Bond strength of resin-based restorative materials to fast-setting calcium silicate cement using different resin adhesive systems.

This study assessed the bond strength of resin-based restorative materials to fast-setting calcium silicate cement (Aarhus Uinversity, Denmark) when treated with each of two one-bottle universal adhesive systems. The cement surface (N = 256) was treated with a self-priming adhesive and a self-etch phosphate monomer-containing adhesive with and without etching of the cement surface. Specimens then received either resin composite or compomer restorative materials (n = 32).

Validation of a human saliva model for the determination of leachable monomers and other chemicals from dental materials.

This study aimed to prove the validity of a mixture of chemicals, including salts, small organic molecules, mucin, and α-amylase, as saliva surrogate ("artificial saliva") for assessing leakage of methacrylate monomers and other constituents from dental materials. To achieve this, we developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA), diurethane dimethacrylate (UDMA), bisphenol A glycerolate dimethacrylate (BisGMA), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), bisphenol A (BPA), and five homologues of ethoxylated bisphenol A dimethacrylate (BisEMA EO2-6) in unstimulated and artificial saliva, and compared their concentrations in the two saliva media following either spiking with a mixture of the compounds or incubation of test specimens of printed biomaterials. Test specimens were immersed in unstimulated/artificial saliva, incubated at 37 °C for 24 h, and saliva aliquots were extracted with methanol and subsequently analyzed by LC-MS/MS.

Preparation of a fluorinated dental resin system and its anti-adhesive properties against S. mutans.

Objectives: The purpose of this study was to characterize physicochemical properties and investigate anti-bacterial adhesion effect of dental resins containing fluorinated monomers.

Method: Fluorinated dimethacrylate FDMA was mixed with commonly used reactive diluent triethylene- glycol dimethacrylate (TEGDMA) and fluorinated diluent 1 H,1 H-heptafluorobutyl methacrylate (FBMA) separately at a mass ratio of 60 wt./40 wt.

Investigation on the antimicrobial activity of chitosan-modified zinc oxide-eugenol cement.

Coronal leakage and reinfection after root canal therapy is an important reason for endodontic failure. Zinc oxide-eugenol (ZOE) -based materials are often used as a coronal seal to prevent secondary infection. The antibacterial effect of ZOE cement is mainly due to leaching of eugenol from the material, but the effect is reported to decrease over time.

Bond strength between dentine and a novel fast-setting calcium silicate cement with fluoride.

The aim of this study was to evaluate the dentine bond strength of a novel fast-setting calcium silicate cement (Protooth) versus a calcium hydroxide-based cement (Dycal), a calcium silicate cement (ProRoot MTA), and a glass ionomer cement (Ketac-Molar). Mid-root dentine slices of 1 mm thickness were obtained from human maxillary incisors. After enlarging the lumen of the canal to 1.

Effect of methacrylated chitosan incorporated in experimental composite and adhesive on mechanical properties and biofilm formation.

The lifespan of a resin-based restoration is limited, with the main reason for failure being secondary caries. Biofilm formation at the tooth-material interface is a necessary etiological agent for caries development. Dental materials with antimicrobial properties may reduce formation of biofilm and thus increase the longevity of restorations.

Preparation and characterization of Bis-GMA-free dental composites with dimethacrylate monomer derived from 9,9-Bis[4-(2-hydroxyethoxy)phenyl]fluorene.

Objective: Synthesize a new BPA-free monomer for use in methacrylate-based materials and evaluate critical properties of resin and composite materials based on the monomer.

Methods: Bis-EFMA was synthesized through reaction between 9,9-bis[4-(2-hydroxyethoxy)-phenyl]fluorene and 2-(methacryloyloxy)ethyl isocyanate. Experimental Bis-EFMA-based resin (Bis-EFMA/TEGDMA=50/50, wt.

Water sorption and solubility of polyamide denture base materials.

Some patients experience adverse reactions to poly(methyl methacrylate)-based (PMMA) dentures. Polyamide (PA) as an alternative to PMMA has, however, not been well documented with regard to water sorption and water solubility. The aim of this study was to measure water sorption and water solubility of two PA materials compared with PMMA, and to evaluate the major components released from the PA materials and the effect on hardness of the materials.

