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Data in this article are associated with our research article "Dental Resin Monomers Induce Early and Potent Oxidative Damage on Human Odontoblast-like Cells." Dental adhesives are polymeric compounds consisting of several chemical substances, including resin monomers, such as 2-hydroxyethyl methacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA), together with other comonomers, making up the organic matrix of the adhesive and whose composition is based on the methyl methacrylate chemistry. The release of residual monomers, susceptible to biodegradation, acts as a source of bioactive compounds, which can interact with tissues and induce a cytotoxic cellular response. The most used techniques to evaluate cytotoxicity, proliferation, or metabolic activity of cells exposed to different substances, are MTT and resazurin. Each chemistry evaluates cell viability differently, so the data obtained could vary depending on the technique sensitivity to detect changes in cell metabolism. The objective of this article was to present viability data as a function of the metabolic activity in human odontoblast-like cells (hOLCs), exposed to 3, 6, 9, and 12 mM HEMA, or 0.75, 1.5, 3, and 6 mM TEGDMA evaluated by the MTT, and resazurin techniques in the first 24 hours of exposure, at different time points. The absorbance data for the MTT test and the fluorescence intensity for the resazurin test were obtained by spectrometry. SIMSTAT software 2.6.5 for Windows was used to confirm the normal data distribution (Levene's test). Subsequently, an analysis of variance (one-way ANOVA) was performed to compare the control with each HEMA and TEGDMA concentration. Where a p < 0.05 indicated a high F value, a Fisher's least significant differences post-hoc analysis was performed, using an alpha value < 0.05. Data from the different time points were compared with a Student's t-test for each concentration. These data may be useful to compare the cytotoxic response of hOLCs with other cell types or the cell response to other resin monomers.

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In this work, we report the synthesis of a mesoporous molecularly imprinted polymer on the surface of silica nanoparticles (core@mMIP) to be applied as adsorbent in microextraction by packed sorbent (MEPS) for selective determination of pesticides in apple juice. The core@mMIP was properly characterized, showing good adhesion of the polymer to the silica core. The best extraction conditions were: 200 µL of ultrapure water as washing solvent, 150 µL of acetonitrile as eluent, 100 µL of sample at pH 2.5, five draw-eject cycles and 8 mg of adsorbent. Thereby, recoveries of 96.12 ± 1.05%, 76.88 ± 6.18% and 76.18 ± 5.57% were obtained for pyriproxyfen (PPX), deltamethrin (DTM) and etofenprox (ETF), respectively. After validation, the method presented linearity in the range of 0.02-10 µg mL-1 (r > 0.99), limit of detection of 0.005 µg mL-1, satisfactory selectivity, and proper precision and accuracy. The method was successfully applied real samples of processed and fresh apple juice.

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Resumo O estudo objetivou conhecer a percepção dos enfermeiros sobre a utilização do hidrogel em lesões por pressão. Trata-se de pesquisa com abordagem qualitativa realizada em uma instituição hospitalar pública de João Pessoa/Paraíba, onde a amostra foi composta por 17 enfermeiros atuantes no Centro de Terapia Intensiva, comissão de pele e sala vermelha. Os dados foram coletados através de uma entrevista utilizando um formulário semiestruturado, e a análise deu-se por meio da técnica de Análise de Conteúdo Temática. Foi revelado que existem fragilidades no que concerne aos conhecimentos dos enfermeiros em relação às lesões por pressão e à aplicação hidrogel. Observando-se a necessidade de realizar educação continuada nos serviços de saúde, com o objetivo de atenuar as limitações de conhecimentos dos enfermeiros no que se refere ao conceito, à classificação e às causas das lesões por pressão, bem como sobre a utilização do hidrogel.

Abstract The study aimed to know the perception of nurses about the use of hydrogels in pressure injuries. This is a research with a qualitative approach conducted in a public hospital in João Pessoa / Paraíba, where the sample consisted of 17 nurses working in the Intensive Care Center, skin committee and red room. Data were collected through an interview using a semi-structured form, and the analysis was performed using the Thematic Content Analysis. It was revealed that there are weaknesses regarding nurses' knowledge regarding pressure injuries and hydrogel application. Noting the need for continuing education in health services, with the aim of alleviating nurses' knowledge limitations regarding the concept, classification and causes of pressure injuries, as well as the use of hydrogel.

