Search results for " resin"
showing 10 items of 268 documents
Effect of different concentrations of specific inhibitor of matrix metalloproteinases on the shear bond strength of self-adhesive resin cements to de…
2017
Background Considering the probability of chemical and enzymatic reactions between matrix metalloproteinases (MMPs) in the dentin structure and their specific inhibitors, the aim of the present study was to evaluate the effect of different concentrations of specific inhibitor of MMPs (galardin) on the shear bond strength of self-adhesive resin cements to dentin. Material and Methods Forty-eight sound human premolars were mounted in self-cured acrylic resin after removal of the enamel on the buccal and lingual surfaces. The dentin surfaces achieved were polished and prepared with 600-grit silicon carbide paper. The samples were divided into 3 groups (n=16) based on the concentration of galar…
Re-examining the rare and the lost : a review of fossil Tortricidae (Lepidoptera)
2018
We re-evaluate eleven fossils that have previously been assigned to the family Tortricidae, describe one additional fossil, and assess whether observable morphological features warrant confident assignment of these specimens to this family. We provide an overview of the age and origin of the fossils and comment on their contribution towards understanding the phylogeny of the Lepidoptera. Our results show that only one specimen, Antiquatortia histuroides Brown & Baixeras gen. and sp. nov., shows a character considered synapomorphic for the family. Six other fossils ( Electresia zalesskii Kusnezov, 1941; Tortricidrosis inclusa Skalski, 1973; Tortricites skalskii Kozlov, 1988; Tortricibaltia d…
Bifunctional poly(acrylamide) hydrogels through orthogonal coupling chemistries
2019
Biomaterials for cell culture allowing simple and quantitative presentation of instructive cues enable rationalization of the interplay between cells and their surrounding microenvironment. Poly(acrylamide) (PAAm) hydrogels are popular 2D-model substrates for this purpose. However, quantitative and reproducible biofunctionalization of PAAm hydrogels with multiple ligands in a trustable, controlled, and independent fashion is not trivial. Here, we describe a method for bifunctional modification of PAAm hydrogels with thiol- and amine- containing biomolecules with controlled densities in an independent, orthogonal manner. We developed copolymer networks of AAm with 9% acrylic acid and 2% N-(4…
Transferability of PCR-based diagnostic protocols: An international collaborative case study assessing protocols targeting the quarantine pine pathog…
2019
Producción Científica
Applications of confocal laser scanning microscopy to dental bonding.
1998
The introduction of confocal laser scanning microscopy (CLSM) has provided a valuable new technique for the visualization of bonding structures such as a hybrid layer in dentin (Watson, 1989, 1991), In the case of seven commercially-available dentin bonding systems, it could be demonstrated that the CLSM renders considerably more detailed information than the SEM because of its nondestructive nature and because of the possibility of a distinction between components of bonding agents. With most of the bonding systems, measurements of the thickness of the hybrid layer could be carried out when the primer component was labeled with rhodamine B. It was found that this thickness is significantl…
The application of casein phosphopeptide and amorphous calcium phosphate with fluoride (CPP-ACPF) for restoring mineral loss after dental bleaching w…
2018
Abstract Objective To conduct an in vitro evaluation of the effect of casein-phosphopeptide and amorphous calcium phosphate with fluoride [CPP-ACPF] upon the calcium [Ca] and phosphorus [P] composition and morphology of dental enamel and dentin after the application of two bleaching agents: 37.5% hydrogen peroxide [HP]) and 35% carbamide peroxide [CP]. Materials and methods The crowns of 40 extracted human teeth were divided into four groups (n = 10 each). The crowns were sectioned along the cervical-incisal axis, and each half was embedded in acrylic resin, leaving a window 3 mm in diameter to explore the enamel or dentin (according to the study group involved). Groups 1a and 1b correspond…
Longevity and risk factors of post restorations after up to 15 years: A practice-based study.
2020
Abstract Introduction The aims of this multicenter, practice-based cohort study were to evaluate the success and survival of endodontically treated teeth with post restorations (ETT+Ps) and to analyze factors associated with the longevity of ETT+Ps. Methods Eight general dental practitioners each placed up to 27 ETT+Ps without any restriction to post materials or dimensions. Only incisors, canines, and premolars were included. At the last follow-up visit, ETT+Ps were considered as successful if the post and the initially placed definitive restoration were sufficient, whereas ETT+Ps were considered as survived if the post was still in function. Multilevel Cox proportional hazards models were…
Absorption kinetics and swelling stresses in hydrothermally aged epoxies investigated by photoelastic image analysis
2015
Abstract The present work proposes an experimental optical methodology able to measure the transient swelling stresses induced by the water uptake ageing of polymers. In particular, the work describes the implementation of a Photoelastic technique to quantify internal stresses arising during the hydrothermal ageing of cast epoxy samples. The material investigated is a model DGEBA/DDS epoxy system. Curing and post-curing cycles have been optimised in order to obtain a fully cured, high T g , and completely stress free initial condition. Rectangular beam samples were then left in a hydrothermal bath at 90 °C, and regularly monitored by gravimetric and photoelastic analyses. The quantitative e…
Hydrothermal Aging of an Epoxy Resin Filled with Carbon Nanofillers
2020
The effects of temperature and moisture on flexural and thermomechanical properties of neat and filled epoxy with both multiwall carbon nanotubes (CNT), carbon nanofibers (CNF), and their hybrid components were investigated. Two regimes of environmental aging were applied: Water absorption at 70 °
Intercalated cells as a probable source for the development of renal oncocytoma
1988
Renal oncocytoma is a distinct type of epithelial tumor said to arise from the collecting duct system. Here we show that in nine of ten oncocytomas the tumor cells expressed an analog of the erythrocyte anion exchanger band 3. In the normal kidney band 3 is confined to the basolateral surface of the majority of intercalated cells which comprise up to 50% of the cortical collecting duct epithelium. Carbonic anhydrase c is another protein abundant in intercalated cells, and this was also expressed in six of the ten oncocytomas investigated. Immunoreactivity specific for band 3 and carbonic anhydrase c was not detected in any of the 20 renal cell carcinomas examined. At favourable section plan…