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The aim of direct pulp capping (DPC) is to promote pulp healing and mineralized tissue barrier formation by placing a dental biomaterial directly over the exposed pulp. Successful application of this approach avoids the need for further and more extensive treatment. In order to ensure a complete pulp healing with the placement of restorative materials, a mineralized tissue barrier must form to protect the pulp from mi-crobial invasion. The formation of mineralized tissue barrier can only be induced when there is a significant reduction in pulp inflammation and infection. Consequently, promoting the healing of pulp inflammation may provide a favorable therapeutic opportunity to maintain the sustainability of DPC treatment. Mineralized tissue formation was observed as the favorable reaction of exposed pulp tissue against a variety of dental biomaterials utilized for DPC. This observation reveals an intrinsic capacity of pulp tissue for healing. Therefore, this review focuses on the DPC and its healing procedure as well as the materials used for DPC treatment and their mechanisms of action to promote pulpal healing. In addition, the factors that can affect the healing process of DPC, clinical considerations and future perspective has been described.(c) 2023 The Authors. Published by Elsevier Ltd on behalf of The Japanese Association for Dental Science. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/license/by-ac-nd/4.0/).

Due to the high failure rates associated to endodontic disinfection, this study aimed to investigate the antibacterial properties of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with Ca(OH)2 for endodontic disinfection procedures. Ca(OH)2 NPs production and physicochemical characterization were carried out as well as multiple antibacterial tests using three bacterial strains and an ex vivo model of endodontic infection with extracted human teeth. Agar diffusion test and broth dilution determined the inhibition growth zones (n = 5) and the minimal inhibitory concentration (MIC, n = 5), respectively. Cell viability was assessed using Live/Dead staining with confocal microscopy (n = 5). Data was analysed using ANOVA followed by post-hoc analysis. After 24 h of incubation, Ca(OH)₂ NPs demonstrated a MIC of 10 µg/mL for Porphyromonas gingivalis (p < 0.001) and Enterococcus faecalis and 5 µg/mL for Fusobacterium nucleatum (p < 0.001). Although the agar diffusion test did not exhibit any inhibition area for Ca(OH)2 nor for Ca(OH)₂ NPs, this was probably due to the buffering effect of the agar medium. However, the antibacterial capacity was confirmed in an ex vivo model, where instrumentalized teeth were infected with Enterococcus Faecalis and treated after 28 days of culture. A significant reduction in bacterial metabolic activity was confirmed for Ca(OH)2 NPs (40 % reduction with a single dose) and confirmed by Live/Dead staining. In conclusion, Ca(OH)₂-loaded PLGA NPs present promising antibacterial efficacy for endodontic disinfection procedures.

The aim of direct pulp capping (DPC) is to promote pulp healing and mineralized tissue barrier formation by placing a dental biomaterial directly over the exposed pulp. Successful application of this approach avoids the need for further and more extensive treatment. In order to ensure a complete pulp healing with the placement of restorative materials, a mineralized tissue barrier must form to protect the pulp from mi-crobial invasion. The formation of mineralized tissue barrier can only be induced when there is a significant reduction in pulp inflammation and infection. Consequently, promoting the healing of pulp inflammation may provide a favorable therapeutic opportunity to maintain the sustainability of DPC treatment. Mineralized tissue formation was observed as the favorable reaction of exposed pulp tissue against a variety of dental biomaterials utilized for DPC. This observation reveals an intrinsic capacity of pulp tissue for healing. Therefore, this review focuses on the DPC and its healing procedure as well as the materials used for DPC treatment and their mechanisms of action to promote pulpal healing. In addition, the factors that can affect the healing process of DPC, clinical considerations and future perspective has been described.(c) 2023 The Authors. Published by Elsevier Ltd on behalf of The Japanese Association for Dental Science. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/license/by-ac-nd/4.0/).

The aim of direct pulp capping (DPC) is to promote pulp healing and mineralized tissue barrier formation by placing a dental biomaterial directly over the exposed pulp. Successful application of this approach avoids the need for further and more extensive treatment. In order to ensure a complete pulp healing with the placement of restorative materials, a mineralized tissue barrier must form to protect the pulp from mi-crobial invasion. The formation of mineralized tissue barrier can only be induced when there is a significant reduction in pulp inflammation and infection. Consequently, promoting the healing of pulp inflammation may provide a favorable therapeutic opportunity to maintain the sustainability of DPC treatment. Mineralized tissue formation was observed as the favorable reaction of exposed pulp tissue against a variety of dental biomaterials utilized for DPC. This observation reveals an intrinsic capacity of pulp tissue for healing. Therefore, this review focuses on the DPC and its healing procedure as well as the materials used for DPC treatment and their mechanisms of action to promote pulpal healing. In addition, the factors that can affect the healing process of DPC, clinical considerations and future perspective has been described.(c) 2023 The Authors. Published by Elsevier Ltd on behalf of The Japanese Association for Dental Science. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/license/by-ac-nd/4.0/).

