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

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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Influence of Repeated Applications of 2,4-D on Yield and Juice Quality of Concord Grapes (Vitis labruscana)

Weed Science ◽

10.1017/s0043174500071629 ◽

1991 ◽

Vol 39 (2) ◽

pp. 284-295 ◽

Cited By ~ 12

Author(s):

Alex G. Ogg ◽

M. Ahmed Ahmedullah ◽

Gale M. Wright

Keyword(s):

Field Experiments ◽

Grape Juice ◽

Titratable Acidity ◽

Soluble Solids ◽

First Year ◽

Juice Quality ◽

Wide Range ◽

Concord Grapes ◽

One Year

In two field experiments over a 4-yr period, 2,4-D amine applied up to four times per year from late April to early June at 2.5, 10, and 25 ppmw produced a wide range of symptoms on ‘Concord’ grapes. When 2,4-D symptoms in July were severe, yields were reduced by as much as 85%. However, when 2,4-D symptoms in July were slight (less than 2 on a 0 to 6 visual scale), grape yields were not reduced. A second-order polynomial described well (R2= 0.92) the relationship between symptoms and grape yield. Symptoms of 2,4-D on grape leaves did not persist beyond the year of treatment, although grape yields did not recover fully until the second year after the last 2,4-D treatment In the first year of 2,4-D treatments, low grape yields were correlated with reduced weight and number of berries per cluster. In the second and third year of treatment, low grape yields were correlated with fewer clusters per shoot in addition to lower cluster weight and fewer berries per cluster. When 2,4-D was applied one year only, soluble solids in the grape juice were reduced as much as 9%, although reductions were not related to severity of foliar symptoms. When 2,4-D was applied for three consecutive years, soluble solids in the juice were consistently higher in grapes with moderate to severe 2,4-D symptoms. There were no consistent effects of 2,4-D on juice color or titratable acidity. The pH of fresh juice was increased slightly by 2,4-D with the maximum being 10% after 3 yr of consecutive treatments. In the first subsequent non-treatment year after 3 yr of 2,4-D treatments, juice quality was similar to the quality of nontreated grapes. At a detection limit of 0.05 ppmw, 2,4-D was not detected in the harvested grapes. Based on the results of these experiments, grapes with slight 2,4-D symptoms would not be expected to have reduced yields or reduced juice quality.

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Clinical Efficacy of Hydroxychloroquine or Chloroquine in Patients with COVID-19: An Umbrella Review

Pharmaceutical Sciences ◽

10.34172/ps.2021.66 ◽

2021 ◽

Author(s):

Kavous Shahsavarinia ◽

Morteza Ghojazadeh ◽

Sarvin Sanaie ◽

Leila Vahedi ◽

Mahta Ahmadpour ◽

...

Keyword(s):

Clinical Efficacy ◽

Systematic Reviews ◽

Respiratory Infections ◽

Meta Analysis ◽

The Novel ◽

Efficacy And Safety ◽

Umbrella Review ◽

Wide Range ◽

Novel Coronavirus

Background Many of the known coronaviruses cause a wide range of respiratory infections in humans, and the novel coronavirus is no exception to this rule. Although no drug has yet been discovered to prevent or treat this disease, chloroquine (CQ) and hydroxychloroquine (HCQ) have been widely used in studies showing different results. Methods The present study is an umbrella study. The search was conducted for the articles published from January 2020 to November 2020 using the keywords ("COVID-19" OR "SARS-CoV-2" AND "Hydroxychloroquine" OR "Chloroquine" AND "Systematic Review" OR "Metanalysis"). This study was limited to human samples and systematic reviews with or without meta-analysis. The quality of the articles was also evaluated independently by two researchers. Results To evaluate the clinical efficacy of HCQ and CQ, a total of 176 papers and 643569 cases ranging from patients with mild pneumonia to intubated critically ill patients were evaluated. Finally, 8 studies were included. Conclusion There are conflicting results regarding HCQ or CQ efficacy and safety in the systematic reviews. More evidence is needed to confirm whether these drugs are useful in COVID-19 infection, and their usage as the standard care cannot be recommended based on the majority of the studies included in this umbrella review.

