Blood Distribution of SARS-CoV-2 Lipid Nanoparticle mRNA Vaccine in Humans.

Lipid nanoparticle mRNA vaccines are an exciting but emerging technology used in humans. There is limited understanding of the factors that influence their biodistribution and immunogenicity. Antibodies to poly(ethylene glycol) (PEG), which is on the surface of the lipid nanoparticle, are detectable in humans and boosted by human mRNA vaccination. We hypothesized that PEG-specific antibodies could increase the clearance of mRNA vaccines. To test this, we developed methods to quantify both the vaccine mRNA and ionizable lipid in frequent serial blood samples from 19 subjects receiving Moderna SPIKEVAX mRNA booster immunization. Both the vaccine mRNA and ionizable lipid peaked in blood 1-2 days post vaccination (median peak level 0.19 and 3.22 ng mL-1, respectively). The vaccine mRNA was detectable and quantifiable up to 14-15 days postvaccination in 37% of subjects. We measured the proportion of vaccine mRNA that was relatively intact in blood over time and found that the decay kinetics of the intact mRNA and ionizable lipid were identical, suggesting the intact lipid nanoparticle recirculates in blood. However, the decay rates of mRNA and ionizable lipids did not correlate with baseline levels of PEG-specific antibodies. Interestingly, the magnitude of mRNA and ionizable lipid detected in blood did correlate with the boost in the level of PEG antibodies. Furthermore, the ability of a subject's monocytes to phagocytose lipid nanoparticles was inversely related to the rise in PEG antibodies. This suggests that the circulation of mRNA lipid nanoparticles into the blood and their clearance by phagocytes influence the PEG immunogenicity of the mRNA vaccines. Overall, this work defines the pharmacokinetics of lipid nanoparticle mRNA vaccine components in human blood after intramuscular injection and the factors that influence these processes. These insights should be valuable in improving the future safety and efficacy of lipid nanoparticle mRNA vaccines and therapeutics.

Deposition of Human-Serum-Albumin-Functionalized Spheroidal Particles on Abiotic Surfaces: Reference Kinetic Results for Bioparticles.

Human serum albumin (HSA) corona formation on polymer microparticles of a spheroidal shape was studied using dynamic light scattering and Laser Doppler Velocimetry (LDV). Physicochemical characteristics of the albumin comprising the zeta potential and the isoelectric point were determined as a function of pH for various ionic strengths. Analogous characteristics of the polymer particles were analyzed. The adsorption of albumin on the particles was in situ monitored by LDV. The stability of the HSA-functionalized particle suspensions under various pHs and their electrokinetic properties were also determined. The deposition kinetics of the particles on mica, silica and gold sensors were investigated by optical microscopy, AFM and quartz microbalance (QCM) under diffusion and flow conditions. The obtained results were interpreted in terms of the random sequential adsorption model that allowed to estimate the range of applicability of QCM for determining the deposition kinetics of viruses and bacteria at abiotic surfaces.

Influencia de los revestimientos dentales en la adaptación marginal e interna de las cofias metálicas. Estudio in vitro / Influence of dental investments on the marginal and internal adaptation of metal copings. In vitro study

Objetivo. Evaluar la influencia de diferentes marcas de revestimientos dentales en la adaptación marginal e interna de las cofias metálicas. Método. La investigación fue in vitro, analítico, experimental y transversal; para ello, se confeccionaron 48 cofias metálicas, las cuales fueron cementadas en dientes humanos previamente tallados, luego las cofias fueron cortadas mesio-distalmente para evaluar su adaptación. La adaptación fue evaluada usando un estereomicroscopio Leica DM6000M. Para determinar si hay diferencia en la adaptación marginal e interna se empleó el análisis de varianza, la prueba de comparación múltiple y la prueba de Duncan. Adicionalmente, la prueba de Fisher, se utilizó para evaluar la adaptación total. Resultados. La mejor adaptación marginal e interna de las cofias metálicas lo presenta el revestimiento Fórmula 1 (Whipmix), seguido del Castorit súper C (Dentaurum) y Bellasun (Bego). Conclusión. Los revestimientos dentales no mostraron influencia en la adaptación marginal; sin embargo, si mostraron influencia en la adaptación interna.

Objective. To evaluate the influence of different brands of dental investments on the marginal and internal adaptation of metal copings. Method. The research was in vitro, analytical, experimental and transversal. For this, 48 metal copings were made, which were cemented on previously carved human teeth, then the copings were cut mesio-distally to evaluate their adaptation. The adaptation was evaluated using a Leica DM6000M stereomicroscope. To determine if there is a difference between marginal and internal adaptation; the analysis of variance, the multiple comparison test and the Duncan test were used. Furthermore, Fisher's exact test was used to evaluate the total adaptation. Results. The best marginal and internal adaptation of metal copings is presented by the Formula 1 coating (Whipmix), followed by Castorit super C (Dentaurum) and Bellasun (Bego). Conclusion. Dental investments did not show influence on marginal adaptation; however, they did show influence on internal adaptation.

Interactions Between Silver Nanoparticles and Culture Medium Biomolecules with Dose and Time Dependencies.

