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Journal of Materials Chemistry. B Apr 2023Materials research relating to bio-based polymers and composites has become the order of the day and several types of research are being undertaken on these materials.... (Review)
Review
Materials research relating to bio-based polymers and composites has become the order of the day and several types of research are being undertaken on these materials. This is mainly due to the belief in the ability of these polymers and composites to serve as potential alternatives for synthetic polymers and fiber-reinforced composites and to mitigate problems pertaining to environmental pollution. A majority of synthetic fibers and polymers in the market today are developed from nonrenewable petroleum-based materials. These have the potential to harm the natural biodiversity of the environment. On the other hand, the use of bioplastics and biocomposites is supported by a few facts such as low cost, lesser energy consumption during production, and notable mechanical and thermal characteristics. The usage of bio-based fibers and polymers in the manufacture of biocomposites in numerous applications greatly enhance the sustainability by eradicating the problem of waste generation. Considering all the above points, the current review focuses on the synthesis and characterization of bioplastics and biocomposites. An elaborate discussion on the mechanical and thermal properties of these materials has also been made. In addition, this review comprehensively discusses the applications, challenges, and prospects of bioplastics and biocomposites.
Topics: Biopolymers; Polymers
PubMed: 36971198
DOI: 10.1039/d2tb02221d -
The Journal of Evidence-based Dental... Dec 2023The aim of this systematic review was to evaluate the survival and complication rates of resin composite laminate veneers. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The aim of this systematic review was to evaluate the survival and complication rates of resin composite laminate veneers.
METHODS
Randomized controlled trials and cohort studies with a minimum 2-year follow-up assessing survival and complication rates of resin composite laminate veneers on permanent dentition from 1998 to May 2022. Literature searches were conducted in MEDLINE (PubMed), Scopus, and the Cochrane Central Register of Controlled Trials electronic databases. References cited in the related reviews and included full-text articles were also hand-searched to further identify potentially relevant studies.
RESULTS
A total of 827 articles were identified. Twenty-two studies were considered for full-text review after the title and abstract screening stage. After exclusion, 7 studies (3 randomized controlled trials and 4 cohort studies) were included in the systematic review. Three published scales were adopted for the quality and risk of bias assessment. At the survival rate threshold, the overall heterogeneity (I) for randomized controlled trials was 50.5% (P = .108). The overall pooled survival rate of the randomized controlled trials was 88% (95% CI: 81%-94%), with the mean follow-up time ranging from 24 to 97 months. Surface roughness, color mismatch, and marginal discoloration were the most reported complications.
CONCLUSION
Resin composite laminate veneers demonstrated moderately high survival rates for the entire sample and the direct laminate veneer group demonstrated higher survival rates than the indirect approach. Most of the complications were regarded as clinically acceptable with or without reintervention.
Topics: Humans; Dental Porcelain; Composite Resins; Dental Restoration Failure
PubMed: 38035903
DOI: 10.1016/j.jebdp.2023.101911 -
Molecules (Basel, Switzerland) Mar 2020Chitosan derivatives, and more specifically, glycosylated derivatives, are nowadays attracting much attention within the scientific community due to the fact that this... (Review)
Review
Chitosan derivatives, and more specifically, glycosylated derivatives, are nowadays attracting much attention within the scientific community due to the fact that this set of engineered polysaccharides finds application in different sectors, spanning from food to the biomedical field. Overcoming chitosan (physical) limitations or grafting biological relevant molecules, to mention a few, represent two cardinal strategies to modify parent biopolymer; thereby, synthetizing high added value polysaccharides. The present review is focused on the introduction of oligosaccharide side chains on the backbone of chitosan. The synthetic aspects and the effect on physical-chemical properties of such modifications are discussed. Finally, examples of potential applications in biomaterials design and drug delivery of these novel modified chitosans are disclosed.
