) and a long short-term memory (LSTM). To enhance the accuracy of the proposed model for a specific country, electricity market data from neighboring countries are also included. The developed DAM price forecaster can then be utilized by energy-intensive industries to optimize their production processes to reduce energy costs and improve energy-efficiency. Specifically, the tool is important for industries with multi-site production facilities in neighboring countries, which could reschedule the production processes depending on the forecasted electricity market price.

The upward trend of adopting Distributed Energy Resources (DER) reshapes the energy landscape and supports the transition towards a sustainable, carbon-free electricity system. The integration of Internet of Things (IoT) in Demand Response (DR) enables the transformation of energy flexibility, originated by electricity consumers/prosumers, into a valuable DER asset, thus placing them at the center of the electricity market. In this paper, it is shown how Local Energy Markets (LEM) act as a catalyst by providing a digital platform where the prosumers’ energy needs and offerings can be efficiently settled locally while minimizing the grid interaction. This paper showcases that the IoT technology, which enables control and coordination of numerous devices, further unleashes the flexibility potential of the distribution grid, offered as an energy service both to the LEM participants as well as the external grid. This is achieved by orchestrating the IoT devices through a Consumer Digital Twin (CDT), which facilitates the optimal adjustment of this flexibility according to the consumers’ thermal comfort level constraints and preferences. An integrated LEM-CDT platform is introduced, which comprises an optimal energy scheduler, accounts for the Renewable Energy System (RES) uncertainty, errors in load forecasting, Day-Ahead Market (DAM) feed in/out the tariff, and a fair price settling mechanism while considering user preferences. The results prove that IoT-enabled consumers’ participation in the energy markets through LEM is flexible, cost-efficient, and adaptive to the consumers’ comfort level while promoting both energy transition goals and social welfare. In particular, the paper showcases that the proposed algorithm increases the profits of LEM participants, lowers the corresponding operating costs, addresses efficiently the stochasticity of both energy demand and generation, and requires minimal computational resources.

In this paper we studied the effectiveness of the writing criteria that are proposed to be applied during the construction of physics texts so that students with dyslexia do not confront reading difficulties with them. The effectiveness of the criteria has been assessed by the accomplishment of an investigation among students with and without dyslexia. A physics text that was constructed according to the writing criteria and referred to the concept of the electric current was given to read by all students. Twenty two (22) questions were used in order to assign the recognition of the physical phenomena, the physical quantities, the relations between the physical quantities and the units of measurement by all the students. The results of the investigation showed that the writing criteria helped the students with dyslexia not to have difficulties with the physics text about the "electric current". The only area that students with dyslexia had some difficulties compared to the students without dyslexia was the recognition of the units of measurement.

Working with U.S. policymakers to redesign national organ allocation The Organ Procurement & Transplantation Network (OPTN), which manages transplantation activities in the United States, recently partnered with the MIT Operations Research Center to design and implement novel organ allocation policies that are more equitable, efficient, and inclusive. National organ allocation policies need to strike a delicate balance between efficiency and fairness in multiple objectives, reconciling often disparate value judgments and priorities from many different stakeholders. In "Reshaping National Organ Allocation Policy," T. Papalexopoulos, J. Alcorn, and D. Bertsimas et al. introduced a novel optimization- and machine learning-based framework to aid policy design and navigate challenging fairness-efficiency tradeoffs. The authors collaborated with the OPTN to apply the framework to the design of a new national allocation policy for lungs, which was implemented in March 2023 and is anticipated to reduce waitlist mortality by approximately 20%. Based on this success, the authors are now working toward the redesign of the entire U.S. organ allocation system, including kidneys, pancreata, hearts, and livers. The Organ Procurement & Transplantation Network (OPTN) initiated in 2018 a major overhaul of all U.S. deceased-donor organ allocation policies, aiming to gradually migrate them to a so-called continuous distribution model, with the goal of creating an allocation system that is more efficient, more equitable, and more inclusive. Development of policies within this model, however, represents a major challenge because multiple efficiency and fairness objectives need to be delicately balanced. We introduce a novel analytical framework that leverages machine learning, simulation, and optimization to illuminate policy tradeoffs and enable dynamic exploration of the efficient frontier of policy options. In collaboration with the OPTN, we applied the framework to design a new national allocation policy for lungs. Since March 9, 2023, all deceased-donor lungs in the United States have been allocated according to this policy that we helped design, projected to reduce waitlist mortality by approximately 20% compared with current policy based on simulations. We discuss how we extended our collaboration with the OPTN to the redesign of kidney, pancreas, heart, and liver allocation and how our framework can be applied to other application domains, such as school choice or public housing allocation systems. Supplemental Material: The e-companion is available at https://doi.org/10.1287/opre.2022.0035. [ABSTRACT FROM AUTHOR]

Bone resorption following tooth loss might compromise retention, stability, and support of conventional removable prostheses, and for this reason, implant‐supported overdentures are suggested as a viable alternative for completely edentulous patients. Bars, telescopic attachments, or stud attachments have been used to provide retention through a different mechanism of action based on specific design characteristics. The purpose of this report is to thoroughly describe the applied protocol for the fabrication of an implant overdenture supported by two bars incorporating stud attachments. A 67‐year‐old male patient presented to the Postgraduate Clinic of the National and Kapodistrian University in Athens seeking dental rehabilitation. The remaining teeth were characterized with poor prognosis, mainly due to their periodontal status. The proposed treatment plan included the placement of four implants in the maxilla and two implants in the mandible and the fabrication of implant‐supported overdentures. The diagnostic stages revealed adequate prosthetic space that would enable the fabrication of a bar substructure for the maxillary overdenture. To combine the benefits of bars and stud attachments, two bars with four attachments were fabricated. Evaluation of the delivered prosthesis revealed adequate retention, support, and stability achieved with minimal palatal coverage. Patient's reported satisfaction and quality of life were increased. Recall appointments at one, six, and twelve months did not reveal any adverse effects or patient's complaints. According to the present case report, different types of attachments may be used after careful study of each case. More studies are needed to report on different aspects of the chosen treatment plan. [ABSTRACT FROM AUTHOR]

