Search results for "Acrylic Resins"
showing 10 items of 55 documents
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…
Current dental adhesives systems. A narrative review.
2012
Adhesive dentistry is based on the development of materials which establish an effective bond with the tooth tissues. In this context, adhesive systems have attracted considerable research interest in recent years. Successful adhesive bonding depends on the chemistry of the adhesive, on appropriate clinical handling of the material as well as on the knowledge of the morphological changes caused on dental tissue by different bonding procedures. This paper outlines the status of contemporary adhesive systems, with particular emphasis on chemical characteristics and mode of interaction of the adhesives with enamel and dentinal tissues. Dental adhesives are used for several clinical application…
A comparative assessment of acceptance of different types of functional appliances
1998
Patients' acceptance of an orthodontic appliance may influence compliance and thus contribute to a successful outcome of treatment. The aim of this study was to assess the influence of shape and design of different types of functional appliances on their acceptance by patients. For each of 10 adult volunteer subjects employed in the study eight different functional appliances were fabricated which had a varying extension of the resin base and amount of interocclusal opening. Effects of appliances on speech, initial acceptance, and acceptance after wearing were assessed by means of standardized tests. Amongst the appliances tested the bionator, functional corrector FR-I and elastic open acti…
Accuracy of check-bite registration and centric condylar position
2002
In a dentate subject a jaw relation can either be determined in maximum intercuspation and is as such given by the occlusal morphology, or the mandibular position can be allocated according to the centric position of the condyles. For comprehensive restorative treatment or analytic measures of the occlusion it is important to record the centric condylar position. Various registration methods have been described in the literature, but there is no consensus on which is the 'best'. The aim of the present study was therefore to assess the accuracy of various registration methods and evaluate a possible influence of the used materials. Four dentists were involved in the clinical part of the stud…
Long-term follow-up of a multifocal apodized diffractive intraocular lens after cataract surgery.
2007
Purpose To report the long-term performance of the AcrySof ReSTOR SA60D3 intraocular lens (IOL) after cataract surgery. Setting University Hospital Maastricht, Maastricht, The Netherlands. Methods This prospective clinical trial comprised 44 eyes (22 consecutive patients) having cataract surgery with implantation of the ReSTOR IOL. Monocular and binocular uncorrected distance visual acuity, best corrected distance visual acuity, uncorrected near visual acuity, best distance-corrected near visual acuity, spectacle dependence, undesired visual symptoms, patient satisfaction, and incidence of posterior capsule opacification were analyzed 6 months and 3 years postoperatively. Results The mean u…
In Vitro Percutaneous Penetration of Acyclovir from Solvent Systems and Carbopol 971-P Hydrogels: Influence of Propylene Glycol
2005
The mechanism underlying propylene glycol (PG) effects on acyclovir (ACV) penetration through human epidermis were studied. Solvent systems and Carbopol gels containing increasing percentage of PG (from 0% to 70%, w/w) were used. Viscosity studies of both vehicles were carried out to characterise the influence of rheological behaviour. In solvent systems skin permeation values of ACV increase as the concentration of PG increase yielding a maximum enhancement ratio (ER = 10) for 70% PG. The release rate of ACV from gels was determined. Higuchi's model was used to estimate the apparent diffusion coefficient of the drug. These values show a decrease as the content of PG in the vehicle increase…
Polyacrylonitrile block copolymers for the preparation of a thin carbon coating around TiO2 nanorods for advanced lithium-ion batteries.
2013
Herein, a new method for the realization of a thin and homogenous carbonaceous particle coating, made by carbonizing RAFT polymerization derived block copolymers anchored on anatase TiO2 nanorods, is presented. These block copolymers consist of a short anchor block (based on dopamine) and a long, easily graphitizable block of polyacrylonitrile. The grafting of such block copolymers to TiO2 nanorods creates a polymer shell, which can be visualized by atomic force microscopy (AFM). Thermal treatment at 700 °C converts the polyacrylonitrile block to partially graphitic structures (as determined by Raman spectroscopy), establishing a thin carbon coating (as determined by transmission electron m…
Mucoadhesive Polymeric Films to Enhance Barbaloin Penetration Into Buccal Mucosa: a Novel Approach to Chemoprevention.
2018
Nowadays, chemoprevention by administering natural supplements is considered an attractive strategy to reverse, suppress, or prevent the evolution of premalignant oral lesions. In particular, Barbaloin exhibits anti-proliferative, anti-inflammatory, and anti-cancer properties, and it results useful in multi-therapy with classic chemotherapeutics. Therefore, in this work, mucoadhesive buccal films, as locoregional drug delivery system able to provide a targeted and efficient therapeutic delivery of Barbaloin, are proposed. Thus, Aloin extract-loaded Eudragit (R) RL100 or Eudragit (R) RS100-based buccal films were designed in order to obtain an easily self-administrable formulation capable of…
Preparation and characterization of hexyl methacrylate monolithic columns for CEC
2008
The preparation of hexyl methacrylate (HMA) monolithic columns for CEC separations has been investigated with two initiation systems: (i) ammonium peroxodisulphate and TEMED to activate the polymerization reaction, and (ii) by thermal initiation with AIBN. For both initiators, the influence of composition of porogenic solvent on morphological and chromatographic properties of monoliths was investigated. Two porogenic solvent systems, aqueous and non-aqueous media, were also studied for monolithic beds polymerized with AIBN. Under optimal conditions, low minimum plate heights (9.6 mum for peroxodisulphate, 8.4 and 10.0 mum for AIBN in aqueous and non-aqueous porogenic solvents, respectively)…
Peroxodisulfate as a chemical initiator for methacrylate-ester monolithic columns for capillary electrochromatography
2008
Organic monolithic stationary phases for CEC were synthesized in situ in fused-silica capillaries. Polymerization mixtures were composed of butyl methacrylate, ethylene dimethacrylate, and [2-(methacryloyloxy)ethyl]trimethyl ammonium chloride in the presence of a porogenic solvent, using ammonium peroxodisulfate as chemical initiator, and N,N,N',N'-tetramethylethylenediamine to activate the reaction. The influence of the amount of initiator, temperature, and composition of porogenic solvent on the physical and chromatographic properties of monolithic stationary phases has been investigated. A minimum plate height of 14.5 microm was obtained at 18 wt% of 1,4-butanediol in the polymerization …