Topics: Animals; Biocompatible Materials; Chitosan; Drug Delivery Systems; Glycosylation; Humans; Molecular Dynamics Simulation; Nanoparticles; Oligosaccharides; Tissue Engineering
PubMed: 32230971
DOI: 10.3390/molecules25071534 -
Journal of Prosthodontics : Official... Jun 2022To systematically review past studies to determine the effect of various solutions on the color of denture teeth, thus answering the question in regards to which type of... (Review)
Review
PURPOSE
To systematically review past studies to determine the effect of various solutions on the color of denture teeth, thus answering the question in regards to which type of denture teeth has the best optical properties after exposure to various solutions. The method of measuring the color of artificial teeth was also evaluated as a secondary outcome.
MATERIALS AND METHODS
A search of studies that quantitatively investigated the influence of immersion solutions on the color change of denture teeth was conducted. Ovid MEDLINE, PubMed and Scopus databases were searched from 1997 to April 2021. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used during article selection. Data regarding the effect of immersion solutions, accelerated aging and surface treatments on color change were gathered. Methodologies used to assess optical properties were also summarized and compared. The modified CONSORT checklist was used to determine the risk of bias of past studied included in this review.
RESULTS
One hundred thirty-three studies were identified after removing duplicates. Forty-one studies were selected for full-text analysis, and 35 remaining papers met the inclusion criteria and were therefore included in this systematic review. Thirty-two in vitro studies and 3 in vivo studies were included in the review. All studies reported that immersion in various solutions has a significant influence on the change in color and optical properties of denture teeth. However, the discoloration of denture teeth is still clinically acceptable in most studies. Exposure to various solutions also affected the translucency parameter of denture teeth. Most studies also investigated the surface roughness and hardness along with the optical properties, and reported that immersion cycles did not cause changes in surface roughness of denture teeth, while hardness was affected. The optical properties of PMMA denture teeth have been studied extensively, whereas that of CAD/CAM and 3D printed denture teeth is limited.
CONCLUSIONS
Color stability of CAD/CAM milled denture teeth is comparable to conventional PMMA denture teeth. There are contradictory findings in terms of color stability of 3D printed denture teeth as compared to conventional PMMA denture teeth. Staining by coffee is worst among the common beverages and solutions investigated. Denture teeth can show color changes after immersion in staining beverages as early as one week. The degree of discoloration of denture teeth after immersion is time dependent, with the larger extent in the initial phase.
Topics: Acrylic Resins; Color; Materials Testing; Polymethyl Methacrylate; Surface Properties
PubMed: 34516027
DOI: 10.1111/jopr.13429 -
Contact Lens & Anterior Eye : the... Oct 2023To evaluate if topical povidone iodine (alone (PI) or combined with dexamethasone (PI-DXM)) is superior to placebo for treating adenoviral conjunctivitis (AC). (Meta-Analysis)
Meta-Analysis Review
PURPOSE
To evaluate if topical povidone iodine (alone (PI) or combined with dexamethasone (PI-DXM)) is superior to placebo for treating adenoviral conjunctivitis (AC).
METHODS
A systematic review was performed according to Preferred Reporting Items for the Systematic Review and Meta-Analyses (PRISMA) Statement. An electronic search was made on PubMed, Embase and Cochrane Library. Randomized control studies that compared PI or PI-DXM with placebo were included. At least three researchers were involved in all phases. Primary outcomes were AC duration and the number of clinical resolutions during the first week. Secondary outcomes were conjunctival redness and serous discharge one week after starting treatment and the rate of AC complications.
RESULTS
Only five studies met the inclusion criteria. PI-DXM reduced the duration of the disease by 2.4 days (IC95% 4.09-0.71), however this result was based only in one study. PI and PI-DXM did not modify the probability of clinical resolution during the first week; relative risk (RR) = 1.77 (IC95% 0.63-4.96) and 1.70 (IC95% 0.67-4.36). The impact of PI on the probability of pseudomembranes could not be estimated. PI-DXM did not influence the risk of developing subepithelial infiltrates RR = 0.73 (IC95% 0.02-33.38).
