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This investigation presents a critical analysis of mouthguard production, focusing on the evaluation of conventional vs additive manufacturing methods, the materials involved, and aspects such as their failure and prevention. It also summarizes the current trends, perspectives, and the main limitations. It is shown that some of the shortcomings can be solved by implementing additive manufacturing technologies, which are systematically reviewed in this research. Due to the specific materials used to produce mouthguards, there are certain additive manufacturing technologies that dominate and a wide variety of raw materials. The costs vary depending on the technology.
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OBJECTIVE: To formulate an experimental methacrylate-based photo-polymerizable resin for 3D printing with ytterbium trifluoride as filler and to evaluate the mechanical, physicochemical, and biological properties. METHODS: Resin matrix was formulated with 60 wt% UDMA, 40 wt% TEGDMA, 1 wt% TPO, and 0.01 wt% BHT. Ytterbium Trifluoride was added in concentrations of 1 (G1 %), 2 (G2 %), 3 (G3 %), 4 (G4 %), and 5 (G5 %) wt%. One group remained without filler addition as control (GC). The samples were designed in 3D builder software and printed using a UV-DLP 3D printer. The samples were ultrasonicated with isopropanol and UV cured for 60 min. The resins were tested for degree of conversion (DC), flexural strength, Knoop microhardness, softening in solvent, radiopacity, colorimetric analysis, and cytotoxicity (MTT and SRB). RESULTS: Post-polymerization increased the degree of conversion of all groups (p < 0.05). G2 % showed the highest DC after post-polymerization. G2 % showed no differences in flexural strength from the G1 % and GC (p > 0.05). All groups showed a hardness reduction after solvent immersion. No statistical difference was found in radiopacity, softening in solvent (ΔKHN%), colorimetric spectrophotometry, and cytotoxicity (MTT) (p > 0.05). G1 % showed reduced cell viability for SRB assay (p < 0.05). SIGNIFICANCE: It was possible to produce an experimental photo-polymerizable 3D printable resin with the addition of 2 % ytterbium trifluoride as filler without compromising the mechanical, physicochemical, and biological properties, comparable to the current provisional materials.
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Dureza , Teste de Materiais , Metacrilatos , Impressão Tridimensional , Metacrilatos/química , Resistência à Flexão , Polimerização , Polietilenoglicóis/química , Resinas Compostas/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Colorimetria , Propriedades de SuperfícieRESUMO
Sea urchin species are ecologically important in the Gulf of California and are becoming popular as a local fishery due to their commercial value. The most abundant species are Echinometra vanbrunti, Eucidaris thouarsii, and Tripneustes depressus. The objective of this study was to evaluate cadmium, lead, copper, zinc, and iron concentrations, as well as stable isotope values in these sea urchin species in the Santa Rosalia mining area (STR), in three sites: Punta Gorda, Punta el Aterrizaje, and Punta Salina. The highest Fe concentration (100.2 mg kg-1) was found in E. vanbrunti, while the highest concentrations of Pb (15.1 mg kg-1), Cu (14.5 mg kg-1), and Zn (347.7 mg kg-1) were recorded in E. thouarsii, and the highest Cd concentration (10.8 mg kg-1) was found in T. depressus. The main health risk of trace metal pollution in STR may be caused by Cd and Pb. δ15N and δ13C values were higher in E. thouarsii and T. depressus, respectively; E. thouarsii has the highest trophic position. Specimen size was not related to metal concentrations, but a positive relationship was observed between specimen size and isotopic values in T. depressus. The three species showed different bioaccumulation patterns for the metals analyzed. Additionally, collection sites and seasons play an important role in the variability of metal concentration.
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Monitoramento Ambiental , Ouriços-do-Mar , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/análise , Metais Pesados/análise , Cadeia Alimentar , MéxicoRESUMO
The objective of the present study was to evaluate a blend of functional oils (FO) composed of copaiba and garlic essential oils, pepper oleoresin and cashew nut liquid to mitigate the effects of heat stress on productivity, egg quality, organ morphology of the gastrointestinal tract, serum biochemical profile, nutrient metabolism and body temperature of Japanese quail. A completely randomized design was used in a 3 × 2 factorial scheme (without additive; 300 and 500 mg FO/kg of feed x birds raised in a thermal comfort (TC) and heat stress (HS) environment), with 6 replicates of 8 birds per plot. The birds under HS had lower feed intake (P = 0.0000), egg mass (P = 0.0000), laying rate (P = 0.0000) and higher percentage of infertile non-commercial eggs (P = 0.0004), lower head temperature amplitude (P = 0.0000) and higher average of body temperature (P = 0.0312). HS worsened the external and internal quality of the eggs. Birds kept in HS showed higher values of cholesterol (P = 0.0000) and glutamic-pyruvic transaminase (P = 0.0272). The use of 300 and 500 g FO/ton of feed improved the feed conversion (P = 0.0000) and egg mass (P = 0.0000) of the quail bred under HS, respectively, by 8.4 and 7.2% and increased the relative weight of liver (P = 0.0064) and pancreas (P = 0.0492). The use of such additives also provided a higher % of yolk (P = 0.0018) and reduced the percentage of albumen (P = 0.0029) of the eggs produced in TC, in addition to reducing the amplitude of head temperature (P = 0.0484) of birds bred under HS. The breeding of Japanese quail under HS results in negative impacts on the production, physiological and qualitative aspects of the eggs. The use of 300 g/ton of FO in the diet of Japanese quail leads to improvements in feed conversion, increased liver capacity in nutritional metabolism and results in eggs with a higher proportion of yolks, being, therefore, an alternative for feeding quail in a hot climate.