Resumen El estudio tuvo como objetivo conocer la percepción de las enfermeras sobre el uso de hidrogeles en lesiones por presión. Esta es una investigación con un enfoque cualitativo realizada en un hospital público en João Pessoa / Paraíba, donde la muestra consistió en 17 enfermeras que trabajan en el Centro de Cuidados Intensivos, el comité de la piel y la sala roja. Los datos fueron recolectados a través de una entrevista usando una forma semiestructurada, y el análisis se realizó usando la técnica de Análisis de Contenido Temático. Se reveló que existen debilidades con respecto al conocimiento de las enfermeras con respecto a las lesiones por presión y la aplicación de hidrogel. Observando la necesidad de educación continua en los servicios de salud, con el objetivo de aliviar las limitaciones de conocimiento de las enfermeras con respecto al concepto, clasificación y causas de las lesiones por presión, así como el uso de hidrogel.

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Introdução: O aparelho ortodôntico passivo esporão é um método utilizado em crianças para correção de mordida aberta anterior. Para realizar a fixação desses acessórios dentes é necessário a utilização de materiais resinosos que podem liberar subprodutos tóxicos como BisGMA e TEGDMA. Além disso, a movimentação dentária ortodôntica pode aumentar a concentração de interleucinas no fluido crevicular gengival (FCG). A liberação de subprodutos resinosos no tratamento de mordida aberta e o comportamento da expressão de interleucinas ainda não estão elucidados na literatura. Objetivo: (1) avaliar a expressão de citocinas no FCG em crianças com mordida aberta que receberam fixação de esporão como tratamento e (2) quantificar o BisGMA e TEGDMA na saliva desses pacientes; e (3) avaliar a migração e viabilidade de quetarinócitos humanos expostos à resina. Métodos: Foram selecionados pacientes da clínica da FO-UFMG que apresentaram mordida aberta anterior. A colagem dos esporões foi realizada e os excessos de resina foram removidos. Foram realizados exames clínico e periodontal nos incisivos superiores e inferiores, coletas do FCG (antes da colagem ­ baseline, 24 h e 7 d após) e saliva (baseline, 30 min, 24 h e 7 d após a colagem). As citocinas do FCG foram analisadas por meio do BD™ Cytometric Bead Array e as amostras de saliva, através do método de cromatografia líquida de alta eficiência. Para as análises in vitro, células imortalizadas HaCat foram tratadas com meio de cultura condicionados com incrementos do sistema resinoso em 3 diferentes diluições e posteriormente foram realizados os testes de viabilidade e migração celular. Resultados: O estudo in vivo demonstrou que houve aumento do sangramento gengival nos incisivos inferiores após 7d quando comparados ao baseline e que este índice estava maior nos dentes inferiores do que nos superiores. Em 24h e 7d após a fixação do esporão, os níveis de IL-8 nos incisivos superiores estavam aumentados. Em 7d, a concentração de IL-1ß foi aumentada em comparação ao baseline nos dois grupos de dentes. Comparando os incisivos superiores e inferiores, os níveis de IL-8, IL-1ß e IL-6 foram maiores nos superiores às 24h. A produção de citocinas pôde ser positivamente correlacionada com o aumento do volume do FCG. Houve aumento dos níveis de BisGMA e TEGDMA na saliva em 30min, com redução dos níveis em 24h e 7d. Os resultados in vitro demonstraram aumento da migração celular nos queratinóscitos expostos aos meios condicionados mesmo em baixas concentrações .Conclusão: Foi identificado que após a colagem do esporão lingual ocorreu o aumento na expressão de interleucinas no FCG. Além disso, foi possível identificar a liberação de subprodutos resinosos na saliva das crianças. Embora os mesmos possam interferir na migração celular, não há estudos que quantifiquem a exposição mínima capaz de induzir alterações no indivíduo. Sendo assim, os benefícios da colagem do esporão sobrepõem seus efeitos adversos