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Human In Situ Study of the effect of Bis(2-Methacryloyloxyethyl) Dimethylammonium Bromide Immobilized in Dental Composite on Controlling Mature Cariogenic Biofilm

International Journal of Molecular Sciences ◽

10.3390/ijms19113443 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3443 ◽

Cited By ~ 6

Author(s):

Mary Melo ◽

Michael Weir ◽

Vanara Passos ◽

Juliana Rolim ◽

Christopher Lynch ◽

...

Keyword(s):

Dental Caries ◽

Dental Materials ◽

Significant Inhibition ◽

Dental Composite ◽

Antibiofilm Activity ◽

Dental Resin ◽

Biofilm Growth ◽

Restorative Treatment ◽

Oral Biofilms

Cariogenic oral biofilms cause recurrent dental caries around composite restorations, resulting in unprosperous oral health and expensive restorative treatment. Quaternary ammonium monomers that can be copolymerized with dental resin systems have been explored for the modulation of dental plaque biofilm growth over dental composite surfaces. Here, for the first time, we investigated the effect of bis(2-methacryloyloxyethyl) dimethylammonium bromide (QADM) on human overlying mature oral biofilms grown intra-orally in human participants for 7–14 days. Seventeen volunteers wore palatal devices containing composite specimens containing 10% by mass of QADM or a control composite without QADM. After 7 and 14 days, the adherent biofilms were collected to determine bacterial counts via colony-forming unit (CFU) counts. Biofilm viability, chronological changes, and percentage coverage were also determined through live/dead staining. QADM composites caused a significant inhibition of Streptococcus mutans biofilm formation for up to seven days. No difference in the CFU values were found for the 14-day period. Our findings suggest that: (1) QADM composites were successful in inhibiting 1–3-day biofilms in the oral environment in vivo; (2) QADM significantly reduced the portion of the S. mutans group; and (3) stronger antibiofilm activity is required for the control of mature long-term cariogenic biofilms. Contact-killing strategies using dental materials aimed at preventing or at least reducing high numbers of cariogenic bacteria seem to be a promising approach in patients at high risk of the recurrence of dental caries around composites.

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A Novel Dental Sealant Containing Dimethylaminohexadecyl Methacrylate Suppresses the Cariogenic Pathogenicity of Streptococcus mutans Biofilms

International Journal of Molecular Sciences ◽

10.3390/ijms20143491 ◽

2019 ◽

Vol 20 (14) ◽

pp. 3491 ◽

Cited By ~ 8

Author(s):

Maria Salem Ibrahim ◽

Ahmed S. Ibrahim ◽

Abdulrahman A. Balhaddad ◽

Michael D. Weir ◽

Nancy J. Lin ◽

...

Keyword(s):

Streptococcus Mutans ◽

Dental Materials ◽

Acid Stress ◽

Dental Resin ◽

Biofilm Inhibition ◽

Biofilm Growth ◽

Dental Sealants ◽

Oral Biofilms ◽

Caries Management ◽

Management Approaches

Cariogenic oral biofilms are strongly linked to dental caries around dental sealants. Quaternary ammonium monomers copolymerized with dental resin systems have been increasingly explored for modulation of biofilm growth. Here, we investigated the effect of dimethylaminohexadecyl methacrylate (DMAHDM) on the cariogenic pathogenicity of Streptococcus mutans (S. mutans) biofilms. DMAHDM at 5 mass% was incorporated into a parental formulation containing 20 mass% nanoparticles of amorphous calcium phosphate (NACP). S. mutans biofilms were grown on the formulations, and biofilm inhibition and virulence properties were assessed. The tolerances to acid stress and hydrogen peroxide stress were also evaluated. Our findings suggest that incorporating 5% DMAHDM into 20% NACP-containing sealants (1) imparts a detrimental biological effect on S. mutans by reducing colony-forming unit counts, metabolic activity and exopolysaccharide synthesis; and (2) reduces overall acid production and tolerance to oxygen stress, two major virulence factors of this microorganism. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches in clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria may be a promising approach to decrease caries in patients at high risk.