The widespread use of renewable energy requires the support of high-capacity energy storage systems. This work proposes a thermochemical energy storage system for concentrated solar power plants based on the reversible hydration/dehydration process of the calcium hydroxide. It is a single fluidised bed reactor concept with alternating dehydration-hydration processes, charging and discharging alternating reactions, with superheated steam as fluidising agent. The system has been modelled using Aspen Plus™, including equilibrium data and hydrodynamic performance of the reactor. The model has been used to evaluate the effect of different parameters of the reactor, such as geometry, average particle size, or inlet streams conditions, on the performance of the reactor and the system. The thermal integration of the system was optimised using pinch analysis. For the proposed layouts, round-trip efficiencies values of 68 % are obtained. The economic analyses show specific investment costs between 4170 $/kWe and 3250 $/kWe for plants in the range of 31 MW to 45 MW, which are competitive with those expected for plants with storage of molten salts in this power range. LCOE values between 67 $/MWh and 83 $/MWh were obtained. The analyses show how these values highly depend on the fresh material replacement requirements related to the deactivation of the material and operational strategies. The results show the interest in further developments of this concept for concentrated solar power plants.

Arbetet studerade skillnaderna mellan en användning av kalciumhydroxid samtnatriumhydroxid som pH-reglerande kemikalie i en kemisk vattenreningsanläggning.Samt dess påverkan på filtreringssteg som sandfilter, aktivkol filtrering samt jonbytarfiltrering. Det behandlade hur reningsgraden påverkas sett till metallreduktion av;krom, nickel, koppar och zink. Hur slammängderna är i förhållande tillvarandramellan de olika pH-reglernade kemikalierna och slutligen hur filtreringsstegenpåverkas beroende på vilken pH-reglerande kemikalie som doserats. Resultatet förarbetet har visat på att reningsgraden minskar vid användning av natriumhydroxidsom pH-reglerande kemikalie vilket besvarar en del av syftet samt frågeställningenmed arbetet. Ytterligare har resultatet påvisat att de efterkommande filtreringsstegensom i en eventuell framtid kan implementeras leder till en reducering avmetallhalterna i vattnet, vanligen gick reduceringen inte att statistiskt säkerställa mentendenser på en reducering påvisades. Även de erhållna slammängdernareducerades vid användning av natriumhydroxid som pH-reglerande kemikalie vilketvar ett förväntat resultat sett till hypotes och litteratur. Ytterligare minskadeturbiditeten för klarfasproverna vid en natriumhydroxiddosering i förhållande till enkalciumhydroxiddosering. Arbetets resultat har således påvisat den goda möjlighetenatt ersätta den manuella doseringen av solid kalciumhydroxid som pH-reglerandekemikalie emot en automatisk dosering av natriumhydroxid erhållen i vätskeform., This work studied the differences between the use of calcium hydroxide and sodiumhydroxide as a pH-regulating chemical in a chemical water treatment plant. As wellas its impact on filtration steps such as sand filter, activated carbon filtration and ionexchange filtration. It dealt with how the degree of purification is affected in terms ofmetal reduction of; chromium, nickel, copper and zinc. How the sludge amounts arein relation to each other between the different pH-regulated chemicals and finallyhow the filtration steps are affected depending on which pH-regulating chemical hasbeen dosed. The results for the work have shown that the degree of purificationdecreases when using sodium hydroxide as a pH-regulating chemical, whichanswers part of the purpose and the question of the work. Furthermore, the resultshave shown that the subsequent filtration steps that can be implemented in thepossible future lead to a reduction of the metal contents in the water, usually thereduction could not be statistically confirmed but tendencies of a reduction wereshown. The amounts of sludge obtained were also reduced by using sodiumhydroxide as a pH-regulating chemical, which was an expected result in terms ofhypothesis and literature. Furthermore, the turbidity of the clear phase samplesdecreased at a sodium hydroxide dosage relative to a calcium hydroxide dosage.The results of the work have thus demonstrated the good possibility of replacing themanual dosing of solid calcium hydroxide as a pH-regulating chemical with anautomatic dosing of sodium hydroxide obtained in liquid form.

The widespread use of renewable energy requires the support of high-capacity energy storage systems. This work proposes a thermochemical energy storage system for concentrated solar power plants based on the reversible hydration/dehydration process of the calcium hydroxide. It is a single fluidised bed reactor concept with alternating dehydration-hydration processes, charging and discharging alternating reactions, with superheated steam as fluidising agent. The system has been modelled using Aspen Plus™, including equilibrium data and hydrodynamic performance of the reactor. The model has been used to evaluate the effect of different parameters of the reactor, such as geometry, average particle size, or inlet streams conditions, on the performance of the reactor and the system. The thermal integration of the system was optimised using pinch analysis. For the proposed layouts, round-trip efficiencies values of 68 % are obtained. The economic analyses show specific investment costs between 4170 $/kWe and 3250 $/kWe for plants in the range of 31 MW to 45 MW, which are competitive with those expected for plants with storage of molten salts in this power range. LCOE values between 67 $/MWh and 83 $/MWh were obtained. The analyses show how these values highly depend on the fresh material replacement requirements related to the deactivation of the material and operational strategies. The results show the interest in further developments of this concept for concentrated solar power plants.

