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European Review For Medical and... Nov 2022This study aimed to assess the effects of plasma grafting modification on the micro-push-out adhesive strength and mechanical properties of fiber posts and to assess the...
OBJECTIVE
This study aimed to assess the effects of plasma grafting modification on the micro-push-out adhesive strength and mechanical properties of fiber posts and to assess the stability of these treatment effects.
MATERIALS AND METHODS
Glass-fiber posts were divided into four groups based on the treatment methods used, as follows: (1) Group NT: no treatment; (2) Group PT: Helium (He) plasma treatment; (3) Group PIG: He-plasma-induced post-irradiation grafting; and (4) Group SIG: He-plasma-induced syn-irradiation grafting. The treated fiber posts were bonded using self-adhesive resin cement exposure to air for 0, 1, 6 or 12 hours separately after surface treatment. Micro-push-out adhesive strength, flexural modulus, and flexural strength were measured.
RESULTS
Plasma treatment, post-irradiation grafting, and syn-irradiation grafting improved adhesive strength at the 0-hours level. However, the improved adhesive strength disappeared in group PT after exposure for one or more hours. In group PIG, the adhesive strength after 1-hour exposure was 20.5% lower than that of 0-hour exposure (adhesive immediately after treatment), and no statistically significant differences in adhesive strength were observed between the 1, 6, and 12-hour exposure. In group SIG, no statistically significant differences in adhesive strength were observed among the 0, 1, and 6-hour exposure. Although the adhesive strength was 23% lower at the 12-hour exposure than that of 0-hour exposure in group SIG, the adhesive strength of fiber posts received syn-irradiation grafting still presented the best adhesive strength compared with the other treatment methods. The three-point flexural modulus and strength remained unaffected by the treatment methods used.
CONCLUSIONS
Plasma-induced syn-irradiation grafting provided the ideal improvement and stability in adhesive strength in fiber posts. In addition, plasma-induced grafting modification successfully overcame the surface aging effect caused by plasma treatment alone without affecting the bulk mechanical properties of fiber posts.
Topics: Post and Core Technique; Adhesives
PubMed: 36394732
DOI: 10.26355/eurrev_202211_30134 -
Therapeutic Delivery Dec 2019
Topics: Adhesives; Alginates; Animals; Bivalvia; Chitosan; Polysaccharides
PubMed: 31646940
DOI: 10.4155/tde-2019-0070 -
Nanoscale Dec 2020Microbes employ a variety of strategies to adhere to abiotic and biotic surfaces, as well as host cells. In addition to their surface physicochemical properties (e.g.... (Review)
Review
Microbes employ a variety of strategies to adhere to abiotic and biotic surfaces, as well as host cells. In addition to their surface physicochemical properties (e.g. charge, hydrophobic balance), microbes produce appendages (e.g. pili, fimbriae, flagella) and express adhesion proteins embedded in the cell wall or cell membrane, with adhesive domains targeting specific ligands or chemical properties. Atomic force microscopy (AFM) is perfectly suited to deciphering the adhesive properties of microbial cells. Notably, AFM imaging has revealed the cell wall topographical organization of live cells at unprecedented resolution, and AFM has a dual capability to probe adhesion at the single-cell and single-molecule levels. AFM is thus a powerful tool for unravelling the molecular mechanisms of microbial adhesion at scales ranging from individual molecular interactions to the behaviours of entire cells. In this review, we cover some of the major breakthroughs facilitated by AFM in deciphering the microbial adhesive arsenal, including the exciting development of anti-adhesive strategies.
Topics: Adhesives; Fimbriae, Bacterial; Microscopy, Atomic Force; Nanotechnology; Surface Properties
PubMed: 33289756
DOI: 10.1039/d0nr07492f -
Scientific Reports Jun 2021Conventional anastomoses with interrupted sutures are challenging and inevitably associated with trauma to the vessel walls. The goal of this study was to evaluate a...
Conventional anastomoses with interrupted sutures are challenging and inevitably associated with trauma to the vessel walls. The goal of this study was to evaluate a novel alternative adhesive-based suture-free anastomosis technique that uses an intraluminal stent. Overall, 120 porcine coronary vessels were analyzed in an ex vivo model and were examined for their mechanical (n = 20 per cohort) and hydrostatic strength (n = 20 per cohort). Anastomoses were made using the novel VIVO adhesive with an additional intraluminal nitinol stent and was compared to interrupted suture anastomosis and to native vessels. Sutureless anastomoses withstood pressures 299 ± 4.47 [mmHg] comparable to native vessels. They were performed significantly faster 553.8 ± 82.44 [sec] (p ≤ 0.001) and withstood significantly higher pressures (p ≤ 0.001) than sutured anastomoses. We demonstrate that the adhesive-based anastomosis can also resist unphysiologically high longitudinal tensile forces with a mean of 1.33 [N]. Within the limitations of an in vitro study adhesive-based suture-free anastomosis technique has the biomechanical potential to offer a seamless alternative to sutured anastomosis because of its stability, and faster handling. In vivo animal studies are needed to validate outcomes and confirm safety.
