Search results for "Crown"

Goal-directed junior ultrasound training in quantitative measurement of crown-rump length and fetal nuchal translucency: evaluation of a specific tra…

2015

Structural effects of macrocyclic compounds and their partition in sodium dodecylsulphate aqueous solutions

2003

The partition of 1,4,7,10,13,16-esaoxacyclooctadecane (18C6), 4,7,13,16-tetraoxa-1,10-diazacyclooctadecane (2.2), 2,5,8,11,14,17-esaoxabicyclo[16.4.0]dicosane (B18C6) and 2,5,8,15,18,21-esoxatricyclo[20.4.0.09.14]esacosane (Cy218C6) in sodium dodecyl sulfate (SDS) aqueous solutions and their effect on the structure of surfactant aggregates has been investigated by small-angle neutron scattering. Results from data analysis have shown that by increasing macrocycle concentration the SDS micelles dimensions reduce for all systems investigated. At the same time information on macrocycles partition between the micellar and the continuous phase have been obtained. It was found that an appreciable …

Front Cover: Filling the Gap in the Metallacrown Family: The 9‐MC‐3 Chromium Metallacrown (Chem. Eur. J. 13/2021)

2021

Credit, Debt and FInances of the Queen's Household in the Crown of Aragon at the End of the Fourteenth Century. The Agreement between the Queen Viola…

2018

A finales del siglo XIV la tesorería de la reina Violante de Bar padecía de un fuerte endeudamiento que imposibilitaba prácticamente cualquier pago, por lo que se decidió cambiar la dirección de la gestión económica de la Casa de la reina. En el presente artículo analizaremos las estrategias para solucionar el problema del endeudamiento, mediante la edición y el análisis de los excepcionales capítulos y memoriales firmados por la reina Violante y su nuevo tesorero, Berenguer de Cortilles, uno de sus mayores acreedores privados. At the end of the Fourteenth century, Queen’s treasury in the Crown of Aragon suffered from a heavy debt that made virtually impossible any ordinary payment. As a re…

Per camins inussitats i sendes molt apartades. Contrabando de seda valenciana hacia Castilla durante la segunda mitad del siglo XVI

2015

Este artículo analiza la intensa corriente de contrabando de seda valenciana hacia Castilla, que se desarrolló durante la segunda mitad del siglo XVI. Entre otros factores, la creación del nou imposit de la seda en 1552 incentivó esta actividad ilícita, que llegó a convertirse en un modo de vida en las principales regiones productoras (especialmente la Ribera del Júcar) y un motivo constante de litigio para las autoridades, incapaces de frenar este tráfico ilícito. La política fiscal valenciana y el auge del contrabando de seda a Toledo lastró la sedería valenciana durante esta centuria, ya que dificultó el abastecimiento de materia prima de los telares de la ciudad de Valencia. Del mismo m…

Tooth-implant connection in removable denture.

2016

When the patient cannot be rehabilitated with a fixed denture, or when he does not succeed in adapting to a traditional removable denture, a possible alternative solution consists in the use of a limited number of implants, placed in strategic positions in the arches of the patient, and subsequently connected to their residual teeth. The aim of this review is to evaluate the progress made on connections between teeth and implants in removable denture, to analyze their advantages and disadvantages and to compare the survival rate, both of the teeth and of the implants used as abutments, present in the various studies taken into examination, with the aim of being able to evaluate the effectiv…

Retentive strengths of cast gold crowns using glass ionomer, compomer, or resin cement

1998

The retention forces of a newly developed compomer cement (Dyract Cem), a glass ionomer cement (Ketac Cem Aplicap), and a resin cement (F21) were examined.Cemented cast gold crowns were removed along the path of insertion with a Zwick universal testing device. The impact of both a cured and a noncured additional bonding layer that were applied to the inner surface of the crowns was examined across the Dyract Cem group.The mean adhesive strength was measured at 2.36 +/- 0.69 N/mm2 in the Ketac Cem group, at 0.60 +/- 0.28 N/mm2 in the F21 group, and at 1.85 +/- 0.94 N/mm2 in the Dyract Cem group, respectively. The application of an additional bonding layer to the inner surface of the crowns d…

In vitro retentive strength of zirconium oxide ceramic crowns using different luting agents

2005

Statement of problem In contrast to gold crowns, in vitro determination of the retentive strength of all-ceramic crowns is more difficult because components allowing connection to testing apparatus are not as easily integrated into the all-ceramic material. Nevertheless, retentive strength data are crucial for obtaining information about the potential clinical performance of luting cements for all-ceramic restorations. Therefore, a new in vitro model was necessary to evaluate the retentive strength of all-ceramic crowns. Purpose The purpose of this in vitro study was to determine the retentive strength of 4 resin-cement systems, a compomer, a glass-ionomer cement, a resin-modified glass-ion…

Premolars restored with posts of different materials: fatigue analysis

2011

Previous works studied the effect of the material and the dimensions of the post on the biomechanical performance (fracture strength and stress distribution) of restored teeth, under static loads. The aim of this work was to study the effect of the post material (glass fibre and stainless steel) on restored teeth, which have the final crown, under dynamic conditions. The use of a biomechanical model, including a fatigue analysis from FEA, is presented as a powerful method to study the effect of the material of the intraradicular post. The inclusion of the fatigue analysis allows for a more realistic study that takes into account the dynamic nature of masticatory forces. At the same time, th…

Luting of ceramic crowns with a self-adhesive cement: Effect of contamination on marginal adaptation and fracture strength

2012

Objectives: This study evaluated the percentages of continuous margins (%CM) and fracture strength (FS) of crowns made out from blocs of leucite-reinforced ceramic (IPS Empress CAD) and luted with a representative self-adhesive cement (RelyX Unicem) under four contaminating agents: saliva, water, blood, a haemostatic solution containing aluminium chloride (pH= 0.8) and a control group with no contamination. Study Design: %CM at both tooth-cement (TC) and cement-crown (CC) interfaces were determined before and after a fatigue test consisting of 600’000 chewing loads and 1’500 temperature cycles changing from 5º C to 50º C. Load to fracture was recorded on fatigued specimens. Kruskal-Wallis t…