2,393 research outputs found
The effect of chlorhexidine primer application on the clinical performance of composite restorations: a literature review
AbstractTo discuss the effectiveness of chlorhexidine (CHX) used as therapeutic dentin primer in adhesively bonded composite restorations.OverviewAn electronic search in MEDLINE database, accessed through PubMed was conducted. No restrictions of languages and date of publication were made. The following key words were used: "chlorhexidine", "composite" and "composite resins." Clinical studies in which CHX was used during bonding procedures were included in this review. Six studies met the inclusion criteria. Of these, five studies were carried out on noncarious cervical lesions (NCCL). Only one study was carried out on class II preparation of permanent molars. In all studies, either etchâandârinse and selfâetch adhesive systems were used during bonding procedures. On the basis of the reviewed clinical trials, it can be concluded that CHX primer application does not seem to influence clinical outcome of composite restorations.Clinical significanceCurrent scientific evidence cannot neither strongly recommend nor discourage the application of CHX as therapeutic primer in composite restorations. Studies with longer followâup periods with adhesive restorations placed on dentin after caries removal, rather than only on NCCL, are desirable to further investigate the therapeutic effect of CHX during bonding procedures
Relationship between microstructure, mechanical and magnetic properties of pure iron produced by laser powder bed fusion (L-PBF) in the as-built and stress relieved conditions
In the present work, the mechanical and magnetic properties of pure iron manufactured by laser-powder bed fusion (L-PBF) were investigated both in the as-built (AB) and stress relieved (HT) conditions, with the aim of elucidating their relationship with the microstructure and evaluating whether and to what extent it can be suitable for industrial applications. The L-PBF process was optimized to obtain high density, crack-free components. Specimens for microstructural analyses, tensile and magnetic tests were manufactured under the optimized conditions and tested both in the as-built and annealed (850 degrees C for 1 h, to relieve the residual stresses) conditions. Tensile tests showed high tensile strength in both AB and HT conditions (larger than those of conventionally produced pure iron), with higher ductility and lower strength after stress relieving. The magnetic study indicated a not optimal magnetic softness although the heat treatment enhanced the permeability and reduced the coercivity with respect to the as-built condition. The high mechanical strength and low magnetic softness came from the very fine grain size (about 5 mu m) of L-PBF pure iron. Instead, the improvement of magnetic softness and ductility after heat treatment was attributed to the possible reduction of dislocation density and consequent stress relief. The results indicated the possibility to achieve a considerably high mechanical strength, in pure iron manufactured by L-PBF, although the fine grain size limits its magnetic softness
Novel Multifunctional Magnetic Inorganic Composites: Synthesis and Characterization
We report the preparation of a series of new magnetic inorganic composites (MICs) with tuneable magnetic and mechanical properties. In the field of power inductive components and inductive heating, they could transfer energy with high robustness and excellent performances. Moreover, they may mitigate electromagnetic interference (EMI) in the LF and MF band. The MICs have been prepared using an alkaline or acidic activation process carried out in the presence of commercial magnetic micrometric particles made of anisotropic and isotropic Sr-ferrite. Three different matrices have been prepared, varying the type of activator, slag addition, water content, and aggregates
Novel Multifunctional Magnetic Inorganic Composites: Synthesis and Characterization
We report the preparation of a series of new magnetic inorganic composites (MICs) with tuneable magnetic and mechanical properties. In the field of power inductive components and inductive heating, they could transfer energy with high robustness and excellent performances. Moreover, they may mitigate electromagnetic interference (EMI) in the LF and MF band. The MICs have been prepared using an alkaline or acidic activation process carried out in the presence of commercial magnetic micrometric particles made of anisotropic and isotropic Sr-ferrite. Three different matrices have been prepared, varying the type of activator, slag addition, water content, and aggregates
Resin composite cements: Current status and a novel classification proposal