Topics: Adhesives; Anastomosis, Surgical; Animals; Coronary Vessels; Hydrostatic Pressure; Stents; Swine; Tensile Strength
PubMed: 34193930
DOI: 10.1038/s41598-021-92998-z -
BioMed Research International 2021A fluoride-releasing adhesive system is expected to promote mineralization of demineralized dentin/enamel around a composite restoration, thereby contributing to the... (Review)
Review
A fluoride-releasing adhesive system is expected to promote mineralization of demineralized dentin/enamel around a composite restoration, thereby contributing to the longevity of the restoration. Scanning electron microscopic (SEM) and transmission electron microscopic (TEM) observations revealed the formation of an "acid-base resistant zone" (ABRZ) beneath the hybrid layer when dentin was treated with a self-etch adhesive system. A thicker ABRZ was formed from the upper slope to the end of the outer lesion, indicating greater resistance against an acid-base challenge, when a fluoride-releasing self-etch adhesive system was used. The slope formation of a fluoride-releasing adhesive is believed to be due to fluoride-release from the adhesive. Quantitative assessment of the acid resistance was performed at the interface using the region of interest (ROI) mode of a digital image analysis software package. The area of the ABRZ is influenced by the concentration of fluoride release from the adhesive resin. The threshold of fluoride concentration in the adhesive may exist to influence the morphology of the ABRZ. X-ray absorption fine structure (XAFS) analysis of the dentin treated with different concentrations of NaF-mouth rinses suggested that different fluoride concentrations result in the formation of different chemical compounds, such as fluorapatite and CaF-like structures, on the dentin surface. This may explain the differences in TBS values and morphological appearance of the ABRZ. NaF is effective in enhancing the enamel/dentin bond durability and also helps create a high quality of ARBZ to improve the clinical success of restorations.
Topics: Acid Etching, Dental; Acids; Adhesives; Alkalies; Dentin; Fluorides
PubMed: 34368356
DOI: 10.1155/2021/9731280 -
Journal of the Royal Society, Interface Apr 2018This paper describes the use of the electrostatic element of an electrostatic/gecko-like adhesive to repel dust particles, which have been shown to significantly affect...
This paper describes the use of the electrostatic element of an electrostatic/gecko-like adhesive to repel dust particles, which have been shown to significantly affect adhesion and reliability. The result is a non-destructive, non-contact cleaning method that can be used in conjunction with other cleaning techniques, many of which rely on physical contact between the fibrillar adhesive and substrate. The paper focuses on experimental evaluation of the repulsion of 100 μm glass beads as a function of wave shape, frequency, phase number and electrode direction in relation to the gecko-like features. Results show that a two-phase square wave with the lowest practically feasible frequency can remove 100 μm glass beads from a directional gecko-like adhesive with up to 70% efficiency. Finally, using the optimized electrostatic cleaning properties, results show an approximately 25% recovery in shear stress on a rough glass for three contaminated directional gecko-like adhesives after contact with a dusty table.
Topics: Adhesiveness; Adhesives; Animals; Biomechanical Phenomena; Dust; Friction; Lizards; Reproducibility of Results; Static Electricity
PubMed: 29695604
DOI: 10.1098/rsif.2017.0714 -
BMC Ecology and Evolution May 2023Phylliidae are herbivorous insects exhibiting impressive cryptic masquerade and are colloquially called "walking leaves". They imitate angiosperm leaves and their eggs...
Phylliidae are herbivorous insects exhibiting impressive cryptic masquerade and are colloquially called "walking leaves". They imitate angiosperm leaves and their eggs often resemble plant seeds structurally and in some cases functionally. Despite overall morphological similarity of adult Phylliidae, their eggs reveal a significant diversity in overall shape and exochorionic surface features. Previous studies have shown that the eggs of most Phylliidae possess a specialised attachment mechanism with hierarchical exochorionic fan-like structures (pinnae), which are mantled by a film of an adhesive secretion (glue). The folded pinnae and glue respond to water contact, with the fibrous pinnae expanding and the glue being capable of reversible liquefaction. In general, the eggs of phylliids appear to exhibit varying structures that were suggested to represent specific adaptations to the different environments the eggs are deposited in. Here, we investigated the diversity of phylliid eggs and the functional morphology of their exochorionic structure. Based on the examination of all phylliid taxa for which the eggs are known, we were able to characterise eleven different morphological types. We explored the adhesiveness of these different egg morphotypes and experimentally compared the attachment performance on a broad range of substrates with different surface roughness, surface chemistry and tested whether the adhesion is replicable after detachment in multiple cycles. Furthermore, we used molecular phylogenetic methods to reconstruct the evolutionary history of different egg types and their adhesive systems within this lineage, based on 53 phylliid taxa. Our results suggest that the egg morphology is congruent with the phylogenetic relationships within Phylliidae. The morphological differences are likely caused by adaptations to the specific environmental requirements for the particular clades, as the egg morphology has an influence on the performance regarding the surface roughness. Furthermore, we show that different pinnae and the adhesive glue evolved convergently in different species. While the evolution of the Phylliidae in general appears to be non-adaptive judging on the strong similarity of the adults and nymphs of most species, the eggs represent a stage with complex and rather diverse functional adaptations including mechanisms for both fixation and dispersal of the eggs.
