Biological and Chemo-Physical Features of Denture Resins

In the dental field, the study of materials has always been the basis of the clinical practice. Over the years, with the evolution of materials, it has been possible to produce safe and predictable prosthetic devices, with ever better aesthetic features, biocompatibility and patient satisfaction. This review briefly analyzes the features of dental resin materials to underline the biological, microbiological and chemo-physical characteristics. The main aim of prosthodontics is to rehabilitate patients and therefore improve their quality of life. Dental resins are the main materials used for the production of dentures. Once solidified, these polymers have different mechanical or surface characteristics. The results of the literature on these characteristics were analyzed and some new brand dental resins, known as modern resin, were subsequently evaluated. The new materials are undoubtedly a step forward in the creation of dental prostheses, and also in all subsequent maintenance phases. This review shows how changing the chemical structure of the resins could have microbiological influences on the growth and management of the biofilm, and also physical influences in terms of its mechanical characteristics. The development of new materials is a constant goal in dentistry in order to obtain increasingly predictable rehabilitations.

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Novel Protein-Repellent and Antibacterial Resins and Cements to Inhibit Lesions and Protect Teeth

International Journal of Polymer Science ◽

10.1155/2019/5602904 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Li Cao ◽

Junling Wu ◽

Qiang Zhang ◽

Bashayer Baras ◽

Ghalia Bhadila ◽

...

Keyword(s):

Orthodontic Treatment ◽

The Novel ◽

Dental Resin ◽

Biofilm Growth ◽

New Class ◽

Dental Resins ◽

Wide Range ◽

Oral Biofilms ◽

One Year

Orthodontic treatment is increasingly popular as people worldwide seek esthetics and better quality of life. In orthodontic treatment, complex appliances and retainers are placed in the patients’ mouths for at least one year, which often lead to biofilm plaque accumulation. This in turn increases the caries-inducing bacteria, decreases the pH of the retained plaque on an enamel surface, and causes white spot lesions (WSLs) in enamel. This article reviews the cutting-edge research on a new class of bioactive and therapeutic dental resins, cements, and adhesives that can inhibit biofilms and protect tooth structures. The novel approaches include the use of protein-repellent and anticaries polymeric dental cements containing 2-methacryloyloxyethyl phosphorylcholine (MPC) and dimethylaminododecyl methacrylate (DMAHDM); multifunctional resins that can inhibit enamel demineralization; protein-repellent and self-etching adhesives to greatly reduce oral biofilm growth; and novel polymethyl methacrylate resins to suppress oral biofilms and acid production. These new materials could reduce biofilm attachment, raise local biofilm pH, and facilitate the remineralization to protect the teeth. This novel class of dental resin with dual benefits of antibacterial and protein-repellent capabilities has the potential for a wide range of dental and biomedical applications to inhibit bacterial infection and protect the tissues.

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Possible Causes in Breaking of Dental Implants Research

Materials Science Forum ◽

10.4028/www.scientific.net/msf.907.104 ◽

2017 ◽

Vol 907 ◽

pp. 104-118

Author(s):

Maria Stoicănescu ◽

Eliza Buzamet ◽

Dragos Vladimir Budei ◽

Valentin Craciun ◽

Roxana Budei ◽

...

Keyword(s):