Arbetet studerade skillnaderna mellan en användning av kalciumhydroxid samtnatriumhydroxid som pH-reglerande kemikalie i en kemisk vattenreningsanläggning.Samt dess påverkan på filtreringssteg som sandfilter, aktivkol filtrering samt jonbytarfiltrering. Det behandlade hur reningsgraden påverkas sett till metallreduktion av;krom, nickel, koppar och zink. Hur slammängderna är i förhållande tillvarandramellan de olika pH-reglernade kemikalierna och slutligen hur filtreringsstegenpåverkas beroende på vilken pH-reglerande kemikalie som doserats. Resultatet förarbetet har visat på att reningsgraden minskar vid användning av natriumhydroxidsom pH-reglerande kemikalie vilket besvarar en del av syftet samt frågeställningenmed arbetet. Ytterligare har resultatet påvisat att de efterkommande filtreringsstegensom i en eventuell framtid kan implementeras leder till en reducering avmetallhalterna i vattnet, vanligen gick reduceringen inte att statistiskt säkerställa mentendenser på en reducering påvisades. Även de erhållna slammängdernareducerades vid användning av natriumhydroxid som pH-reglerande kemikalie vilketvar ett förväntat resultat sett till hypotes och litteratur. Ytterligare minskadeturbiditeten för klarfasproverna vid en natriumhydroxiddosering i förhållande till enkalciumhydroxiddosering. Arbetets resultat har således påvisat den goda möjlighetenatt ersätta den manuella doseringen av solid kalciumhydroxid som pH-reglerandekemikalie emot en automatisk dosering av natriumhydroxid erhållen i vätskeform., This work studied the differences between the use of calcium hydroxide and sodiumhydroxide as a pH-regulating chemical in a chemical water treatment plant. As wellas its impact on filtration steps such as sand filter, activated carbon filtration and ionexchange filtration. It dealt with how the degree of purification is affected in terms ofmetal reduction of; chromium, nickel, copper and zinc. How the sludge amounts arein relation to each other between the different pH-regulated chemicals and finallyhow the filtration steps are affected depending on which pH-regulating chemical hasbeen dosed. The results for the work have shown that the degree of purificationdecreases when using sodium hydroxide as a pH-regulating chemical, whichanswers part of the purpose and the question of the work. Furthermore, the resultshave shown that the subsequent filtration steps that can be implemented in thepossible future lead to a reduction of the metal contents in the water, usually thereduction could not be statistically confirmed but tendencies of a reduction wereshown. The amounts of sludge obtained were also reduced by using sodiumhydroxide as a pH-regulating chemical, which was an expected result in terms ofhypothesis and literature. Furthermore, the turbidity of the clear phase samplesdecreased at a sodium hydroxide dosage relative to a calcium hydroxide dosage.The results of the work have thus demonstrated the good possibility of replacing themanual dosing of solid calcium hydroxide as a pH-regulating chemical with anautomatic dosing of sodium hydroxide obtained in liquid form.

High yield production of benzaldehyde in the solvent-free oxidation of benzyl alcohol by using green catalysts is highly desirable. In this work, calcium hydroxide derived from waste clamshell was used as low-cost and environmentally friendly catalyst support (CaSUP) for Pd and V nanoparticles. The physicochemical properties of the catalysts were analyzed using X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) technique, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The catalytic oxidation of benzyl alcohol to benzaldehyde was studied in a liquid phase reaction by using H2O2 as an oxidizing agent. The effects of catalyst loading, the molar ratio of hydrogen peroxide to benzyl alcohol, temperature and reaction duration were investigated. In the optimized conditions, Pd nanoparticles supported on clamshell-derived supports displayed excellent catalytic conversion (88%) and selectivity to benzaldehyde (89%). Furthermore, the catalyst can be effectively reused without a significant loss in its activity and selectivity. The high yield and stability can be related to the structural and basic properties of the catalyst. These results provide important insights into the benzyl alcohol oxidation process for industrial applications.

Objective: To observe the incidence of post-operative pain after single-visit Non-Surgical Endodontic Therapy (NSET) in teeth with symptomatic apical periodontitis disinfected with Photo-Activated Disinfection (PAD). Methods: Single-rooted teeth (N=30) with pulp necrosis and symptomatic apical periodontitis were included. Subsequent to chemo mechanical preparation, the teeth were randomly distributed into two groups: group I (n=15) which received calcium hydroxide slurry as an intracanal medicament and group II (n=15) which received PAD and obturation in the same visit. Postoperative pain was recorded at 4, 24, 48 and72 hours using a visual analog pain scale. One-way analysis of variance post hoc Tukey test was used to compare the score. Results: There was a significant reduction in pain after instrumentation in Groups I and II. The pain reduction was more in group I as compared to group II at 4 hours. There was no statistically significant difference seen in both the groups at 24, 48 and 72 hours postoperatively. Conclusion: Application of PAD as an adjunct in single visit NSET has no noticeable difference in pain perception when compared with the use of calcium hydroxide interim dressing in two visits NSET.

