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The elimination of biofilms during root canal therapy continues to pose a challenge due to complex anatomies and uninstrumented portions of the root canal system. The incorporation of nanoparticles in endodontic sealers is an area of interest for potentially enhancing antimicrobial activity and improving treatment outcomes. This systematic review evaluated the antimicrobial effects of various nanoparticles in endodontic sealers. Comprehensive literature review was conducted using the electronic Embase, Web of Science, and PubMed databases followed by citation searching for articles eligible per the inclusion criteria. A total of 1845 citations were screened, of which 13 articles met the inclusion criteria and were included in this review. All included articles were in vitro studies with low-to-moderate quality assessment scores. The incorporation of select nanoparticles was associated with significant enhancement of antibacterial effects in planktonic and/or biofilm forms, whereas other nanoparticles were not. The incorporation of certain types and concentrations of nanoparticles into endodontic sealers displayed antimicrobial effects in vitro. The need for well-designed clinical studies translating in vitro findings into clinical practice is warranted. The incorporation of nanoparticles may enhance the antimicrobial properties of endodontic sealers and may improve treatment outcomes. [ABSTRACT FROM AUTHOR]

Background: Mammalian orthoreovirus type 3 (MRV3), which is responsible for gastroenteritis in many mammalian species including pigs, has been isolated from piglets with severe diarrhea. However, the use of pig-derived cells as an infection model for swineMRV3 has rarely been studied. Objectives: This study aims to establish porcine intestinal organoids (PIOs) and examine their susceptibility as an in vitro model for intestinal MRV3 infection. Methods: PIOs were isolated and established from the jejunum of a miniature pig. Established PIOs were characterized using polymerase chain reaction (PCR) and immunofluorescence assays (IFAs) to confirm the expression of small intestine-specific genes and proteins, such as Lgr5, LYZI, Mucin-2, ChgA, and Villin. The monolayered PIOs and threedimensional (3D) PIOs, obtained through their distribution to expose the apical surface, were infected with MRV3 for 2 h, washed with Dulbecco’s phosphate-buffered saline, and observed. Viral infection was confirmed using PCR and IFA. We performed quantitative realtime reverse transcription-PCR to assess changes in viral copy numbers and gene expressions linked to intestinal epithelial genes and antiviral activity. Results: The established PIOs have molecular characteristics of intestinal organoids. Infected PIOs showed delayed proliferation with disruption of structures. In addition, infection with MRV3 altered the gene expression linked to intestinal epithelial cells and antiviral activity, and these effects were observed in both 2D and 3D models. Furthermore, viral copy numbers in the supernatant of both models increased in a time-dependent manner. Conclusions: We suggest that PIOs can be an in vitro model to study the infection mechanism of MRV3 in detail, facilitating pharmaceutical development. [ABSTRACT FROM AUTHOR]

