in order to increase the water content and the oxygen permeability of hydrogels used in themanufacture of contact lenses, the polar monomer silicon hydrogel contact lenses (shcl), and 2-hydroxyethyl methacrylate (hema) were copolymerized with the hydrogels. due to the presence ofpolar monomers in the conventional contact lenses, the major component of the human tear,lysozyme is extensively adso...

Resin-based dental restorative materials contain allergenic methacrylate monomers, which may be released into saliva after restorative treatment. Monomers from resin-based composite materials have been demonstrated in saliva in vitro; however, studies analyzing saliva after restorative therapy are scarce. The aim of this study was to quantify methacrylate monomers in saliva after treatment with...

Bioactive films were produced by conjugation of a short peptide onto modified cellulose nanofibrils (CNF). Specifically, a hydrophilic copolymer, poly(2-aminoethyl methacrylate hydrochloride-co-2-hydroxyethylmethacrylate) (poly(AMA-co-HEMA)), was grafted via surface initiated polymerization from an initiator coupled to CNF. The poly(AMA-co-HEMA) was used as a spacer and support layer for immobi...

N,N-dihydroxyethyl methylacrylamide (DHEMAA), which is a methacrylate modified by diol, has been prepared by reaction of diethylanol amine with methyl methacrylate. UV curable urethane methacrylate oligomers have been synthesized by the reaction of a series of diol, triol, DHEMAA and HEMA with TDI or IPDI in two reaction orders. The first reaction style is the TDI or IPDI reacted with HEMA firs...

The drying kinetics were examined in four cross-linked polymers that form hydrogels: 2,3-Dihydroxypropyl methacrylate (DHPMA) and 2-hydroxyethyl methacrylate (HEMA) and two random copolymers, with one-to-one and three-to-one HEMA-to-DHPMA molar ratios. The hydrogels were saturated with buffered, isotonic saline solution and deionized water; weight loss kinetics were monitored at temperatures fr...

Polymerized resin-based materials are successfully utilized in medical applications. One draw- back is the release of monomers from the matrix due to an incomplete polymerization or degradation processes. Released monomers can diffuse in the systemic circulation and induceadverse effects to biological tissues. Although there are many hypotheses about the induction of cell death by resin monomer...

Previous studies have shown a wide range of pulpal reactions to dentin bonding systems and a poor correlation between in vitro and in vivo toxicity of dentin bonding agents. Because dentin bonding agents are composed of multiple components which may diffuse through dentin, we hypothesized that these components may cause cytotoxicity through interactive (synergistic) effects. We investigated the...

In Human Erythroid Massive Amplification (HEMA) cultures, AB mononuclear cells (MNC) generate 1-log more erythroid cells (EBs) than the corresponding CD34(pos) cells, suggesting that MNC may also contain CD34(neg) HPC. To clarify the phenotype of AB HPC which generate EBs in these cultures, flow cytometric profiling for CD34/CD36 expression, followed by isolation and functional characterization...

OBJECTIVES The purpose of this study was to analyze the behavior in water, related to mechanical properties, of experimental composites for dental restoration. METHODS The studied materials were composed of a visible-light-curing monomer mixture (Bis-GMA and TEGDMA or HEMA) and micrometric, nanometric or a mixture of both sizes hydroxyapatite particles as a reinforcing filler. Filler particle...

The aim of this study was to evaluate the effect of four different storage media on the elution of monomers from two composite materials. Samples (n = 10, diameter: 4.5 mm, thickness: 2 mm) of two different composite materials (Ceram X™ & Filtek™ Supreme XT) were stored after polymerization in four different media (NaCl, saliva, ethanol 75% & acetone) for 24 h, 7 days, and 28 days. From the sto...