Dental Implants ◽

Dental Implant ◽

Scientific Literature ◽

Surface Characteristics ◽

Raw Material ◽

New Materials ◽

Materials Used ◽

Type Of Failure ◽

First Time ◽

Consequent Increase

Dental implants are becoming increasingly used in current dental practice. This increased demand has motivated manufacturers to develop varieties of product through design, but also looking for new materials used to improve surface characteristics in order to obtain a better osseointegration. But the increase in the use of implants goes to a consequent increase in the number of failures. These failures are caused either by treatment complications (peri-implantitis), by fatigue breakage under mechanical over-stress, by defective raw material, or due to errors during the insertion procedures. Although they are rare, these complications are serious in dentistry. Before to market a dental implant to clinical practitioners, the product is validated among other determinations in number of biocompatibility research. Raw material issues, details about its structure and properties are less published by the scientific literature, but all this are subject of a carefully analysis of the producers. Breaking of dental implants during surgical procedures, during the prosthetic procedures or during use (chewing, bruxism, accidents, etc.), is the second most common cause of loss of an implant after consecutive peri-implantitis rejection. Although the frequency of this type of failure for a dental implant is much smaller than those caused by the peri-implantitis, a detailed study of broken implants can explain possible causes. The use of scanning electron microscopy (SEM) in the study of the cleave areas explain the production mechanism of cleavages, starting from micro-fissures in the alloy used for the production of dental implants. These micro-fissures in weak areas of the implant (anti-rotational corners of the polygons, etc.) could generate a serious risk of cleavage first time when a higher force is applied.

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Surface Characteristics and Microbiological Analysis of a Vat-Photopolymerization Additive-Manufacturing Dental Resin

Materials ◽

10.3390/ma15020425 ◽

2022 ◽

Vol 15 (2) ◽

pp. 425

Author(s):

Ericles Otávio Santos ◽

Pedro Lima Emmerich Oliveira ◽

Thaís Pereira de Mello ◽

André Luis Souza dos Santos ◽

Carlos Nelson Elias ◽

...

Keyword(s):

Additive Manufacturing ◽

Biofilm Formation ◽

Acrylic Resin ◽

Surface Characteristics ◽

Microbiological Analysis ◽

Mean Square ◽

Dental Resin ◽

Irregular Surfaces ◽

Dental Resins ◽

Matrix Production

The wide application of additive manufacturing in dentistry implies the further investigation into oral micro-organism adhesion and biofilm formation on vat-photopolymerization (VP) dental resins. The surface characteristics and microbiological analysis of a VP dental resin, printed at resolutions of 50 μm (EG-50) and 100 μm (EG-100), were evaluated against an auto-polymerizing acrylic resin (CG). Samples were evaluated using a scanning electron microscope, a scanning white-light interferometer, and analyzed for Candida albicans (CA) and Streptococcus mutans (SM) biofilm, as well as antifungal and antimicrobial activity. EG-50 and EG-100 exhibited more irregular surfaces and statistically higher mean (Ra) and root-mean-square (rms) roughness (EG-50-Ra: 2.96 ± 0.32 µm; rms: 4.05 ± 0.43 µm / EG-100-Ra: 3.76 ± 0.58 µm; rms: 4.79 ± 0.74 µm) compared to the CG (Ra: 0.52 ± 0.36 µm; rms: 0.84 ± 0.54 µm) (p < 0.05). The biomass and extracellular matrix production by CA and SM and the metabolic activity of SM were significantly decreased in EG-50 and EG-100 compared to CG (p < 0.05). CA and SM growth was inhibited by the pure unpolymerized VP resin (48 h). EG-50 and EG-100 recorded a greater irregularity, higher surface roughness, and decreased CA and SM biofilm formation over the CG.

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Validation of a Simple HPLC–UV Method for the Determination of Monomers Released from Dental Resin Composites in Artificial Saliva

Methods and Protocols ◽

10.3390/mps3020035 ◽

2020 ◽

Vol 3 (2) ◽

pp. 35

Author(s):

Elisavet-Ioanna Diamantopoulou ◽

Orfeas-Evanggelos Plastiras ◽

Petros Mourouzis ◽

Victoria Samanidou

Keyword(s):