To evaluate the vertical and horizontal stiffness and rupture strength with freedom of movement in the three axes of the space in vitro of mandibles fixed with 2.0-mm conventional and locking systems in unilateral angle fractures. Twenty mandibles of sheep underwent an osteotomy reproducing a fracture and were divided into three groups according to the fixation used: F1CP - conventional plate on oblique line; F2CP - two conventional plates in a single plane; and FLP - locking system plate on oblique line. A universal test machine was used, with a metal support coupled with wheels for the mandibles. The systems were analyzed in three different moments: pre and post osteotomy/fixation stiffness and rupture strength. Findings were submitted to analysis of variance (p < 0.050). Vertical stiffness, horizontal stiffness and rupture strength between pre and post osteotomy/fixation showed a significant decrease (p < 0.001). In the comparison between the groups, there was a significant difference for vertical stiffness (p = 0.009) and the F2CP group showed greater stiffness. There was no significant difference for the remaining tests. The fixation system with two conventional plates showed higher resistance to vertical stiffness than the other systems, and there was no statistically significant difference between the groups for horizontal stiffness and rupture strength. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to compare the characteristics of fresh and stored feline red blood cells (RBCs) after passage through an 18 μm microaggregate filter. Methods: Nine cats were recruited for a single blood donation using an open collection system. A simulated transfusion using a syringe driver and microaggregate filter was performed over 2 h with half the blood on the day of donation and the other half after 35 days of storage. Differences in haematological parameters, haemolysis percentage and osmotic fragility (OF) were compared on the day of donation pre-filter passage (D0–) vs day of donation post-filter (D0+) or day 35 storage pre-filter (D35–) and post-filter (D35+). Blood was cultured at D0+ and D35+. Results: There were no statistically significant differences in the D0– vs D0+ comparisons. There were statistically significant (P <0.05) increases in haemolysis percentage, red cell distribution width (RDW) percentage and mean OF, and decreases in packed cell volume (PCV), RBC count, haemoglobin and haematocrit for D0– vs D35–. The same was found for D0– vs D35+ with the addition of a significant increase in mean cell haemoglobin (MCH). For D35– vs D35+ only MCH significantly increased. At day 35, 6/9 units had haemolysis percentages that exceeded 1%. This increased to 8/9 of stored units post-filter passage. All blood units cultured negative. Conclusions and relevance: Fresh RBCs exhibited no in vitro evidence of injury following passage through an 18 μm microaggregate filter. Increased MCH was observed in the stored blood and may represent haemolysis induced by the filter. All other changes can be explained by storage lesion rather than filter passage. The findings highlight the importance of blood banking quality controls and the need for further research to assess the effects of transfusion technique, specifically filter passage, on storage lesion-affected feline blood. [ABSTRACT FROM AUTHOR]

Vascular graft infection (VGI) is a feared complication. Prevention is of the utmost importance and vascular graft coatings (VGCs) could offer a potential to do this, with in vitro research a first crucial step. The aim of this study was to summarise key features of in vitro models investigating coating strategies to prevent VGI in order to provide guidance for the setup of future translational research. A comprehensive search was performed in MEDLINE, Embase, and Web of Science. A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. For each database, a specific search strategy was developed. Quality was assessed with the Toxicological data Reliability Assessment Tool (ToxRTool). In vitro models using a VGC and inoculation of the graft with a pathogen were included. The type of graft, coating, and pathogen were summarised. The outcome assessment in each study was evaluated. In total, 4 667 studies were identified, of which 45 papers met the inclusion criteria. The majority used polyester grafts (68.2%). Thirty-one studies (68.9%) included antibiotics, and nine studies (20%) used a commercial silver graft in their protocol. New antibacterial strategies (e.g., proteolytic enzymes) were investigated. A variety of testing methods was found and focused mainly on bacterial adherence, coating adherence and dilution, biofilm formation, and cytotoxicity. Ninety-three per cent of the studies (n = 41) were considered unreliable. Polyester is the preferred type of graft to coat on. The majority of coating studies are based on antibiotics; however, new coating strategies (e.g., antibiofilm coating) are coming. Many in vitro setups are available. In vitro studies have great potential, they can limit the use, but cannot replace in vivo studies completely. This paper can be used as a guidance document for future in vitro research. [ABSTRACT FROM AUTHOR]

The skin is the first line of defense of our body, and it is composed of the epidermis and dermis with diverse immune cells. Various in vitro models have been investigated to recapitulate the immunological functions of the skin and to model inflammatory skin diseases. The simplest model is a two-dimensional (2D) co-culture system, which helps understand the direct and indirect cellto- cell interactions between immune and structural cells; however, it has limitations when observing three-dimensional (3D) interactions or reproducing skin barriers. Conversely, 3D skin constructs can mimic the human skin characteristics in terms of epidermal and dermal structures, barrier functions, cell migration, and cell-to-cell interaction in the 3D space. Recently, as the importance of neuro-immune-cutaneous interactions in the inflammatory response is emerging, 3D skin constructs containing both immune cells and neurons are being developed. A microfluidic culture device called "skin-on-a-chip," which simulates the structures and functions of the human skin with perfusion, was also developed to mimic immune cell migration through the vascular system. This review summarizes the in vitro skin models with immune components, focusing on two highly prevalent chronic inflammatory skin diseases: atopic dermatitis and psoriasis. The development of these models will be valuable in studying the pathophysiology of skin diseases and evaluating the efficacy and toxicity of new drugs. [ABSTRACT FROM AUTHOR]