The interaction between silver nanoparticles (AgNPs) and molecules producing coronas plays a key role in cytotoxicity mechanisms. Once adsorbed coronas determine the destiny of nanomaterials in vivo, their effective deployment in the biomedical field requires a comprehensive understanding of the dynamic interactions of biomolecules with nanoparticles. In this work, we characterized 40 nm AgNPs in three different nutritional cell media at different molar concentrations and incubation times to study the binding mechanism of molecules on surface nanoparticles. In addition, their cytotoxic effects have been studied in three cell lineages used as tissue regeneration models: FN1, HUV-EC-C, RAW 264.7. According to the data, when biomolecules from DMEM medium were in contact with AgNPs, agglomeration and precipitation occurred. However, FBS medium proteins indicated the formation of coronas over the nanoparticles. Nonetheless, little adsorption of molecules around the nanoparticles was observed when compared to DMEM supplemented with 10% FBS. These findings indicate that when nanoparticles and bioproteins from supplemented media interact, inorganic salts from DMEM contribute to produce large bio-coronas, the size of which varies with the concentration and time. The static quenching mechanism was shown to be responsible for the fluorescence quenching of the bioprotein aggregates on the AgNPs surface. The calculated bioprotein-nanoparticle surface binding constants were on the order of 105 M-1 at 37 °C, with hydrophobic interactions driven by enthalpy and entropy playing a role, as confirmed by thermodynamic analysis. Cytotoxicity data showed a systematic degrowth in the viable cell population as the number of nanoparticles increased and the diameter of coronas decreased. Cytotoxic intervals associated with half decrease of cell population were established for AgNPs molar concentration of 75 µM for 24 h and 50 µM for 48 h. In summary, through the cytotoxicity mechanism of bio-coronas we are able to manipulate cells' expansion rates to promote specific processes, such inflammatory mechanisms, at different time instants.

Identified Small Open Reading Frame-Encoded Peptides in Human Serum with Nanoparticle Protein Coronas.

The low-molecular-weight proteins (LMWP) in serum and plasma are related to various human diseases and can be valuable biomarkers. A small open reading frame-encoded peptide (SEP) is one kind of LMWP, which has been found to function in many bioprocesses and has also been found in human blood, making it a potential biomarker. The detection of LMWP by a mass spectrometry (MS)-based proteomic assay is often inhibited by the wide dynamic range of serum/plasma protein abundance. Nanoparticle protein coronas are a newly emerging protein enrichment method. To analyze SEPs in human serum, we have developed a protocol integrated with nanoparticle protein coronas and liquid chromatography (LC)/MS/MS. With three nanoparticles, TiO2, Fe3O4@SiO2, and Fe3O4@SiO2@TiO2, we identified 164 new SEPs in the human serum sample. Fe3O4@SiO2 and a nanoparticle mixture obtained the maximum number and the largest proportion of identified SEPs, respectively. Compared with acetonitrile-based extraction, nanoparticle protein coronas can cover more small proteins and SEPs. The magnetic nanoparticle is also fit for high-throughput parallel protein separation before LC/MS. This method is fast, efficient, reproducible, and easy to operate in 96-well plates and centrifuge tubes, which will benefit the research on SEPs and biomarkers.

Facetas em resina composta com fechamento de diastemas para harmonização do sorriso: relato de caso / Composite resin veneers with diastema closure for smile harmonization: A case report / Facetas de resina compuesta con cierre de diastemas para harmonización de la sonrisa: Informe de caso

Introdução:A estética do sorriso é um aspecto valorizado pela sociedade atual, o que demanda que os profissionais de odontologia estejam atualizados sobre materiais dentários e novas técnicas para alcançar resultados estéticos restauradores de alta qualidade. A resina composta é frequentemente utilizada para simplificar a reabilitação oral, pois oferece facetas dentárias que combinam excelente estética e durabilidade. Objetivo:Este artigo tem como objetivo relatar um caso clínico de reabilitação estética utilizando facetas em resina composta com fechamento de diastemas.Relato de caso:Uma paciente do sexo feminino, com 24 anos de idade, procurou a clínica escola de odontologia com insatisfação em relação à estética do seu sorriso. A pacienteapresentava diastemas, restauração defeituosa e desproporção no tamanho dos dentes anteriores. O tratamento consistiu em um clareamento caseiro prévio, seguido pela confecção de facetas diretas em resina composta para fechamento dos diastemas e correção da desproporção dentária. Foram utilizados um Jig Estético e o software Digital Smile Design (DSD)para o planejamento, além de um mock-up em resina bisacrílica. Após a confecção das facetas, foi obtido um resultado estético final satisfatório. O caso incluiu um total de oito facetas,dos dentes 14 ao 24. Conclusão:O tratamento utilizando restaurações em resina composta proporcionou à paciente uma reabilitação estética, funcional e biológica (AU).

Introduction:Smile aesthetics is an aspect valued by today's society, which demands that dental professionals are up to date on dental materials and new techniques to achieve high-quality restorative aesthetic results. Composite resin is often used to simplify oral rehabilitation, as it offers dental veneers which combine excellent aesthetics and durability. Objective:This article aims to report a clinical case of aesthetic rehabilitation using composite resin veneers with diastema closure. Case report:A24-year-old female patient came to the dental school clinic with dissatisfaction regarding the aesthetics of her smile. The patient had diastemas, defective restoration and disproportionate anterior teeth size. The treatment consisted of prior at-home tooth bleaching, followed by creating direct composite resin veneers to close the diastemas and correct tooth disproportion. An Aesthetic Jig and the Digital Smile Design (DSD) software program were used for planning, in addition to a mock-up in bisacrylic resin. After treatment, a satisfactory final aesthetic result was obtained. The case included a total of eight veneers, from teeth 14 to 24. Conclusion:Treatment using composite resin restorations provided the patient with aesthetic, functional and biological rehabilitation (AU).