CONCLUSIONS
At this time there is great uncertainty about the usefulness of PI on the course of adenoviral conjunctivitis. PI-DXM may have a small effect on AC duration. To make future reviews possible, it is important to standardize the way in which these results are reported. Futures studies should include etiological confirmation, unit of study (eyes vs patients) and report on those aspects that are more relevant for patient quality of life (duration of the disease, development of complications: pseudomembranes and subepithelial infiltrates).
Topics: Humans; Povidone-Iodine; Povidone; Quality of Life; Conjunctivitis
PubMed: 37380515
DOI: 10.1016/j.clae.2023.101873 -
European Review For Medical and... Oct 2023There is an abundance of information on facelifts, blepharoplasties, rhinoplasty, and other cosmetic surgical procedures for the upper third of the face, but little is...
OBJECTIVE
There is an abundance of information on facelifts, blepharoplasties, rhinoplasty, and other cosmetic surgical procedures for the upper third of the face, but little is known about perioral lip rejuvenation. The aim of this article is to examine the existing literature on lip rejuvenation and perioral procedures related to lip rejuvenation. Additionally, this article aims to highlight the importance of addressing perioral areas alongside lip rejuvenation procedures, rather than solely focusing on lip rejuvenation. We also discussed the extensive procedures and materials used for lip rejuvenation, such as hyaluronic acid, botulinum toxin A, abobotulinum, onabotulinum, incobotulinum, prabobotulinum, fat grafts, silicone fillers, human collagen, collagen stimulating procedures such as derma pens and derma rolls, radiation frequency, stem cells, and plasma therapy, as well as the underlying factors that contribute to varying success rates.
MATERIALS AND METHODS
A thorough literature search was done using PubMed, Cochrane, Ebsco search, Google Scholar, Scopus, and Web of Science for the articles pertaining to facial and lip cosmetic surgeries 1995-2020. Keywords for the search included anatomy of the face, facial aging, perioral areas, lip rejuvenation, botox, grafts, facelift, plastic surgery, stem cell therapy, plasma treatment, and cosmetic surgery.
RESULTS
37 articles met the study criteria. 14 out of 37 studies included procedures for lip and perioral region rejuvenation. The remaining 23 studies either involved lip procedures alone or lip procedures in conjunction with facial cosmetic procedures. Lip rejuvenation with perioral enhancement with hyaluronic acid gel demonstrated a 94.3% improvement on the lip fullness scale (LFS) one month after re-treatment. The amalgamation of lip and perioral region rejuvenation produces a synergistic effect. Whereas, sole lip rejuvenation procedures showed short-term results with less patient satisfaction, calling for secondary lip rejuvenation procedures. It was also observed that hyaluronic acid was the most commonly used agent for lip rejuvenation procedures with minimal or no side effects.
CONCLUSIONS
In conjunction with perioral rejuvenation, lip rejuvenation procedures produce more aesthetically appealing results. However, any cosmetic surgical or non-surgical procedure is limited by the nature and composition of the products used. The use of FDA-approved products for rejuvenation is strongly advised to avoid undesirable side effects. Further extensive research is required on the long-term outcomes and adverse effects of stem cell transplants, such as tumor development.
Topics: Humans; Lip; Hyaluronic Acid; Cosmetic Techniques; Rejuvenation; Skin Aging; Collagen
PubMed: 37843317
DOI: 10.26355/eurrev_202310_33929 -
Expert Review of Cardiovascular Therapy May 2021Literature on bioresorbable-polymer-stents (BPS) and second-generation durable-polymer-stents (DPS) in percutaneous coronary intervention (PCI) for all comer CAD is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Literature on bioresorbable-polymer-stents (BPS) and second-generation durable-polymer-stents (DPS) in percutaneous coronary intervention (PCI) for all comer CAD is conflicting.
METHODS
Randomized controlled studies comparing PCI among BPS and second-generation DPS were identified up until May-2020 from online databases. Primary outcomes included are all-cause myocardial infarction (MI), cardiac-death, target-vessel-revascularization (TVR), target-vessel MI (TVMI), and stent-thrombosis (ST). Random effect method of risk ratio and confidence interval of 95% was used.
