scholarly journals Use of Protein Repellents to Enhance the Antimicrobial Functionality of Quaternary Ammonium Containing Dental Materials

2020 ◽  
Vol 11 (3) ◽  
pp. 54 ◽  
Author(s):  
Leopoldo Torres Jr ◽  
Diane R. Bienek

An advancement in preventing secondary caries has been the incorporation of quaternary ammonium containing (QAC) compounds into a composite resin mixture. The permanent positive charge on the monomers allows for electrostatic-based killing of bacteria. Spontaneous adsorption of salivary proteins onto restorations dampens the antimicrobial capabilities of QAC compounds. Protein-repellent monomers can work with QAC restorations to achieve the technology’s full potential. We discuss the theory behind macromolecular adsorption, direct and indirect characterization methods, and advances of protein repellent dental materials. The translation of protein adsorption to microbial colonization is covered, and the concerns and fallbacks of the state-of-the-art protein-resistant monomers are addressed. Last, we present new and exciting avenues for protein repellent monomer design that have yet to be explored in dental materials.


2020 ◽  
Vol 4 ◽  
pp. 239784732097975
Author(s):  
Stéphanie Boué ◽  
Didier Goedertier ◽  
Julia Hoeng ◽  
Anita Iskandar ◽  
Arkadiusz K Kuczaj ◽  
...  

E-vapor products (EVP) have become popular alternatives for cigarette smokers who would otherwise continue to smoke. EVP research is challenging and complex, mostly because of the numerous and rapidly evolving technologies and designs as well as the multiplicity of e-liquid flavors and solvents available on the market. There is an urgent need to standardize all stages of EVP assessment, from the production of a reference product to e-vapor generation methods and from physicochemical characterization methods to nonclinical and clinical exposure studies. The objective of this review is to provide a detailed description of selected experimental setups and methods for EVP aerosol generation and collection and exposure systems for their in vitro and in vivo assessment. The focus is on the specificities of the product that constitute challenges and require development of ad hoc assessment frameworks, equipment, and methods. In so doing, this review aims to support further studies, objective evaluation, comparison, and verification of existing evidence, and, ultimately, formulation of standardized methods for testing EVPs.



Author(s):  
Gabriel Wilkes ◽  
Roman Engelhardt ◽  
Lars Briem ◽  
Florian Dandl ◽  
Peter Vortisch ◽  
...  

This paper presents the coupling of a state-of-the-art ride-pooling fleet simulation package with the mobiTopp travel demand modeling framework. The coupling of both models enables a detailed agent- and activity-based demand model, in which travelers have the option to use ride-pooling based on real-time offers of an optimized ride-pooling operation. On the one hand, this approach allows the application of detailed mode-choice models based on agent-level attributes coming from mobiTopp functionalities. On the other hand, existing state-of-the-art ride-pooling optimization can be applied to utilize the full potential of ride-pooling. The introduced interface allows mode choice based on real-time fleet information and thereby does not require multiple iterations per simulated day to achieve a balance of ride-pooling demand and supply. The introduced methodology is applied to a case study of an example model where in total approximately 70,000 trips are performed. Simulations with a simplified mode-choice model with varying fleet size (0–150 vehicles), fares, and further fleet operators’ settings show that (i) ride-pooling can be a very attractive alternative to existing modes and (ii) the fare model can affect the mode shifts to ride-pooling. Depending on the scenario, the mode share of ride-pooling is between 7.6% and 16.8% and the average distance-weighed occupancy of the ride-pooling fleet varies between 0.75 and 1.17.



2020 ◽  
Vol 8 (9) ◽  
Author(s):  
Mirla Lays Dantas de Almeida ◽  
Gymenna Maria Tenório Guênes ◽  
Luanna Abílio Diniz Melquiades de Medeiros ◽  
Mylena de Araújo Régis ◽  
Marcus Vinícius Lia Fook ◽  
...  