Introduction: The passive spur orthodontic appliance is a method used in children to correct anterior open bite. To fix these teeth accessories, it is necessary to use resinous materials that can release toxic by-products such as BisGMA and TEGDMA. In addition, orthodontic tooth movement can increase the concentration of interleukins in the gingival crevicular fluid (FCG). The release of resinous by-products in the treatment of open bite and the behavior of interleukin expression are not yet elucidated in the literature. Objective: (1) to evaluate the expression of cytokines in the FCG in children with open bite who received spur fixation as treatment and (2) to quantify the BisGMA and TEGDMA in the saliva of these patients; and (3) evaluate the migration and viability of human ketarinocytes exposed to the resin. Methods: Patients from the FO-UFMG clinic who presented anterior open bite were selected. The spurs were bonded and the excess resin was removed. Clinical and periodontal examinations were performed on the upper and lower incisors, collections of the FCG (before bonding - baseline, 24 h and 7 d after) and saliva (baseline, 30 min, 24 h and 7 d after bonding). The FCG cytokines were analyzed using the BD ™ Cytometric Bead Array and the saliva samples, using the high performance liquid chromatography method. For in vitro analysis, immortalized HaCat cells were treated with culture medium conditioned with increments of the resin system in 3 different dilutions and then the viability and cell migration tests were performed. Results: The in vivo study showed that there was an increase in gingival bleeding in the lower incisors after 7d when compared to the baseline and that this index was higher in the lower than in the upper teeth. At 24h and 7d after spur fixation, IL-8 levels in the upper incisors were increased. At 7d, the concentration of IL-1ß was increased compared to the baseline in the two groups of teeth. Comparing the upper and lower incisors, the levels of IL-8, IL-1ß and IL-6 were higher in those above 24h. Cytokine production could be positively correlated with increased FCG volume. There was an increase in the levels of BisGMA and TEGDMA in saliva in 30 minutes, with a reduction in levels in 24h and 7d. The in vitro results demonstrated an increase in cell migration in keratinocytes exposed to conditioned media even in low concentrations. Conclusion: It was identified that after the gluing of the tongue spur there was an increase in the expression of interleukins in the FCG. In addition, it was possible to identify the release of resinous by-products in children's saliva. Although they can interfere with cell migration, there are no studies that quantify the minimum exposure capable of inducing changes in the individual. Therefore, the benefits of spur bonding override its adverse effects.

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ABSTRACT: The objective of this study was to compare the polymerization shrinkage of Eclipse photopolymerization resin for prosthesis based on urethane dimethacrylate (UDMA) with that of three heat-cured acrylic resins based on polymethyl methacrylate (PMMA) after the polymerization process and immersion in water. A total of 40 prostheses were fabricated on a standard metallic upper edentulous model: group 1, Eclipse; group 2, Triplex hot; group 3, Veracril; and group 4, Lucitone 199. Subsequently, the polymerization contraction was tested using a microscope in which measurements were made in micrometres at 3 points located in the middle parts of the right and left sides and the middle part of the palate at three time points once the prosthesis was completed, after 30 days of immersion in water for 8 hours a day at a temperature of 37 °C, and after cutting the prosthesis at the level of the second premolar. ANOVA revealed that the contraction of the polymerization no statistically significant differences between the groups, (P> 0.05). The type of resin and its interaction with the processing method behaves similarly for all test resins. The Veracril heat-cured resin obtained the lowest contraction value in the three measurements (mm) and the highest value was obtained with the Eclipse photopolymerization resin. The Eclipse resin exhibited no lower polymerization shrinkage compared to conventional acrylic resins based on polymethyl methacrylate (PMMA), however it was not significantly affected by immersion in water.

RESUMEN: El objetivo de este estudio fue comparar la contracción de polimerización de la resina de fotopolimerización Eclipse para prótesis basadas en dimetacrilato de uretano (UDMA) con la de tres resinas acrílicas curadas con calor a base de polimetacrilato de metilo (PMMA) después del proceso de polimerización e inmersión en agua. Se fabricaron un total de 40 prótesis en un modelo edéntulo superior metálico estándar: grupo 1, Eclipse; grupo 2, triplex caliente; grupo 3, veracril; y grupo 4, Lucitone 199. Posteriormente, la contracción de la polimerización se probó utilizando un microscopio en el que se realizaron mediciones en micrometros en 3 puntos ubicados en las partes medias de los lados derecho e izquierdo y la parte media del paladar en tres puntos de tiempo una vez la prótesis se completó, después de 30 días de inmersión en agua durante 8 horas al día a una temperatura de 37 °C, y después de cortar la prótesis a nivel del segundo premolar. ANOVA reveló que la contracción de la polimerización no presenta diferencias estadísticamente significativas entre los grupos, (P> 0,05). El tipo de resina y su interacción con el método de procesamiento se comportan de manera similar para todas las resinas de prueba. La resina curada con calor Veracril obtuvo el valor de contracción más bajo en las tres mediciones (mm) y el valor más alto se obtuvo con la resina de fotopolimerización Eclipse. La resina Eclipse no mostró una contracción de polimerización menor en comparación con las resinas acrílicas convencionales basadas en polimetilmetacrilato (PMMA), sin embargo, no se vio afectada significativamente por la inmersión en agua.

