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The resin-modified glass ionomer materials are hybrid materials of traditional glass ionomer cement with a small addition of light-curing resin, and hence exhibit properties intermediate to the two, with some characteristics superior to conventional glass ionomer materials. Generally, they have the advantages of both such as adhesion to tooth structure, esthetics, fluoride release and rapid hardening by visible light. Issues surrounding other physical properties, such as the mechanism of adhesion, sensitivity to water, long-term wear and strength, need to be addressed and substantiated. There are other considerations, which are not features of the conventional materials, but are of importance with the resin-modified glass ionomer cements i.e. light-curing, which require further research to provide evidence of their behavior. The future for this group of materials is unknown, but the currently available materials appear to be promising.

Since their introduction in the market, some 30 yrs ago, the biocompatibility aspects of glass-ionomer cements (GICs) have been intensively studied. In general, cytotoxicity of fully set conventional preparations in previous studies was shown to be minimal. However, a resin-modified preparation proved to be cytotoxic under these conditions. This product was also observed to be mutagenic, but data in this area are sparse and difficult to interpret. There is also evidence that certain GICs exert some antibacterial properties which is claimed to be related to the fluoride release; however, the mechanisms for this fluoride release are still unclear. Pulp response studies have shown conflicting results. However, unfavorable initial reactions, if present, resolved with time if a bacterial layer under the restoration and pulp exposures were prevented. Pain reactions after cementation of cast restorations with GICs have been reported in the past but there are no such reports in the more recent literature.

Most dental materials permit of microleakage because oral fluids and bacteria commonly gain access to dentin surfaces. Dentin is permeable and allows the bidirectional movement of materials from the oral cavity, across dentin to the pulp and vice versa. The pupal irritation associated with microleakage is often dictated by the permeability of dentin. Thick dentin covered with a smear layer is a better barrier than thin dentin with the smear layer removed, while coronal dentin is more permeable than root dentin. Carious dentin is less permeable than normal dentin, but freshly cut dentin is more permeable than previously prepared dentin. This is partly due to the movement of large plasma proteins from the pulpal blood vessels into dentin. The pulpal circulation contributes to the health of the pulp by supplying nutrients and by removing toxic material that diffuses across dentin via the microcirculation. Thus, there is a delicate balance involving the rate bacterial products diffuse around microgaps between restorative materials and dentin, the rate these materials permeate across dentin and the rate they are removed during pulpal circulation.

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The growing use of NiTi rotary instruments in dental practice demands a good understanding of their concept of alloy and design in relation to improved properties and inherent limitations. Nickel titanium's super elasticity allows more centered canal preparations with less transportation and a decreased incidence of canal aberrations. Furthermore, the production of files with increased taper became possible. This is of special importance because of concerns on the achievement of adequate irrigation and close adaptation of the filling material during endodontic treatment. Unique shaft and tip designs should permit the use of a rotary handpiece allowing different tactile awareness. On the other hand, special attention is paid to maximize cutting efficiency and cutting control throughout instrumentation. NiTi rotary instruments are generally used in a crown-down approach and a continuous reaming motion. Consequently, rounder root canal preparations, with less straightening and a smaller amount of apical extrusion is achievable. In spite of their increased flexibility, separation is still a concern with NiTi files. The phenomenon of repeated cyclic metal fatigue and the variable of torsional loading are two important factors in instrument fracture. However, with awareness of the appropriate manipulation and special attention to the equipment used, NiTi systems are safe with a minimal incidence of instrument failure.

The search for a material to replace amalgam continues as a major quest in materials science. Resin composites may offer one solution but an alternative class of material, the glass ionomer cements (GICs) may have some potential for fulfilling this role. GICs were first introduced to the dental profession in 1976, and have now become an accepted part of the dental armamentarium, especially for use in low load bearing situations. They possess a low coefficient of thermal expansion similar to that of tooth structure, physicochemical bonding to both enamel and dentin, and the release of fluoride ions into the adjacent tooth tissue. These properties help to reduce marginal leakage and may contribute to a reduced incidence of recurrent decay in the restored tooth. Fluoride released into the ambient fluids has a caries-preventive effect in neighboring teeth by enhancing remineralization and inhibiting demineralization of the dental hard tissues. The main criticisms of the GICs are their brittleness, poor surface polish, porosity and surface wear. To overcome some of these deficiencies, considerable attention has been directed at improving their physical properties, especially with the addition of metal powders, the metal-modified GICs. Different metal powders have been tried, including alloys of silver and tin, pure silver, gold, titanium, palladium and stainless steel. There is conflicting data as to whether or not these materials are sufficiently strong for use in high stress restorations, especially their potential use as replacement materials for amalgam fillings.

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PURPOSE: This overview presents a description of organofunctional trialkoxysilane coupling agents (silanes), their chemistry, properties, use, and some of the main clinical experiences in dentistry. MATERIALS AND METHODS: The main emphasis was on major dental journals that have been reviewed from 1958 up to the latest research news from 2002. A MEDLINE search with the key words "dental silanes" was used. Special silane literature and journals outside dentistry were also cited. RESULTS: The main emphasis is on the use of silanes in prosthetic and restorative dentistry. Clinical relevance was based mainly on either short- or long-term tests. The interpretation of various results is not given, mainly because of controversial observations that may be very difficult to explain. Nevertheless, the majority of the clinical results pointed to silanes playing a significant role in the adhesion process. Silane reaction mechanisms were not entirely understood, and there exist several theories for bonding mechanisms for silanes and substrates. CONCLUSION: Dental materials offer a continuously challenging forum for silanes, and silanes will play an essential role in material development.