Objective: To observe the incidence of post-operative pain after single-visit Non-Surgical Endodontic Therapy (NSET) in teeth with symptomatic apical periodontitis disinfected with Photo-Activated Disinfection (PAD). Methods: Single-rooted teeth (N=30) with pulp necrosis and symptomatic apical periodontitis were included. Subsequent to chemo mechanical preparation, the teeth were randomly distributed into two groups: group I (n=15) which received calcium hydroxide slurry as an intracanal medicament and group II (n=15) which received PAD and obturation in the same visit. Postoperative pain was recorded at 4, 24, 48 and72 hours using a visual analog pain scale. One-way analysis of variance post hoc Tukey test was used to compare the score. Results: There was a significant reduction in pain after instrumentation in Groups I and II. The pain reduction was more in group I as compared to group II at 4 hours. There was no statistically significant difference seen in both the groups at 24, 48 and 72 hours postoperatively. Conclusion: Application of PAD as an adjunct in single visit NSET has no noticeable difference in pain perception when compared with the use of calcium hydroxide interim dressing in two visits NSET.

This study offers a new tool to restorers to bleach paper documents: artificial light radiation (ALR). It is a controlled method that is an alternative to other highly aggressive procedures that have been ap plied to cellulose based media. Its main novelty is its intrinsic lighting characteristics which guarantee uniformity and avoid heating the paper. The results of testing this new tool were compared to those of bleaching with hydrogen peroxide (H2O2). Each of the two methods was applied to five different types of widely used paper: Arches and Somerset (brands serving for engraving and digital printing), Ingres (drawing), press-type (magazines and newspapers) and Bible-type (historical documents). Once charac terised by physico-mechanical, chemical and optical parameters (grammage, thickness, specular gloss, optical properties, air permeance, tensile properties, determining the pH of both surface and aqueous extracts), the different papers were bleached by the two methods according to pre-established criteria. Finally, to determine the evolution and effects of the two treatments, the papers were subjected to accel erated agein

In this study, we targeted a calcium hydroxide and ettringite composite-type expansive additive (EA) and obtained the basic characteristics of the EA mixed cement paste in order to create a method for calculating volume expansion based on the hydration reaction of the PCEA system. Expansion strain, setting time, and compressive strength were measured. In addition, we observed the state of EA after hydration using a micro-CT scanner and scanning electron microscope, and elucidated the expansion mechanism. Our results show that strain rapidly increased and the compressive strength decreased when the replacement ratio of the EA (Crep) exceeds 6.4%. At the same time, radial cracks were generated from the hydrated EA particles, suggesting that the EA itself grew to expand the cement paste. Although no ettringite was confirmed inside the EA when the Crep was 5.1%, when the Crep was 10.3%, ettringite was formed vertically from the surface of C3A with a large amount of pores. These results show that simultaneous formation of ettringite and pores causes rapid expansion.

The article discusses the processes of high-temperature gypsum binder from the Khujakul deposit of the Republic of Karakalpakstan, in the temperature range of 550-1000°C and simulating the decomposition of its compositions, the phase composition of the resulting products, the main patterns of structure formation are established depending on the phase composition of the original binder.The results of the influence of the concentration of Ca(OH)2 on the strength of the structure in concentrated suspensions of gypsum at different temperatures are presented.The ways of regulating the properties of various gypsum binders with the help of additives and rational use of natural gypsum for the production of high-temperature gypsum binder for rocks with a predominance of the clay-carbonate part have been determined.21 As a result of high-temperature firing (800-1000°C) of carbonate-gypsum mixtures,a binder material with the ability to hydraulic hardening can be obtained.

In this study, we targeted a calcium hydroxide and ettringite composite-type expansive additive (EA) and obtained the basic characteristics of the EA mixed cement paste in order to create a method for calculating volume expansion based on the hydration reaction of the PCEA system. Expansion strain, setting time, and compressive strength were measured. In addition, we observed the state of EA after hydration using a micro-CT scanner and scanning electron microscope, and elucidated the expansion mechanism. Our results show that strain rapidly increased and the compressive strength decreased when the replacement ratio of the EA (Crep) exceeds 6.4%. At the same time, radial cracks were generated from the hydrated EA particles, suggesting that the EA itself grew to expand the cement paste. Although no ettringite was confirmed inside the EA when the Crep was 5.1%, when the Crep was 10.3%, ettringite was formed vertically from the surface of C3A with a large amount of pores. These results show that simultaneous formation of ettringite and pores causes rapid expansion., Materials and Environment