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This study describes the synthesis of dicalcium phosphate dihydrate (DCPD) particles in the presence of different ethylene glycol dimethacrylates (EGDMA, ethylene glycol/EG units: 1, 2, 3 or 4) at two monomer-to-ammonium phosphate molar ratios (1:1 and 2:1), as a strategy to develop CaP-monomer particles with improved interaction with resin matrices. Particles displaying high surface areas and organic contents were added to a photocurable BisGMA-TEGDMA resin and the resulting materials were tested for degree of conversion (DC), biaxial flexural strength (BFS), flexural modulus, and ion release. Data were subjected to one-way ANOVA or Kruskal-Wallis/Dunn test (alpha: 0.05). Functionalization with EGDMA derivatives was dependent upon the length of the spacer group and monomer concentration in the synthesis. No differences in DC were observed among materials (p > 0.05). A 39% increase in BFS was obtained with the use of particles with the highest functionalization level compared to non-functionalized particles (p < 0.001). The use of functionalized DCPD reduced flexural modulus in comparison to non-functionalized particles (p < 0.001). Calcium release was similar among materials and remained constant during the experiment, while phosphate release was higher at 7 days in comparison to the remaining weeks (p < 0.001). In conclusion, diethylene glycol dimethacrylate resulted in the highest functionalization levels and the highest BFS among DCPD-containing materials. Ion release was not affected by functionalization. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 708-715, 2019.

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In this paper, chitosan was used as protective agent for dual temperature-/pH-sensitive poly(N-vinylcaprolactam-co-itaconic acid-co-ethylene- glycol dimethacrylate)- based hydrogel nanoparticles (poly(NVCL-co-IA-co-EGDMA)) aiming avoid their undesirable colloidal destabilization at different conditions of body human tissues. Thus, poly(NVCL-co-IA-co-EGDMA) was embedded into chitosan and a new solid dispersion was prepared via spray-drying and ketoprofen was used as carrier. Two different sizes of hydrogel nanoparticles (120.6 nm and 185.9 nm) were evaluated and they exhibited a drug encapsulation efficiency of the 39.6% and 57.8%, respectively. The smaller nanoparticles showed to be faster for releasing of ketoprofen at pH 7.4 and 37 °C due to their larger surface area and higher swelling ability. Chitosan played a role of a secondary barrier for the ketoprofen diffusion, extending its release compared to hydrogel nanoparticles alone. Among two concentrations (40 wt% and 70 wt%) of hydrogel nanoparticles related to chitosan, the first one induced higher percentages of ketoprofen release: 74.2% against 64.6%. In addition, the interactions between chitosan matrix and poly(NVCL-co-IA-co-EGDMA) did not change the multi-responsive behavior of hydrogels, suggesting the chitosan was efficient for keeping integrity of nanoparticles hydrogels. Chitosan/poly(NVCL-co-IA-co-EGDMA) hybrid microparticles seems to be a promising new carrier for release of hydrophobic drugs, such as ketoprofen.

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An interim partial removable dental prosthesis (RDP) is any dental prosthesis that replaces some teeth in a partially dentate arch designed to enhance esthetics, stabilization, and/or function for a limited period of time, after which it is to be replaced by a definitive dental prosthesis. This article describes a technique that uses a visible light-polymerized (VLP) resin as the base material for an interim partial RDP. This technique can be easily accomplished in a dental office or laboratory and results in a predictable dental prosthesis. This technique eliminates the need for laboratory processing.