Introducción: La estética de la sonrisa es un aspecto valorado por la sociedad actual, hecho que demanda de los profesionales de odontología actualización constante sobre los materiales dentarios y nuevas técnicas para alcanzar resultados estéticos restauradores de altacualidad. La resina compuesta es frecuentemente utilizada para simplificar la rehabilitación oral, pues ofrece facetas dentarias que combinan excelente estética y durabilidad.Objetivo: Este artículo tiene como objetivo relatar un caso clínico de rehabilitación estética a partir de la utilización de facetas en resina compuesta con cierre de diastemas. Informe de caso: Una paciente, del sexo femenino, con 24 años de edad, buscó la clínica-escuela de odontología insatisfecha con la estética de su sonrisa. La paciente presentaba diastemas, restauración dentaria defectuosa y desproporción en el tamaño de los dientes anteriores. El tratamiento consistió en un blanqueamiento casero previo, seguido por la confección de facetas directas de resina compuesta para cierre de los diastemas y corrección de la desproporción dentaria. Fueron utilizados un Jig Estético y el software Digital Smile Design(DSD) para el planeamiento, además de un mock-upen resina bisacrílica. Tras la confección de las facetas, fue obtenido un resultado estético final satisfactorio. El caso incluyó un total de ocho facetas, de los dientes 14 al 24.Conclusión: El tratamiento a partir de restauraciones en resina compuesta proporcionó a la paciente una rehabilitación estética, funcional y biológica (AU).

Concentration-Dependent Layer Exfoliation of Black Phosphorus by Human Serum Albumin and Its Corresponding Biocompatibility Change.

Layered black phosphorus (LBP) is drawing increasing attention because of its excellent potential in biomedical applications. Properties and bioeffects of LBP depend on its layer number (LN). However, the variation of LN during applications, especially in organisms, is largely unknown. Herein, LBP is found to be exfoliated by human serum albumin (HSA) after the formation of protein coronas. The sorption of HSA on LBP exhibits multiple intermediate equilibrium and size-dependent capacity and is distinguished from traditional multilayer sorption. The loss of LN for LBP increases with the increase of HSA concentrations, e.g., 2, 4, and 6 layers of LBP are exfoliated at 35, 135, and 550 mg/L HSA, respectively. The energy distribution shows that at low HSA concentrations, exfoliation is mainly driven by electrostatic and hydrogen bond interactions. With middle or high HSA concentrations, exfoliation is mainly driven by p-π or hydrophobic interactions, respectively. Layer exfoliation causes the continuous emergence of an unsaturated LBP surface available for adsorbing further HSA, breaking previous sorption saturations. The complete exfoliation of LBP weakens cytotoxicity and promotes internalization to the A-549 cell line compared with pristine or less exfoliated LBP. This finding unveils the exfoliation mechanism of proteins toward LBP and is of benefit to evaluating application performance and biosafety of LBP.

Peptide Self-Assembly into Amyloid Fibrils at Hard and Soft Interfaces-From Corona Formation to Membrane Activity.

Peptides and proteins are exposed to a variety of interfaces in a physiological environment, such as cell membranes, protein nanoparticles (NPs), or viruses. These interfaces have a significant impact on the interaction, self-assembly, and aggregation mechanisms of biomolecular systems. Peptide self-assembly, particularly amyloid fibril formation, is associated with a wide range of functions; however, there is a link with neurodegenerative diseases, such as Alzheimer's disease. This review highlights how interfaces affect peptide structure and the kinetics of aggregation leading to fibril formation. In nature, many surfaces are nanostructures, such as liposomes, viruses, or synthetic NPs. Once exposed to a biological medium, nanostructures are coated with a corona, which then determines their activity. Both accelerating and inhibiting effects on peptide self-assembly have been observed. When amyloid peptides adsorb to a surface, they typically concentrate locally, which promotes aggregation into insoluble fibrils. Starting from a combined experimental and theoretical approach, models that allow for a better understanding of peptide self-assembly near hard and soft matter interfaces are introduced and reviewed. Research results from recent years are presented and relationships between biological interfaces, such as membranes and viruses, and amyloid fibril formation are proposed.

Presentation of infrequent clinical case of dental gemination of the permanent upper left lateral incisor

Introduction: Gemination is the division of a dental follicle that results in a tooth with two crowns, where the number of teeth in the arch does not vary. It constitutes an anomaly that is little diagnosed due to its presentation and therefore little treated, which requires an adequate study. Objective: To present an infrequent clinical case of dental gemination of the permanent upper left lateral incisor. Clinical case: 20-year-old patient with 30 weeks of gestational status treated for periodic review by appointment of her dentist. The intraoral examination revealed: the permanent upper left lateral incisor (tooth 22) with two crowns, one of which had lost the gingival wall and the other had second degree dental caries on the mesial side. Periapical radiography performed 1 year earlier showed tooth 22 with a partially divided pulp chamber and a broad, bifid, well-defined crown. Dental gemination of the permanent maxillary left lateral incisor was diagnosed. The geminated tooth was extracted, and the patient was referred to a dental prosthesis for rehabilitation. Conclusions: Dental gemination of the permanent upper left lateral incisor in a pregnant patient, constitutes an anomaly of the shape of the teeth that is infrequent in consultations.