Bisphenol A ◽

Computer Aided Design ◽

Artificial Saliva ◽

Triethylene Glycol ◽

Ceramic Materials ◽

Dental Resin ◽

Dental Resins ◽

Computer Aided ◽

Cad Cam ◽

Materials Used

Bisphenol-A (BPA), bisphenol A glycerolate dimethacrylate (Bis-GMA), triethylene glycol dimethacrylate (TEGDMA), and urethane dimethacrylate (UDMA) are organic monomers that can be released from dental composites into the oral cavity. Over specific concentrations, they can act as endocrine disruptors or cause toxic effects. The purpose of this work is to develop and validate an analytical method to determine BPA, Bis-GMA, TEGDMA, and UDMA monomers released from synthetic dental resins in artificial saliva. The method was validated before its application to new hybrid ceramic materials used in computer-aided design and computer-aided manufacturing (CAD/CAM) restorations to determine the release of monomers in various time intervals (e.g., 24 h, and 7, 14, 30, and 60 days), both in methanolic solutions, as well as in artificial saliva. Chromatographic analysis was performed isocratically on a Perfect Sil Target ODS-3 analytical column (250 mm × 4.6 mm, 5 µm) with CH3CN/H2O, 58/42% v/v as mobile phase within 23 min. The developed method was validated in terms of selectivity, linearity, accuracy, and precision.

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Materials and Methods of Biosensor Interfaces With Stability

Frontiers in Materials ◽

10.3389/fmats.2020.583739 ◽

2021 ◽

Vol 7 ◽

Author(s):

Min Song ◽

Xiaogang Lin ◽

Zhijia Peng ◽

Shibin Xu ◽

Lifeng Jin ◽

...

Keyword(s):

Interface Design ◽

Three Dimensional ◽

Medical Diagnostics ◽

Electrical Signal ◽

Future Perspectives ◽

New Materials ◽

Materials Used ◽

Biological Analytes ◽

Sensing Performance

Biosensors can convert the concentration of biological analytes into an electrical signal or other signals for detection. They are widely used in medical diagnostics, food safety, process control, and environmental monitoring fields. In recent years, new schemes of stable biosensor interfaces have attracted much attention. Interface design is a vital part of biosensor development, since its stability can be directly related to the quality of sensing performance such as sensitivity, stability, and linearity. This review summarized the latest methods and materials used to construct stable biosensor interfaces and pointed some future perspectives and challenges of them. From the literature, we found that nanomaterials, polymers, and their composites such as chitosan, cellulose, and conducting polymers are the most common materials used in the biosensor interface design. Apart from materials, there are increasing developments in monolayer membrane techniques, three-dimensional constructions, and other interface techniques. This review is a study of the latest progress in biosensor interface stability solutions, which may provide some references and innovative directions of biosensor interface design for researchers in biosensor fields and encourage people to further explore new materials and methods.

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CUIDADOS BUCAIS EM PACIENTES VENTILADOS MECANICAMENTE: CONHECIMENTO DE ENFERMEIROS DE UM HOSPITAL ESCOLA

Enfermagem em Foco ◽

10.21675/2357-707x.2017.v8.n4.932 ◽

2018 ◽

Vol 8 (4) ◽

Author(s):

Gérsica Sampaio Silva ◽

Fernanda Alves Ferreira Gonçalves ◽

Bárbara Ribeiro Miquelin Bueno ◽

Georlucya Kátia Da Silva Ferreira ◽

Ludmila Pinheiro Da Silva ◽

...

Keyword(s):