Introdução: O aumento da demanda pela odontologia estética guiou o desenvolvimento de resinas compostas com melhores propriedades físicas e mecânicas. Por isso, percebe-se que há atualmente disponibilidade de uma grande variedade desse material. Dessa forma faz-se necessário a realização de estudos científicos acerca das resinas composta. Objetivo: Avaliar comparativamente, in vitro, à resistência de duas resinas compostas fotopolimerizáveis encontrados no mercado: a Filtek Z350 XT da 3M e a Zirconfill da Technw, após teste mecânico de compressão e análise estatística dos resultados. Material e método: Quatro amostras de cada resina composta foram submetidas ao teste de resistência à compressão numa máquina de ensaio universal. Os resultados foram analisados estatisticamente através do teste de Mann-Whitney com margem de erro 5.0%. Para digitar os dados e obter os cálculos estatísticos foi utilizado o programa IBM SPSS na versão 23. Resultados: A média da força foi mais elevada na resina Zirconfill do que na resina Z350; entretanto, a mediana foi mais elevada na resina Z350. Para a margem de erro fixada (5,0%) não há comprovação de diferença significativa (p > 0,05) entre as duas resinas em relação à força de resistência analisada. Conclusão: As resinas compostas testadas mostram valores de resistência a compressão semelhantes e não apresentam diferenças relevantes.Descritores: Resinas Compostas; Nanotecnologia; Odontologia.ReferênciasBowen RL. Use of epoxy resins in restorative materials. J Dent Res. 1956;35(3):360-69.Chagas LS. Avaliação da resistência flexural e módulo de elasticidade de uma resina do tipo Bulk Fill em comparação com uma resina convencional [monografia de conclusão de curso]. Santa Cruz do Sul: Universidade de Santa Cruz do Sul - UNISC; 2016.Behr M, Proff P, Kollbeck C, Langriegr S, Kunze J, Handel G et al. The bond strength of the resin-to-zirconia interface using diferente bonding concepts. J Mech Behav Biomed Mater. 2011;4(1):2-8.Rodrigues DS. Análise da porosidade, resistência mecânica e desgaste de cimentos de ionômero de vidro e resina composta [dissertação]. Porto: Faculdade de Ciências da Saúde, Universidade Fernando Pessoa; 2014.Pereira AFV, Miranda Junior WG. Avaliação in vitro da microinfiltração e adaptação marginal em restaurações classe v simulando lesões de abfração: estudo piloto. Arq Cent Estud Curso Odontol Univ Fed Minas Gerais. 2008;44(2):18-25.Ferracane JL. Resin composite – state of the art. Dent Mater. 2011; 27(1):29-38.Han JM, Lin H, Zheng G, Shinya A, Gomi H, Shinya A et al. Effect of nanofiller on wear resistance and surface roughness of resin composites. Chin J Dent Res. 2012;15(1):41-7.Mitra SB, Wu D, Holmes B. An application of nanotechnology in advanced dental materials. J Am Dent Assoc. 2003;134(10):1382-90.Mota EG, Weiss A, Spohr AM, Oshima HMS, Carvalho LMN. Relationship between filler content and selected mechanical properties of six microhybrid composites. Rev odonto cienc. 2011;26(2):151-55.Rosa RS. Propriedades mecânicas de resinas compostas com nanopartículas [tese]. Porto Alegre: Pontifícia Universidade Católica do Rio Grande do Sul, Faculdade de Odontologia; 2010.Souza ALT, Oliveira FMMPC, Moysés MR, Assis CPD, Ribeiro JCR, Dias SC. Avaliação da resistência à compressão de resinas compostas fotopolimerizáveis. Arq Odontol. 2007;43(1):30-5.



Author(s):  
Robert Groarke ◽  
Rajani K. Vijayaraghavan ◽  
Daniel Powell ◽  
Allan Rennie ◽  
Dermot Brabazon


2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Maciej Dobrzynski ◽  
Magdalena Pajaczkowska ◽  
Joanna Nowicka ◽  
Aleksander Jaworski ◽  
Piotr Kosior ◽  
...  

In the article has been presented an analysis of susceptibility of selected dental materials, made in the CAD/CAM technology. The morphology and structural properties of selected dental materials and their composites were determined by using XRPD (X-ray powder diffraction) techniques, as well as the IR (infrared) spectroscopy. Moreover, an adhesion as well as development of biofilm by oral microorganisms has been studied. It has been shown that a degree of the biofilm development on the tested dental materials depended on microorganism genus and species. Streptococcus mutans has demonstrated the best adhesion to the tested materials in comparison with Candida albicans and Lactobacillus rhamnosus. However, the sintered materials such as IPS e.max® and the polished IPS e.max® have showed the best “anti-adhesive properties” in relation to S. mutans and L. rhamnosus that have not formed the biofilm on the polished IPS e.max® sample. Furthermore, S. mutans have not formed the biofilm on both surfaces. On the contrary to S. mutans and L. rhamnosus, C. albicans has demonstrated the adhesive properties in relation to the above-mentioned surfaces. Moreover, in contrast to S. mutans and C. albicans, L. rhamnosus has not formed the biofilm on the polished IPS Empress material.