Topics: Animals; Adhesives; Phylogeny; Neoptera; Walking; Insecta
PubMed: 37161371
DOI: 10.1186/s12862-023-02119-9 -
Journal of Experimental Botany Feb 2022The climbing passion flower Passiflora discophora features branched tendrils with multiple adhesive pads at their tips allowing it to attach to large-diameter supports...
The climbing passion flower Passiflora discophora features branched tendrils with multiple adhesive pads at their tips allowing it to attach to large-diameter supports and to flat surfaces. We conducted tensile tests to quantify the performance of this attachment system. We found that the force at failure varies with substrate, ontogenetic state (turgescent or senescent), and tendril size (i.e. tendril cross-sectional area and pad area). The tendrils proved to be well balanced in size and to attach firmly to a variety of substrates (force at failure up to 2N). Pull-off tests performed with tendrils grown on either epoxy, plywood, or beech bark revealed that senescent tendrils could still bear 24, 64, or 100% of the force measured for turgescent tendrils, respectively, thus providing long-lasting attachment at minimal physiological costs. The tendril main axis was typically the weakest part of the adhesive system, whereas the pad-substrate interface never failed. This suggests that the plants use the slight oversizing of adhesive pads as a strategy to cope with 'unpredictable' substrates. The pads, together with the spring-like main axis, which can, as shown, dissipate a large amount of energy when straightened, thus constitute a fail-safe attachment system.
Topics: Adhesives; Biomechanical Phenomena; Biophysics; Passiflora
PubMed: 34673926
DOI: 10.1093/jxb/erab456 -
Journal of Medicine and Life Jun 2022The cause of all small bowel obstruction in 60-75% of cases is adhesive development. The first and main method for adhesion prevention is undoubtedly the surgical...
The cause of all small bowel obstruction in 60-75% of cases is adhesive development. The first and main method for adhesion prevention is undoubtedly the surgical technique, but the prevention of adhesive development is still actual. We aimed to study macroscopic and microscopic peculiarities of the intestine, peritoneum, and scars of the anterolateral abdominal wall. Also, immunological blood changes were observed in rats with the experimental created adhesive disease on the background of azathioprine introduction. The experiment was conducted on 40 rats divided into 2 subgroups: 20 animals as an experimental group (EG1) and 20 as a control group (CG1). Animals from EG received azathioprine (Moshimerampreparaty named by N.A. Semashko, Russia) in a dosage of 1 mg/100g of weight once a day for the first 3 days (starting from the day of surgery). The control group did not receive any drugs. All 40 rats survived the postoperative period. Rats were removed from the experiment on the 7 day after the operation. There were significant statistical differences in most indicators between the experimental and control groups. Phagocytic index (PI) was reduced by 4.55 due to the natural reaction of the rat organism to the surgery. Indicators of EG were a slight decrease in leukocytes and lymphocytes by 0.3 and 0.9, respectively, a moderate decrease in T-lymphocytes by no more than 2.0, and a decrease in phagocytic activity by 5.8. Immunosuppression with azathioprine significantly reduced the frequency and severity of the adhesive process of the abdominal cavity. Used in the recommended dose does not significantly inhibit important indicators of immunity and does not affect wound healing processes.
Topics: Adhesives; Animals; Azathioprine; Immunosuppression Therapy; Peritoneum; Rats; Tissue Adhesions
PubMed: 35928349
DOI: 10.25122/jml-2021-0371 -
Molecules (Basel, Switzerland) Jun 2022In this study, a row of four analogous dopamine acryl- and methacrylamide derivatives, namely -(3,4-dihydroxyphenyethyl) acrylamide, -(3,4-dihydroxyphenyethyl) meth...
In this study, a row of four analogous dopamine acryl- and methacrylamide derivatives, namely -(3,4-dihydroxyphenyethyl) acrylamide, -(3,4-dihydroxyphenyethyl) meth acrylamide, -phenethyl methacrylamide, -(4-hydroxyphenethyl) methacrylamide were synthesized and characterized by H-NMR and C-NMR, followed by further solvent-based radical polymerization with -hydroxyethyl acrylamide. All copolymers were characterized by H-NMR, dynamic differential calorimetry, and gel permeation chromatography. The dependency of the used comonomer ratios to the molecular mass of the corresponding copolymers has been described. The synthesis of the various polymers serves as a feasibility study and provides important data for a future biometric application in the medical field. We synthesized -(3,4-dihydroxyphenyethyl) acrylamide copolymer up to 80 mol% by free radical polymerization without using any protecting groups. All polymers show identical perfect adhesive properties by a simple scratch test. Further, the monomers were used as a photo reactive glue formulation to test its adherence to a medical titanium surface sample by tensile shear test.
Topics: Acrylamide; Acrylamides; Acrylic Resins; Adhesives; Catechols; Methacrylates; Polymers
PubMed: 35807272
DOI: 10.3390/molecules27134027