Copyright of Revista Veterinaria is the property of Universidad Nacional del Nordeste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the biocompatibility and mechanical properties of two commercially available and one experimental periodontal dressing materials. The cytotoxicity of Periobond®, Barricaid® and one experimental periodontal dressing based on Exothane® 8 monomer was tested on 3T3/NIH mouse fibroblast. Genotoxicity was assessed by micronuclei formation, and cell alterations were analyzed using light microscopy. Both biological assays were performed using the eluate obtained from specimens after 24, 72, or 168 hours of incubation. Mechanical characterization was assessed through the ultimate tensile strength and the water sorption and solubility tests. The significance level of a = 0.05 was used for all statistical analyses. All the materials promoted a cell viability lower than 60% in all evaluated times. In general, the cell viability was significantly reduced after 72 and 168h of specimens' incubation. Considering the factor material, there were not statistical differences in the cell viability (p = 0.156). The genotoxicity was not statistically significant among the groups in the different periods of time (p > 0.05). Differences in the ultimate tensile strength values were not statistically significant different among the groups (p = 0.125). Periobond® showed the higher water sorption values (p < 0.001). Regarding solubility, there were no statistical differences between the groups (p = 0.098). All the periodontal dressing materials evaluated in this study exerted a cytotoxic effect against mouse fibroblasts, and their toxicity became more evident over time. Among the materials evaluated, the experimental light-cure type has shown overall similar properties to the commercial references. [ABSTRACT FROM AUTHOR]

Cutaneous leishmaniasis (LC) is an infectious vector-borne disease caused by parasites belonging to the genus Leishmania. Metallic nanoparticles (MNPs) have been investigated as alternatives for the treatment of LC owing to their small size and high surface area. Here, we aimed to evaluate the effect of MNPs in the treatment of LC through experimental, in vitro and in vivo investigations. The databases used were MEDLINE/ PubMed, Scopus, Web of Science, Embase, and Science Direct. Manual searches of the reference lists of the included studies and grey literature were also performed. English language and experimental in vitro and in vivo studies using different Leishmania species, both related to MNP treatment, were included. This study was registered in PROSPERO (CRD42021248245). A total of 93 articles were included. Silver nanoparticles are the most studied MNPs, and L. tropica is the most studied species. Among the mechanisms of action of MNPs in vitro, we highlight the production of reactive oxygen species, direct contact of MNPs with the biomolecules of the parasite, and release of metal ions. MNPs may be considered a promising alternative for the treatment of LC, but further studies are needed to define their efficacy and safety. [Display omitted] • Metallic nanoparticles (MNPs) showed significant leishmanicidal activity against various Leishmania species in both in vitro and in vivo studies. • MNPs induce leishmanicidal effects via oxidative stress, mainly through reactive oxygen species and nitrogen radical species. • The release of metal ions from MNPs disrupts Leishmania 's cellular homeostasis, boosting their leishmanicidal activity. • MNPs in Leishmania also inhibit antioxidant systems, induce mitochondrial dysfunction, and cause lipid peroxidation. • The efficacy of MNPs is influenced by various factors. Biological synthesis has emerged as a promising approach for optimizing MNPs. [ABSTRACT FROM AUTHOR]