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Additive manufacturing (AM), commonly known as 3D printing, allows for the manufacturing of complex systems that are not possible using traditional manufacturing methods. Nevertheless, some disadvantages are attributed to AM technologies. One of the most often referred to is the defects of the produced components, particularly the porosity. One approach to solving this problem is to consider it as a non-problem, i.e., taking advantage of the defects. Commercially, LAY-FOMM®60 polymer was successfully used in AM through a material extrusion process. This filament is a blend of two polymers, one of them soluble in water, allowing, after its removal from the printed components, the increase in porosity. The defects produced were exploited to evaluate the metallic ion removal capacity of manufactured components using non-potable tap water. Two experimental setups, continuous and ultrasound-assisted methods, were compared, concerning their water cleaning capacity. Results revealed that continuous setup presented the highest metallic ion removal capacity (>80%) for the following three studied metallic ions: iron, copper, and zinc. High water swelling capacity (~80%) and the increase in porosity of 3D-printed parts played a significant role in the ion sorption capacity. The developed strategy could be considered a custom and affordable alternative to designing complex filtration/separation systems for environmental and wastewater treatment applications.
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Bioactive and biodegradable scaffolds that mimic the natural extracellular matrix of bone serve as temporary structures to guide new bone tissue growth. In this study, 3D-printed scaffolds composed of poly (lactic acid) (PLA)-tricalcium phosphate (TCP) (90-10 wt.%) were modified with 1%, 5%, and 10 wt.% of ZnO to enhance bone tissue regeneration. A commercial chain extender named Joncryl was incorporated alongside ZnO to ensure the printability of the composites. Filaments were manufactured using a twin-screw extruder and subsequently used to print 3D scaffolds via fused filament fabrication (FFF). The scaffolds exhibited a homogeneous distribution of ZnO and TCP particles, a reproducible structure with 300 µm pores, and mechanical properties suitable for bone tissue engineering, with an elastic modulus around 100 MPa. The addition of ZnO resulted in enhanced surface roughness on the scaffolds, particularly for ZnO microparticles, achieving values up to 241 nm. This rougher topography was responsible for enhancing protein adsorption on the scaffolds, with an increase of up to 85% compared to the PLA-TCP matrix. Biological analyses demonstrated that the presence of ZnO promotes mesenchymal stem cell (MSC) proliferation and differentiation into osteoblasts. Alkaline phosphatase (ALP) activity, an important indicator of early osteogenic differentiation, increased up to 29%. The PLA-TCP composite containing 5% ZnO microparticles exhibited an optimized degradation rate and enhanced bioactivity, indicating its promising potential for bone repair applications.