Ozonated sunflower oil is an alternative to intracanal medication in root canal treatment. Thus, the aim of this study is to evaluate whether ozonated sunflower oil is effectively removed from the root canal with Passive Ultrasonic Irrigation and the XP-Endo Finisher. Materials and methods: Twenty-three human single-root teeth were selected for this experiment. Teeth were divided into 2 groups according intracanal medication, G1: Ultracal calcium hydroxide, and G2: ozonated sunflower oil, and then subdivided according to complementary techniques: G1A (n=5): sunflower ozonated oil + PUI; G1B (n=5): ozonated sunflower oil + XP-Endo Finisher; G2A (n=5): Ultracal calcium hydroxide + PUI; G2B (n=5): Ultracal calcium hydroxide + XP-Endo Finisher; G3 Control (n=3): no intracanal medication. After chemomechanical preparation up to R25 or R40 Reciproc files, root canals were filled with intracanal medication according to experimental groups and remained in a wet chamber for 14 days. The teeth were then treated according to subgroups. Samples were prepared for SEM evaluation and images were analyzed by one evaluator. Data were tabulated and underwent Kruskal-Wallis and Mann-Whitey testing (p< 0.05). Results: Image analyses showed all tested protocols were effective in the removal of intracanal medication, but there was no statistical significance among them. Conclusion: Passive ultrasonic irrigation and the XP-Endo Finisher were effective in the removal of ozonated sunflower oil from root canals.

The roles of sodium hydroxide, calcium hydroxide and temperature on heat flow evolution and its relation to the reaction stages of alkali-activated coal fly ash were evaluated. The response surface method was used to analyse data. Both the heat flow and kinetic parameters were determined by the deconvolution of microcalorimetric signals at 25, 35 and 45°C. The studied factors were found to have a strong influence on the dissolution of ash rich in aluminium units, on the diffusion-nucleation processes and its growth, both initial and final. A sodium hydroxide concentration of 8 M guaranteed optimal reorganisation of the dissolved units to form the reaction products. Calcium hydroxide altered the aluminium distribution in the paste, acting as nucleation spots and intervening in the formation of initial and final reaction products. High temperatures were found to favour the efficiency of the alkali activation, increasing the rate constant and simplifying the expiration of energy barriers. Knowledge of the heat flow evolution in these kinds of cementitious materials will allow manipulation of the characteristics of the mixtures in both the fresh and hardened state.

The article discusses the processes of high-temperature gypsum binder from the Khujakul deposit of the Republic of Karakalpakstan, in the temperature range of 550-1000°C and simulating the decomposition of its compositions, the phase composition of the resulting products, the main patterns of structure formation are established depending on the phase composition of the original binder.The results of the influence of the concentration of Ca(OH)2 on the strength of the structure in concentrated suspensions of gypsum at different temperatures are presented.The ways of regulating the properties of various gypsum binders with the help of additives and rational use of natural gypsum for the production of high-temperature gypsum binder for rocks with a predominance of the clay-carbonate part have been determined.21 As a result of high-temperature firing (800-1000°C) of carbonate-gypsum mixtures,a binder material with the ability to hydraulic hardening can be obtained.

The article discusses the processes of high-temperature gypsum binder from the Khujakul deposit of the Republic of Karakalpakstan, in the temperature range of 550-1000°C and simulating the decomposition of its compositions, the phase composition of the resulting products, the main patterns of structure formation are established depending on the phase composition of the original binder.The results of the influence of the concentration of Ca(OH)2 on the strength of the structure in concentrated suspensions of gypsum at different temperatures are presented.The ways of regulating the properties of various gypsum binders with the help of additives and rational use of natural gypsum for the production of high-temperature gypsum binder for rocks with a predominance of the clay-carbonate part have been determined.21 As a result of high-temperature firing (800-1000°C) of carbonate-gypsum mixtures,a binder material with the ability to hydraulic hardening can be obtained.

The article discusses the processes of high-temperature gypsum binder from the Khujakul deposit of the Republic of Karakalpakstan, in the temperature range of 550-1000°C and simulating the decomposition of its compositions, the phase composition of the resulting products, the main patterns of structure formation are established depending on the phase composition of the original binder.The results of the influence of the concentration of Ca(OH)2 on the strength of the structure in concentrated suspensions of gypsum at different temperatures are presented.The ways of regulating the properties of various gypsum binders with the help of additives and rational use of natural gypsum for the production of high-temperature gypsum binder for rocks with a predominance of the clay-carbonate part have been determined.21 As a result of high-temperature firing (800-1000°C) of carbonate-gypsum mixtures,a binder material with the ability to hydraulic hardening can be obtained.

The article discusses the processes of high-temperature gypsum binder from the Khujakul deposit of the Republic of Karakalpakstan, in the temperature range of 550-1000°C and simulating the decomposition of its compositions, the phase composition of the resulting products, the main patterns of structure formation are established depending on the phase composition of the original binder.The results of the influence of the concentration of Ca(OH)2 on the strength of the structure in concentrated suspensions of gypsum at different temperatures are presented.The ways of regulating the properties of various gypsum binders with the help of additives and rational use of natural gypsum for the production of high-temperature gypsum binder for rocks with a predominance of the clay-carbonate part have been determined.21 As a result of high-temperature firing (800-1000°C) of carbonate-gypsum mixtures,a binder material with the ability to hydraulic hardening can be obtained.