Because of the presence of medial calcific sclerosis, both ankle-branchial index and toe pressure measures can yield misleading results when attempting to diagnose peripheral artery disease (PAD). A new ultrasound parameter, maximal systolic acceleration (ACC max), can be an accurate tool for diagnosing PAD, including in diabetic patients. However, it has not been evaluated thoroughly. The aim of this study was to assess the feasibility of using ACC max to diagnose and assess the severity of PAD. The human circulatory system was simulated using an in vitro circulatory system driven by a pulsatile pneumatic pump. Arterial stenosis of various degrees (50%, 70%, 80%, and 90%) was simulated in order to investigate the change in several ultrasound parameters (including ACC max), as well as the intraluminal mean arterial pressure gradient. In a separate set of measurements, interobserver variability was measured using two investigators who were unaware of the degree of stenosis. ACC max significantly decreased (P <.001), and the pressure gradient increased (P <.001) as the degree of stenosis increased. Moreover, we found a strong correlation between ACC max and the pressure gradient (R 2 = 0.937). Finally, interobserver variability with respect to ACC max was extremely low, with an intraclass correlation coefficient of 0.99. The results of this flow model study suggest that ACC max can be a valid, noninvasive tool for diagnosing PAD. Moreover, our finding that ACC max decreases as the severity of stenosis increases, together with the strong correlation between ACC max and the pressure gradient, suggests that ACC max may be useful as an alternative diagnostic tool for assessing the severity of PAD. These promising in vitro data warrant further study in a clinical setting. Limb pressure measurements and the determination of pressure index values (ankle-branchial index and toe pressure) are commonly used in patients with symptoms consistent with peripheral arterial disease. However, ankle-branchial index and toe pressure can be falsely elevated or falsely normal due to medial calcific sclerosis. In this in vitro flow-model study, the maximal systolic acceleration (ACC max) significantly decreased as the degree of stenosis increased. Furthermore, there was a strong correlation between ACC max and the intraluminal pressure gradient. These results suggest ACC max may provide a robust noninvasive technique for assessing the severity of peripheral arterial disease. [ABSTRACT FROM AUTHOR]

Aim: To compare the accuracy of three electronic apex locators in the measurement of the root length of primary teeth with the radiographic and direct visual techniques. Methods: The sample of the in vitro study was 102 root canals of primary molars. For the direct visual technique, the root canal file was introduced into the canal until its tip passed the apical foramen, then it was moved back to the limit of the foramen or root resorption and the measurement was made with a millimetre ruler. For the radiographic measurement, a calibrated and blinded researcher (κ > 0.87) measured the root canals using the same rule. Measurements with apex locators were performed by inserting the file into the canal until the word "Apex" or audible warning to indicate the foramen or resorption. For data analysis, one-way ANOVA for repeated measurements and the Sidak post hoc tests were performed. Results: The direct measurement (µ = 8.57) did not present statistical difference when compared to the Root ZX II measurement (µ = 8.45), as opposed to the radiographic measurements (µ = 8.12), the Endus (µ = 8.24) and iPex II (µ = 8.29). Conclusion: The use of apex locators was superior to the radiographic method and the Root ZX II was the most effective. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the degree of conversion (DC) and the thermal stability of bulk-fill and conventional composite resins. Eleven composite resin samples were prepared to evaluate the DC, Vickers microhardness (VMH), mass and residue/particle loss, glass transition temperature (Tg), enthalpy, and linear coefficient of thermal expansion (CTE) using infrared spectroscopy (FTIR), microdurometer analyses, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dilatometry (DIL). The data were subjected to statistical analysis, with a significance level of 95%. DC and VMH were not influenced by the polymerized side of the sample, and statistical differences were recorded only among the materials. Decomposition temperature, melting, and mass and residue loss were dependent on the material and on the evaluation condition (polymerized and non-polymerized). Tg values were similar between the composites, without statistically significant difference, and CTE ranged from 10.5 to 37.1 (10-6/°C), with no statistical difference between the materials. There was a moderate negative correlation between CTE and the % of load particles, by weight. Most resins had a DC above that which is reported in the literature. TGA, Tg, and CTE analyses showed the thermal behavior of the evaluated composites, providing data for future research, assisting with the choice of material for direct or semidirect restorations, and helping choose the appropriate temperature for increasing the DC of such materials. [ABSTRACT FROM AUTHOR]