RESULTS
25 prospective randomized controlled trials with 31,822 patients (BPS = 17,065 and DPS = 14,757) were included in the study. Follow-up ranged between a minimum of 6 months to more than 5 years. Cardiac death (RR 1.02, 95% CI 0.89-1.45, = 0.16) was comparable in BPS and second-generation DPS. Risk of all-cause MI was similar between BPS and DPS (RR 0.97, 95% CI 0.84-1.11, = 0.73). TVMI (RR 0.88, 95% CI 0.69-1.11, = 0.33) and ST rates were also comparable in BPS and DPS groups (RR 1.06, 95% CI 0.80-1.40, = 1.00). Overall TVR had comparable outcomes between BPS and DPS (RR 0.95, 95% CI 0.79-1.14, < 0.001); however, higher TVR was seen among BPS group at follow-up of ≥5 years (RR 1.39, 95% CI 1.12-1.14, = 0.02). Bias was low and heterogeneity was moderate.
CONCLUSION
Patients undergoing PCI treated with BPS had comparable outcomes in terms of cardiac death, TVR, ST, TVMI, and all-cause MI to patients treated with second-generation DPS; however, BPS had higher rates of TVR for follow-up of ≥5-years.
Topics: Absorbable Implants; Coronary Artery Disease; Drug-Eluting Stents; Humans; Myocardial Infarction; Percutaneous Coronary Intervention; Polymers; Randomized Controlled Trials as Topic; Stents; Treatment Outcome
PubMed: 33884943
DOI: 10.1080/14779072.2021.1915769 -
Frontiers in Public Health 2023Micro/nano-plastics (MNPs) are considered a heterogeneous class of environmental contaminants that cause multiple toxic effects on biological species. As the commonly... (Meta-Analysis)
Meta-Analysis
Micro/nano-plastics (MNPs) are considered a heterogeneous class of environmental contaminants that cause multiple toxic effects on biological species. As the commonly used mammalian models to study the effects of MNPs with regard to their toxic effects, the mouse and rat models are making a great contribution to the disciplines of environmental toxicology and medical health. However, the toxic effects of MNPs have not been systematically summarized. Therefore, a systematic review and a meta-analysis of the toxic effects of MNPs on mouse/rat models were conducted. A total of seven main categories were established in this systematic review, and 24 subcategories were further divided according to the specific physiological significance of the endpoint or the classification of the physiological system, which covered all the selected pieces of literature. A total of 1,762 biological endpoints were found, and 52.78% of them were significantly affected. This fact indicates that there are relative factors, including the size, polymer type, concentration, and exposure time of MNPs and different sexes of mouse/rat models that could significantly affect the biological endpoints. These biological endpoints can be classified into various factors, such as the dose-response relationships between MNP concentration and physiological categories of the nervous system, growth, reproduction, digestive tract histopathology, and inflammatory cytokine level, among others. MNPs negatively affected the blood glucose metabolism, lipid metabolism, and reproductive function in mice. The reproductive function in male mice is more sensitive to the toxic effects of MNPs. These findings also provide insights into and directions for exploring the evidence and mechanisms of the toxic effects of MNPs on human health. It is clear that more research is required on the pathological mechanisms at the molecular level and the long-term effects of tissue accumulation.
Topics: Rats; Mice; Male; Humans; Animals; Plastics; Microplastics; Mammals
PubMed: 37275491
DOI: 10.3389/fpubh.2023.1103289 -
Environmental Pollution (Barking, Essex... Jan 2021Microplastics receive significant societal and scientific attention due to increasing concerns about their impact on the environment and human health. Marine mammals are...