Introducción: La geminación es la división de un folículo dentario que resulta en un diente de dos coronas, pero la cantidad de dientes de la arcada no varía. Constituye una anomalía poco diagnosticada por su presentación y por ende poco tratada, lo que necesita de un adecuado estudio. Objetivo: Presentar un caso clínico infrecuente de geminación dentaria del incisivo lateral superior izquierdo permanente. Caso clínico: Paciente de 20 años de edad, con 30 semanas de estado gestacional atendida para revisión periódica por citación de su estomatólogo. Al examen intraoral se detectó: el incisivo lateral superior izquierdo permanente (diente 22) con dos coronas, una de las cuales había perdido la pared gingival y la otra presentaba caries dental de segundo grado en cara mesial. La radiografía periapical realizada 1 año antes mostró el diente 22 con cámara pulpar parcialmente dividida y una corona ancha, bífida y bien definida. Se diagnosticó una geminación dentaria del incisivo lateral superior izquierdo permanente. Se realizó exodoncia del diente geminado y se remitió a la paciente a prótesis estomatológica para rehabilitación. Conclusiones: La geminación dentaria del incisivo lateral superior izquierdo permanente en una paciente embarazada es una anomalía de forma de los dientes poco frecuente en las consultas.

Mimicking Pseudo-Virion Interactions with Abiotic Surfaces: Deposition of Polymer Nanoparticles with Albumin Corona.

Adsorption of human serum albumin (HSA) molecules on negatively charged polystyrene microparticles was studied using the dynamic light scattering, the electrophoretic and the solution depletion methods involving atomic force microscopy. Initially, the physicochemical characteristics of the albumin comprising the hydrodynamic diameter, the zeta potential and the isoelectric point were determined as a function of pH. Analogous characteristics of the polymer particles were acquired, including their size and zeta potential. The formation of albumin corona on the particles was investigated in situ by electrophoretic mobility measurements. The size, stability and electrokinetic properties of the particles with the corona were also determined. The particle diameter was equal to 125 nm, which coincides with the size of the SARS-CoV-2 virion. The isoelectric point of the particles appeared at a pH of 5. The deposition kinetics of the particles was determined by atomic force microscopy (AFM) under diffusion and by quartz microbalance (QCM) under flow conditions. It was shown that the deposition rate at a gold sensor abruptly vanished with pH following the decrease in the zeta potential of the particles. It is postulated that the acquired results can be used as useful reference systems mimicking virus adsorption on abiotic surfaces.

Anti-PEG Antibodies Boosted in Humans by SARS-CoV-2 Lipid Nanoparticle mRNA Vaccine.

Humans commonly have low level antibodies to poly(ethylene) glycol (PEG) due to environmental exposure. Lipid nanoparticle (LNP) mRNA vaccines for SARS-CoV-2 contain small amounts of PEG, but it is not known whether PEG antibodies are enhanced by vaccination and what their impact is on particle-immune cell interactions in human blood. We studied plasma from 130 adults receiving either the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) mRNA vaccines or no SARS-CoV-2 vaccine for PEG-specific antibodies. Anti-PEG IgG was commonly detected prior to vaccination and was significantly boosted a mean of 13.1-fold (range 1.0-70.9) following mRNA-1273 vaccination and a mean of 1.78-fold (range 0.68-16.6) following BNT162b2 vaccination. Anti-PEG IgM increased 68.5-fold (range 0.9-377.1) and 2.64-fold (0.76-12.84) following mRNA-1273 and BNT162b2 vaccination, respectively. The rise in PEG-specific antibodies following mRNA-1273 vaccination was associated with a significant increase in the association of clinically relevant PEGylated LNPs with blood phagocytes ex vivo. PEG antibodies did not impact the SARS-CoV-2 specific neutralizing antibody response to vaccination. However, the elevated levels of vaccine-induced anti-PEG antibodies correlated with increased systemic reactogenicity following two doses of vaccination. We conclude that PEG-specific antibodies can be boosted by LNP mRNA vaccination and that the rise in PEG-specific antibodies is associated with systemic reactogenicity and an increase of PEG particle-leukocyte association in human blood. The longer-term clinical impact of the increase in PEG-specific antibodies induced by lipid nanoparticle mRNA vaccines should be monitored. It may be useful to identify suitable alternatives to PEG for developing next-generation LNP vaccines to overcome PEG immunogenicity in the future.

Rehabilitación estética con coronas de resina personalizadas utilizando encerado digital en paciente pediátrico: informe de caso / Aesthetic rehabilitation with customized resin crowns using digital wax-up in pediatric patient: a case report

Resumen Introducción: El presente informe de caso clínico se enfoca en el diagnóstico y tratamiento para la rehabilitación de la dentición temporal en el sector anterosuperior utilizando tecnología CAD-CAM. Objetivo: Proponer una alternativa para mitigar el margen de error y tiempo de trabajo en el paciente pediátrico, reintegrando la estética y funcionalidad en la cavidad oral. Métodos: Se describe el caso de un paciente de sexo masculino de 6 años que acudió a la clínica universitaria de la Universidad UTE con lesiones cariosas extensas en sus dientes anterosuperiores y su rehabilitación a través de la utilización de coronas personalizadas de resina mediante un encerado digital realizado en CAD-CAM. Resultados: El tratamiento efectuado en el niño fue satisfactorio, se evidenció una mejoría en la dimensión vertical e incremento en la estética dental y facial, mejorando su aspecto y autoestima después de la rehabilitación. Conclusión: La utilización del encerado digital en pacientes pediátricos podría ser una alternativa que permita reducir el tiempo de trabajo del tratamiento en una rehabilitación estética dental.

