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The portland cement (PC) industry is responsible for approximately 7% of all carbon dioxide (CO2) emissions in the world. Blast furnace slag (BFS) has been increasingly used as a substitute for PC, due to the efficient disposal of steel industry waste and reductions in CO2 emissions. The present work investigated the environmental benefits of cementitious materials with large volumes of BFS (up to 90% PC replacement for the S90 mixture) and the influence on porosity and compressive strength. By X-ray computed microtomography and mercury intrusion porosimetry, pore size distribution was assessed. Porosity was also evaluated by water absorption. The environmental impacts were investigated by analyzing the embodied CO2 emissions (ECO2) and embodied energy (EE) by using life cycle assessment methodology. Reductions of around 40% in the compressive strength of S90 were found, while reductions in EE and ECO2 were above 80%. The S90 showed higher porosity at the age of 28 days, but then promoted a more active pore closing effect over time, being nevertheless feasible for use in terms of porosity. The use of S90 is expected to increase durability due to its thinner porous matrix, and contribute to reducing environmental impact and advancing cleaner production. Practical Applications: Today, there is a global call to action to end poverty, protect the environment and climate, and ensure that people everywhere can enjoy peace and prosperity. Objectives set for the United Nations aim to help developing countries, like Brazil, achieve the 2030 Agenda for Sustainable Development. A highlight is given to "Sustainable Development Goal 9: Industry, Innovation and Infrastructure" (SDG 9), which aims to build resilient infrastructure, promote inclusive and sustainable industrialization, and foster innovation. The portland cement (PC) industry is responsible for approximately 7% of all carbon dioxide (CO2) emissions in the world. The study carried out here points to the feasibility of using blast furnace slag (BFS) to replace up to 90% of PC clinker, and demonstrates the environmental advantages in terms of reducing CO2 emissions and energy consumption. In this context, the use of clinkers with higher concentrations of BFS, up to 90%, has emerged as a way to contribute to the sustainable development proposed by SDG 9. [ABSTRACT FROM AUTHOR]

Background: Silver diamine fluoride has attracted attention because of its clinical success in arresting dental caries. Thus, the aim of this study was to evaluate the effect of different application times and concentrations of silver diamine fluoride (SDF) on deciduous tooth enamel remineralization., Material and Methods: Blocks of deciduous tooth enamel were categorized into six groups of 11 each: 2 control groups: intact enamel, and demineralized enamel; 38% SDF and 30% SDF which were subdivided according to application times (1 and 3 min). The microhardness of samples was determined, and all groups except the intact enamel group were subjected to pH cycling to produce initial carious lesions. The 38% and 30% SDF solutions were applied to the enamel for 1 or 3 min. After pH cycling and SDF treatments, the microhardness was again determined. Samples were sectioned to evaluate the cross-sectional microhardness. Furthermore, internal porosity of the samples was examined using micro-CT. Data were statistically analyzed by analysis of variance followed by Tukey's test, and linear regression analyses were performed., Results: There was no difference in enamel remineralization based on surface and cross-sectional microhardness. The 30% SDF solution applied for 3 min promoted significantly less pores than the other groups., Conclusions: The 1-min application time promoted enamel remineralization regardless of the SDF concentration (30% or 38%). Key words: Cariostatic agents, dental caries, primary tooth, tooth remineralization., Competing Interests: Conflicts of interest No potential conflict of interest relevant to this article was reported., (Copyright: © 2021 Medicina Oral S.L.)