2019 ◽  
Vol 7 (1) ◽  
pp. 8
Author(s):  
Mohammad Hammo DDS ◽  
Mazen Doumani DDS. MSc. ◽  
Adnan Habib DDS. MSc. PhD

The main goal of vital pulp therapy is to preserve and maintain pulpal health in teeth that have been exposed to caries, trauma, and restorative procedures. This type of endodontic treatment is very important in young permanent teeth that have not reached their complete length and exhibit thin-walled roots and wide open apices. The developments in knowledge of pulpal physiology and immunology, beside to newly introduced dental materials, have changed the treatment approaches for teeth with involved pulps. This report describes a case of a young patient in whom maxillary right central incisor suffered crown fractures because of a traumatic accident. Pulpotomy with MTA were performed in order to achieve apexogenesis and the tooth was restored with a glass ionomer cement and composite resin. The patient was reviewed over 4years. 



1981 ◽  
Vol 46 (3) ◽  
pp. 300-303 ◽  
Author(s):  
Maya Zalkind ◽  
Aliza Rehany ◽  
Abraham Revah ◽  
Noah Stern


1989 ◽  
Vol 33 (4) ◽  
pp. 966-976 ◽  
Author(s):  
Satoshi Miyamoto ◽  
Tetsuichi Takagawa ◽  
Akira Nozaki ◽  
Nobuhiko Yanaka ◽  
Yoshiharu Nakamura ◽  
...  


Author(s):  
Nishil Talati ◽  
Heonjae Ha ◽  
Ben Perach ◽  
Ronny Ronen ◽  
Shahar Kvatinsky

While DRAM cannot easily scale below a 20nm technology node, RRAM suffers far less from scalability issues. Moreover, RRAM’s resistivity enables its use for processing-in-memory (PIM), potentially alleviating the von Neumann bottleneck. Unfortunately, because of technological idiosyncrasies, existing DRAM-centric memory controllers cannot exploit the full potential of RRAM. In this paper, we present the design of a memory controller called CONCEPT. The controller is optimized to exploit unique properties of RRAM to enhance its performance and energy efficiency as well as exploiting RRAM’s PIM capability. We show that with CONCEPT, RRAM can achieve DRAM-like performance and energy efficiency on SPEC CPU 2006 benchmarks. Furthermore, using RRAM PIM capabilities, we show a 5X performance gain on a data-intensive in-memory database workload compared to a state-of-the-art CPU-memory computing model.



2021 ◽  
Vol 72 (1) ◽  
pp. 127-142
Author(s):  
Tien Tran Manh ◽  
Tu Do Ngoc ◽  
Hong Vu Xuan

Over the past two decades, textile-reinforced concrete (TRC) materials have been increasingly and widely used for the strengthening/reinforcement of civil engineering works. Thanks to their many advantages as the durability, considerable bond strength with the reinforced concrete (RC) members, best recycling conditions, the TRC materials are considered as an optimal alternative solution to substitute the traditional strengthening and reinforcing materials FRP (Fiber-Reinforced Polymer). The mechanical behavior of TRC composite has been characterized in previous experimental studies. This paper presents a state-of-the-art review of the mechanical behavior of TRC composite under tensile loading. By inheriting from previous review studies, this paper updates the experimental studies on the tensile behavior of TRC composite in the last decade. The review addresses, firstly the mechanical properties of constituent materials in TRC as reinforcement textile, cementitious matrix, and textile/matrix interface. Secondly, it addresses the tensile behavior of TRC composite, including the characterization methods as well as analyses of its strain-hardening behavior with different phases. The paper then discusses the main factors which influence the mechanical behavior of TRC materials in the available experimental studies. Finally, the conclusion of this review terminates this paper.



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