Abstract Introduction: This case report focuses on the diagnosis and treatment for the rehabilitation of the primary dentition in the anterosuperior sector using CADCAM technology. Objective: To propose an alternative to mitigate the margin of error and working time in pediatric patients, reintegrating esthetics, and functionality in the oral cavity. Methods: We describe the case of a 6-year-old male patient who came to the clinic of Universidad UTE with extensive carious lesions in his anterosuperior teeth and his rehabilitation using personalized resin crowns by means of a digital waxup performed in CAD-CAM. Results: The treatment performed on the child was satisfactory, there was an improvement in the vertical dimension and an increase in dental and facial esthetics, improving his appearance and self-esteem after the rehabilitation. Conclusión: The use of digital wax-up in pediatric patients could be an alternative that allows the treatment time to be reduced in esthetic dental rehabilitation.

Accelerated artificial aging and color stability in resin-based cements / Envejecimiento artificial acelerado y estabilidad de color de medios de fijación a base de resinas

ABSTRACT The aim of this study was to determine color change after accelerated artificial ageing (AAA) of different composite cements that are used with veneers. Five cylindrical test specimens, 15 mm in diameter and 2 mm thick, were made from a single layer of each of the following: RelyX Veneer 3M ESPE (RX), Paracore White Coltene (PC), Solocem White Opaque Coltene (SO), Resin Duo Cement Densell (DC), Panavia V5 Paste Kuraray Noritake (PA) and Panavia F2.0 Kuraray Noritake (PF) (30 specimens altogether). The specimens were light cured following manufacturers' instructions using a Coltolux LED (Coltene) unit. Initial color was determined using an Easyshade - Vita Zahnfabrik Spectrophotometer. Then, the specimens were subjected to AAA for two weeks (336 hours) with cycles of 4 hours of UV light at 60 °C and 4 hours of vapor condensation at 50 °C, successively, after which color was recorded again. Color change was determined for each specimen according to the difference in shade on the Vita scale before and after AAA. Results were analyzed using Kruskal Wallis test. Mean and standard deviation for each group were: RX 8.40 (1.52); PC 8.60 (3.13); SO 6.40 (3.51); DC 10.00 (0.00); PA 7.60 (3.29); PF 2.00 (0.00). The Kruskal Wallis test showed significant difference for material (p<0.05), and comparison of means showed difference between Panavia F2.0 and the other materials. A table providing equivalence between the Vita Classic and CIELAB scales was used to transfer the recorded colors to the CIELAB scale, and the color difference ΔE was calculated for each group, where ΔL, Δa and Δb are the differences in the L, a and b values before and after the AAA. The mean and standard deviation were analyzed statistically by the ANOVA test and Tukey's test. Mean and standard deviation for each group were: RX 14.94 (2.02); PC 14.51 (4.02); SO 12.08 (4.53); DC 16.31 (0.00); PA 10.9 (3.38); PF 7.24 (0.00). The ANOVA test showed significant difference for material (p<0.05). Tukey's test showed two groups (PF-DC, RX, PA). Under the experimental conditions of this study, it can be concluded that accelerated ageing significantly affects the color stability of the resin based cements tested.

RESUMEN El objetivo de este trabajo fue determinar el cambio de coloración de distintos medios de fijación a base de resinas con indicación para carillas estéticas luego de someterse al envejecimiento artificial acelerado (AAA). Se confeccionaron 30 probetas cilíndricas de 15 mm de diámetro y 2 mm de espesor con RelyX Veneer 3M ESPE (RX), Paracore White Coltene (PC), Solocem White Opaque Coltene (SO), Resin Duo Cement Densell (DC), Panavia V5 Paste Kuraray Noritake (PA) y Panavia F2.0 Kuraray Noritake (PF) de una sola capa de material. Se polimerizaron según las indicaciones del fabricante con unidad de curado Coltolux LED (Coltene). Cada grupo quedó conformado con 5 probetas de cada material. Se tomó el color con el espectrofotómetro Easyshade de Vita Zahnfabrik. A continuación, se sometieron a AAA por dos semanas (336 horas) con ciclos de 4 horas de radiaciones ultravioletas a 60°C Y 4 horas de condensación de vapor de agua a 50°C sucesivamente. Una vez terminado este proceso se volvió a registrar el color. El cambio de color se evaluó dentro de la escala de color, ordenada en función del valor. El dato registrado fue la diferencia en la posición inicial y final en esta escala. Los resultados obtenidos para cada grupo fueron analizados por medio de la prueba de Kruskal Wallis. Los valores de media y desvío estándar de cada grupo fueron: RX 8,40 (1,52); PC 8,60 (3,13); SO 6,40 (3,51); DC 10,00 (0,00); PA 7,60 (3,29); PF 2,00 (0,00). El análisis con la prueba de Kruskal Wallis mostró diferencia significativa para el factor material (p<0.05) y la comparación de medias mostró diferencia entre PF y el resto de los materiales. Por otra parte, con una tabla de equivalencia entre los colores en escala de Vita Classic y CIE Lab, se hicieron el pasaje de los valores registrados a la escala de CIE Lab y se calculó la diferencia de color ΔE de cada grupo antes y después del AAA. La media y el desvío estándar fueron analizados estadísticamente por el test de ANOVA y prueba de Tukey. Los valores de media y desvío estándar de cada grupo fueron: RX 14,94 (2,02); PC 14,51 (4,02); SO 12,08 (4,53); DC 16,31 (0,00); PA 10,9 (3,38); PF 7,24 (0,00). En la evaluación de los resultados con ANOVA se encontró diferencia significativa entre los materiales evaluados (p<0,05). La comparación de medias con prueba de Tukey mostró la presencia de dos grupos (PF-DC, RX, PA). En las condiciones experimentales de este trabajo puede concluirse que el envejecimiento acelerado afecta significativamente la estabilidad de color de los cementos utilizados en este trabajo.