The article discusses the processes of high-temperature gypsum binder from the Khujakul deposit of the Republic of Karakalpakstan, in the temperature range of 550-1000°C and simulating the decomposition of its compositions, the phase composition of the resulting products, the main patterns of structure formation are established depending on the phase composition of the original binder.The results of the influence of the concentration of Ca(OH)2 on the strength of the structure in concentrated suspensions of gypsum at different temperatures are presented.The ways of regulating the properties of various gypsum binders with the help of additives and rational use of natural gypsum for the production of high-temperature gypsum binder for rocks with a predominance of the clay-carbonate part have been determined.21 As a result of high-temperature firing (800-1000°C) of carbonate-gypsum mixtures,a binder material with the ability to hydraulic hardening can be obtained.

A laboratory study is presented of the rotary-kiln pre-reduction and oxygen bath-smelting process for pellets comprising vanadium-titanium magnetite concentrate (from Panzhihua region, Sichuan province, China), coal and calcium hydroxide flux. The chemical and mineralogical compositions of the iron particles and slag are investigated using X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analyses. The influence of the slag basicity, smelting temperature, smelting time and pulverised coal addition on the slag-iron separation is determined. The results indicate that the optimum smelting parameters are smelting temperature above 1 450 degrees C, slag basicity above 0.8, smelting time 30-40 min and coal addition 20-22%. The sulphur content of the iron particles achieves 0.23 and 0.21% at 1 450 and 1 500 degrees C, respectively, at a slag basicity of 1.1, and the titanium dioxide content reaches above 38%., A laboratory study is presented of the rotary-kiln pre-reduction and oxygen bath-smelting process for pellets comprising vanadium-titanium magnetite concentrate (from Panzhihua region, Sichuan province, China), coal and calcium hydroxide flux. The chemical and mineralogical compositions of the iron particles and slag are investigated using X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analyses. The influence of the slag basicity, smelting temperature, smelting time and pulverised coal addition on the slag-iron separation is determined. The results indicate that the optimum smelting parameters are smelting temperature above 1 450 degrees C, slag basicity above 0.8, smelting time 30-40 min and coal addition 20-22%. The sulphur content of the iron particles achieves 0.23 and 0.21% at 1 450 and 1 500 degrees C, respectively, at a slag basicity of 1.1, and the titanium dioxide content reaches above 38%.

In this study, we targeted a calcium hydroxide and ettringite composite-type expansive additive (EA) and obtained the basic characteristics of the EA mixed cement paste in order to create a method for calculating volume expansion based on the hydration reaction of the PCEA system. Expansion strain, setting time, and compressive strength were measured. In addition, we observed the state of EA after hydration using a micro-CT scanner and scanning electron microscope, and elucidated the expansion mechanism. Our results show that strain rapidly increased and the compressive strength decreased when the replacement ratio of the EA (Crep) exceeds 6.4%. At the same time, radial cracks were generated from the hydrated EA particles, suggesting that the EA itself grew to expand the cement paste. Although no ettringite was confirmed inside the EA when the Crep was 5.1%, when the Crep was 10.3%, ettringite was formed vertically from the surface of C3A with a large amount of pores. These results show that simultaneous formation of ettringite and pores causes rapid expansion., Materials and Environment