ObjectivesCurrently, a classification of resin cements that includes relatively recently formulated ("universal") cements is lacking. Furthermore, the terminology used to define different resin cements in the scientific reports is inconsistent. Accordingly, this work aims to: (i) propose a novel classification of resin composite cements; (ii) disambiguate the term "universal cements" and (iii) present an overview of the properties of these cements. MethodsAn analysis of peer-reviewed literature (PubMed search), as well as market research on definitive resin composite cements were performed. ResultsA tendency toward simplified and versatile luting materials was observed both in the scientific literature and on the dental market with the advent of self-adhesive/one-step resin cements. However, additional priming procedures were necessary to improve their bonding performance in certain clinical situations. Hence, several cements that can be applied both in adhesive and self-adhesive mode were introduced. These cements are associated with a universal adhesive resin, that can be used as a tooth and/or restorative material primer, without the need for other priming systems, regardless of the substrate. These systems should be considered truly universal. Therefore, we hereby suggested a new classification of resin-based cements: (1) adhesive/multi-step; (2) self-adhesive/one-step; (3) universal cements (one- or multi-step). Despite promising in vitro results, clinical trials and long-track laboratory studies are necessary to confirm the reliability of the universal cements. ConclusionsThis review presented the current advances in the field of resin-based cements, which are reflected in the proposed classification. The term "universal cement" was disambiguated, which will help standardize the terminology used in published research. Clinical SignificanceThe classification of resin-based cements and a better understanding of the proper terminology will help standardize the terminology in published research, as well as improve the understanding of the clinical practitioners of the different indications and possible modalities of use of the available cements
Selective adhesive luting: A novel technique for improving adhesion achieved by universal resin cements
Objective: We aimed to introduce the concept of "Selective adhesive luting-SAL" which is explained through clinical steps and supported by preliminary laboratory evidence. Clinical considerations: Cementation with rubber dam is difficult to perform in case of short abutment teeth and/or subgingival crown margins. By means of universal resin cements/universal adhesive systems, which can be employed in self-adhesive as well as adhesive luting procedures, this paper presents a novel technique allowing clinicians to perform reliable cementation where rubber dam isolation is difficult. The SAL technique entails the application of a universal adhesive system only on easily accessible abutment surfaces, enabling simultaneous adhesive and self-adhesive luting in different portions of the abutment. The SAL clinical workflow is explained through prosthodontic rehabilitation of maxillary right central incisor affected by microdontia and restored with a lithium-disilicate crown. Furthermore, our laboratory microshear bond strength study supports the rationale behind SAL application demonstrating higher bond strength even when the adhesive resin is placed only on one portion of the cementation substrate. Clinical significance: This article advocates the application of SAL technique in clinical situations where effective adhesive luting is uncertain, since it can improve the adhesion between the tooth and universal resin cements
Effects of Microencapsulated Ferulic Acid or Its Prodrug Methyl Ferulate on Neuroinflammation Induced by Muramyl Dipeptide
Ferulic acid (Fer) is known for its antioxidant and anti-inflammatory activities, which are possibly useful against neurodegenerative diseases. Despite the ability of Fer to permeate the brain, its fast elimination from the body does not allow its therapeutic use to be optimized. The present study proposes the preparation and characterization of tristearin- or stearic acid-based solid lipid microparticles (SLMs) as sustained delivery and targeting systems for Fer. The microparticles were produced by conventional hot emulsion techniques. The synthesis of the methyl ester of
Fer (Fer-Me) allowed its encapsulation in the SLMs to increase. Fer-Me was hydrolyzed to Fer in rat whole blood and liver homogenate, evidencing its prodrug behavior. Furthermore, Fer-Me displayed antioxidant and anti-inflammatory properties. The amount of encapsulated Fer-Me was 0.719 +/- 0.005% or 1.507 +/- 0.014% in tristearin or stearic acid SLMs, respectively. The tristearin SLMs were able to control the prodrug release, while the stearic acid SLMs induced a significant increase of its dissolution rate in water. Jointly, the present results suggest that the tristearin SLMs loaded with Fer-Me could be a potential formulation against peripheral neuropathic pain; conversely, the stearic acid SLMs could be useful for Fer-Me uptake in the brain after nasal administration of the formulation