Change of Cell Toxicity of Food-Borne Nanoparticles after Forming Protein Coronas with Human Serum Albumin.

Nanoparticles (NPs) can form protein coronas with plasma proteins after entering the biological environment due to their surface adsorption ability. In this study, the effects of protein coronas of roast squid food-borne nanoparticles (FNPs) with human serum albumin (HSA) on the HepG-2 and normal rat kidney (NRK) cells were investigated. The hydrodynamic diameters of the HSA and HSA-FNPs were 8 and 13 nm, respectively. The cytotoxicity and cell membrane damage of FNPs to HepG-2 cells increased with the increase of roasting temperature. The presence of 4.78 × 10-3 mol/L FNPs increased the numbers of cellular necrosis and prolonged the G2 phase of the cell cycle. The formation of protein coronas of squid FNPs mitigated the autophagy phenomenon by FNPs on HepG-2 cells. Moreover, protein coronas reduced the mitochondrial membrane potential in the HepG-2 and NRK cells and the production of reactive oxygen species caused by FNPs. The abnormal contents of oxidative stress indicators such as glutathione, superoxide dismutase, malondialdehyde, and catalase in HepG-2 and NRK cells induced by FNPs were alleviated due to the presence of HSA. These results suggested that the protein coronas formed by HSA on FNPs mitigated the cytotoxicity compared with the bare FNPs, thus providing insights into the interaction of squid FNPs with HSA.

Endocorona, un enfoque diferente en rehabilitación oral

RESUMEN Introducción: Con el avance de la tecnología adhesiva, nuevas técnicas y materiales restauradores están siendo utilizados para el tratamiento de dientes endodonciados, por ello, las endocoronas son una alternativa clínica para su tratamiento. La ventaja de esta restauración es que tiene mejores características macro retentivas, requiere menor tiempo clínico y de laboratorio. Objetivo: Proporcionar información bibliográfica actual sobre esta nueva alternativa para aplicar una nueva guía en rehabilitación oral con el uso de la endocorona mediante una revisión de la literatura. Método: Se realizó una revisión bibliográfica detallada, con la consideración de artículos originales o casos clínicos que incluían información relacionada a las restauraciones de tipo endocorona. La búsqueda se efectuó en las bases de datos PubMed, SciELO, Science Direct, Elsevier y Google Académico. Resultados: Las restauraciones de tipo endocorona son un monobloque único que devuelve la anatomía completa de la corona dental, la cual aprovecha la cámara pulpar para así lograr una mayor adhesión y macro retención mecánica. Este enfoque restaurador proporciona una función adecuada y estética, así como la integridad biomecánica de las estructuras no vitales. Conclusiones: Actualmente en la Odontología moderna se emplea el término de mínima intervención, conservando en su mayor cantidad posible el tejido dental de manera que los dientes tengan mayor funcionalidad, por ello las endocoronas son una opción segura y con buen pronóstico a largo plazo en rehabilitación oral para tratar piezas endodonciadas, debido a que es un procedimiento técnicamente más conservador, estético, sencillo y de menor costo.

ABSTRACT Introduction: With the advancement of adhesive technology, new techniques and restorative materials are being used for the treatment of root canals; therefore endocrowns are a clinical alternative for their treatment. The advantage of this restoration is that it has better macro retentive characteristics, requires less clinical and laboratory time. Objective: To provide current bibliographic information on this new alternative to apply a new guide in oral rehabilitation with the use of endocrown through a literature review. Method: A detailed bibliographic review was carried out, with the consideration of original articles or clinical cases that included information related to endocrown-type restorations. The search was carried out in the databases PubMed, SciELO, Science Direct, Elsevier and Google Scholar. Results: Endocrown restorations are a single monoblock that rebuilds the complete anatomy of the dental crown, which takes advantage of the pulp chamber to achieve greater adhesion and macro mechanical retention. This restorative approach provides adequate function and aesthetics, as well as the biomechanical integrity of non-vital structures. Conclusions: The term minimal intervention is currently very used in modern dentistry, preserving the dental tissue as much as possible so that the teeth have greater functionality. Endocrowns are a safe option with a good long-term prognosis in oral rehabilitation to treat root canals, because it is a technically more conservative, aesthetic, simple and lower-cost procedure.