In this study, we targeted a calcium hydroxide and ettringite composite-type expansive additive (EA) and obtained the basic characteristics of the EA mixed cement paste in order to create a method for calculating volume expansion based on the hydration reaction of the PCEA system. Expansion strain, setting time, and compressive strength were measured. In addition, we observed the state of EA after hydration using a micro-CT scanner and scanning electron microscope, and elucidated the expansion mechanism. Our results show that strain rapidly increased and the compressive strength decreased when the replacement ratio of the EA (Crep) exceeds 6.4%. At the same time, radial cracks were generated from the hydrated EA particles, suggesting that the EA itself grew to expand the cement paste. Although no ettringite was confirmed inside the EA when the Crep was 5.1%, when the Crep was 10.3%, ettringite was formed vertically from the surface of C3A with a large amount of pores. These results show that simultaneous formation of ettringite and pores causes rapid expansion.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Calcium hydroxide nanoparticles (nanolime) are a novel solution for consolidating clay-based plasters and adobes in cultural heritage constructions. The suspension is applied as a coating and fully compatible with calcareous earthen materials. Ca(OH)2 nanoparticles (NPs) are transformed into protective CaCO3 coatings due to a carbonation reaction. This work aims to study the effectiveness of Ca(OH)2 NPs coatings in protecting the surface of earthen plasters. To do this, the effect of nanolime on surface consolidation, water permeability and durability in front of rain action is evaluated. It was found that the treatment improved the superficial cohesion and reduced water permeability of plasters due to formation of calcareous coatings and partial obstruction of pores on the surface. In contrast, the effectiveness of the treatment is not demonstrated against rainwater and acid environments (HCl). Finally, acid rain simulation (H2SO4) led to deposition of protective films of gypsum that might delay the plaster deterioration in the long term.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Currently, in the steel industry, a manufacturing methodology is not approved to produce 1-inch specimens, obtained from a 1045 steel bar, which are subjected to a heat treatment with the novel cooling method based on concentrations of hydroxide of carbon. calcium (dietary lime) to conduct a study. Through this study, the relationship between traditional tempering methods (oil, water and brine) was compared with the experimental form of tempering based on calcium hydroxide; Through the process of observing the behavior of hardness in its alpha and gamma state to demonstrate that this experimental method is feasible for its implementation in heat treatments within the industry. Statistical data were evaluated to compare hardness and determine if they were different from traditional cooling methods and the existence of a structural change was measured. After the application of the new method, different structural changes were obtained depending on the change of calcium hydroxide concentrate, temperature and cooling time., Actualmente, en la industria del acero, no está aprobada una metodología de fabricación para elaborar probetas de 1plg, obtenidas de una barra de acero 1045, las que se sometan a un tratamiento térmico con el novedoso método de enfriamiento a base de concentraciones de hidróxido de calcio (cal alimenticia) para llevar a cabo un estudio. Mediante este estudio se comparó la relación que tienen los métodos tradicionales de temple (aceite, agua y salmuera) con la forma experimental de temple a base de hidróxido de calcio; a través del proceso de observación del comportamiento de la dureza en su estado alfa y gama para demostrar que este método experimental es factible para su implementación en los tratamientos térmicos dentro de la industria. Se evaluaron datos estadísticos para comparar dureza y determinar si fueron diferentes a los métodos de enfriamiento tradicional y se midió la existencia de un cambio estructural. Posterior a la aplicación del nuevo método se obtuvieron distintos cambios estructurales dependiendo del cambio de concentrado de hidróxido de calcio, temperatura y tiempo de enfriamiento.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Currently, in the steel industry, a manufacturing methodology is not approved to produce 1-inch specimens, obtained from a 1045 steel bar, which are subjected to a heat treatment with the novel cooling method based on concentrations of hydroxide of carbon. calcium (dietary lime) to conduct a study. Through this study, the relationship between traditional tempering methods (oil, water and brine) was compared with the experimental form of tempering based on calcium hydroxide; Through the process of observing the behavior of hardness in its alpha and gamma state to demonstrate that this experimental method is feasible for its implementation in heat treatments within the industry. Statistical data were evaluated to compare hardness and determine if they were different from traditional cooling methods and the existence of a structural change was measured. After the application of the new method, different structural changes were obtained depending on the change of calcium hydroxide concentrate, temperature and cooling time., Actualmente, en la industria del acero, no está aprobada una metodología de fabricación para elaborar probetas de 1plg, obtenidas de una barra de acero 1045, las que se sometan a un tratamiento térmico con el novedoso método de enfriamiento a base de concentraciones de hidróxido de calcio (cal alimenticia) para llevar a cabo un estudio. Mediante este estudio se comparó la relación que tienen los métodos tradicionales de temple (aceite, agua y salmuera) con la forma experimental de temple a base de hidróxido de calcio; a través del proceso de observación del comportamiento de la dureza en su estado alfa y gama para demostrar que este método experimental es factible para su implementación en los tratamientos térmicos dentro de la industria. Se evaluaron datos estadísticos para comparar dureza y determinar si fueron diferentes a los métodos de enfriamiento tradicional y se midió la existencia de un cambio estructural. Posterior a la aplicación del nuevo método se obtuvieron distintos cambios estructurales dependiendo del cambio de concentrado de hidróxido de calcio, temperatura y tiempo de enfriamiento.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Currently, in the steel industry, a manufacturing methodology is not approved to produce 1-inch specimens, obtained from a 1045 steel bar, which are subjected to a heat treatment with the novel cooling method based on concentrations of hydroxide of carbon. calcium (dietary lime) to conduct a study. Through this study, the relationship between traditional tempering methods (oil, water and brine) was compared with the experimental form of tempering based on calcium hydroxide; Through the process of observing the behavior of hardness in its alpha and gamma state to demonstrate that this experimental method is feasible for its implementation in heat treatments within the industry. Statistical data were evaluated to compare hardness and determine if they were different from traditional cooling methods and the existence of a structural change was measured. After the application of the new method, different structural changes were obtained depending on the change of calcium hydroxide concentrate, temperature and cooling time., Actualmente, en la industria del acero, no está aprobada una metodología de fabricación para elaborar probetas de 1plg, obtenidas de una barra de acero 1045, las que se sometan a un tratamiento térmico con el novedoso método de enfriamiento a base de concentraciones de hidróxido de calcio (cal alimenticia) para llevar a cabo un estudio. Mediante este estudio se comparó la relación que tienen los métodos tradicionales de temple (aceite, agua y salmuera) con la forma experimental de temple a base de hidróxido de calcio; a través del proceso de observación del comportamiento de la dureza en su estado alfa y gama para demostrar que este método experimental es factible para su implementación en los tratamientos térmicos dentro de la industria. Se evaluaron datos estadísticos para comparar dureza y determinar si fueron diferentes a los métodos de enfriamiento tradicional y se midió la existencia de un cambio estructural. Posterior a la aplicación del nuevo método se obtuvieron distintos cambios estructurales dependiendo del cambio de concentrado de hidróxido de calcio, temperatura y tiempo de enfriamiento.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