This study examines the social media uptake of scientific journals on two different platforms - X and WeChat - by comparing the adoption of X among journals indexed in the Science Citation Index-Expanded (SCIE) with the adoption of WeChat among journals indexed in the Chinese Science Citation Database (CSCD). The findings reveal substantial differences in platform adoption and user engagement, shaped by local contexts. While only 22.7% of SCIE journals maintain an X account, 84.4% of CSCD journals have a WeChat official account. Journals in Life Sciences & Biomedicine lead in uptake on both platforms, whereas those in Technology and Physical Sciences show high WeChat uptake but comparatively lower presence on X. User engagement on both platforms is dominated by low-effort interactions rather than more conversational behaviors. Correlation analyses indicate weak-to-moderate relationships between bibliometric indicators and social media metrics, confirming that online engagement reflects a distinct dimension of journal impact, whether on an international or a local platform. These findings underscore the need for broader social media metric frameworks that incorporate locally dom

This paper introduces the Unique Citing Documents Journal Impact Factor(Uniq-JIF) as a supplement to the traditional Journal Impact Factor(JIF). The Uniq-JIF counts each citing document only once, aiming to reduce the effects of citation manipulations. Analysis of 2023 Journal Citation Reports data shows that for most journals, the Uniq-JIF is less than 20% lower than the JIF, though some journals show a drop of over 75%. The Uniq-JIF also highlights significant reductions for journals suppressed due to citation issues, indicating its effectiveness in identifying problematic journals. The Uniq-JIF offers a more nuanced view of a journal's influence and can help reveal journals needing further scrutiny.

We compare the network of aggregated journal-journal citation relations provided by the Journal Citation Reports (JCR) 2012 of the Science and Social Science Citation Indexes (SCI and SSCI) with similar data based on Scopus 2012. First, global maps were developed for the two sets separately; sets of documents can then be compared using overlays to both maps. Using fuzzy-string matching and ISSN numbers, we were able to match 10,524 journal names between the two sets; that is, 96.4% of the 10,936 journals contained in JCR or 51.2% of the 20,554 journals covered by Scopus. Network analysis was then pursued on the set of journals shared between the two databases and the two sets of unique journals. Citations among the shared journals are more comprehensively covered in JCR than Scopus, so the network in JCR is denser and more connected than in Scopus. The ranking of shared journals in terms of indegree (that is, numbers of citing journals) or total citations is similar in both databases overall (Spearman's \r{ho} > 0.97), but some individual journals rank very differently. Journals that are unique to Scopus seem to be less important--they are citing shared journals rather than bein

The journal structure in the China Scientific and Technical Papers and Citations Database (CSTPCD) is analysed from three perspectives: the database level, the specialty level and the institutional level (i.e., university journals versus journals issued by the Chinese Academy of Sciences). The results are compared with those for (Chinese) journals included in the Science Citation Index. The frequency of journal-journal citation relations in the CSTPCD is an order of magnitude lower than in the SCI. Chinese journals, especially high-quality journals, prefer to cite international journals rather than domestic ones. However, Chinese journals do not get an equivalent reception from their international counterparts. The international visibility of Chinese journals is low, but varies among fields of science. Journals of the Chinese Academy of Sciences (CAS) have a better reception in the international scientific community than university journals.

This study examines the role of top-tier conference publications in Hungarian computer science research. We show that the national scientometric practice, which is currently journal-oriented, diverges from international norms, creating incentive distortions in researcher evaluation. By linking multiple databases (iCore, DBLP, MTMT, MTA-ATT), we mapped Hungarian-affiliated CORE A* and A conference papers, their temporal and thematic distribution, and author trajectories. Our results indicate that, in theoretical fields, publishing at international conferences became common earlier than in applied fields. At the same time, in applied fields, successful researchers are more likely to continue their careers in foreign institutions or in industry positions. Overall, a substantial share of the already established, internationally most successful researchers are now affiliated with institutions abroad. We recommend recognizing CORE A* papers as equivalent to D1 and CORE A papers as equivalent to Q1 journals in national evaluation systems.

DESIDOC Journal of Library & Information Technology (DJLIT) formerly known as DESIDOC Bulletin of Information Technology is a peer-reviewed, open access, bimonthly journal. This paper presents a Scientometric analysis of the DESIDOC Journal. The paper analyses the pattern of growth of the research output published in the journal, pattern of authorship, author productivity, and, subjects covered to the papers over the period (2013-2017). It is found that 227 papers were published during the period of study (2001-2012). The maximum numbers of articles were collaborative in nature. The subject concentration of the journal noted is Scientometrics. The maximum numbers of articles (65%) have ranged their thought contents between 6 and 10 pages. The study applied standard formula and statistical tools to bring out the factual result.

This study aims to present a scientometric analysis of the journal titled Cognition for a period of 20 years from 1999 to 2018. The present study was conducted with an aim to provide a summary of research activity in current journal and characterize its most aspects. The research coverage includes the year wise distribution of articles, authors, institutions, countries and citation analysis of the journal. The analysis showed that 2870 papers were published in journal of Cognition from 1999 to 2018. The study identified top 20 prolific authors, institutions and countries of the journal. Researchers from USA have been made the most percentage of contributions.