Abstract Objective A biomechanical analysis of fixation devices to repair fractures or osteotomies of the mandible is carried out in hemi-mandibles fixed in the condylar process, the force is applied in the molar region and a single movement is allowed. This technical note presents a new setup for evaluating the biomechanics of the mandible with the following improvements: (1) providing freedom of mobility in three axes in the space; (2) applying forces in a way that closely replicates that of real cases; (3) capable of evaluating the fracture resistance and the stiffness and elastic recovery. Method A rigid metal support mounted on bearings was developed that allowed the movement and deformation of the mandible during load application to mimic its freedom of movement when in function. Steadying was only in the mandibular fossae and free in all other regions. Ten fresh sheep mandibles were subjected to testing of their rigidity and capacity for elastic recovery after a displacement of 0.75 mm. Results After three displacement cycles, the mean value of stiffness was 506 ± 64 N/mm, and the mandibles showed visco-elastic recovery. Conclusion This new apparatus and approach is promising for use in the evaluation of mandibular fixations. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of RGO: Revista Gaúcha de Odontologia is the property of RGO: Revista Gaucha de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to evaluate the cytotoxic effect, degree of conversion (% DC), Vickers hardness (VH), and surface morphology of composite resins. Eleven resins, nine bulk-fill resins, and two conventional resins were evaluated. Each material was sampled to evaluate DC (using FTIR), VH, cytotoxicity (using MTT and Neutral Red - NR test), surface morphology (using SEM and AFM), and organic filler (using EDS). All statistical tests were performed with SPSS and the level of significance was set at 0.05. MTT revealed that the materials presented low or no cytotoxic potential in relation to the control. Opus was the resin with the lowest cell viability at a 1:2 concentration at 72 h (32%) and at 7 days (43%), but that significantly increased when the NR test was applied at a 1:2 concentration after 7 days. Thickness and surface subjected to polymerization had no influence on DC, and differences were observed only between the materials. In the microhardness test, statistical differences were observed between the evaluated thicknesses. The bulk-fill resins analyzed in this study exhibited low and/or no cytotoxicity to L929 cells, except for Opus, which showed moderate cytotoxicity according to the MTT assay. When the NR test was used, results were not satisfactory for all composites, indicating the need for different methodologies to evaluate the properties of these materials. The assessed resins demonstrated acceptable physicomechanical properties. [ABSTRACT FROM AUTHOR]

Purpose Infection stones, which comprise approximately 15% of all urinary tract stones, are induced by infection with urease-positive pathogens. The bacteria in the stone matrix present significant treatment impediments compared to metabolic kidney stones. While much is known about how urinary composition regulates metabolic stone formation, there is a general lack of knowledge of which urinary factors regulate the rate of infection stone formation. Unfortunately more in-depth research into infection stones is limited by the lack of suitable models for real-time study of bacterial biofilm formation and stone formation under varying conditions. Materials and Methods We developed an in vitro model to study infection stone formation. The model closely represents the processes that occur in vivo, including the observed migration of ureolytic bacteria (our culture of Proteus mirabilis ) from the bladder to the kidneys, followed by biofilm and stone formation in the kidney. We used scanning electron and confocal laser microscopy, x-ray diffraction, biological counts and dissolved chemical analyses to evaluate the model system. Results Crystals that formed in the system resembled clinically removed struvite stones in structure and composition. Results showed that the degree of ureolysis required to significantly change urine pH was minimal, bacterial communities inhabited the ureter, and upstream colonization and struvite formation required lag time. Conclusions These results have implications for the detection and treatment of struvite stones. Currently this model is being used to study specific urinary factors that regulate struvite formation to identify treatment options, which combined with antibiotics would improve treatment of these stones and decrease recurrence. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study was to evaluate the popcorn technique using a wide range of holmium laser settings and fiber sizes in a systematic in vitro assessment. Materials and Methods Evaluations were done with 4 artificial stones in a collection tube. A fixed ureteroscope was inserted through a ureteral access sheath to provide constant irrigation flow and the laser was placed 1 mm from the bottom. Combinations of 0.5 to 1.5 J, 10 to 20 and 40 Hz, and long and short pulses were tested for 2 and 4 minutes. We used 273 and 365 μm laser fibers. All tests were repeated 3 times. The stones were weighed before and after the experiments to evaluate the setting efficiency. Significant predictors of a highly efficient technique were assessed. Results A total of 144 tests were performed. Mean starting weight of the stones was 0.23 gm, which was consistent among the groups. After the experiment the median weight difference was 0.07 gm (range 0.01 to 0.24). When designating a 50% reduction in stone volume as the threshold indicating high efficiency, the significant predictors of an efficient popcorn technique were a long pulse (OR 2.7, 95% CI 1.05–7.15), a longer duration (OR 11.4, 95% CI 3.88–33.29), a small (273 μm) laser fiber (OR 0.23, 95% CI 0.08–0.70) and higher power (W) (OR 1.14, 95% CI 1.09–1.20). Conclusions Higher energy, a longer pulse, frequencies higher than 10 Hz, a longer duration and a smaller laser fiber predict a popcorn technique that is more efficient at reducing stone volume. [ABSTRACT FROM AUTHOR]