RESUMO Introdução: Com o avanço da tecnologia adesiva, novas técnicas e materiais restauradores estão sendo utilizados para o tratamento de dentes endodônticos, portanto os endocrowns são uma alternativa clínica para seu tratamento. A vantagem dessa restauração é que ela apresenta melhores características macro retentivas, requer menos tempo clínico e laboratorial. Objetivo: Fornecer informações bibliográficas atuais sobre esta nova alternativa de aplicação de um novo guia na reabilitação oral com o uso de endocrown por meio de uma revisão da literatura. Método: Foi realizada uma revisão bibliográfica detalhada, considerando artigos originais ou casos clínicos que incluíam informações relacionadas a restaurações do tipo endocrown. A busca foi realizada nas bases de dados PubMed, SciELO, Science Direct, Elsevier e Google Scholar. Resultados: As restaurações do tipo endocrown são um único monobloco que devolve a anatomia completa da coroa dentária, que aproveita a câmara pulpar para obter maior adesão e retenção macromecânica. Esta abordagem restauradora fornece função e estética adequadas, bem como a integridade biomecânica de estruturas não vitais. Conclusões: Atualmente na odontologia moderna é utilizado o termo de intervenção mínima, preservando-se o tecido dentário o máximo possível para que os dentes tenham maior funcionalidade, portanto endocrowns são uma opção segura e com bom prognóstico em longo prazo na reabilitação oral para tratamento da endodontia dentes, por ser um procedimento tecnicamente mais conservador, estético, simples e de menor custo.

Deposition of Polymer Particles with Fibrinogen Corona at Abiotic Surfaces under Flow Conditions.

The deposition kinetics of polymer particles with fibrinogen molecule coronas at bare and poly-L-lysine (PLL) modified mica was studied using the microfluid impinging-jet cell. Basic physicochemical characteristics of fibrinogen and the particles were acquired using dynamic light scattering and the electrophoretic mobility methods, whereas the zeta potential of the substrates was determined using streaming potential measurements. Subsequently, an efficient method for the preparation of the particles with coronas, characterized by a controlled fibrinogen coverage, was developed. This enabled us to carry out measurements, which confirmed that the deposition kinetics of the particles at mica vanished at pH above 5. In contrast, the particle deposition of PLL modified mica was at maximum for pH above 5. It was shown that the deposition kinetics could be adequately analyzed in terms of the mean-field approach, analogously to the ordinary colloid particle behavior. This contrasts the fibrinogen molecule behavior, which efficiently adsorbs at negatively charged substrates for the entire range pHs up to 9.7. These results have practical significance for conducting label-free immunoassays governed by the specific antigen/antibody interactions.

Esthetic rehabilitation with indirect resin on anterior teeth: a clinical report / Reabilitação estética com resina indireta em dentes anteriores: um relato clínico / Rehabilitaciónestética con resina indirecta en dientes anteriores: reporte clínico

Introduction:The aesthetic rehabilitation of endodontically treated teeth depends on the destruction degree of the crown, the bone support, type of prosthesis, andchewing forces. In these cases, indirect restorations with composite resins are an excellent alternative. The indirect composite resins have improved physical and mechanical properties due toincorporatingof inorganic fillersand multifunctional monomers. These components offer a greater bonding strength to the indirect restorations, which is advantageous for further rehabilitations with ceramic crowns. Objective:To present an aesthetic rehabilitation of anterior teeth with indirect composite resin as a feasible and less expensive treatment alternative.Case Report:Upon clinical examination, extensive and deficient restorations were observed in the upper anterior teeth. The proposed treatment plan was the aesthetic rehabilitation of endodontically treated teeth with indirect restorations using ceromer.Conclusions:This treatment represented an excellent alternative for aesthetic rehabilitation of endodontically treated teeth in cases of great dental crown destruction or small dental absences (AU).

Introdução:A reabilitação estética de dentes tratados endodonticamente depende do grau de destruição da coroa, do dente em questão, do suporte ósseo, do tipo de prótese e dos tipos de forças a que esses dentes serão submetidos. As resinas compostas indiretas apresentam propriedades físicas e mecânicas aprimoradas graças à incorporação de componentes inorgânicos e monômeros multifuncionais com maior número de pontos de união, tornando-os capazes de solucionar os problemas em que seriam indicadas restaurações cerâmicas. Objetivo:Apresentar um relato de caso clínico de uma reabilitação estética de dentes anteriores com resina composta indireta como alternativa de tratamento viável e de menor custo.Relato de Caso:Ao exame clínico foram observadas restaurações amplas e deficientes nos dentes anteriores superiores. O plano de tratamento proposto reabilitação estética dos elementos dentários com cerômeros.Conclusões:Este tratamento representou uma opção viável e demenor custo que pode ser utilizado tanto em situações de grande destruição dentária como em pequenas ausências dentárias, em substituição às restaurações de cerâmica (AU).

Introducción: La rehabilitación estética de los dientes tratados endodónticamente depende del grado de destrucción de la corona, el diente en cuestión, el soporte óseo, el tipo de prótesis y los tipos de fuerzas a las que estos dientes serán sometidos. Las resinas compuestas indirectas tienen propiedades físicas y mecánicas mejoradas gracias a la incorporación de componentes inorgánicos y monómeros multifuncionales con mayor número de puntos de unión, lo que las hace capaces de resolver los problemas en los que estarían indicadas las restauraciones cerámicas. Objetivo: Presentar un caso clínico de rehabilitación estética de dientes anteriores con resina compuesta indirecta como alternativa de tratamiento viable y menos costosa. Reporte de Caso:En el examen clínico, se observaron restauraciones extensas y deficientes en los dientes anteriores superiores. El plan de tratamiento propuesto para la rehabilitación estética de elementos dentales con cerómeros. Conclusiones:Este tratamiento representó una opción viable y menos costosa que se puede utilizar tanto en situaciones de gran destrucción dentaria como en pequeñas ausencias dentales, en sustitución de las restauraciones cerámicas (AU).