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Biological and Chemo-Physical Features of Denture Resins

Materials ◽

10.3390/ma13153350 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3350

Author(s):

Gabriele Cervino ◽

Marco Cicciù ◽

Alan Scott Herford ◽

Antonino Germanà ◽

Luca Fiorillo

Keyword(s):

Chemical Structure ◽

Surface Characteristics ◽

New Materials ◽

Dental Resin ◽

Prosthetic Devices ◽

Dental Resins ◽

Dental Prostheses ◽

Materials Used ◽

Physical Features

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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COVID 19 and Quality of Life In Indian Context

10.5772/intechopen.98477 ◽

2021 ◽

Author(s):

Ganapathy Sankar Umaiorubagam ◽

Monisha Ravikumar ◽

Santhana Rajam Sankara Eswaran

Keyword(s):

Quality Of Life ◽

Mental Health ◽

International Development ◽

The Novel ◽

Physical And Mental Health ◽

The People ◽

Wide Range ◽

Social Belonging ◽

Healthcare Politics

Battling the novel COVID-19 pandemic has caused emotional distress and many nations lost their humans at the fight against the virus. Quality of Life (QOL) has a wide range of contexts, including the fields of international development, healthcare, politics and employment. Standard indicators of the quality of life include wealth, employment, the environment, physical and mental health, education, recreation and leisure time, social belonging, religious beliefs, safety, security and freedom. Being a poor economic country like India, lockdown during COVID 19 devastated occupation, education, recreation and money from the people and the fear of the disease impacts not only on the health of the individuals but also the quality of life of individual is affected.

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Data Science in Economics

10.21203/rs.3.rs-27318/v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Saeed Nosratabadi ◽

Amir Mosavi ◽

Puhong Duan ◽

Pedram Ghamisi ◽

Ferdinand Filip

Keyword(s):

Deep Learning ◽

Data Science ◽

State Of The Art ◽

Hybrid Models ◽

Science Methods ◽

The Novel ◽

Learning Models ◽

Wide Range ◽

Hybrid Machine

Abstract This paper provides the state of the art of data science in economics. Through a novel taxonomy of applications and methods advances in data science are investigated. The novel data science methods and applications are investigated in four individual classes of deep learning models, hybrid deep learning models, hybrid machine learning, and ensemble models. Application domains include a wide range of economics research, from stock market, marketing, E-commerce, to corporate banking, and cryptocurrency. Prisma method, a systematic literature review methodology is used to ensure the quality of the survey. The findings revealed that the trends are on the advancement of hybrid models. On the other hand, based on the accuracy metric it is also reported that the hybrid models outperform other learning algorithms. It is further expected that the trends would go toward the advancements of sophisticated hybrid deep learning models.

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Human in situ Study of the Effect of bis(2-methacryloyloxyethyl) Dimethylammonium Bromide Immobilized in Dental Composite on Controlling Mature Cariogenic Biofilm

10.20944/preprints201810.0170.v1 ◽

2018 ◽

Author(s):

Mary Anne S. Melo ◽

Michael D. Weir ◽

Vanara F. Passos ◽

Juliana P. M. Rolim ◽

Christopher D. Lynch ◽

...

Keyword(s):

High Risk ◽

Dental Caries ◽

Time Course ◽

Significant Inhibition ◽

Dental Composite ◽

Antibiofilm Activity ◽

Dental Resin ◽

Biofilm Growth ◽

Oral Biofilms

Cariogenic oral biofilms cause a considerable amount of recurrent dental caries around composite restorations every year, resulting in unprosperous oral health status and expensive restorative treatment for many patients. Quaternary ammonium monomers that can be copolymerized with the current dental resin systems have been increasingly explored for modulation of dental plaque biofilm growth over dental composite surfaces. Here, we investigated the effect of bis(2-methacryloyloxyethyl) dimethylammonium bromide (QADM), against human overlying mature oral biofilms grown intra-orally in human participants for 7 and 14 days, for the first time. Seventeen volunteers wore palatal devices containing composite specimens containing 10% by mass of QADM or a control composite without QADM. After 7 and 14 days, the adherent biofilms were collected for determination of bacterial counts via colony-forming unit (CFU) counts. The biofilm viability, chronological changes, and percentage coverage were also determined by live/dead staining. QADM composites caused a significant inhibition of S. mutans biofilm formation for up to seven days. No difference in the CFU values were found for the 14-day period. Our findings suggest that (1) QADM composite was successful in inhibiting 1-3 day biofilms in the oral environment in vivo; (2) QADM significantly reduced the portion of S.mutans group in a time course where patients at high risk of caries would develop initial enamel carious lesions; and (3) stronger antibiofilm activity is required for the control of mature long-term cariogenic biofilms. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches into clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria seem to be a promising approach in patients at high risk of recurrence of dental caries around composites.

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