Background: Dentin hypersensitivity treatments are based on the physical obliteration of the dentinal tubules to reduce hydraulic conductance. The aim of the present study is to evaluate the hydraulic conductance of bovine root dentin after irradiation with a 980-nm diode laser, with or without associated fluoride varnish.Methods: Sixty bovine root dentin specimens were divided into six groups (n = 10 in each group): G1, G3, and G5 (0.5 W, 0.7 W, and 1 W diode laser, respectively); G2, G4, and G6 (fluoride varnish application + 0.5 W, 0.7 W, and 1 W diode laser, respectively). The dentin hydraulic conductance was evaluated at four time periods with a fluxmeter: 1) with smear layer, 2) after 37% phosphoric acid etching, 3) after the treatments, and 4) after 6% citric acid challenge. After the dentinal fluid flow measurements, specimens were also evaluated for mineral composition using energy dispersive X-ray spectroscopy (EDS).Results: Analysis demonstrated a better result with increased irradiation power (P < 0.001), especially if the diode laser irradiation was associated with the application of fluoride varnish (P < 0.001), ensuring a greater reduction in permeability. Considering the groups treated only with laser irradiation, the 1 W group was superior when compared with the 0.5 W and 0.7 W irradiated groups immediately after treatment (P < 0.001). After citric acid testing, all groups showed similar results, except when comparing the 1 W groups with the 0.5 W groups (P = 0.04). EDS results of the irradiated groups showed an increase in the proportion of calcium and phosphorus ions, which demonstrates a superficial composition modification after laser treatments.Conclusion: Laser irradiation of exposed dentin promoted significant reduction in the dentin hydraulic conductance, mainly with higher energy densities and association with fluoride varnish. [ABSTRACT FROM AUTHOR]

Boswellia is a genus of shrubs or small/medium trees in which there is continued interest in a number of species for their potential medicinal use.. This review aimed to produce a 'map' of research on Boswellia to identify the potential for translation of research findings across different areas and identify any research gaps. Searches were carried out using major databases for in vitro, in vivo and clinical studies on any condition or disease, involving Boswellia species and extracts. Data were extracted on the health condition or disease, study type, Boswellia species and form being investigated. 5296 records were retrieved resulting in 657 relevant research papers; 297 (45.2%) reported in vitro studies, 236 (40.0%) reported in vivo studies, and 68 (10.3%) reported clinical studies. Studies were located corresponding to 20 of 21 health research categories, the most frequently researched being Cancer and Neoplasms, Inflammatory and Immune System, and Infection. The species Boswellia serrata and Boswellia sacra have undergone most investigation. Different forms of Boswellia were employed with boswellic acids, specifically Acetyl-11-keto-β-Boswellic acid (AKBA) and 11-Keto-β-Boswellic acid (KBA) generating most interest. Significant numbers of animal studies were located but few clinical studies. The extent, range and nature of the research on extracts and products derived from Boswellia species is revealed. Research is highlighted which may have more widely applicable results (for example on pharmacokinetics, delivery and toxicity), as are current research gaps and potential targets for greater collation of existing data to reduce duplication. [ABSTRACT FROM AUTHOR]