Oral Hygiene ◽

Oral Care ◽

Cross Sectional Study ◽

Cross Sectional ◽

Mechanically Ventilated ◽

Mechanically Ventilated Patients ◽

Complicating Factors ◽

Materials Used ◽

Ventilated Patients

Objetivo: Avaliar o conhecimento acerca dos cuidados bucais realizados por enfermeiros a pacientes ventilados mecanicamente. Método: Estudo transversal, realizado em um hospital escola de Goiânia/Goiás. A coleta de dados deu-se por meio de questionário estruturado. Resultados: Os enfermeiros conhecem as medidas recomendadas sobre higiene bucal. Os fatores dificultadores encontrados foram a falta de pessoal (21,7%), falta de tempo (16,7%) e trabalhos burocráticos (15%). Contudo ainda existem lacunas no que se refere a produtos e materiais utilizados na higiene bucal. Conclusão: As Lacunas e os fatores dificultadores sinalizados nesse estudo merecem reflexão, como forma de avaliar a qualidade do cuidado oferecido.Descritores: Biofilme; Higiene Bucal; Cuidados de enfermagem.ORAL CARE IN MECHANICALLY VENTILATED PATIENTS: KNOWLEDGE OF NURSES FROM A SCHOOL HOSPITALObjective: To evaluate the knowledge about oral care performed by nurses in mechanically ventilated patients. Methods: a cross-sectional study, conducted in a teaching hospital of Goiania/Goias. The data collection was performed by means of a structured questionnaire. Results: The nurses know the measures recommended on oral hygiene. The complicating factors found were the lack of personnel (21.7%), lack of time (16.7%) and work on tape (15%). However there are still gaps in relation to products and materials used in oral hygiene. Conclusion: The gaps and the factors complicating factors indicated in this study deserve consideration, as a means of evaluating the quality of care offered.Keywords: Biofilm; Oral hygiene; Nursing care.CUIDADO ORAL EN PACIENTES CON VENTILACIÓN MECÁNICA: EL CONOCIMIENTO DE LAS ENFERMERAS DEL HOSPITAL ESCUELAObjetivo: Evaluar el conocimiento sobre el cuidado bucal realizadas por enfermeras en pacientes ventilados mecánicamente. Métodos: Estudio transversal, realizado en un hospital de Goiania y Goias. La recolección de datos se realizó por medio de un cuestionario estructurado. Resultados: Las enfermeras saben las medidas recomendadas en la higiene bucal. Los factores encontrados fueron la falta de personal (21,7%), la falta de tiempo (16,7%) y trabajar en la cinta (15%). Sin embargo todavía hay lagunas en relación con los productos y los materiales utilizados en la higiene bucal. Conclusión: Las brechas y los factores factores indicados en este estudio merecen consideración, como medio de evaluar la calidad de la atención ofrecida.Palabras clave: Biofilme; Higiene Bucal; Atención de Enfermería.

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EVALUATION OF TRIBOTECHNICAL PROPERTIES OF THE COATING OBTAINED BY ELECTRIC SPARK HARDENING

Tekhnicheskiy servis mashin ◽

10.22314/2618-8287-2020-58-1-157-163 ◽

2020 ◽

Vol 4 (141) ◽

pp. 157-163

Author(s):

IL’YA ROMANOV ◽

◽

ROMAN ZADOROZHNIY

Keyword(s):

Wear Resistance ◽

Reference Sample ◽

Optical Microscope ◽

Research Purpose ◽

Tribotechnical Properties ◽

Uncoated Surface ◽

Before And After ◽

Materials Used ◽

Friction Track

When applying coatings using various methods on the surfaces of moving parts that work in joints, it is important to make sure that the coatings are strong and wear-resistant in order to return them to their original resource. All existing hardening technologies and materials used to perform coatings have their own characteristics, therefore, the quality of the resulting coatings can be judged only after specific tests. (Research purpose) The research purpose is in evaluating the properties of the coating obtained by the method of electric spark hardening, and its ability to resist friction and mechanical wear. (Materials and methods) Authors conducted tests on the basis of the "Nano-Center" center for collective use. A coating was applied on the BIG-4M unit with a VK-8 hard alloy electrode, tribological properties were evaluated on a CSM Instruments TRB-S-DE-0000 tribometer, the width of the friction track was measured after the test using an inverted OLYMPUS gx51 optical microscope, and samples were weighed before and after the test on a VLR-200 analytical balance. Conducted research in accordance with GOST 23.224-86 and RD 50-662-88 guidelines. (Results and discussion) The article presents performed tests on the run-in and wear resistance of the coating. The samples were worked on with a step-by-step increase in the load. During the tests, the friction force was drawed on the diagram. Authors compared the results with the reference sample, an uncoated surface. (Conclusions) The resulting coating has better run-in and wear resistance compared to the standard, and the increase in wear resistance in dry friction conditions is very significant.