What is the role of physical exercise in the era of cancer prehabilitation? A systematic review
Purpose: Exercise before surgery, as part of prehabilitation, aiming to enhance patients' functional and physiological capacity, has become widespread, necessitating an in-depth understanding. Methods: A systematic search was conducted on Pubmed, Cochrane, and Scopus to examine the effect of exercise as prehabilitation, alone or in combination with other interventions, in patients with cancer. Interventional studies applying a single-arm, randomized controlled, or nonrandomized design were included. Results: A total of 97 studies were included, and categorized according to cancer types, i.e., gynecological, breast, urological, gastrointestinal and lung cancer. For each cancer site, the effect of exercise, on physical fitness parameters and postoperative outcomes, including length of hospital stay and postoperative complications, was reported. Conclusion: Exercise as prehabilitation may have an important role in improving physical fitness, postoperative outcomes, and accelerating recovery, especially in certain types of malignancies
Local Structure and Magnetism of Fe2O3 Maghemite Nanocrystals: The Role of Crystal Dimension
Here we report on the impact of reducing the crystalline size on the structural and magnetic properties of Îł-Fe2O3 maghemite nanoparticles. A set of polycrystalline specimens with crystallite size ranging from ~2 to ~50 nm was obtained combining microwave plasma synthesis and commercial samples. Crystallite size was derived by electron microscopy and synchrotron powder diffraction, which was used also to investigate the crystallographic structure. The local atomic structure was inquired combining pair distribution function (PDF) and X-ray absorption spectroscopy (XAS). PDF revealed that reducing the crystal dimension induces the depletion of the amount of Fe tetrahedral sites. XAS confirmed significant bond distance expansion and a loose Fe-Fe connectivity between octahedral and tetrahedral sites. Molecular dynamics revealed important surface effects, whose implementation in PDF reproduces the first shells of experimental curves. The structural disorder affects the magnetic properties more and more with decreasing the nanoparticle size. In particular, the saturation magnetization reduces, revealing a spin canting effect. Moreover, a large effective magnetic anisotropy is measured at low temperature together with an exchange bias effect, a behavior that we related to the existence of a highly disordered glassy magnetic phase
Exploring the Association between Health-Related Physical Fitness and Quality of Life in Patients with Cancer: A Cross-Sectional Study
Whereas an exercise intervention effectively improves patients' quality of life, little information is available about the contribution of each physical fitness component. This study aims to explore the association between physical fitness components and the quality-of-life domain in patients with cancer. Between September 2021 and August 2023, 160 patients with mixed cancer types visiting the Oncology Unit were selected on a consecutive basis according to selection criteria. They underwent a comprehensive baseline assessment including the six-minute walking test, the handgrip strength test, the isometric leg press test, the back scratch, sit and reach tests, their waist-hip ratio, and their body mass index. The European Organization for Research and Treatment of Cancer Quality of Life and Core Questionnaire was used to measure the quality of life. The sample size was based on the use of regression models to study associations between clinical characteristics and fitness outcomes. All of the analyses were performed using the SPSS v.25 statistical package. Patients had a mean age of 58 years, 68% were female, 42% were affected by breast cancer, and all were receiving anticancer treatments. Higher functional capacity was associated with better global health status (p < 0.0001) and physical (p < 0.0001), role (p < 0.0001), emotional (p = 0.026), and social function (p = 0.016) and inversely linked with fatigue (p = 0.001). Lower-limb flexibility was significantly associated with all of the domains except for role and social functions. The waist-hip ratio was inversely associated with physical function (p < 0.0001) and positively related to fatigue (p = 0.037). Exercise programs aiming to improve the quality of life in cancer should be addressed to optimize these fitness components
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