Mimetización de corona cerámica libre de metal de un incisivo central superior. Reporte de caso / Mimicry of metal-free ceramic crown of an upper central incisor. Case report

Actualmente, la estética dental presenta un papel relevante dentro de las relaciones interpersonales y la autoestima de los pacientes, es por eso que la demanda de tratamientos estéticos y conservadores son cada vez más frecuentes en la consulta dental, esta demanda compromete a los profesionales a una mayor preparación para identificar los procedimientos más adecuados a ejecutarse. Para el odontólogo es un reto conseguir una completa armonización e integración de los tratamientos efectuados en el sector anterior y más aún cuando se requiere reemplazar un único elemento dentario. El presente reporte de caso tiene por objetivo describir un caso de rehabilitación de alta complejidad de un incisivo central superior fracturado, cuyas características de color y forma fueron recrea- das a través de un correcto intercambio de información entre el odontólogo y el técnico dental, obteniendo una corona de disilicato de litio con una excelente mimetización.

Nowadays, dental aesthetics has a relevant role within interpersonal relationships and the self-esteem of patients, that is the reason the demand for aesthetic and conservative treatments are more frequent in dental practice, this demand commits professionals to a greater preparation, in order to identify the most appropriate procedures to be executed. For the dentist it is a challenge to achieve a complete harmonization and integration of the treatments carried out in the anterior sector and even more when it is necessary to replace a single dental element. The objective of this case report is to describe a highly complex rehabilitation case of a fractured upper central incisor, whose color and shape characteristics were recreated through a correct exchange of information between the dentist and the dental technician, obtaining a lithium disilicate crown with excellent mimicry.

Uso de coronas de acetato para la confección de coronas de resina en dientes primarios: Reporte de caso

Siendo una de las opciones de restauración el uso de la técnica de coronas de acetato, se optó por ésta debido a los resultados estéticos que ofrece y por sus pocos pasos clínicos. Cumpliendo así con nuestro objetivo de mantener la integridad de las piezas y conservarlas en su espacio, mediante el uso de coronas de resina confeccionadas bajo esta técnica. La metodología utilizada fue el reporte de caso clínico en paciente de 2 años 09 meses de género masculino con diagnóstico caries dental, donde se realizó coronas de resina con la técnica de coronas de acetato. Para la evaluación clínica a los 12 meses se usaron los criterios de evaluación para las restauraciones directas e indirectas según la World Dental Federation. No presentaron fractura y recidiva de caries. Las coronas confeccionadas con ésta técnica fueron bien aceptadas debido a sus resultados imperceptibles, bajo costo y menor tiempo clínico. Por lo que el uso de ésta técnica sería una opción de tratamiento, pero se requieren más estudios para determinar sus ventajas a largo plazo.

Resistencia a la fractura de coronas dentales fabricadas análogamente vs tecnología cad-cam. Estudio In vitro / Fracture resistance of analogally made dental crowns vs cad-cam technology. In vitro study

Resumen Antecedentes. La resistencia a la fractura de las coronas puede tener influencia en su ocurrencia, de acuerdo con el método de fabricación usado, ya sea análogamente o por medio de tecnología Cad-Cam. Objetivo. Comparar la resistencia a la fractura de las coronas individuales realizadas por dos métodos de fabricación, bajo diseño asistido por ordenador y fabricación computarizada (CAD-CAM) e inyectadas. Método. Estudio in vitro. Tamaño de la muestra 20 coronas en dos grupos: 10 coronas bajo tecnología CAD-CAM y 10 coronas inyectadas. Fueron sometidas a cargas compresivas en una máquina de ensayos universal, con una velocidad de 1mm/min y una carga de celda de 5kN hasta obtener la fractura máxima de estas. Los datos se analizaron estadísticamente utilizando las pruebas Shapiro Wilk, Mann Whitney p=0,05. Resultados. Las coronas fabricadas por Cad-Cam obtuvieron un mínimo de 602,5 Newton y un máximo de 1093 Newton, mientras que las coronas fabricadas análogamente obtuvieron un mínimo de 525,2 Newton y un máximo de 1773 Newton en el experimento con la máquina de ensayo universal para lograr su fractura. Se obtuvo una diferencia significativa en la prueba de resistencia a la factura entre ambos métodos de fabricación (p <0,001). Conclusión. Las coronas de Disilicato de litio Prensadas obtuvieron una mayor resistencia a la fractura que las coronas fabricadas via CAD-CAM.

Abstract Background. The fracture resistance of the crowns may have an influence on their appearance, according to the method of making them, either analogously or by means of Cad-Cam technology. Objective. To compare the resistance to the fracture of the individual crowns made by two manufacturing methods, under computer-aided design and computerized manufacturing (CAD-CAM) and injected. Methods. In vitro study. Sample size 20 crowns in two groups: 10 crowns using CAD-CAM technology and 10 crowns injected. Crowns were subjected to compressive loads in a universal testing machine, with a speed of 1mm / min and a cell load of 5kN until obtaining the maximum bill for these. Data were statistically analyzed using the Shapiro Wilk tests, Mann Whitney p = 0.05. Results. Crowns manufactured by Cad-Cam obtained a minimum of 602.5 Newton and a maximum of 1093 Newton, while the crowns manufactured analogously obtained a minimum of 525.2 Newton and a maximum of 1773 Newton in the experiment with the machine Universal test to achieve their fracture. A significant difference was obtained in the invoice resistance test between both manufacturing methods (p <0.001). Conclusion. Pressed Lithium Disilicate crowns obtained higher fracture resistance than crowns under design and manufacturing by computer (CAD-CAM).