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The Physical Context of Child Development

Current Directions in Psychological Science ◽

10.1177/0963721420980719 ◽

2021 ◽

Vol 30 (1) ◽

pp. 41-48

Author(s):

Gary W. Evans

Keyword(s):

Child Development ◽

Observational Studies ◽

Physiological Stress ◽

Personal Characteristics ◽

Adverse Outcomes ◽

Structural Quality ◽

Physical Context ◽

Physical Setting ◽

Physical Features

Child development reflects interactions between personal characteristics and the physical and social environment. Psychology, however, lacks analysis of physical features that influence child development. In this article, I describe a preliminary taxonomy of physical-setting characteristics that can influence child development, focusing on environmental stressors such as noise, crowding, and chaos along with structural quality of housing, day care, and schools. Adverse outcomes associated with suboptimal physical settings during childhood include cognitive and socioemotional difficulties along with chronic physiological stress. Both direct effects on the child as well as indirect effects occurring via significant persons surrounding the child are described. Methodological limitations, particularly reliance on observational studies, are a weakness in the current literature, but increasingly more rigorously obtained findings yield converging evidence of the effects of physical settings on child development.

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Analysis of Quality of Backyard Compost and Its Potential Utilization as a Circular Bio-Waste Source

Applied Sciences ◽

10.3390/app11104392 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4392

Author(s):

Apolka Ujj ◽

Kinga Percsi ◽

Andras Beres ◽

Laszlo Aleksza ◽

Fernanda Ramos Diaz ◽

...

Keyword(s):

Crop Production ◽

Basic Education ◽

Raw Materials ◽

Nutrient Content ◽

Quality Analysis ◽

Weed Seed ◽

Quality Properties ◽

Seed Dispersion ◽

Materials Used

The use and quality analysis of household compost have become very important issues in recent years due to the increasing interest in local food production and safe, self-produced food. The phenomenon was further exacerbated by the COVID-19 pandemic quarantine period, which gave new impetus to the growth of small home gardens. However, the knowledge associated with making high-quality compost is often lacking in home gardeners. Therefore, the objective of this research was to find answers to the following questions: can the quality of backyard compost be considered safe in terms of toxicity and nutrient content? Can weed seed dispersion affect the usability of backyard compost? In general, can the circulation of organic matter be increased with the spread of home composting? In this study, 16 different house composts were analysed for stability, weed seed contamination, toxic elements, and nutrient content using analysis of variance. The results of the research showed that the quality properties of the composts (including their weed seed dispersion effect) were greatly influenced by the different techniques and raw materials used. The toxicity levels, as well as the content of macro and microelements, were within the parameters of safe-quality compost. The specific macronutrient (Ca, Mg) and micronutrient (Fe, Mn) contents of the tested composts have a similar and, in some cases, more favorable nutrient supply capacity in crop production than the frequently-used cow manure-based composts. With a plan of basic education on composting, there is potential to encourage farmyard composting.

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The Impact of Post-Manufacture Treatments on the Surface Characteristics Important for Finishing of OSB and Particleboard

Forests ◽

10.3390/f12080975 ◽

2021 ◽

Vol 12 (8) ◽

pp. 975

Author(s):

Antonio Copak ◽

Vlatka Jirouš-Rajković ◽

Nikola Španić ◽

Josip Miklečić

Keyword(s):

Water Vapour ◽

Oriented Strand Board ◽

Construction Material ◽

Surface Characteristics ◽

Surface Treatments ◽

Factors Affecting ◽

Treatment Conditions ◽

Water Vapour Absorption ◽

The Impact

Oriented strand board (OSB) is a commonly used structural wood-based panel for walls and roof siding, but recently the industry has become interested in OSB as a substrate for indoor and outdoor furniture. Particleboard is mainly used in furniture productions and has become popular as a construction material due to its numerous usage possibilities and inexpensive cost. Moisture is one of the most important factors affecting wood-based panel performance and the post-treatment conditions affected their affinity to water. When OSB and particleboard are used as substrates for coatings, their surface characteristics play an important role in determining the quality of the final product. Furthermore, roughness can significantly affect the interfacial phenomena such as adsorption, wetting, and adhesion which may have an impact on the coating performance. In this research particleboard and OSB panels were sanded, re-pressed and IR heated and the influence of surface treatments on hardness, roughness, wetting, water, and water vapour absorption was studied. Results showed that sanding improved the wetting of particleboard and OSB with water. Moreover, studied surface treatments increased water absorption and water penetration depth of OSB panels, and re-pressing had a positive effect on reducing the water vapour absorption of particleboard and OSB panels.

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