A conservative approach for restoring deep proximal lesions is to apply an increment of composite resin over the preexisting cervical margin to relocate it coronally, the so-called “deep margin elevation” (DME). A literature search for research articles referring to DME published from January 1998 until November 2021 was conducted using MEDLINE (PubMed), Ovid, Scopus, Cochrane Library and Semantic Scholar databases applying preset inclusion and exclusion criteria. Elevation material and adhesive system employed for luting seem to be significant factors concerning the marginal adaptation of the restoration. This technique does not affect bond strength, fatigue behavior, fracture resistance, failure pattern or repairability. DME and subgingival restorations are compatible with periodontal health, given that they are well-polished and refined. The available literature is limited mainly to in vitro studies. Therefore, randomized clinical trials with extended follow-up periods are necessary to clarify all aspects of the technique and ascertain its validity in clinical practice. For the time being, DME should be applied with caution respecting three criteria: capability of field isolation, the perfect seal of the cervical margin provided by the matrix, and no invasion of the connective compartment of biological width.

The continuous penetration of renewable energy resources (RES) into the energy mix and the transition of the traditional electric grid towards a more intelligent, flexible and interactive system, has brought electrical load forecasting to the foreground of smart grid planning and operation. Predicting the electric load is a challenging task due to its high volatility and uncertainty, either when it refers to the distribution system or to a single household. In this paper, a novel methodology is introduced which leverages the advantages of the state-of-the-art deep learning algorithms and specifically the Convolution Neural Nets (CNN). The main feature of the proposed methodology is the exploitation of the statistical properties of each time series dataset, so as to optimize the hyper-parameters of the neural network and in addition transform the given dataset into a form that allows maximum exploitation of the CNN algorithm’s advantages. The proposed algorithm is compared with the LSTM (Long Short Term Memory) technique which is the state of the art solution for electric load forecasting. The evaluation of the algorithms was conducted by employing three open-source, publicly available datasets. The experimental results show strong evidence of the effectiveness of the proposed methodology.

Background: The purpose of this clinical report is to present a technique for transformation of an existing removable partial denture (RPD) into a transitional complete denture (CD) for an impaired stroke patient. Case Presentation: A 67‐year‐old male who underwent an ischemic stroke 12 months ago presented in the Postgraduate Clinic of the National and Kapodistrian University of Athens, requiring treatment of his remaining teeth and repair of his existing RPD which lacked retention and stability. The treatment plan included placement of amalgam plugs on the remaining teeth which were decoronated due to poor prognosis and modification of the existing RPD to a transitional CD. The procedure included one alginate impression and chairside alteration of the prosthesis with simple means. The new prosthesis managed to improve patient's masticatory ability and reduce the risk for aspiration pneumonia. Conclusion: In the present case report a technique for modifying an existing RPD into a transitional CD for an impaired, stroke patient is described. Reduced treatment time, costs and patient's inconvenience while embracing the benefits provided by the utilization of an existing prosthesis regarding adaptation of the neuromuscular system are among the advantages of the described technique. [ABSTRACT FROM AUTHOR]

Objective: To determine the effect of lifetime maxillofacial changes on dental implants placed in adults, analyze the clinical implications of these changes, identify prognostic factors, and offer possible solutions. Overview: The relationship between implant placement and maxillofacial changes, occurring during not only the active growth period but also the entire span of adulthood, has not been extensively examined. Vertical differences between implants and adjacent teeth due to the ankylotic behavior of the former might be observed at any age and endanger restoration biologically, functionally, and esthetically. Regarding interproximal contacts, firm contact loss may occur within a few months after restoration, resulting in food impaction. Many prognostic factors have been reported, but most do not exhibit a statistically significant association with implant infraocclusion and interproximal contact loss. Incorporation of alternative solutions, accurate treatment planning, strict recall protocols, and retrievability of implant-supported restorations can facilitate efficient management of complications. Conclusion: Maxillomandibular changes throughout adulthood may lead to complications such as implant infraocclusion and interproximal contact loss. Rehabilitation of edentulism should be characterized by well-designed and flexible treatment plans to resolve long-term complications efficiently. Further long-term clinical studies are needed to identify other risk factors. Clinical Significance: Treatment plans for implant therapy should be reconsidered for adults. Careful patient monitoring and early intervention are essential for securing treatment outcomes. [ABSTRACT FROM AUTHOR]

Forecasting imbalance volumes are of great importance for the different actors in electricity markets. From a transmission system operator (TSO) perspective, balancing supply and demand in real-time is one of the main operational tasks to ensure the safe and reliable operation of the power system, while market participants also use forecasting tools to enhance their participation strategy in electricity wholesale markets. Over the last few years, the increasing integration of renewable energy sources into the power system has created additional complexity for the problem of accurately determining the imbalance volume. In the present work, a case study of the Greek balancing market is presented and analysed. Different algorithms and a set of external predictors are adopted both from the market and operational perspective and compared for two different forecasting horizons. [ABSTRACT FROM AUTHOR]