Background Success or failure of a composite restoration largely depends on its bonding to enamel/dentine. Several better adhesive systems have been developed during the last few years due to rapid advancement in the technology. Recent self-etched adhesives have fewer clinical steps and are less technique sensitive. Methods Ninety extracted human permanent molars were collected, grounded and finished to prepare flat dentine-bonding surfaces on their occlusal surface. All specimens were divided into three groups ( n = 30) on the basis of three adhesive systems Adper Easy Bond (AE), Beautibond (BB) and Xeno IV (XE). These adhesive systems were applied on prepared mid-dentine-bonding surface. A restorative resin was added with the help of a transparent tube of 2 mm height and 1.7 mm internal diameter and cured. Fifteen specimens in each group were loaded to failure in an Instron Universal Testing Machine after storage for 24 h at 37 °C to check micro-shear bond strength. Another fifteen specimens from each group were thermocycled 500 times at 5 °C and 55 °C with dwell time of 1 min in each bath followed by loading to failure. The data obtained was analyzed with SPSS version 21 at significance level of <05. Results After 24 h, micro-shear bond strength of BB was higher (26.04 MPa) than XE (23.69 MPa) and AE (21.50 MPa). After thermocycling, micro-shear bond strength decreased significantly in BB ( P = .001) and XE ( P = .03). Conclusion The micro-shear bond strength of BB was highest among three groups, which decreased after thermocycling. [ABSTRACT FROM AUTHOR]

Methods of investigating the digestibility of horse feeds have focused on the hindgut fermentation of feedstuffs, neglecting the foregut digestibility. The aim of this study was to evaluate the foregut digestibility and hindgut fermentation of barley in vitro. Three forms of barley (untreated (UB), micronised (MB)and torrefied (TB)) were evaluated. Substrates were ground to 2-mm and weighed into polyester bags (ANKOM R1020). Three replicates of 5 g (DM) per substrate were weighed into large bags (10 × 20 cm) while 4 replicates of 1g (DM) per substrate were weighed into smaller bags (4 × 10 cm). An in vitro simulated foregut digestion was set up as follows: one beaker containing artificial saliva (2.86 g/L NaCl, 1.5 g/L KHCO 3 , 2.77 g/L NaHCO 3 at pH 8.6), one with artificial gastric juice (2g/L pepsin, 1L 0.075M HCl, 10g/L Bioacidophilus powder at pH 3) and one with artificial pancreatic juice (2g/L pepsin, 1L 0.075M HCl, 85 mL/L pancreatic solution at pH 7 (45 PancrexV capsules/200 mL H 2 O)). All bags were incubated for 3h10min at 38°C: first suspended for 10min in artificial saliva, 2 h in artificial gastric juice and 1h in artificial pancreatic juice. At this point the large bags were rinsed in water and oven-dried for 24h at 60°C to determine foregut DM loss (F-DMd). Small bags were incubated for a further 72h within culture bottles with a digestion medium and equine fecal inoculum. After fermentation, suspension pH was measured, and bags oven-dried to calculate total DM loss (T-DMd). A one-way ANOVA analysis was conducted on MinitabⓇ 2019 to determine substrate effect on F-DMd, T-DMd and pH; significance level was set at P < 0.05 and Tukey post-hoc test used to define pairwise differences. The F-DMd was highest for TB, followed by MB, with UB being lowest (P < 0.001), while T-DMd was highest for MB compared with UB (P < 0.05); pH after fermentation was lower for UB in comparison with TB (P < 0.01). These findings suggest that both micronisation and torrefaction improve the in vitro foregut digestibility of barley; however, the greatest effect was seen with torrefaction. [ABSTRACT FROM AUTHOR]