Antibacterial and Antibiofilm Effect of Low Viscosity Chitosan against Staphylococcus epidermidis.

Aim. The aim of this study was to investigate the antibacterial and antibiofilm properties of low viscosity chitosan on S. epidermidis growth and biofilm formation.

Interactions of liposomes with dental restorative materials.

The in vitro adsorption and retention of liposomes onto four common types of dental restorative materials (conventional and silorane-based resin composites as well as conventional and resin-modified glass ionomer cements (GIC)) have been investigated due to their potential use in the oral cavity. Uncoated liposomes (positively and negatively charged) and pectin (low- and high-methoxylated) coated liposomes were prepared and characterized in terms of particle size and zeta potential. The adsorption of liposomes was performed by immersion, quantified by fluorescence detection, and visualized by fluorescence imaging and atomic force microscopy.

The influence of bis-EMA vs bis GMA on the degree of conversion and water susceptibility of experimental composite materials.

Objective: The aim of this work was to assess the influence of the bis-EMA content on the degree of conversion (DC) and its effect on the water sorption and solubility.

Materials And Methods: In a polytetrafluorethylene (PTFE) mould, 30 samples (Ø = 5 mm, height = 2 mm) of four experimental dental composite resins were cured for 10 s, 20 s and 40 s. The DC was analysed by Fourier Transform (FT)-Raman spectroscopy.

Detection of leachables and cytotoxicity after exposure to methacrylate- and epoxy-based root canal sealers in vitro.

Root canal sealing materials may have toxic potential in vitro depending on the cell line, cytotoxicity assay, material chemistry, and degree of polymer curing. The aims of the present study were to detect leaching components from epoxy- or methacrylate-based root canal sealers and to investigate the degree of cytotoxicity after exposure to extracts from these materials. Qualitative determination of substances released from the materials was performed by gas- and liquid chromatography/mass spectrometry.

Effect of short LED lamp exposure on wear resistance, residual monomer and degree of conversion for Filtek Z250 and Tetric EvoCeram composites.

Objectives: The latest LED dental curing devices claim sufficient curing of restorative materials with short curing times. This study evaluates mechanical and chemical properties as a function of curing time of two commercial composite filling materials cured with three different LED lamps.

Methods: The composites were Filtek Z250 (3M ESPE) and Tetric EvoCeram (Ivoclar Vivadent) and the LED curing devices were bluephase 16i (Ivoclar Vivadent), L.

Detection and quantification of monomers in unstimulated whole saliva after treatment with resin-based composite fillings in vivo.

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 a resin-based composite filling material.

Identification and quantification of leachable substances from polymer-based orthodontic base-plate materials.

The aim of this study was to analyse leachable monomers, additives, and degradation products from polymer-based orthodontic base-plate materials. One heat-cured resin (Orthocryl), one light-cured (Triad VLC), and three thermoplastic materials (Biocryl C, Essix A+, and Essix Embrace) were investigated. Elution was performed in water at 37°C for 10 days.

Elution of substances from a silorane-based dental composite.

Previous studies have shown that residual monomers, initiators, and additives are eluted from methacrylate-based dental composite materials. Recently, a composite material (Filtek Silorane), based on a new resin chemistry, was introduced. The purpose of this study was to investigate substances eluted from Filtek Silorane in water and ethanol.

Pattern of cell death after in vitro exposure to GDMA, TEGDMA, HEMA and two compomer extracts.

Objectives: In vitro exposure to chemical compounds in dental materials may cause cell death by apoptosis, necrosis or a combination of both. The aim of this paper was to evaluate aqueous extracts of freshly cured compomers Freedom (SDI) and F2000 (3M ESPE), and constituents identified in the extracts, GDMA (glycerol dimethacrylate), TEGDMA (triethylene glycol dimethacrylate) and HEMA (2-hydroxyethyl methacrylate) for their ability to induce necrosis and apoptosis in primary rat alveolar macrophages and the J744A1 macrophage cell line.

Methods: The cells were exposed to either extracts of freshly cured samples of the products or to one of the constituents identified in the extracts.