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Materiais Biocompatíveis , Regeneração Óssea , Fosfatos de Cálcio , Diferenciação Celular , Proliferação de Células , Células-Tronco Mesenquimais , Osteoblastos , Poliésteres , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Óxido de Zinco , Alicerces Teciduais/química , Fosfatos de Cálcio/química , Poliésteres/química , Regeneração Óssea/efeitos dos fármacos , Engenharia Tecidual/métodos , Células-Tronco Mesenquimais/citologia , Óxido de Zinco/química , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Osteoblastos/citologia , Osteogênese/efeitos dos fármacos , Teste de Materiais , Osso e Ossos , Regeneração Tecidual Guiada/métodos , Humanos , Animais , Fosfatase Alcalina/metabolismo , Módulo de Elasticidade , Porosidade , Propriedades de SuperfícieRESUMO
The maternal diet and egg incubation temperature are some of the factors that can influence the embryonic development and performance of the newly chicks at 15 d of age. This study evaluated the effects of adding a blend of organic acids, essential oils, curcumin, tannins, vitamin E, and zinc microencapsulated in to the diet of female quails (Coturnix coturnix japonica) on their productive, reproductive performance and redox parameters of their eggs and the interaction of maternal diet × incubation temperature on embryo (E16 and E18) and chicks development. At 98 d of age, 64 female quails with a mean body weight of 150 g ± 0.5 were distributed into two treatments: a Basal diet or a diet supplemented with blend (Sannimix). The eggs from each female were incubated at 37.5°C (Control) and 38.5°C (High Temperature) throughout the incubation period. After hatching, chicks were distributed in a 2 (maternal diet) × 2 (incubation temperature) factorial design. Female quails supplemented with Sannimix showed better productive and reproductive performance and produced higher-quality embryos. Their offspring had greater weight at hatch and at 15 d of age. The eggs and offspring of supplemented with Sannimix female quails showed better oxidative stability. At E16 and E18, High Temperature increased yolk sac utilization and gene expression of the growth hormone receptor (GHR). At E16, embryos from supplemented with Sannimix female quail had higher expression of insulin-like growth factor type I (IGFI) and heat shock protein 70 kDa genes. At 15 d of age, highest expression of the GHR and IGFI genes was observed in chicks from female quails fed the Sannimix diet, regardless of incubation temperature. Regarding the maternal diet × incubation temperature an improved result was observed for chicks from female quails fed with Sannimix even when eggs are exposed to High Temperature during the incubation. The supplementation of quail diets with blend Sannimix improves productive and reproductive performance, egg quality and their embryos, as well as their offspring quality.
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This study focuses on designing and evaluating scaffolds with essential properties for bone regeneration, such as biocompatibility, macroporous geometry, mechanical strength, and magnetic responsiveness. The scaffolds are made using 3D printing with acrylic resin and iron oxides synthesized through solution combustion. Utilizing triply periodic minimal surfaces (TPMS) geometry and mask stereolithography (MSLA) printing, the scaffolds achieve precise geometrical features. The mechanical properties are enhanced through resin curing, and magnetite particles from synthesized nanoparticles and alluvial magnetite are added for magnetic properties. The scaffolds show a balance between stiffness, porosity, and magnetic responsiveness, with maximum compression strength between 4.8 and 9.2 MPa and Young's modulus between 58 and 174 MPa. Magnetic properties such as magnetic coercivity, remanence, and saturation are measured, with the best results from scaffolds containing synthetic iron oxides at 1% weight. The viscosity of the mixtures used for printing is between 350 and 380 mPas, and contact angles between 90° and 110° are achieved. Biocompatibility tests indicate the potential for clinical trials, though further research is needed to understand the impact of magnetic properties on cellular interactions and optimize scaffold design for specific applications. This integrated approach offers a promising avenue for the development of advanced materials capable of promoting enhanced bone regeneration.
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Vegetable fibers are increasingly used in biocomposites, but there is a need for further development in utilizing by-products like cocoa husks. Three-dimensional printing, through Fused Filament Fabrication (FFF), is advancing rapidly and may be of great interest for applying biocomposite materials. This study focuses on developing innovative and fully biodegradable filaments for the FFF process. PLA filaments were prepared using cellulose fibers derived from cocoa husks (5% mass ratio). One set of filaments incorporated fibers from untreated husks (UCFFs), while another set utilized fibers from chemically treated husks (TCFFs). The fabricated materials were analyzed using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) techniques, and they were also tested for tensile strength. ANOVA reveals that both UCFFs and TCFFs significantly predict tensile strength, with the UCFFs demonstrating an impressive R2 value of 0.9981. The optimal tensile strength for the filament test specimens was 16.05 MPa for TCFF8 and 13.58 MPa for UCFF8, utilizing the same printing parameters: 70% infill and a layer thickness of 0.10 mm. Additionally, there was an 18% improvement in the tensile strength of the printed specimens using the filaments filled with chemically treated cocoa husk fibers compared to the filaments with untreated fibers.
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The concerning of plastic pollution in different ecosystems has been worsened by the widespread presence. Phthalate esters (PAEs), plasticizers found in everyday products, can migrate into the environment, especially into the oceans. Researches on their effects on cetaceans are still rare. Metabolomics helps assess perturbations induced by exposure to PAEs, which act as persistent endocrine disruptors. Four PAEs (dimethyl phthalate - DMP, diethyl phthalate - DEP, dibutyl phthalate - DBP, and di(2-ethylhexyl phthalate - DEHP) were analyzed, along with cholesterol and fatty acid profiles of P. blainvillei's blubber samples collected in southern Brazil. The study reveals pervasive contamination by PAEs - especially DEHP, present in all samples - with positive correlations between DEP content and animal size and weight, as well as between the DEHP amount and the C17:1 fatty acid. These findings will be relevant to conservation efforts aimed at this threatened species and overall marine ecosystems.