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OBJECTIVES: Enamel resin infiltrants are biomaterials able to treat enamel caries at early stages. Nevertheless, they cannot prevent further demineralization of mineral-depleted enamel. Therefore, the aim of this work was to synthesize and incorporate specific hydroxyapatite nanoparticles (HAps) into the resin infiltrant to overcome this issue. METHODS: HAps were prepared using a hydrothermal method (0h, 2h and 5h). The crystallinity, crystallite size and morphology of the nanoparticles were characterized through XRD, FT-IR and TEM. HAps were then incorporated (10wt%) into a light-curing co-monomer resin blend (control) to create different resin-based enamel infiltrants (HAp-0h, HAp-2h and HAp-5h), whose degree of conversion (DC) was assessed by FT-IR. Enamel caries lesions were first artificially created in extracted human molars and infiltrated using the tested resin infiltrants. Specimens were submitted to pH-cycling to simulate recurrent caries. Knoop microhardness of resin-infiltrated underlying and surrounding enamel was analyzed before and after pH challenge. RESULTS: Whilst HAp-0h resulted amorphous, HAp-2h and HAp-5h presented nanorod morphology and higher crystallinity. Resin infiltration doped with HAp-2h and HAp-5h caused higher enamel resistance against demineralization compared to control HAp-free and HAp-0h infiltration. The inclusion of more crystalline HAp nanorods (HAp-2h and HAp-5h) increased significantly (p<0.05) the DC. SIGNIFICANCE: Incorporation of more crystalline HAp nanorods into enamel resin infiltrants may be a feasible method to improve the overall performance in the prevention of recurrent demineralization (e.g. caries lesion) in resin-infiltrated enamel.

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AIM: To evaluate influence of three different filler particles on an experimental Bisphenol A ethoxylated dimethacrylate (Bis-EMA) based root filling material. MATERIALS AND METHODS: Resin-based endodontic sealers were produced using Bis-EMA, camphorquinone, ethyl 4-dimethylaminobenzoate (EDAB), N, N-dihydroxyethyl-p-toluidine (DHEPT), butylated hydroxytoluene (BHT), and benzoyl peroxide. The experimental groups were formulated adding 10, 20, 30, 40, and 50% of calcium tungstate (CaWO4), ytterbium trifluoride(YbF3), and tantalum oxide(Ta2O5). Flow, thickness, and radiopacity tests were conducted in accordance with ISO 6876. Sorption and solubility (SL) tests were conducted in accordance with ISO 4049, pH was measured with a pH meter, and degree of conversion (DC) was evaluated with Fourier transform infrared spectroscopy (FTIR). For radiopacity, two-way analysis of variance (ANOVA) and Tukey's multiple comparison test was performed. For DC analysis, one-way ANOVA and Tukey's multiple comparison test was performed. All statistical analyses were performed with a significance level of 5%. RESULTS: All groups showed lower flow with increased filler concentration. All groups showed film thickness values lower than 50µm, as ISO recommends, except CaWO450% group (76.7µm). pH values varied from 5.95 (± 0.07) in YbF340% group to 6.90 (± 0.07) in Ta2O540% group. In the radiopacity test, YbF330%, Ta2O540%, and Ta2O550% groups showed no statistical significant difference to 3mmAl. Ta2O5 and YbF3 groups in 10, 20, and 30% concentrations presented sorption and SL values as ISOrecommendation. Addition ofTa2O5 and CaWO4 decreased DC after 14 days. YbF3 addition showed no difference in DC from control group. CONCLUSION: YbF3 filler addition promoted higher properties compared to CaWO4 and Ta2O5 on Bis-EMA based root canal sealer.

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INTRODUCTION: The incorporation of light-curable resins has been proposed for mineral trioxide aggregate (MTA) to improve its properties and reduce its setting time. The aim of the present study was to assess the pH and calcium ion release of an experimental bisphenol A ethoxylate dimethacrylate/MTA-based root-end filling material (E-MTA) in comparison with white MTA Angelus (Angelus, Londrina, PR, Brazil) (W-MTA) and to evaluate the influence of the addition of calcium chloride (CaCl2) on these properties. METHODS: Polyethylene tubes filled with the materials were immersed in deionized water for the measurement of pH (digital pH meter) and calcium release (atomic absorption spectrophotometry). The evaluations were performed at 3 and 24 hours and 7, 15, and 30 days. Data were measured using 2-way repeated measures of variance followed by the Holm-Sidak method (P < .05). RESULTS: All materials presented a reduction in the pH and released calcium ions during the 30 days of the study. E-MTA showed a significantly lower calcium ion release capacity when compared with W-MTA (P < .05). The calcium release of E-MTA + 5% CaCl2 was similar to W-MTA (P > .05). CONCLUSIONS: The monomer bisphenol A ethoxylate dimethacrylate added to MTA formed a material with a lower capacity of calcium release than W-MTA despite maintaining a similar pH. However, the addition of CaCl2 improved the calcium release of this material.

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