The elimination of calcium hydroxide in the root canal is decisive for the success of endodontic treatment, the remnants can interact negatively with endodontic sealants increasing filtrations and decreasing the quality of the seal. Objective: To evaluate the effect of intra-duct medication with calcium hydroxide paste on the penetration of the sealing cement inside the dentinal tubules. Materials and methods: 20 distal roots of upper molars were instrumented using the Wave One Large 40 / .08 System. They were randomly divided into two groups: one sealed with a single cone technique and Ah plus cement with rhodamine-B and another sealed with the same technique and Ah plus cement with rhodamine B, previous placement for 15 days and removal by recapping the paste calcium hydroxide. Subsequently, the teeth were cut transversely and photomicrographs of the cervical, middle and apical third were performed using the laser scanning confocal microscopy technique. The maximum depth of penetration was determined through the Image J program. Results: The Ah plus sealing cement had lower penetration values when the calcium hydroxide paste was previously used as an intra-channel medication (p <0.01). The third of the duct with the highest penetration was the cervical third followed by the middle third and finally the apical (p <0.01). Conclusion: Remaining calcium hydroxide decreases the penetration of the sealing cement Ah plus in the dentinal tubules in all thirds of the root canal., Los agentes utilizados en blanqueamiento dental provocan una respuesta inflamatoria de la pulpa, que depende de la concentración y el tiempo de aplicación de la sustancia empleada. Objetivo: Evaluar el nivel de penetración del blanqueamiento a base de peróxido de carbamida a diferentes concentraciones: 10, 20 y 35% dentro de la cámara pulpar. Materiales y métodos: Se utilizaron 120 terceros molares humanos extraídos, divididos aleatoriamente en cuatro grupos (n=30): grupo A: control; grupo B: 10% gel de Peróxido de Carbamida (CP del inglés Carbamide Peroxide); grupo C: 20% gel CP y grupo D: 35% gel CP. Los dientes se cortaron 2 mm por debajo del límite amelocementario con una máquina de corte, se colocó buffer de acetato en la cámara pulpar y se aplicó por 40 minutos el agente clareador una sola vez. Los dientes se mantuvieron a temperatura ambiente (25°C) durante el proceso. La penetración de CP se estimó con cristal violeta y peroxidasa de rábano picante, en un espectrofotómetro de absorbancia. Los datos fueron analizados mediante las pruebas estadísticas ANOVA complementada con el Test post Hoc de Tukey con un grado de significancia al 5%. Resultados: Las medias obtenidas para el Grupo B fueron de 0,062 mg (±0,018), para el Grupo C fueron de 0,063 mg (±0,017), y para el Grupo D fueron de 0,086 mg (±0,024). Existiendo diferencia significativa (p= <0.05) del grupo D con relación a los otros grupos. Conclusión: la penetración de CP en la cavidad pulpar depende de la concentración, siendo mayor en concentración al 35%.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.

Several factors often intervene in the cessation of root development, the main culprits being caries and trauma, which result in pulp necrosis, for the clinical approach of this condition the process of apicoformation with Ca(OH)2, therefore a retrospective review of this treatment has been carried out, relying on the use of search tools such as Scielo Digital Library, PUBMED, University Repositories, Dynamed, and Proquest; based on scientific articles, clinical case reports and specialty books studied, it was determined that Ca(OH)2, thanks to its properties, is the material of choice to favor apical closure in necrotic teeth with immature apex., Varios factores intervienen a menudo en el cese de desarrollo radicular, siendo los principales responsables la caries y los traumatismos, que tienen como consecuencia la necrosis pulpar, para el abordaje clínico de dicha condición se debe llevar a cabo el proceso de apicoformación con Ca(OH)2, por lo tanto se ha realizado una revisión retrospectiva de este tratamiento, apoyándonos en el uso de herramientas de búsqueda como: Biblioteca Digital Scielo, PUBMED , Repositorios universitarios, Dynamed y Proquest; basándonos en los artículos científicos, reportes de casos clínicos y libros de espe- cialidad estudiados, se determinó que el Ca(OH)2 gracias a sus propiedades, es el material de elección para favorecer el cierre apical en dientes necróticos con ápice inmaduro.