Microplastics receive significant societal and scientific attention due to increasing concerns about their impact on the environment and human health. Marine mammals are considered indicators for marine ecosystem health and many species are of conservation concern due to a multitude of anthropogenic stressors. Marine mammals may be vulnerable to microplastic exposure from the environment, via direct ingestion from sea water, and indirect uptake from their prey. Here we present the first systematic review of literature on microplastics and marine mammals, composing of 30 studies in total. The majority of studies examined the gastrointestinal tracts of beached, bycaught or hunted cetaceans and pinnipeds, and found that microplastics were present in all but one study, and the abundance varied between 0 and 88 particles per animal. Additionally, microplastics in pinniped scats (faeces) were detected in eight out of ten studies, with incidences ranging from 0% of animals to 100%. Our review highlights considerable methodological and reporting deficiencies and differences among papers, making comparisons and extrapolation across studies difficult. We suggest best practices to avoid these issues in future studies. In addition to empirical studies that quantified microplastics in animals and scat, ten studies out of 30 (all focussing on cetaceans) tried to estimate the risk of exposure using two main approaches; i) overlaying microplastic in the environment (water or prey) with cetacean habitat or ii) proposing biological or chemical biomarkers of exposure. We discuss advice and best practices on research into the exposure and impact of microplastics in marine mammals. This work on marine ecosystem health indicator species will provide valuable and comparable information in the future.
Topics: Animals; Caniformia; Ecosystem; Environmental Monitoring; Humans; Microplastics; Plastics; Water Pollutants, Chemical
PubMed: 33288297
DOI: 10.1016/j.envpol.2020.116142 -
Clinical Oral Investigations Sep 2023The aim of this systematic review and meta-analysis is to assess the comparative clinical success and survival of intracoronal indirect restorations using gold, lithium... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The aim of this systematic review and meta-analysis is to assess the comparative clinical success and survival of intracoronal indirect restorations using gold, lithium disilicate, leucite, and indirect composite materials.
MATERIAL AND METHODS
This systematic review and meta-analysis were conducted following the Cochrane Handbook for Systematic Reviews of Interventions and PRISMA guidelines. The protocol for this study was registered in PROSPERO (registration number: CRD42021233185). A comprehensive literature search was conducted across various databases and sources, including PubMed/Medline, Embase, Cochrane Library, Web of Science, ClinicalTrials.gov, and gray literature. A total of 7826 articles were screened on title and abstract. Articles were not excluded based on the vitality of teeth, the language of the study, or the observation period. The risk difference was utilized for the analyses, and a random-effects model was applied. All analyses were conducted with a 95% confidence interval (95% CI). The calculated risk differences were derived from the combined data on restoration survival and failures obtained from each individual article. The presence of heterogeneity was assessed using the I statistic, and if present, the heterogeneity of the data in the articles was evaluated using the non-parametric chi-squared statistic (p < 0.05).
RESULTS
A total of 12 eligible studies were selected, which included 946 restorations evaluated over a minimum observation period of 1 year and a maximum observation period of 7 years. Results of the meta-analysis indicated that intracoronal indirect resin composite restorations have an 18% higher rate of failure when compared to intracoronal gold restorations over 5-7 years of clinical service (risk difference = - 0.18 [95% CI: - 0.27, - 0.09]; p = .0002; I = 0%). The meta-analysis examining the disparity in survival rates between intracoronal gold and leucite restorations could not be carried out due to methodological differences in the studies.
CONCLUSIONS
According to the currently available evidence, medium-quality data indicates that lithium disilicate and indirect composite materials demonstrate comparable survival rates in short-term follow-up. Furthermore, intracoronal gold restorations showed significantly higher survival rates, making them a preferred option over intracoronal indirect resin-composite restorations. Besides that, the analysis revealed no statistically significant difference in survival rates between leucite and indirect composite restorations. The short observation period, limited number of eligible articles, and low sample size of the included studies were significant limitations.
CLINICAL SIGNIFICANCE
Bearing in mind the limitations of the reviewed literature, this systematic review and meta-analysis help clinicians make evidence-based decisions on how to restore biomechanically compromised posterior teeth.
Topics: Dental Porcelain; Aluminum Silicates; Composite Resins; Gold
PubMed: 37597003
DOI: 10.1007/s00784-023-05050-x